CNC Plans not Included

I just read this on the Farrier site

"A Note Of Caution On Building Methods: There are now quite a few builder's websites available on the internet, and some very advanced methods (infusion, vacuum bagging etc.) and materials are being used. However, it should be noted that such methods or materials are not necessary, nor are they specified. Plain old hand laminated fiberglass still works fine, and that is how I would build my own 'one off' hulls. Infusion and vacuum bagging can greatly improve the final result, but frequently one is only talking about a few kilos saved for what can be considerable extra work. Flat panel bulkheads are the only thing that I would vacuum bag, but, again, this is not necessary. However, once vacuum bagging is tried and experienced, it can be hard not to want to vacuum bag everything, as it does work so well.

The option is there for some very advanced and sophisticated work, if wished, but always be aware that the extra expense and time necessary is probably not worth it for most.

The hulls should be quick and easy to build - don't make it more complicated than its needs to be. Hulls are actually only a small part of construction, with most time going into internal finishing, assembly and fitting out. Spend too much time on the hulls and the boat may never get finished."

RW

 

But alas richard, there is still so much misinformation on the net...

Both Jorge and I have already mastered resin infusion. You may have missed his build thread on the last boat he built using infusion and flat panel methods etc... Infusion is not as hard as many people on the net make it out to be.

In fact, i found flat infusions much quicker than hand laminating provided you do big areas at once, and the results you get do not require any filling on 1 side, so you can take it straight to paint! So, there is more savings there on top of the laminating savings!

Cost. People dont undertand that if you avoid the expensive consumables that the composite suppliers profit from, infusion can also work out cheaper! I found it to be quicker AND cheaper... so did Jorge...

But How??? reason - The reduction in resin consumption more than pays for the consumables (sourced from the big box hardware store not composite marine ripoff merchants) compared to hand layup. I have a spreadsheet which proves it.

With a bit more creative thinking, you can improve it further. For example, i beleive i have a method of infusing all the panels for a large catamran build in 1 shot. Probably take 4 days or so, every panel in the entire boat done, full length panels. Cut out the smaller peices from the huge sheets. All sheets pre marked via a tiny 1mm surface score via CNC router. Cut out the finished panels using the scoring as a guide. The restriction is the design must be all flat /developable surfaces. The labour in assembly comes from all the secondary laminating. Every fillet and tape join, there is hundreds of meters of it. The mold method reduces that part...

Im not sure whether it would be quicker to simply build a big mold like jorge is thinking of, or just get cracking on the flat panel method, i really cannot say which would work out faster all things said and done?

Either way, its still a shed load of labour and you simpyl cant beat having an abundance of workers to divide those hours up...

 

Actually I only posted that quote for the last paragraph

RW

 

I would add that infusion lets one avoid exposure to resin and is much less tiring. As for results, it lets a solo inexperienced person get as good of results as a pro laminator. Otherwise, inexperienced people don't do anywhere near as good a job or move as fast. I would add that I don't really trust so called pro laminators to do a good job either because I suspect cost cutting has eliminated many of the long time pros.

But it's not just about the actual laminating ... The time and energy required to flip, re-laminate, re-position, and then hoist the bridgedeck, check alignment again, shore it all up and so on ... It's a lot of wasted movements that begin to add up. That is why I posted the link to the Schionning build, it's a concrete example, of a few people, some with experience, going well into the second year before they had the main structure built.

Infusing all panels in a stack in one shot as Groper mentions saves a ton of time plus all the consumables for individual infusions. I plan on doing this with all the smaller parts, anything that will fit on a 5 x 10 sheet of core. Then I just run it through the router no manual cutting needed.

One thing I noticed about my build is I hit a point where my enthusiasm was waning. Working every night till 10 pm and Saturdays all day started to make me less efficient. Once that mind fck kicks in, only a pit bull attitude gets you through. So I believe, having the main structure erected as quickly as possible also influences later work. No way to substantiate that, just my feeling from years of residential construction where we push extra hard to dry-in day and raise a flag and have a party when we get there.

Richard you mentioned it would possibly take over 100 hours to install a steering system. I assume you mean the cable system. I read about the options and believe in my case, not a purist, crossing oceans mostly on auto pilot, that I would use hydraulic and could install that in a fraction of the time, probably one day as it only took me hours on my powerboat.

So not just simplifying and eliminating stuff but picking systems that save time. Torqeedo is another such major system pre-engineered to cover all electrical use on the boat including drives, galley, lighting, all types of loads 12-24-110-220, genset etc... It's expensive but turning this into a plug and play solution saves me countless hours and lets me focus on expediting things such as pre cutting holes for chase tubes at same time bulkheads are cut out, electrical panels can be premade, mounts for batteries and so on ...

I also look it as Ikea but not in a negative way. Ikea is excellent, where they fail to some degree is in their materials that makes them less hardy. My biggest concern is also labor, we don't have a lot of people to pick from in the keys. Building out of the country, as mentioned, has the potential to backfire. I may just have to suck it up and plan for that extra cost.

 

The creative thinking has been done.
Cut the sheets (cnc or by hand) before glassing them so there is no glass dust or edge finishing,
Include landings in the hull infusion so there is no secondary laminating/filletting/tabbing,
Include the furniture in the structure/infusion so there is less fit out.
Use a non shiny mould so there is no sanding/polishing or waxing.
Make curves in one dimension and fold/bend the shapes rather than make them from multiple pieces which have to be glued, glassed and faired.

This is all done in Intelligent Infusion, along with a lot more. The composite part of the fitout and the manufacture of the hulls takes a fraction of the time required for conventional building. And uses less materials, resulting in a lighter, easier driven boat.

With Intelligent Infusion, we can build an 18m harryproa hull http://harryproa.com/?page_id=1177 with no trimming, sanding, grinding, secondary laminating or bogging. It includes 2 cabins, shower/toilet and the mast step and deck bearing, beam holes and local beefing up these require. see http://harryproa.com/?page_id=1327

True, but significantly less labour (maybe half compared to conventional methods) with Intelligent Infusion and almost none of it is strenuous, dusty or sticky.

Jorge,
Absolutely agree with your post.
Other areas where months of work can be saved are:
The rig. An unstayed mast(s) with wishbone eliminates the forebeam, striker, mast step, chainplates, traveller, furler, jib tracks, winches and all the alignment, beefing up, bolting and bonding that these items require. Plus their ongoing maintenance. The benefits extend to sailing which is far easier, safer and less stressful.
Propulsion: Instead of fitting outboard pods or inboard diesels, build a big tender and use it's outboard to power the mothership.
Leeway resistance: Fixed keels are inefficient, draggy downwind and added draft. Daggerboards and fixed rudders are a collision waiting to happen. Oversized, liftable, kick up rudders mounted inboard of the ends are less work, less drag, more versatile and much safer.

rob

 

The impression I got from your first posts is that by infusing the hulls you thought you would get a 50ft catamaran on the water very quickly.

What I have been trying to say (and obviously I have not been expressing myself clearly enough) is that it will still take a long time to finish a shell however it is built. And so what you need to do is look at the design as a whole and reduce build time for the interior and fit out as well.

So using the example I made last post, I think you will be lucky to install two tillers, a 25ft tiller bar, a steering console, wheel, engine controls, hydraulic hoses, autopilot and cover them all up neatly in a day! Assuming you already have the rudders fitted. But you could do it easily with a tiller steered boat

And, unless hydraulic steering has changed dramatically in the last couple of years most people who like to sail don't use it as it has no feel. They prefer cable

Like Groper, I have fitted out both sailing catamarans and power cats as live aboard cruisers. I think Groper will agree that a sailing boat takes way more time, never mind more money

RW

 

Your Proa is really nice. How is the racing one your building coming along. I wonder how unstayed masts would work on a regular cat? I especially like the less maintenance and cleaner look of an unstayed mast and time savings would be welcome!

Ok, I see what you are saying. Yes absolutely about looking at the whole boat. You will see a lot more posts from me as I learn of each of the different components and determine the strategy.

On the threads I read, it was almost an even split on who liked and didn't like hyd. steering. Those that didn't like it, hated it with a passion! My wish would be to be able to control the boat from multiple points like the Rapier 55. All the ropes run to the inside helm and are controlled by buttons from any of the other helms or tillers. I believe that must cost a small fortune though )) ... still I will look into it.

 

Yes rob, you've come up with some interesting concepts, I like what you've done. Unfortunately tho, not all shapes are possible with your methods and provided your happy to accept those shapes, then it's a great way to go.

If I were to build again I'd use a combination of ideas... some of yours in places, some of mine, some molded parts etc...

1 thing I'd like to explore via this forum is how to make finished bulkheads in 1 shot, complete with bonding flanges , and with curved edges for a round bilge type hull. I'm sure it's possible to setup on a table but with how much time? It's not that slow to simply cove and tape them in afterwards, I just don't like the finishing work which follows that...

I think alot of time could be saved if the bulkheads were completely finished before installation with only a MMA glue in required...

 

I think I understand what Rob is saying. Infuse the slot at same time of hull.

Those shapes are easy and fast to make. They can be pre-formed while you are loading the mold and then simply screw them on top of the main hull laminate and throw a couple more of pieces of laminate over them before infusing. The drawing shows laminate ending short, I would let it run 3 inches or so past slot

When you add the adhesive, your gluing to a glass face.

Alternatively you could mud the bulkheads in and follow with full length fillet flanges (top and bottom hulls) later but then you would have to infuse the flanges separately which would be more work. A story pole would allow perfect alignment with the top half of the hull. That's an easy fair job!!!

edit- Also the adhesive would be coved, not flat as shown, to the bulkhead. That looks like it would be a very strong joint and very little time consuming work. I would still infuse panels in a stack first and CNC cut, vacuum would take care of all the dust no problem and you would have a nice smooth edge.

 

if doing it on a flat panel on a table - i can see merit. If doing this in a hull, whilst its still in a mold, i see little advantage to simply taping them in afterwards...

If doing this with flat panels on a table - do they bend into the fair curve of a slender cat hull once this blocking is completed or will the hard spot create waviness in the finished surface? Might be ok if using female forma frames - cant say for sure tho?

The other drama of infusing in a mold - you still have to finish and paint the entire inside surface hull area whilst working in awkward positions with poor light and ventilation. This is the s**t id seriously try to avoid... You could line it instead? Finish all the bulkheads before installation, glue them in finished, and line the rest of the hull surface? i dont like the look of liners tho- carpet and the like goes moldy, other types of liners are heavy etc... you cant beat a faired and painted interior IMHO...

 

I don't understand what you mean.

Yes you paint bulkheads before installing. Just leave the glue edge unpainted but you also do the same with the entire interior of hull, just mask off the glue notches and spray the whole hull open. Fast and easy with plenty of ventilation.

 

If you think its fast and easy to fill and fair concave surfaces- then you must know some tricks I don't... Certainly better than all closed up but it's still heaps of work and dust...

(I used the good face of most of my panels facing the interior of my boat so i wouldnt have to fill them and do all that work inside. I figured it was much easier to fair the exterior of the boat rather than the interior)

My point is; im not sure if its faster to build with flat panels, and doing a taped seam build, finishing the panels for the most part on the table where its easier to fair/fill/paint them whilst they are flat on the table and easy to work. The panels can be infused with a caul plate on top, (or between panels in a stack) thus getting an essentially ready to paint surface on both sides of every panel. Assemble them in a female former as per a standard duflex build without the filling of the panels and the joining of small panels etc. Cutting them out is a very fast job - i reckon i could cut out the entire lot for a large cat build in a weekend if the panels were pre marked via thin line CNC in the foam core and had a helper to help move the big panels around the shed as we cut them out and stack em up...

The above method competes also with Rob dennys intelligent infusion method. Whilst his method is a little cleaner and doesnt require secondary taping, you will spend alot more time setting up each infusion as they have to done 1 at a time and with extreme precision. so theres more time there that needs to be accounted for as opposed to just getting on with taping it together with plain panels.

compared to, constructing a mold and infusing the whole structure in 1 shot. Alot of time would have to go into a huge mold and have it vacuum tight. Big job right there. Then once you have it infused, you still have to fair/fill the inside as you wont get a ready to paint surface -unless you have some more tricks up your sleeve? So you gain time in saving the secondary taping and fairing of the outside tape joins, but losing time in the setup and mold building.

All in all, i think the most savings come from the design itself - like rob dennys proas for example. Leaving stuff out is quick, as per RW comments...

I must be Mad... seriously considering building again :O

 

It is a little mad for sure, I should have said relatively easy. Sanding is one job that the help will be doing, not me. That said, it will be less sanding than on my little skiff!

I think you are misunderstanding on the notch.

They are shaped out of one piece of foam (drawing shows two because I rushed it). They get infused at the same time as hull, not individual infusions? They are screwed to hull core over inner hull laminate and are covered with a layer of laminate. No secondary taping needed for the notch or the bulkhead that slips in and glued with one of the approved tube adhesives.

I would align the notches with story poles that span the entire length of the hull so precision is pretty exact and transferable to top part of hull. We used to use a whole slew of these poles in 3d space for aligning complex curved stairways and landings. The care part would be carefully packing the bag into each notch under a bit of vacuum so they don't get misaligned when pulled down. I would lay the poles back over them outside the bag to check alignment as full vacuum is pulled. It's still one shot and not that hard to setup.

As for leaks, yeah, no way to avoid that for any method. I think buying the best quality bagging material is in order for the big infusions, still much better than infusing to core lol, omg that was a fn pain!

I agree on interspacing hard surface in a stack infusion, it would mean you have to feed from the edges of each panel using cut and perf core, no big deal on that I don't think but would have to test. You could even do that with the main bulkheads that span the bridgedeck. EDIT Actually not sure you would need those hard surfaces and are careful with the laminate, surface should be pretty fair, might be fair enough for simply using high build and sanding.

Very little fairing would be needed if you do all that. You save all the time of taping in bulkheads, in fact it should only take one day to install all of them. Already painted in an already painted hull... It's worth being MAD for one more build lol

 

Not so much fairing Jorge, but you have to fill the weave of the glass. Unless you infuse against something hard and smooth, there is always some filling to do, you can't take it straight to paint.... there's all the glass overlaps to fair out too.

 

Won't a heavy coat of hi build take care of that? Actually that has to be sanded too. Ok well then I guess liners might be an option.