opening up the fer-a-lite debate again...

Discussion in 'Materials' started by tugboat, Sep 1, 2011.

  1. tugboat

    tugboat Previous Member

    ok ill just say it with a video..here are the links--http://www.youtube.com/watch?v=egp1_ypxNlk



    http://www.youtube.com/watch?v=4Z8Y-kPq9Cs&NR=1

    its me tugboat, im showing the results of some "grassroots" destructive testing...btw--im enrolled at macnaughton school now: gonna get my n.a diploma then still do what i do without the numbers game. pure intuition is still better than your computer rhino

    here are the links--if you like fal--or you hate it--you'll enjoy these vids...

    test slab- 3/4 inch thick 8 layers of 1/ 2 inch hardware cloth. 1/4 inch rods spaced about 4 inches apart..no matter what i did i could not penetrate more than one layer. when i used a welders tipped hammer for chipping, not the angled hammer--it finally broke through the skin...this was after hit after hit after hit--it finally failed but needed to be a sharp point and a hell of a lot of force behind it...i have no drothers using this as a building method--its half the price of steel and in my opinion-only marginally less stronger than steel.. cost vs strength between steel and FAL--FAL wins hands down!!! btw a simple barrier coat of epoxy seals her up but there is also a binder in it to make it waterproof...but to make it even stronger--a layer on each side of this slab of fiberglass cloth would be the strongest composite ive ever seen- might even be good for ice work...
    http://www.youtube.com/watch?v=egp1_ypxNlk
     
  2. Wavewacker
    Joined: Aug 2010
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    Wavewacker Senior Member

    Looks to me to be tuffer than 1/2 plywood. The only thing I know is that after looking at used boats, all kinds and price ranges under 200K, those made with ferro are much cheap than wood, much, much cheaper than glass and much, much cheaper than steel or aluminum for the comprably sized boat. You get a very inexpensive build and a very low resale value. I would think that the advantages of being better insulated, easily repaired and tuff skin could be a real advanatge builing a boat of 40' or more and one that would be a keeper and passed on to the executor of the estate for diposal (or the kids).
     
  3. PAR
    Joined: Nov 2003
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    PAR Yacht Designer/Builder

    The choice of hull material makes up about 10% to 15% of the over all cost on a 40' yacht (except for aluminum and fancy composites), so selecting cheap and difficult to resell materials for the hull shell is an unwise investment, particularly considering the impact on the total project cost and resale value.
     
  4. tugboat

    tugboat Previous Member

    I think it all depends on who is buying the boat Par, if the personm knows the material at all..or if they dont...

    --these days -at least in my area--doesnt matter what material the boat is made with they aren't selling..sadly thats the truth of it ...I also think that this may still catch on, maybe in the next few years. It will sell for better than ferr-cement im pretty sure..of course there is no way of knowing--but for a home built boat. the boat is usually for the builder anyway...of course a homebuilt boat is never going to come close to production boats as far as cost and buying a used one...

    I think for me the tradeoff is i get what i want at a decent price(it is still not cheap to build with it but half the costs of steel these days). I think multihull-maybe a cruiser that has a balance of speed and toughness would be good for this material, or any cruiser hull..if a workboat--steel is better--but of course its much more expensive too...
     
  5. Landlubber
    Joined: Jun 2007
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    Landlubber Senior Member

    tugboat
    stubborn rebel

    ...sort of says it all eh....mate, you seriously need to look at historical figures for comparative resell prices, ferro has been the lowest re seller from day one.
    Don't get me wrong, ferro certainly has its place in the game, dumb barges being one of them, they have stood the test of time certainly, and I was going to buy a Dutch barge (had a BRAND NEW Gardner that was worth 4 times the asking price) too to make a floating home at my marina, but that was nicked by a fella I was talking to at smoko, ******* went off and stole it from under me.....such is life.

    You really need to look at the build costs of boats, as percentages of the products used in the making. As PAR says above, the hull cost is quite small in comparison to the overall cost of the build, and labour costs HAVE to be incorporated whether you build for yourself or for someone else, as your time could have been spent MAKING money instead of spending money.
    The resell price, the real monetary value of a boat, will be less by a lot more than the percentage of the build save cost of using the ferro material.

    Having said all this, it is your life , your money and your boat, so do what YOU wish in the end, it just saddens me to see people do the wrong thing by themselves some times, and being a boatbuilder that spend every day these days doing repairs and restoration (cos there are no new builds), I see a lot of sad cases indeed. Most yards have a section dedicated to them....funny thing, here they are almost all east europeans, lovely people but "stubborn rebels".......all the best.
     
  6. tugboat

    tugboat Previous Member

    hey Landlubber--- did you see the vid??..not ferro-cement--that would have shattered and spalled...yes lower resale value perhaps, but i have the time.I dont plan on building it and a year later selling it -i plan on using the difference in price then selling it years later. I guess i figured seeing the strength of that would convince people...on the vid i mean...

    one thing i did wish i had was actual stats on the compressive strength of this at 3/4 inch thick..this vid shows the impact strength which is considerable. guess i'd like to try compressive strength yield but not sure where to start with that...
     
  7. pdwiley
    Joined: Jun 2008
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    pdwiley Senior Member

    I don't watch youtube videos, not enough bandwidth.

    Try that test WITH the cloth/wire and WITHOUT the FAL. What happens? Can you penetrate it?

    Do the same again WITH FAL and WITHOUT wire etc. What happens?

    Do the same again using a good Portland cement mortar. What happens?

    Trying it with the wire sandwiched between woven f/g and epoxy putty (thick goopy mix) would be interesting.

    I don't know what would happen but as a retired scientist I can say that all you've got is one datum point, you're guessing as to relativities. A good start though.

    I don't know how you've calculated the cost and strength WRT steel plate. Currently I can buy a 1800 x 3000 x 4 sheet of steel for $208. I paid $250 when I bought mine (sob).

    Are you going to fair the outside? If so with what and what's your time budget?

    There's NO WAY it's going to have the abrasion resistance of steel so forget about ice breaking. Point load impact resistance isn't the issue there.

    The resale *is* going to suck but as long as you accept that up front there's no reason not to do it anyway. I have mentally assigned a residual value of $0.00 to my boat so when I eventually sell it (or my heirs do) any return is a plus.

    Keep experimenting, you've got the time on your side.

    I did see your other post but I haven't taken any new pix for a while - lost the camera in the clutter somewhere. It'll turn up sooner or later. ATM I'm making small parts - mooring bitts, chain plates, through-hulls etc. I'm going for bolted through-hulls on 'spool' type standoffs for ease of future removal. Making them has been a bit of a PITA actually.

    PDW
     
  8. PAR
    Joined: Nov 2003
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    PAR Yacht Designer/Builder

    On the North American Continent ferro has a lousy resale value, but this isn't the case in Europe and Australia. Still, even in these other areas of the world, ferro is at the bottom (or near) of the resale value column.

    This is partly driven by the cost of accurate survey and difficulty getting certifiable repairs. Insurance companies need assurances, before they'll sign off on a claim or policy. This drives the value of the build method down. In areas of the world where they didn't suffer the indignities of Samson LTD, like North America did in the 70's, happy owners have managed to keep resale values higher. Unfortunately, this aspect of the data trail isn't easily justifiable, particularly by the pencil pushers at the insurance companies. The insurance companies aren't the evil empires they might seem. I do a fair bit of work for them and their concerns are justified and the sales, survey, repair and damage records reflect these very concerns.

    So, when someone pushes a medium, even a freshly tweaked version, the same data comes back to the surface and understandable concerns are raised.
     
  9. daiquiri
    Joined: May 2004
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    daiquiri Engineering and Design

    One objection to the method: hitting it with a hammer does look like a harsh test, but if you hold the hammer in your right hand end the plate is hanging freely in your left hand then your body movements and elasticity will absorb a big part of the impact energy. Try to repeat the test by laying the plate down on two hard and fixed blocks, wedges or similar placed beneath the plate's extremities, and then hit it hardly with a wide vertical swing from above. The outcome might be different.

    Before my next consideration, let me say that I have no experience whatsoever with ferro-cement, so sorry for a possibly dumb question. What really impressed me in that video is the structure of the plate... A lots of metal wires, tightly entangled between them. The question is: how do you repair that mess in case of any bigger damage?
    Say, a deep dent due to going over the rocks, or even a tear in the metal structure of the hull? Doesn't look like something easily repairable to me. But, once again, I have no experience with fer-a-lite so I might be completely wrong here.
    Cheers
     
  10. tugboat

    tugboat Previous Member

    Hi daiquiri, yes - i did think of that- after placed the slab on a flat concrete pad. the hammer inmitially bounced off---then after repeated strikes it did start to crumble. after many more blows i removed some of the first layer of mesh and FAL, after continuing this for about five minutes i did have the hammer almost through the mesh...in the video i do mention this situation of absorbing blows. however the matrix in itself does absorb the energy of an impact, and is designed to do that from what i understand. also-repairability--after i did this- i replastered the spots i had broken up. i should have posted this video too.because it looked great -you could not tell it had been fractured and there were no holes--the fix took about 5 minutes and about 1/4 of a quart of resin and a small amount of FAL...after this i hit it again to make sure there was a primary bond to the slab..it withstood the same abuse. on a full hull it would take a lot before it holed...thanks D.
     
  11. tugboat

    tugboat Previous Member

    hi par, yes I did exaclty what PDwiley did and assigned a 0.00 dollar value to the vessel so whatever i get after i use it is pure guava! Im well aware of the histroy of samson and insurers issues etc. one thing - many third world countries have built fishing vessel using standard fc conctruction as im sure your aware of--they have stood a testament to the durability of this method--to me its a shame the resale value is lower-but dfor those vessels they pay for the boat in a short time with the fishing income. But i dont know if this would be classified as a "ferro" type build?? the material is much different and if i did it the way the company suggests-its a different steel and mesh matrix....I get what your saying--because how do you know if there are voids during plastering? this would weaken the hull and water could get into armiture--but the nice thing i liked about this is you cna just do a bit at a time--contrary to other reports poly does an adequate job of bonding to itself--many good boats were built with poly. the blistering effect does not happen if the hull is sealed with epoxy. as they (samson) did to ferro cement hulls. but you are correct they will have a lower resale value--this doesnt really bother me much-but i guess if this was a business and i was ,marketing it--then it would be a different story...i just want "my "boat"

    next thing i need to know is empirically what kind of compression yield we are talking on it...
     
  12. tugboat

    tugboat Previous Member

    Supposedly this system-thread- is telling me that my message is too short--ive been having problems with writing in the thread for some reason...
     
  13. tugboat

    tugboat Previous Member

    I think I have to agree there--thats the trade-off you are quite correct- low build costs=low resale. high build costs=high resale. of course this also depends on the boat-the craftmasnhip-the care taken etc...I like it because
    1. its cheaper than steel(costed this out with quotes from suppliers on the materials)
    2.its stronger than standard fg construction and it will last. my first choice is always steel...of course. especially for what i am building.
    3.round bilge type/compound curvature hulls can be built easily..this is a real plus for me.and i haven't really spoken on this before here but aside from costs the major reason i prefer this to steel is the ease of the build physically.
    4. im not a fan of chined hulls...just my preference for complex radiused or round builge hulls makes this an ideal material
    its not the best for chines. but can work well with beefed up reinforcement at the chines.
    5. my back just cant take steel builds anymore--the lifting -moving the welder, the setup--it is backbreaking to me...sadly i still love steel
    6. its not a really hard skillset to use. relative to other types of construction-(and after having built a wood boat-wood is by far the most skilled of all types in my opionion) i.e. to getting good reliable welds(x-ray worthy if in a pressure hull) etc..or laying up a composite -corecell hull for instance.


    cheers!
     
  14. pdwiley
    Joined: Jun 2008
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    pdwiley Senior Member

    Actually ferro has lousy resale value here too. So does steel but not so much. F/g seems to hold its original price best. Whatever.

    I'd only buy a ferro boat for the salvage value of what's on it. It may be wonderfully built etc but without taking x-rays of the armature how are you ever going to know?

    Not that it can't be done well, lots of solid and sound boats out there. I got talking to a man with a 15m ferro Colin Archer type he'd built in the UK. He'd been sailing it for the last 18 years and it was fine.

    Tug, if you *do* use FAL, take *lots* of photos showing ALL the armature layup and the plastering process. This will help convince people (surveyors for insurance companies etc) that it's been done right.

    Be interesting to see how long it takes you to build the hull using FAL.

    PDW
     

  15. tugboat

    tugboat Previous Member

    when i build it--ill document it all. I can be the first to admit--its going to be a long build--i have some things already..as mentioned before. No quesiton it will be a more labour intensive build. and longer than steel would --
    btw didint know you were a scientist pdw...or maybe i forgot-but what area did you do work in?
     
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