Forming compound curves in heavy aluminum plate

[BillyDoc]

Does anyone have experience forming compound curves in 1/2” aluminum (5083) plate? I'm assuming I will have to build some machine to do this with but can't decide whether to pursue a “wheeling” approach or some form of “hammering.” I understand that the big shipyards use Eckold machines, and these certainly seem nice . . . but the price is a little (ahem!) beyond my budget!

Speaking of the Eckold machines, has anyone used one? And what is the operating principle? They look like they would be a “hammer” with a limited and precise stroke. Is this correct?

Any thoughts greatly appreciated!

BillyDoc

[Dagvald]

You need to investigate "english wheel". We hand formed compound curve sections on 53' round bilge aluminum hull. I
have photos. You could build one yourself. For forming aluminum I don't think you'd need hardened steel rollers. Industrial "caster type" wheels would do. It's surprising how little pressure is required on the wheels.

[BillyDoc]

Thanks for the info Dagvald. You're right, I could easily build an english wheel and even have a preliminary design for one cobbled up. And "wheeling" looks like it would be easier to actually do than the other approaches as well.

Do you remember how thick the plate was on that hull?

[Dagvald]

1/4" & 3/8". I think that the 3/8" may have been only in the twin keels which had a hydrofoil shape. I realize that you're concerned that 1/2" 5083 may be too "stiff" to hand form on the wheel. My opinion is that it can be done. My work partner on this job was a not particularly robust 76 year-old man. We made masonite templates of the hull curvature at at closely spaced stations on the hull and checked our progress with them as we worked the plate back and forth on the wheel.

You may want to look into the issue of work hardening of 5083 and the technique of annealing. We never found it necessary to anneal though.

On the assumption that you're talking about hull plating, the design of the hull framing may have some bearing on your approach. If the framing is both transverse and longitudinal you may have a structure stiff and fair enough so that you can "mold" the flat plate to the hull. In this case you'd use the fitter's repertoire of dogs and wedges, clamps, come-alongs and temporary fixtures to coax the plate onto the framing. An oxy-acetylene torch with a "rosebud" heating tip is hand for judicious warming to make the aluminum conform to the frame. Generally you'd start tack welding in the center and carefully work you way out as you simultaneously apply heat and tighten your clamps or whatever. By carefully I mean don't overheat an area - remember the torch can easily bring aluminum up to
its melting point!

You may be concerned about fitting this section of plating to plating already in place. I wouldn't try to pre-cut the whole piece and expect it to fit. If for instance if it was along the garboard I'd just transfer that line onto masonite and then onto the piece. I'd leave a couple of inches extra on the other sides and let them overlap. Once the garboard is fitted and you've tacked it appropriately then you can trim the overlap with your saw - set to cut just deep enough to make the trim cut.

What are you planning on building?

[BillyDoc]

Dagvald that is exactly the kind of information I was looking for. And your first guess was right, I'm planning on plating with half-inch over transverse and longitudinal framing. A twin-masted schooner, of sorts, of about 44 feet. I can foresee the possibility of sailing where there is the occasional iceberg, and I just plain like "sturdy" far more than I care about "fast." I also think that I can come up with a much more seaworthy craft with the extra weight to play with.

It should also be easier to control distortion using the heavier plate, and as I intend to TIG weld all seams this is definitely an issue.

As for the wheel itself, I was toying with the idea of substituting a reciprocating flat bed (picture something like a vertical milling machine table) for the larger (usually upper) wheel that can be powered back and forth with (perhaps) a foot control, and "anvil" wheels that come down from the top and apply pressure. This way the curvature will cup upward at the edges rather than the usual downward direction with a conventional wheel. That upward curvature will make it easy to suspend lines to the edges of the plate with counterweights to partially support it. It doesn't take much half-inch plate to get a little awkward to handle!

My understanding is that 5083 is quite workable with wheeling, and presumably the extra thickness won't make too much difference if I just scale the wheeling machine up proportionately. With a suspension system and a powered wheel I think I can make it all work without breaking too many muscle fibers. I'm getting old and I'm not as strong as I used to be . . . but I AM getting near to having the time to build and go off a sailing! And I've been dreaming of making my own yacht for years now.

Thank you very much for the information!

BillyDoc

[Dagvald]

Hi BillyDoc,

Thanks for telling about the 44 footer. My first thought on the idea of 1/2 bottom plating on a vessel that size is the cost. If your concern is icebergs, why not think about the design of the bow, keel, skeg and rudder to give you the best chance of avoiding damage in the event of a collision. Yes, 1/2" plate is extra weight, twice as much as 1/4" and twice as expensive. Put the weight down in the keel as ballast. Spend money you save on good radar, extra heavy rigging, storm sails, SSB, sextant, charts and a reliable cabin heater!!!

You could put some extra framing in bow area, watertight bulkhead foreward, nicely slope to front of keel and bow. These types of things. Alum is super tough stuff! It'll stretch quite a bit before it lets go, compared to steel. I believe this is called "modulus of elasticity".

A note on welding 1/2" plate: I think you're going to spend three to four times more man hours welding if you try to TIG all those hull seams. Have you done much TIG welding? Man, you are talking a lot of work, electric bill, argon. I spoolgun MIG is the way to go. Use the TIG for tanks, fussy stuff on light gauge that you want to look good to impress the landlubbers. If you are working by yourself how are you going to tack and hold a piece or a tool and push in the TIG filler rod at the same time? There's a way to do it (weld a little pea of filler by the place you want the tack) but that's time consuming and a pain in butt. I could go on but I think you get my point. I love TIG but not when I'm climbing around inside a boat. I recommend 1/4" plate on the hull, 3/8" plate in the bow sections for peace of mind and 3/16" deck and house.

I'd worry more about getting trapped in a floating ice pack than smacking into an ice berg. Where are you planning on building? -Dag

Attached photo SV Setteroses (Seven Roses) I sailed many miles on her with her lovely Captain Laura Zolo although not up north when photo was taken as I hadn't met her yet. She from Scotland, Orkneys, Shetlands, Iceland, Greenland, the Northern Route. Seven Roses is steel hull, an abandoned shipwreck when Laura found her on Cape Verde beach, purchased for one French franc from insurance company.

[BillyDoc]

Hi Dag,

One franc?!!! That has to be the bargain of the century!

The bit about the ice was because I keep wondering what it would be like to give the Northwest Passage a try. And I live in Florida and hate cold weather with a passion! I think I'm losing brain cells at a rapid rate as I age.

I'll be building a building to build the boat in on a tree farm my wife and I own near Pensacola. 160 acres of pine forest with springs and flowing clear water over snow-white sand. We spend most weekends there, and I can really see "camping" out there while building (we have an old Airstream trailer out there for our weekends). The building plans are for a 40' by 60' building with 18' clearance . . . and with heavy steel beams holding the roof up that can be used to hoist and manipulate the hull. I've been TIG welding for seven or eight years now (Miller Syncrowave 350) and I love the quality of the welds you can do with that machine. You are definitely right about the time involved though. My plan is to minimize the "crawling around" part as much as possible by doing most of the interior welding first while standing on the floor reaching between the frames, doing the plating and deck last.

I also really hate to weld upside down, so I plan on being able to rotate the entire hull as needed to avoid this. Lots of strong points overhead and several chain hoists attached to them should facilitate this. I'm also going to go ahead and pay a CNC shop to waterjet-cut just about everything so that I'm basically putting together a “kit” just like I used to do as a kid with plastic models.

I'm very fortunate in that I already have a wide assortment of tools to apply to this project, including a CNC computer-linked milling machine. The only tool I lack is the means to bend those compound curves, and from what you have said I don't think that will be too much of a problem.

Being somewhat demented, I'm actually looking forward to days and months of building! It will be in a very nice environment, peaceful and quiet with nobody to disturb me. Almost like sailing, but with green stuff all around. And watching something come together under my own hands has always been a thrill for me.

As for the cost of the aluminum . . . well yes, it will probably double the way I'm planing to build, but the cost of the material is actually a fairly small part of the overall cost of a good yacht. And besides, I have to be able to show my wife the hull and say “Look at this, Honey, you'll be safe in here! Even if we do get another one of those nasty hurricanes while we're way out at sea.” The point about the hurricanes being one that has been raised . . . often. We had an interesting year in that regard two summers ago. We both also get pretty seasick sometimes, and a heavy boat can be much more comfortable than a light one.

BillyDoc

[Lyle Creffield]

Unfortunately the North West Passage will again be navigatable as it was in 1420 CE due to gloabal warming!

I have researched the time to weld 10 mm 5083 (12.5 = 1/2 inch) plate (Mig), 3 passes, sonic test - work on arround one hour per metre

Eckold machines? who or where?

i once looked at designing a machine which was feed flat plate and pushed out a compound curved plate

[BillyDoc]

Hi Lyle,

I'm actually looking forward to the Northwest Passage . . . for some stupid reason. And I am well aware of the disaster it portends. Oh, well, our species just insists on consistently doing the stupidest things possible, like in this case destroying our collective home for individually selfish reasons.

But you asked about the Eckold machine. It really looks like a fine piece of equipment, but I found a used one for a "mere" $45,000! And I don't have that kind of "spare change" at the moment. You can see what they can do at their web site here: http://www.eckold.ch/umformen/e_um_Homepage.html (I'm referring to the big Kraftformer).

I can't tell just from the pictures, but I'm guessing that the working principle is a very well controlled reciprocating "hammer" with various specialized dies. By this I mean that the force applied with each stroke is very high, but the stroke distance is precisely controlled, and the dies may have built in "tricks" like parts that expand laterally when force is applied (for shrinking or expanding a compound curve). I would really like to learn more about this machine, as I could design something similar fairly easily if it is as I imagine.

Your welding time estimate is very useful as well! I will probably need to double that for TIG . . . which means I'm going to be REALLY OLD before I do any sailing.

What approach were you thinking of for producing compound curves?

BillyDoc

[Lyle Creffield]

Hi Billydoc

Today my aim is hard chine and more sailing time

cheers

[john frater]

Have a look at this site:www.radford-yacht.com/wheel he has plans for a wheeling machine available

[BillyDoc]

Thanks for the link, John. You need to edit it to add .html at the end though.

The pictures of the large "commercial" machine are very interesting. I am becoming more convinced than ever that this is the way to go . . . and building a wheeling machine doesn't look that hard to do at all!

Compared to building a yacht building the machine to use seems downright simple, actually.

BillyDoc

[john frater]

Hi Billy Doc

There is actually a wealth of information on similar machines if you search 'English Wheel' or 'Planishing Wheel' but I think that the one designed by Graham Radford is best suited to boat building. I would be really interested to know how you get on with the machine. I have heard of using very hard rubber compound for one of the wheels to avoid leaving lines in the plate.

John Frater

[jmac]

Graham emailed me the plans for his english wheel. All I did was ask him for some information on it and he sent me a dwg. of the plans.

[BillyDoc]

Hi John,

I've heard about the hard rubber myself, and some people apparently buy large industrial grade castors with urethane treads for this purpose as well. It apparently works quite well!

Hi Jmac,

I understand your surprise. When we watch our "leaders" run through their evil plots, or listen to the constant deluge of scare-garbage from the mass media, it's easy to forget that there are many, many very nice and helpful people out there, and I think you just found one. Good to know and start the New Year with, isn't it.

BillyDoc

[Lyle Creffield]

Hi Billy doc

i seconded your comments that there are many helpful persons who use boatdesign net

research shows that a little help to understand something goes a long way in the learning process

thank you to all those highly tolerent persons for their most imformative responses

lyle

[lazeyjack]

1/4" & 3/8". I think that the 3/8" may have been only in the twin keels which had a hydrofoil shape. I realize that you're concerned that 1/2" 5083 may be too "stiff" to hand form on the wheel. My opinion is that it can be done. My work partner on this job was a not particularly robust 76 year-old man. We made masonite templates of the hull curvature at at closely spaced stations on the hull and checked our progress with them as we worked the plate back and forth on the wheel.

You may want to look into the issue of work hardening of 5083 and the technique of annealing. We never found it necessary to anneal though.

On the assumption that you're talking about hull plating, the design of the hull framing may have some bearing on your approach. If the framing is both transverse and longitudinal you may have a structure stiff and fair enough so that you can "mold" the flat plate to the hull. In this case you'd use the fitter's repertoire of dogs and wedges, clamps, come-alongs and temporary fixtures to coax the plate onto the framing. An oxy-acetylene torch with a "rosebud" heating tip is hand for judicious warming to make the aluminum conform to the frame. Generally you'd start tack welding in the center and carefully work you way out as you simultaneously apply heat and tighten your clamps or whatever. By carefully I mean don't overheat an area - remember the torch can easily bring aluminum up to
its melting point!

You may be concerned about fitting this section of plating to plating already in place. I wouldn't try to pre-cut the whole piece and expect it to fit. If for instance if it was along the garboard I'd just transfer that line onto masonite and then onto the piece. I'd leave a couple of inches extra on the other sides and let them overlap. Once the garboard is fitted and you've tacked it appropriately then you can trim the overlap with your saw - set to cut just deep enough to make the trim cut.

What are you planning on building?

you cant wheel to the edge of a plate, allow 60--75 mm in topsides first run you can use most of the plate as there is lil shape, but anywhere else alow that much see my gallery
Eckold squeeze recipricating presses have ltd .use and are two man operation, you can form pretty much all using small v wheels, once gain see the nose in my gallery Up to 8mm with not excessive shape you can use urethane wheels leave sno marks but then the marks are all inside except on a clipper bow when the forming is other way

[lazeyjack]

and anyone who heats a plate is an amatuer, you NEVER heat alloy, ever. it is possibel to form a plate so close to the desgned shape that only light pressure is necessary to bring it home

[BillyDoc]

Lazyjack,

Thanks for the info. I've pretty much settled on a bloody great wheel with a hydraulic drive so I can control it easily, and not use my own muscles for power. I know it seems crazy, but I have become convinced that half-inch plate is the way to go.

Here are some reasons:

Heavy aluminum plate is much less subject to heat distortion during assembly.

Given that the density of aluminum is roughly 34% of steel, the equivalent steel plate to half-inch aluminum (by weight) would be 0.172 inches thick, which is not unreasonable for the hull of a steel boat of similar length. The aluminum is much stronger though.

Butt welds have much more area, so are stronger (assuming a complete fill, which is easy enough if you first saw out the area right through to just short of the other side)

I will be using frames every 18 inches, longitudinals every 12 inches, so individual plates will not be too large to handle.

Expense aside, my very limited experience is that heavy plate is actually much easier to handle for a project like this than the light stuff. And besides, I want a real brute of a boat. The preliminary calculations for my half-inch thick hull give me a hull weight of 5,404 lbs, which doesn't seem too unreasonable for a 44 foot hull. I don't care about speed, I want seaworthiness above all other qualities.

The downside of a heavy hull is certainly welding time and supplies and initial material cost, which in this case will add roughly $7,500 compared to quarter-inch plate. But I don't see any other downside at all! That is, assuming proper equipment to handle that plate starting out, which I intend to have.

BillyDoc

[lazeyjack]

well wait and see, you are a stubborn bugger, If I was building a rocket I would listen to you,
no one asked you to build in 6, 8 is ok, have you ANY idea how hard it will be to stretch that 13 plate ? you have to stretch before you even start to form, the stretch in the centre of the plate, makes it go AROUND LENGTHWISE, the forming makes it go around bodywise Do you still have the draft of my book?
It should give the wheel speed in ft per minute Best is a planetary gear, driven by a fractional hp elec motor with a chain driving the wheel, pressure is applied through a screw Still what do i know I only personally built 32 alloy boats, If you think I,m getting cross you are right Stubborn bugger!!:))

[BillyDoc]

I hear you Lazyjack, and your words have made me very cautious about whether or not it is possible to form plate this thick! So, I'm going to build the wheel and try it before proceeding with the boat plans. That way I'll know for sure. I certainly prefer to go with the heavy stuff, but if it can't be done . . . then I guess it can't be done!

And If I put together an oversized wheel and find I still can't work half-inch plate . . . I bet it will work the thinner stuff just fine!

Thanks for the info! I really appreciate your experience and input.

BillyDoc

[lazeyjack]

I hear you Lazyjack, and your words have made me very cautious about whether or not it is possible to form plate this thick! So, I'm going to build the wheel and try it before proceeding with the boat plans. That way I'll know for sure. I certainly prefer to go with the heavy stuff, but if it can't be done . . . then I guess it can't be done!

And If I put together an oversized wheel and find I still can't work half-inch plate . . . I bet it will work the thinner stuff just fine!

Thanks for the info! I really appreciate your experience and input.

BillyDoc
ok, normally on the top run would start anything from 4 foot wide pl at bow and finish maybe .9m or 36 in at transom
second run narrower and and tapering maybe to 20 inches at transom
because you a re doubled ended, your plates are going to get very narrow at stern, your trim waste will be 40% = of the pl width here, as you will need that extra width that you cant wheell
You will make a pattern at every frame. for every plate you may have 10 by your side by the wheel as you work, the plate must fit that pattern exactly right out to the end of the pattern which will look like a slice of new moon
its not so crucial in flatter areas BUT any boat with shape, needs wheeling no matter how small the curve, because if you force the plate, when you weld it, it collapses in that area, Of coarse there is an alternative, BOG, thick red microballons,
you see that default hull in delft? well look at the grey lines in the body and that is something like your plate scheme would be Except the line would drop at the bow , in other words the top run at bow is the widest plate nearer the time I will draw your plate plan for you

[lazeyjack]

oh I did not say it was impossible , I said becuz your yacht is short and with much compound, it would be very very difficult If you look at that keel in my gallery(which I did not build) you will see anything is possible with skill, they built a very complex press for this, and the plate was THICK

[BillyDoc]

Lazeyjack, The nose of the Millennium 55 in your gallery . . . how thick is that? Looks like it was a pure bitch to do!

[lazeyjack]

no it was fun, took 5 hrs, we layed the machine down, I built littel former wheel, and a girlfriend worked the fwd reverse switch, I had a pattern for every waterline
was 6mm, and boy once its formed it as strong as a pipe, the the painters bogged all over it!!:((

[lazeyjack]

very slender up there and I welded permanent backing bars to the inside of the nose edge cos there was no room from inside to get to it. At the forefoot, 8mm, is so strong 5083 that once formed you can not move it with a 15 lb hammer, this is why I cant get to grips with the 13 pl idea

[lazeyjack]

this is the best (fairest yacht) I have ever seen, built in Holland , unpainted there is some sort of preservative sprayed on the plate, the owner tell me she is built over frames only In that case it is quite exceptional, all weld penetrations have been removed and , well it just impresses so much.
the house is timber as is the deck, joined at the deck edge , timber is bolted to a shelf which runs around the sheer,
i have built same principle but used alloy deck and joined the house to it , by screwing to the flange the boat is in Mooloolaba at mo, on world cruise

[SkipperSki]

You might want to check out, Grizzly Industrial, Inc. their catalog is free.
www.grizzly.com

Every Metal or Woodworking Shop, should have this catalog on the book shelf.
If you go to the web site, enter in the following model #'s

Casters; H0655
English Wheel; G0496
Planishing Hammer; G0497
(while both these are for light gage (16 ga.) mild steel) and would be suited for lighter metal boat builder, but give you an idea of each form.

I hope this is useful info !

[BillyDoc]

SkipperSki,

Thanks for the link! I've got it bookmarked.

BillyDoc

[Lyle Creffield]

Hi BillyDoc

12mm is thicker than most
Firstly, i am not a naval architect
But I am a strong believer in thick skinned ally for 12m plus sailing vessels
One of the more capable Australia designers Graham Radford who trained under David Adams said to me when discussing his Radford 14 #47 that the first boat that was built had a 6mm hull - he described this as "very strong" considering the overall design
For practical purposes i consider 8, 10, 12mm as thick in comparison to the excepted norm
Advantages: Most can weld to and join such plate without distortion, corrosion will always be an issue but with thick plate it can be reliable repaired, and last a very long time

Here i would like to clarify my design parameters if you will so allow

Blue water-ocean going vessel, that will remain water tight providing there is keel to ground clearance, a hull that has the highest resale value by way of an almost indefinite lifetime (we only think we build for ourselves), and ease of construction - too many hulls never get completed primarily because of the excessive hours caused by construction design, fit out is a big job in itself

I am guessing we are on similar paths save that i intend to mass produce after the my prototype is completed

Can 12mm plate be bent (compound curvature i assume)to your design without such deformation as to cause lost of strength and possible corrosion problems (from external radius stretch) as to defeat the original aim of strength and resistance to corrosion?

Life is about balance and so to is vessel design (most call it compromise)

I believe that parking a 10mm hull on a reef would have similar consequences to doing so with a 12mm both would likely survive with some dents and scratches why do 12mm when 10mm may do?
A similar argument could be raised for 8mm but not 6mm in my view

I have long had an idea (and many sketches) of a large multi wheeled machine computer driven that can feed 6m by 2.4m plates back and forth to arrive a a desired compound curvature and once trimmed become part of a section of preformed hull - but have not located the entrepreneurial capital required

So without such a machine 12mm plate and tight compound curvature will be very time consuming or ... consider single chine, frameless initial construction, then fit frames, upright construction, estimate hull construction less keel, rudder and skeg of less than 400hrs, arround 1000hrs is more often the norm - food for thought?

I have built a 1.5m model of my CREF15, 15m LOA, 15t, 4.2m beam, hope to build a 3m 1/2 hull over Christmas before having the design checked by a naval architect and NC file produced


good luck and best wishes

[mydauphin]

This is going to sound silly but it works.
I needed to bend a 1/2 inch plate for Door. We made mold out of Concrete and drove my diesel pickup truck over plate a few times to bend it. Used propane torch to make it stay bent.

[BillyDoc]

Lyle,

It seems we have a similar design philosophy. I'm now in the process of working on the weight and balance aspects of my design however, and as it turns out I backed off the hull thickness to 3/8" (9.5 mm) because of weight. Given Lazeyjack's comments, and yours, I am not too "broken up" about this, as I suspect he is right about the difficulty involved using half-inch plate, and you are right about the consequences of both . . . and the 3/8" plate should still give me a very rugged hull.

And in the meantime my wife has been giving me grief about the time involved in building a boat and has been searching the web for one to buy instead . . . with absolutely no luck at all! Very rarely is hull thickness even mentioned in the advertisements she shows me, and in one case a 3/16" hull was bragged about as "well above the accepted norm," making me really wonder about boats built to the "norm." On another aluminum boat she found you could see ridges from the frames like the ribs on a starving horse . . . which made me seriously wonder how thin that one was. Hull thickness was not mentioned, of course, but I bet it is nice and light for racing. Even so-called "expedition" boats all seem way too fragile to me. Of course, the folks who buy these boats have probably never actually been to sea in a storm, so they have no idea of the forces involved when things really kick up.

I too have dreamed of some machine to quickly produce compound curves in plate. Mydauphin suggests a concrete form and pressure in the post after yours, and this will certainly work for a limited number of items. Taking a similar approach, there is hydroforming as well. With hydroforming you could make your concrete mold and put it in a massive frame with a flat plate of the material you want to form cut to fit in a mating piece with a rubber layer just above it into which water is pumped at high pressure. Lots of industrial items are made with hydroforming and it works extremely well . . . but you need a separate mold for every part. This actually might not be so bad given how cheap concrete is, but in my own case with roughly 900 square feet of hull and imagining a hydroforming press of, say, 9 square feet . . . yikes! One hundred molds to make and mess with. Along these same lines I have also thought it would be possible to make a variable-shaped mold with a "bed" of hexagonal rods with spacers to get the desired curvature. Each rod could be domed with a slight curvature, and when the flat material was pressed into it you would end up with an array of "dimples" where the metal was pressed against the rods. Or, each rod could have a pivotable flat attachment. Such a bed of rods would also make a fine curvature gauge if provision was made to lock the rods in place. All of which just gets too complicated for a one-off effort. Another possible way to go is explosive forming, which works well, but may upset the neighbors.

I'm very interested in your approach to this problem, Lyle, so keep in touch! It's nice to know that I'm not the only crazy dude who wants a sturdy hull. Maybe this feeling comes from early experiences on a WWII aircraft carrier with 18" of steel armor. The bow of that boat was split in a storm once when I was aboard, but then it was only an inch and a half thick up there. Armor steel, of course. Ripped in two by a nice, soft, watery wave. Another mere wave took off all the catwalking forward for about 200 feet, and removed the ship's bell in the same move. It sure taught me some respect!

BillyDoc

[mydauphin]

Hull thickness... H'm ...I did not think about it when you said it. I have a professionally designed and built Aluminum 70' Motor yacht and only part of hull that 1/2" thick is transom and motor mounts. Both of these are straight. Hull is a combination of 5/16 and 3/8. There are a lot of weld braces and internal structure. Remember the hull skin is just that. Aluminum is very strong. I bought my boat after a hurricane threw it on its side against the rocks. The dents incur where no more than 3 inches deep. They where local and where repaired by welding a new piece over it.

I would spend my times and money - not on thickness but design, actual quality of metal and anti-corrosion treatments of hull.

[korvello]

BillyDoc; have u finished your project ,have pics and can i contact u thru e-mail, thank you k.

[BillyDoc]

Korvello,

By all means contact me about anything. My project is still in the design phase, however, I'm just starting to do a structural analysis of the rig which I hope to begin today. I still have several "details" to work out on the hull as well, and get weights for, but most of the major stuff is done . . . if I don't have to go back over this %@#^*@ "design spiral" AGAIN. Assuming that works out I'll go over the basic hydrostatics again and if that works out as well I at least "believe" that I have a viable design to begin making hardware for. My first job, however, will be building a building to build the boat in. I've ordered a quonset style steel building which I plan to basically use as a roof on some heavy concrete stem walls to build in, and I just heard yesterday that they will ship it on the 20th. That felt like real progress! This is definitely a long-term project.

No pictures, but I do have drawings up here if you're curious: http://poiesisresearch.com/lieserl.php. I haven't updated this page for a while now and the design has evolved, but I expect to do another update sometime this week.

BillyDoc

[korvello]

thank you BD; i'm in the process of designing my aluminum cat and do not intend to build till maybe next year ,got caught in other things ,my curiosity is because having read some of your posts we have a similar building approach of making it strong first and everything else is secondary...i was curious on your choice of aluminum and from what supplier and also about your welding ,are you going to TIG the whole thing and like you i intend to make my boat rotate on an axxis to be able to weld easier and on the flat.....maybe if it will be ok with you even visit your shop to learn a little or maybe even give you a hand ......k

[korvello]

BD; also looked at your renderings and they look good ;who made them and with what software? thank you k

[BillyDoc]

Hi Korvello,

Glad you like the renderings, they're from Rhino but using a screen-capture program to actually grab them. I used Delftship to do the hull, then moved it to Rhino with RhinoMarine to do the rest. Rhino is turning into a very nice program, by the way (version 4). Everything actually works almost all of the time, unlike a good number of other programs I have tried. Delftship is excellent as well, and the Freeship version is also quite good, or downright superb if you factor in the cost!

The aluminum alloy I will be using is 5083 in the marine grades (H116 or H321) and I will be TIG welding the whole thing. There is a lot of controversy around TIGing a large structure such as a yacht . . . it's slower than MIG, it uses more power, and both of these factors result in more opportunity for heat distortion. On the other hand, TIG makes a better, stronger and neater, weld BECAUSE it uses more heat to melt the filler into the surround and can do so without uselessly piling up molten wire all over the place, and if you turn up the power it is almost as fast. Both have their advantages, obviously. I anticipate spending a LOT of time waiting for things to cool down so I can continue, though. You know: "Honey, I am working! I'm sitting here waiting for it to cool down so I can weld some more."

I still haven't sorted out a supplier for the metal yet, and this is complicated because I want to go the cutting file approach for a lot of the parts. Layout is a real art form in and of itself . . . and I would just as soon avoid it as much as I can.

BillyDoc

[korvello]

Hi BillyDoc :............................................................................................................................................................. thank you for taking the time to write back. interesting you would TIG the all thing i love it ,that and using twice the tickness of plate it sure goes against most so called experts opinion; i'm with you, after examining guys like Dashew and what they call good enough or more than it's called for i intend to build with 3/8 minimun below water line , i have no intention of caring a kill switch with me just in case i hit something , so much for believing in what you have built,ridiculous. some will argue that the new mig welders can match a tig weld ,what do you think about it ? have you consider 5086 , the us navy apears to be sold on it and it's somewhat more maleable ,but then again 5083 have slightly better numbers and is the favorite of most guys down under and will probably be my choice because i dont intend to have no compound curves to speak off , i wish i could find 3/8 on coil that would make a nice hull with no vertical welds .what prices do you have for 5083 ? thank you k

[BillyDoc]

Korvello,

I haven't bought any metal yet, so I can't comment on price. From what I've read, I expect something like $3 a pound . . . probably more now with our dollar dropping like a lead sinker in Missouri River water (too thick to drink, too thin to plow).

In my lonely opinion MIG will never compete with TIG for quality of weld, and TIG will never compete with MIG for speed and less problem with heat distortion. Everything's a compromise, you go with what's most important to you.

5086 is also good stuff, but I have a lot of respect for those folks in Oz who use 5083 and figure that they know something I don't, so 5083 it is for me!

BillyDoc

[mydauphin]

Korvello,

I haven't bought any metal yet, so I can't comment on price. From what I've read, I expect something like $3 a pound . . . probably more now with our dollar dropping like a lead sinker in Missouri River water (too thick to drink, too thin to plow).

In my lonely opinion MIG will never compete with TIG for quality of weld, and TIG will never compete with MIG for speed and less problem with heat distortion. Everything's a compromise, you go with what's most important to you.

5086 is also good stuff, but I have a lot of respect for those folks in Oz who use 5083 and figure that they know something I don't, so 5083 it is for me!

BillyDoc

Having actually mostly built a hull - a few ideas...

I used small MIG to tack weld pieces quickly. Then a big mig to weld piece together, Then used Tig to finish welds and make pretty.
I have found it is easier to sandblast or grind piece then prime with zinc chromate, then grind off where I am going to weld later. Unfornately sometimes you dont do everything in one day and when you come back to it. Then you have to start by cleaning everything. I had to build y boat in the open and it was a pain.

Buy the best/most powerful welding equipment you can, it will make your life easier in the long run.

Find a good AL like Betsy at http://www.adimetal.com/
AL has double in price since I started 3 years ago, so has Stainless, Copper, etc...

I used 5086 for hull but used 5083 for firewalls and other part. Also used 6063 Extrusions for roof structure . In other AL is expensive, sometimes you can use other than marine AL for above waterline if you keep it painted.

Also first thing you do is paint bilge, it will save you alot of problems later.

To work on AL boat you need a nice clean area hopefully with a roof. I dont have one and it has cost many months of work.

[BillyDoc]

Mydauphin,

Good advice! And worth every penny, and more. I bought a quonset style steel building to build in and it is scheduled to be shipped on the 20th of this month. I figure it will take me about three or four months to get foundations and everything ready and the building up on them and the ends filled in, and then I can get my shop moved in and get started in near perfect conditions. No worries about rain, or wind blowing my gas all over the place . . . and I can leave my tools scattered all over just like I like them.

As for a good welder, I had a pile of cash about 10 years ago and bought a Miller Synchrowave 350 LX to upgrade some cheapo equipment I had been using . . . and I could hardly believe the difference! Like the difference between night and day . . . I love this beast of a machine! Even a crappy welder like me can make an excellent weld with this baby.

BillyDoc

[korvello]

thank you guys priceless advise and input .....BillyDoc 3 to 4 months to build the shop ,sounds like a long time, are you doing it yourself?..... been a contractor buildings is more my expertise and a building like yours is a 2/3 week job up here, wish i could say the same about boat building but that's why i'm asking so manny questions ,always cheaper and faster than trial and error.

[BillyDoc]

Hi korvello,

Doing it myself in the middle of a 160 acre parcel of Florida forest with, so far, no electricity and lots of trees in the way. Plus working on stuff to try and make that basic essential, money. And I'll be 64 years old next month, which means I don't move like I used to!

I expect a lot of "Motrin Mornings" in my near future . . . but you gotta do what you gotta do. Making things even more interesting, I got in a little, well, disagreement, with the people who sold me the building. They had promised a 150 mph wind rating (it gets "breezy" here sometimes), and part of the deal was engineering drawings for the building on 5 foot stem walls. When it came time to deliver the drawings the first set had no stem walls, and the second set had no engineering for stem walls and was plainly marked that they would be designed by someone else, at which point I offered to cancel the order. That got me a third set, and this time it was "complete" but not exactly "elegant" as it requires 102 yards of concrete and a thick matrix of bent-up rebar. When they sent the last drawings they had fulfilled the contract, and I'm stuck with it now. Oh, well, I like rugged. But this is going to be a pure bitch to actually do. I ache just thinking about it.

BillyDoc

[mydauphin]

Hi korvello,

Doing it myself in the middle of a 160 acre parcel of Florida forest with, so far, no electricity and lots of trees in the way. Plus working on stuff to try and make that basic essential, money. And I'll be 64 years old next month, which means I don't move like I used to!

I expect a lot of "Motrin Mornings" in my near future . . . but you gotta do what you gotta do. Making things even more interesting, I got in a little, well, disagreement, with the people who sold me the building. They had promised a 150 mph wind rating (it gets "breezy" here sometimes), and part of the deal was engineering drawings for the building on 5 foot stem walls. When it came time to deliver the drawings the first set had no stem walls, and the second set had no engineering for stem walls and was plainly marked that they would be designed by someone else, at which point I offered to cancel the order. That got me a third set, and this time it was "complete" but not exactly "elegant" as it requires 102 yards of concrete and a thick matrix of bent-up rebar. When they sent the last drawings they had fulfilled the contract, and I'm stuck with it now. Oh, well, I like rugged. But this is going to be a pure bitch to actually do. I ache just thinking about it.

BillyDoc

How big a boat are you building? How big a building? I am also contractor in Florida. 102 yds of Concrete. One could build a fairly large building with that alone.

[korvello]

BillyDoc; too bad i live so far [central california] ,i would gladly give you an hand ,are you close to water ?...maybe we could help each other i don't have a place to build yet, but even if you just need an hand let me know even if i'm in the midlle of building a big custom home [8500 sq ft covered area] i could find a few days to stop by and trade some of my experience in building for your welding and working with aluminum experience.

[BillyDoc]

102 yds of Concrete. One could build a fairly large building with that alone.

Definitely! That's why I say their design is not exactly "elegant." All of that concrete is to make a foundation and 4" thick floor for a building 50' wide by roughly 60' long. The 5' stem walls along the length are 14" thick, and buried in the ground 3', on a 4' wide base that is 12" thick. There is a #5 rebar vertical stirrup every 12" and a horizontal #4 rebar every 18". The end foundations are smaller, but the same principle applies - - - "Punish the dude that insisted that we do this, when it was obvious we were just kidding about it and don't want to bother doing these drawings." And I had to tell them that the ground loading wasn't the problem in a wind, the curved roof would lift, not get heaver! Oh, well. Live and learn. It won't blow away when we get the next big blow. This is also going to be my "hurricane hole."

The boat will be roughly 46 feet on deck (50 overall) with a 7.6' draft and 33,000 pound displacement.

Korvello, thank you so much for your kind offer! I think I can handle it though, I've worked out a way to set up the forms for the concrete that isn't too difficult and will be pouring each wall separately, so I only need one set of molds to do both stem walls, and similarly for the end foundations. I'll be closing the ends with concrete blocks and BIG steel doors (18' tall by 16' wide). I have a very nice loader (Tackeuchi TL150) with a boom attachment I made up that will help alot with the digging and leveling and lifting the "rings" for the building. I'll get it done eventually, but that's why I think it is going to take several months.

BillyDoc

[korvello]

you're welcome BD; i don't know who design your building but it must be from the same school that designs bridges in california no common sense or understanding of the forces involved........over here we usually dig 6 to 8 ft deep by 2 ft diameter holes where the posts/beams go with quite a lot of rebar and tying it to the floor and at leats a 1ft by 2 ft deep perimeter footing ,4" slabs is for side walks not a building specially if you are going to have 16 tons kind of localized in a certain area ,it should be 5 1/2" minimun with 1/2 rebar 18 o.c. each way, your stem wall looked ridiculous all you need is extra lateral bracing that sould extend from and be attached to perimeter footing to the top plate and or corner post and should be donne in all corners and be rigid enoug to be active both ways ........just my 2 cents ,good luck.

[BillyDoc]

You're absolutely right Korvello, and I tried to convince them of this and even sent them a drawing, but no deal. They really didn't want to do the drawings at all after they had my deposit, but I bitched and refused delivery until they did what they had promised, and I had in writing, and now that they have I'm stuck with them. I have to have the stamped engineering drawings to get a building permit.

I could just pay a decent engineer to re-do it, but that would eat up even more time (I've been fighting this battle for four months now) and would probably not save me that much over the cost of the extra concrete . . . so I've just decided to pay for the concrete and proceed. And as for the concentrated loads, I'm putting 4' x 4' x 16" pads at four places where a big gantry will be supported to hold the boat. When building I plan to be able to rotate the whole thing with four chain hoists to make the welding convenient and down-handed, then when it's all done I'll put the lead in the keel and hoist the whole thing up to back a low-boy trailer in under it.

I'm already tired of messing with this building and I haven't even cleared the land to put it on. On the other hand, it is starting to cool off, and this has been one hot summer . . . so maybe the wait will actually be worth it in the long run.

One thing I have definitely learned from this experience: metal building salespeople are closely related to the vinyl siding folks that call you in the middle of dinner. They won't ever see me again.

BillyDoc

[mydauphin]

Dude, why do you need such a permanent structure. My boat is in yard next to Jones Boatyard. Whenever they get a mega yacht to paint, they just get a aluminum Structure like a big hanger and cover it with something like shrink wrap. They put ac and everything inside. I would have build something for my boat, but it was 72' long and 20 foot wide and 30 feet high. You can build a simple shed out of 2x6 and cover it with plywood and waterproofing material. Give me $20k and it will be built in a week. Seriously, I don't know what building code your working with there but you might be able to do something less permanent.

On engineers, I build seawalls for a living. I just fired one of a project. It was going to take 500 yd of concrete. When my foreman saw it, he said, "this piece of crap wont work, it will sink with pilings" and you know.. he is right. So fired engineered, hire new one that will design wall will mini-piles. Save the concrete, forms and about 30k on project. I think my old engineer worked for DOT and thought he was building a interstate highway.

[BillyDoc]

Mydauphin,

That would work . . . for a while. Just until some bastard trying to steal himself a deer discovered this treasure trove of tools way out in the woods with nobody around and nothing but plastic sheeting between him and them. I've already had problems like that, and I plan some nasties should they happen again . . . but I'd rather the tough building just keep them out. I can't be there all the time. I'd rather build in Pensacola and I have enough room in my backyard, but if I do then I pay taxes like you wouldn't believe for as long as I own the property. If I build on our tree farm, then it's agricultural and a bunch cheaper.

I'd rather be in the woods anyway.

BillyDoc

[mydauphin]

The first rule of boating and boat building
KISS....
Build a strong shed for tools.
A shelter for wind, sun and rain
Good Power and Water
and cheap because your boat is going to take a lot longer and more money than you think.


P.S. My boat is on Miami river full of pirates and crack addicts.
I have lost a generator and a water pressure cleaner, in two occasions. They cut chains, locks and busted a door. I consider myself lucky because neither was death blow. Hurricane Wilma blew $3000 worth of ALuminum Plates into river was able to recover half. It crinkled aluminum plate like foil paper, had to use sleg hammer and pickup truck to get it straight. Such is boat building... You never know what your going to go through.

[BillyDoc]

Damn Mydauphin,

At least it's not THAT bad here. But this is where I'm going to leave everything I own when I'm out sailing . . . and I have a LOT of tools. Some of which are very expensive. So . . .

Security through obscurity, and
Security through brute force, and
Security through trickery and general evilness.

There's also a very nice spot on my property to just sit and enjoy nature for a while by a spring. I gave the Sheriff a key to the place several years ago and invited him in any time he wants to nose around or just take a break. That cut my problems with thieves down a lot!

I lived in a civilized country once, where there just weren't problems like this. I miss it.

BillyDoc

[korvello]

BillyDoc hi: regarding my comments afterwards i realized that maybe you're building with those one piece curved panels or so and maybe my comments wouldn't aplly there if so i'm sorry ........ a set of plans up here from scratch will run less than 2000 with the engineer,sometimes as low as 1400 , i just don't know if the requirements are the same in florida ,but it shouldn't cost that much to find an engineer down there to review the plans and sign over and correct what you think it's wrong and may even save you money compared with what you have now.....regards

[mydauphin]

Engineering should not be a big expense. Try my ....friends at Engineering express. http://www.engexp.com Frank Bernardo is a good guy. I never get a bill more than $800. Tell him tony from Dauphin Marine sent you.

[korvello]

great deal Tony ,could use it myself...BD what is that about building a 3/8 hull and leaving your possessions abandoned seems like gamblig to me i think you have better odds going out in a fiberglass boat than not be robed if someone is not around specially in the wild ,a welded shut sea container my help butt i wouldn't take either risk ,getting someone to live for free or low rent in my property is how i intend to do it.....regards.

[BillyDoc]

Mydauphin and korvello,

Thanks for the advice, but at this point I just don't want to mess with it any more and will be going with what I have. I'll be buying more concrete than I need to, for sure, but at least it will be strong . . . and I won't be waiting another couple of months to get started.

I got a path cleared this morning for running in the power. I'll be trenching it and laying in conduit which the local power company is providing, then they will come in and pull in the feed line to a ground-mounted transformer.

It felt like progress! But I sure need a shower now.

BillyDoc

[korvello]

Good for you BD i hope all goes well. ..hope you don't mind using your tread to ask Tony if he knows about a cheap/reasonable boat designer-arquitect-engineer , if you do Tony i would greatlly appreciate any leads;thank you both.

[mydauphin]

Dont know any boat designer, architect... etc... I do my own and live with consequences.... ha ha . But there are many online and a few based in Mobile Alabama area, Miss and Louisiana. What kind of boat your looking to build?

[korvello]

Thank you TONY ; do you use a software program or the old fashion way? ...I design myself and have already most of it on paper i was just looking for an experienced guy to review it ,do some calcs and putt it on the computer maybe even do a couple renderings ,an arquitect friend says he can do them on FORM Z a cad program,but i would still like to talk to a naval engineer or somebody with some experience on the field ,i had to learn a lot on the building industry the hard way , paper arquitects and engineers are a dime a dozen on the left coast.

[mydauphin]

Korvello, I have built or rebuilt at least 20 boats in life. My first boat I believe was when I was 12. My trick is following successful designs and just tune them to my liking. I am not putting down many architects or designers, but many dont have the time to do a good design from scratch. I rather get a hull from bertram, chris-craft or whoever and make it better for my use. Then I spend alot of time fine tuning weight distribution, propulsion, etc... I dont get things right most of the time the first time. But neither do the guys with all the computers either. I treat boats like race cars, alot of trial and error.

I will not buy a new boat any more. I look at them and get upset. They are all lacking engineering, strength, ease of access, reliability , are inefficient and have too much power and don't carry enough fuel or water.

So seriously, I would buy a old good hull cheap, And work from there. You have a baseline. Then improve the boat to your needs. I leave interior layout and design for almost last. I just build interior as needed to fit things like electrical panel. I try to optimized boat design to usage. I work in broad strokes first and then work into detail as it goes.

Sure this method is not very efficient, or commercially viable but allows me to fix design mistakes in real world. Why build a design in computer then to realize the bathroom door wont close. I never know where I am going to put toilet until bathroom is built. Sounds simple but in boat bathroom an inch is alot.

Your probably asking, what does this have to do with boat design.
Unless you have built a 100 boats in your life from start to finish, it is hard to predicate boat weight. And if you cant predicate weight, then how can you predicate how your boat lays in water? Can you predict how much fiberglass is going to weight? Computer is starting tool but when you put boat in water that is reality. Same goes for props, rudders and heavy items like fuel tank.

Of course, the smaller the boat the easier. I would start by building a 12 to 14 ' Skiff type boat. It will teach a lot. Copy a simple design like the original Carolina Skiff. One of the things your going to learn fast, it is cheaper to buy a used Skiff and fix it than laying glass yourself...

I would love to see your design, and I will give you a honest opinion.... for free... lol

[Jimbo1490]

And I am well aware of the disaster it portends. Oh, well, our species just insists on consistently doing the stupidest things possible, like in this case destroying our collective home for individually selfish reasons.

As already stated, the northwest passage has been open before, without any help from 'evil' humans. Is it not at least possible that it is opening for the same reasons today?

When the earth was considerably warmer than today (within recorded history) it was a time of peaceful weather, abundance and prosperity. But of course, this is not as newsworthy as doom and gloom :D

Jimbo

[korvello]

thank you TONY,very interesting aproach ,i've used the same before while remodeling or building houses ,now i can just tell what works or not without building it but it sure took a lot of trial and error and continuous last minute changes..................i'm building "my boat "not an experiment or learning cannoe i intend to go away for large periods of time , it will be a catamaran minimun 26 by 52 with a few original ideas; i will have some basic renderings hopefully soon and i'll submit them to you and maybe the open forum ,quite a lot of experienced guys here on the forum and i love debate and explore new points of view i'm sure i'll have a lot to learn and bugs to fix, that's why i'm picking your brain can't beat hands on experience of guys like you, once again thank you for your time.

[bengomez]

You need to investigate "english wheel". We hand formed compound curve sections on 53' round bilge aluminum hull. I
have photos. You could build one yourself. For forming aluminum I don't think you'd need hardened steel rollers. Industrial "caster type" wheels would do. It's surprising how little pressure is required on the wheels.
I agree with that man, yeah industrial caster type wheels would be...




_________________
blanchard grinding (http://www.preciseplate.com)

[Jackphilps]

TIG weld the seams?????????? wot on earth

[Guest62110524]

lot of funny stuff being written here, one big no no, never tig seams butts, distortion is immense, mig at high speed
i use poly formers for forming, thats why there are no marks outside, the stretching is on inside where the heavy marks are
these are part of my book so scuse text

[Ad Hoc]

Jackphilps
Just read your comment had to laugh, and so I looked back. I agree...but which is worse, TIG welding the seams, heating the plate or forcing into place...unbeliveable what seems to pass as "acceptable ship/boat yard practice" for many!!!...and they wonder why aluminium gets a bad name!

[SteveFid]

BillyDoc, I know your post is pretty old (from 2006)... Did you ever make a heavy duty wheeling machine? I am looking for help on building one. I want to form very heavy stainless steel plate (3/8" or even 1/2") and the wheeling machines I have found availible so far are too light duty. I would appreciate any help you could give me as far as plans you may have. I would have my engineer buddy help me beef up the specs on plans to handle the load I would need.
Thanks,
SteveFid


Thanks for the link, John. You need to edit it to add .html at the end though.

The pictures of the large "commercial" machine are very interesting. I am becoming more convinced than ever that this is the way to go . . . and building a wheeling machine doesn't look that hard to do at all!

Compared to building a yacht building the machine to use seems downright simple, actually.

BillyDoc

[BillyDoc]

Hi Steve,

I still haven't been able to build that machine, the little economic downturn we seem to be experiencing here has made it darn near impossible to sell property . . . which is how I need to pay for that project. So, I'm basically waiting and polishing my boat plans. I did get some contract work recently, stimulus money from NASA actually.

Anyway, let me share my thoughts on the subject, in case they help.

I will (I hope) be rolling out 3/8" aluminum, so I did an experiment to try and get an idea of how much force would be required between the rollers. Once you get that number the rest of the design follows pretty easily. For the experiment I modified a hydraulic shop press by tapping into the high pressure side in the bottle jack that it uses for power and adding a pressure gauge. I measured the jack's piston diameter and did the math to see how many square inches were there, and as it turned out my particular jack had exactly 3 inches of piston area, so the pressure I read on the gauge times 3 is the pressure the shop press is applying. I next made a tool with a surface similar to the upper roller I intend to use and applied pressure to a scrap of aluminum similar to what I wanted to form. I say similar because this scrap was 5052, and I will ultimately be using 5083 . . . but I doubt there is much difference for the purposes of this experiment. When my tool indented the aluminum to a level I guessed would be sufficient for rolling, I noted the pressure. In my case that came out as 6,000 pounds. So, now I know pretty much all I need to know to design an English wheel. My roller bearings have to be able to support at least 6 thousand pounds, but I will add a safety factor to that of at least 2, so 6 thousand on each side of the axle.

Your engineering friend will be able to calculate the stresses in your frame, or you can download a copy of "BeamBoy," which is free, and do it yourself and just make it as strong as you like using conventional structural members like "I" beams, etc.

I do think you are going to have some special problems with stainless steel though, depending greatly on the particular alloy you are using. Most stainless steels "work harden" very rapidly. This is why when drilling SS you are better off drilling slowly, but with an aggressive bite (a lot of pressure) so you can get below the hardened area when the cutting edge comes around a second time. When trying to roll the stuff you are going to make a hard surface on the first roll, which will probably crack on the second. On the other hand, I know it's possible to do it, just not the technique. The reason I know it can be done is that I occasionally use large SS tank heads to make things out of and these are often rolled to shape, "spinning" them over a form actually. Since I can purchase these in 304 and 316 with no problem, it would seem you can at least shape these. The last one I used was 3/8" thick, by the way. This is a total guess, but I think the trick is to apply enough pressure on the first pass to not need a second. You might try Google or youtube with "Tank Head" and "forming" or "spinning" and see if you get any clues from that.

As for the actual design, take a look at Whoosh's post above and you will see a nifty design where the rollers are oriented so that the metal goes between them vertically. This makes it possible to hang the metal from something and swing it back and forth between the rollers, getting the weight off of your own personal muscles. Another thing Whoosh does is use urethane-treaded castor wheels (or something like that) for one of his rollers, and avoids messing up the surface that way.

Finally, I plan on using hydraulic motors for power, possibly driving the lower roller with the ring gear and pinion from a scrapped truck differential. This, of course, depends on what you can find when scrounging.

Hope this helps, I can't think of anything else at the moment.

BillyDoc

[SteveFid]

BillyDoc, Wow this is great information. Thank you so much for taking the time to give me this info. That is pretty cool how you did your test. I know I can wheel the stainless steel. I know there are companies that do compound curves in 1/2" thick stainless steel. I called a company to have them roll some stainless for me and they told me they were booked out five years and could not help me. Attached are some pictures of compound curves in stainless steel. Thanks again for the help. Steve

[jonr]

Not cheap for low quantities, but hydroforming would do a good job.

[SteveFid]

jonr, how do I use hydroforming when I do not have a cavity for the fluid?

[jonr]

The mold creates an entire cavity. But it could well be that it isn't applicable to the design (welded plates) you have in mind. Or that a brake press makes more sense.

[Bigfoot1]

1/2 inch plate is much too heavy for what you need if you are putting in transverse and longitudinal frames. no need, and harder to work with.

You should consider getting Tig out of your process. Tig imparts much too much heat into the HAZ, heat affected zone, weakens the joint and will put permanent deformation into the hull. Ie you pour on the heat, the aluminun expands from the heat, deforms, then you glue it together with the filler, and in essence you have welded in the deformation.

I know of no aluminum builder in the northwest that would consider tigging an aluminum hull due to this issue as well as speed.

If you decided to use 1/2 inch plate, you may have to make multiple welds which imparts even more heat.

In 1/4 inch plate, when we build our hulls, we start in the center of the boat and work out. Alternating side to side to allow for cooling between welds, start a weld, weld say 16 inches, the go to the other side of the boat, opposite location, weld that, then go kitty corner, do the same.

We have a manufacturing facility and I have about 5 guys using tig 8 hours a day, but we never would ever, did I say ever, put a tig torch onto a full sheet of aluminun on a hull.

You say quality of the weld is better with tig, sort of, it looks better, but there is no porosity in a mig welded weld, unless the operator is bad.

summary, 1/2 inch is too heavy, others say the same, follow their advice and leave the tig process out of the equation for the hull,

and consider 5086 h112 as the material for the skin,

[alumar]

Take a look at these boats, one built in 1/4" Al 5083 and the other built in 4mm Domex 550 MC high strength steel. The steel hull was built by a builder who had never built in steel before. Only if you look at the hull very well will you even recognize that she is a radius chine design and not a round bilge. Advantage is that you only need a normal rolling machine. There is really no need to go thicker than 6 mm on Al 5083 but if thicker plate is preferred, go thicker. If you can roll it, you can build it.
Too much welding on a radius chine? Do the maths and you will see that the amount of welding required is very similar to what is required on a multichine hull.
On welding: If Mig is good enough for the pro who builds to Lloyd's, it's good enough for the home builder.
Here one of the best and most detailed metal boat building sites I have ever come across . http://www.odysseyyachts.com/Odyssey_Yachts/BUILDING_BLOG/Archive.html
What Brian's pictures prove is that with a pre-cut kit a home builder can achieve outstanding results within a reasonable time frame.

[Bigfoot1]

BillyDoc
Your experiment that gave you a value of 6000 pounds to design an English wheel is incorrect.
The English Wheel works on the principle of producing very small local stresses
in an extremely small area to, ( I hate to introduce a new term) micro deform
sections of plate to produce a curve.

Some theory.

If you have 100 pounds acting on 1 square inch, the stress 100 psi, then if you reduce the area to one half inch, then the stress becomes 200 pounds per square in. ( or 100 pounds per 1/2 square inch) and so on

When you put a cylinder or a sphere and lay it on a plate, the contact area is theoretically infinitely small as only the outer most part contacts the plate.
In a cylinder, there would be an infinitely small line and the sphere, there would be a point.

Lets work with the Sphere

You put a load of 10 pounds on the sphere and the area is infinitely small. The plate underneath, deforms a bit and say that the contact area is .001 square inches
So the load is now 10 pounds divided by .001 square inches or 10,000 pounds per square inch.

So when you run a plate through an English wheel, with very small loads, in pounds, you can get extremely large stresses, in pounds per square inch.
And the deformation is done on a very very small localized area.

In summary, what you did the test on does have any bearing on the loading that it will take to build an English wheel
Cheers

[Guy Brown]

I have just posted my English Wheel for sale. See the Marketplace.
Thanks
Guy

[Stumble]

Billy,

Instead of messing around with this yourself you might want to think of calling Trinity Marine in Pascagoula (i think, near there at least). They make aluminium superyachts and I know they are really slow in the yard right now. They just might be willing to give you access to the yard for an afternoon to bend what you need, or at least tell you where they get it done at.