Fiberglass and resin really stick to foam??

Canvas covered foamies (Thrifty Alternatives...)

Moderator: eaglesdare

Re: Fiberglass and resin really stick to foam??

Postby jimbo69ny » Thu Nov 22, 2018 7:36 am

GPW wrote:But … If you go Epoxy and Fiberglass cloth , surface preperation is VERY important , the foam must be sanded dead flat , ( long sanding stick) , and those little holes poked in there with the wallpaper perforator, really can add a lot to the overall skin/to foam strength as they dry hard ( epoxy) and are like little Nails grabbing deep into the foam . And while you’re at it , might as well put a decently Thickness of FG cloth on , because you’ll be sanding a lot of it off to get that Mirror finish . ( ask me how I know ) In order for the finish to be Perfect , everything underneath has to be PERFECT!!! It really does !!! … Paint doesn’t cover anything .. especially little finish imperfections …
Personally , If I wanted shiny , I’d forget the FG cloth and go with that FG board over Foam like Ken W did ^ … I saw that one up close ( I touched it !!! ) and it was really Nice !!! ( and traveled many Thousands of miles too ) :thumbsup:

Jimbo , check out the FoamStream Thread or my photo album … Sorry , we never did a Build thread or videos , as we spent all our time here convincing the folks it would work in the first place … :lol:

Fg board? Have a link?
jimbo69ny
Teardrop Master
 
Posts: 111
Images: 10
Joined: Thu Aug 09, 2018 2:53 am

Re: Fiberglass and resin really stick to foam??

Postby GPW » Thu Nov 22, 2018 7:41 am

We'll have to ask Ken what he used …. I couldn’t say … It did Look really smooth … 8) I’ll see if I can find him … ( be back )
There’s no place like Foam !
User avatar
GPW
Gold Donating Member
 
Posts: 14106
Images: 545
Joined: Thu Feb 09, 2006 7:58 pm
Location: New Orleans

Re: Fiberglass and resin really stick to foam??

Postby ScottE » Fri Nov 23, 2018 8:20 am

I used fiberglass tape (4" wide) and epoxy to strengthen the exterior edges (walls to roof/walls to walls/walls to plywood "pan"), and canvassed my trailer w/Tight Bond II. It has worked wonderfully! I did not poke holes into my foam, i just roughed the foam surface with coarse sand paper to break the "shine", and have had no separation issues. I learned about using fiberglass tape and epoxy building my boat, a few years back, and the two building methods mesh well.
137857
My Trailer weighs less than 1,000 lbs and has no structural issues after several years of service (you can see my build details under Camp Capsule Foamy.)
Best of luck with your build!
Anything is possible, if you don't know it can't be done!
User avatar
ScottE
Teardrop Advisor
 
Posts: 58
Images: 101
Joined: Mon Oct 13, 2014 5:33 pm
Top

Re: Fiberglass and resin really stick to foam??

Postby jimbo69ny » Fri Nov 23, 2018 8:27 am

ScottE wrote:I used fiberglass tape (4" wide) and epoxy to strengthen the exterior edges (walls to roof/walls to walls/walls to plywood "pan"), and canvassed my trailer w/Tight Bond II. It has worked wonderfully! I did not poke holes into my foam, i just roughed the foam surface with coarse sand paper to break the "shine", and have had no separation issues. I learned about using fiberglass tape and epoxy building my boat, a few years back, and the two building methods mesh well.
137857
My Trailer weighs less than 1,000 lbs and has no structural issues after several years of service (you can see my build details under Camp Capsule Foamy.)
Best of luck with your build!


Thank you so much for your input!! Ill check out your build.
jimbo69ny
Teardrop Master
 
Posts: 111
Images: 10
Joined: Thu Aug 09, 2018 2:53 am
Top

Re: Fiberglass and resin really stick to foam??

Postby KCStudly » Fri Jan 11, 2019 5:24 pm

OP827 wrote:... KC is building with glass and epoxy too. I am interested in objective cost comparison of two methods. I am not convinced that PMF is actually substantially cheaper for time and material than epoxy and glass. Both methods have pro and cons. Epoxy glass gives more rigid and better finish surface than canvas. Canvas are more user friendly and safer to glue, self healing under sun as some reported here. Both surfaces are equally easy to repair. If you decide to build, I would encourage you to do your own testing on scraps and decide what you like more...


Well, TPCE isn't complete yet, but I wouldn't say I didn't finish it... just not yet. :oops:

I did a bunch of experiments and found that epoxy does not work as well with cotton cloth as it does with fiber glass (FG) cloth. The cotton does not absorb the epoxy the same way that it would water or water based products; and you can't see through it when it is wet to see if it is fully saturated and stuck down; whereas with FG cloth the epoxy soaks in readily, causing the glass to go clear so that you can readily see that it is saturated.

Two plies of 6 oz cloth provides a very solid surface over foam board. I did a test panel of each (2x6oz vs. 10oz... or was it 12oz? IIRC 10oz... duck/TB2, both with mesh unfilled, no sealer or top coat). Surprisingly, they weighed exactly the same. When struck relatively hard onto the corner edge of my work table the canvas tore in a triangle and made a dent in the foam; the FG cloth bounced off and I had a hard time deciding if I could discern where the impact had occurred. I wanted better impact resistance so I leaned toward FG.

Contrary to popular belief, the FG... at least in this schedule (i.e. just two plies of 6 oz) is not brittle. My 12 x 10 inch test panel over 3/4 thk foam, now several years cured, can still be bent back on itself in a 'U'-shape and it comes right back when flattened, no discernible delamination and no cracking. I think this cracking myth comes from comparing catastrophic impacts of FG cars and boats to those of metal cars; yes, thicker schedules of glass are more rigid and will "break" when they fail, compared to metal cars that crumple and dent. Both would be considered wrecks, but the metal can be hammered out (before applying body filler!!!), whereas the FG needs to be repaired in a similar manner to how it was constructed in the first place.

In my area, at my local marine supply outlet I have been paying about $8 or $9 per yard of 60 inch wide 6 oz cloth (about 2x the cost of a single ply of 10oz cotton at the time I bought... and the prices on cotton are about half that now Big Duck 10oz cotton duck cloth, and the last gallon of West System with hardener was quite a bit more than my first, something like $130, pick up, no shipping. I must be on at least my 3rd gallon, but there have been a few quart containers here and there, too... and I'm not done filling the weave or fairing. TPCE is 64 wide x about 50 tall x 9'-8" long with 6 inches wrapped under the floor on all sides, not including the tongue box (TB). Add more $$ for fairing fillers, ratio pumps, a cheap digital scale (highly recommended) and alternate hardeners (you bought 'slow' but the weather turned cold, so now you need to go buy some 'fast' :( Don't worry, tho, your project will take longer than you think and the weather will change again :lol: ).

Remember, you can't use cheaper polyester or vinyl ester resins with polystyrene foam; and you can't use stranded mat cloth as a cheap buildup with epoxy, either (it has binders in it that are not compatible with epoxy).

The health hazards and inconvenience of wearing PPE are real with FG/epoxy. If you are gonna do it, do it right; no excuses and no cheating. If you don't already have and know how to use a proper vapor/particle respirator, plan on another $35 or so.

I use scrap sticks to stir with and save used Tyvek sleeve from work to protect my arms. Disposable nitrile gloves are not cheap and that cost can add up fast. My preferred mixing cups are cut down DD ice coffee cups; they do have a bump up in the bottom, so you have to take care when mixing to squeegee all around, but the are "free" (unless you count how much money you spend on their coffee!!! :lol: ).

On getting a nice finish: there is no "easy" way. If you want to do PMF and have it come out looking very nice and presentable you can do it. There are plenty of examples here. It will take attention to detail, special care and effort, and more material and time (surface prep, work place prep, plan your folds first and fill "jambs" before main plies, some people use jigs and fixtures to hang the canvas while applying, plan and execute your trims, folds and overlaps carefully, fill the weave, block it, fill some more, block it... do it again). Same can be said with FG. The nice ones don't just happen, they are created through hard work.

Rather than sanding through the structural fibers, the idea is to add enough filled epoxy ("thick") over the weave (or high build primer) so that when you sand it back you are not cutting into the strength by interrupting any of the long fibers. The smoother you lay down the glass (i.e. surface prep and care in layup) the stronger the cloth will be for a given thickness, and the less filler will be needed. Again, time and attention to detail make a nice job. Haste and slap dab make something fast and campable... and most people won't care or even notice, but the ones that do will. Some won't know why one person's creation doesn't look as nice as another, but the ones that do will shake your hand and tell you what a great job you did... or will assume you bought it from a factory. :lol:

I waffled in my planning and had already started using light weight vinyl ceiling spackle as a fairing compound to prep my foam for PMF. Then I changed my mind and decided to go with FG. If I had it to do over I would more closely follow the Rutan method, which IIRC sands the foam smooth and fair (remember, they use special grade foam... we need to at least take the "glaze" off), then apply a loosely filled epoxy coat before the weave. This gets a good bite on the foam and lets the cloth embed into the "thick". I prefer using the dry on dry layup method for larger surfaces, so I would do the loose thick over the foam, wash amine and sand to fair before the cloth layup. That way you start right off with a moderate hard shell. I spent too much time and material chasing soft filler and foam; it moves under your sanding pressure and expands/contracts with temperature changes. In the evening after my day job I'd fair a section of foam up to blocking or spars, etc. and come back on the weekend in the AM to find it no longer fair... move on to somewhere else and look at it again in the evening and it would be fair again. Get the foam "close", get the hard shell on, do the cloth layup... I found that working by myself on such a large project at a shop away from my home, it was not practical for me to do layups and weave filling all in one "wet/tacky" session, so I ended up washing amine and doing surface scuffs a lot... then fill the weave with thick thick... then find that thick thick wasn't thick enough and it slumped down a wall. That's where I laid the cabin on its side to do the side walls "in the flat", things got tedious and my project sort of stalled for a couple of winters. You can't use epoxy below 45 deg F, and probably shouldn't even go below 50.

Mind you I'm not even going for an automotive quality finish. I just want it to be relatively wart free. I thought about just leaving the weave, but once you have a couple of overlaps to fair or more heavily wetted areas, you end up with a mixture of unfilled weave and fair areas... too hard to maintain a uniform weave appearance.

What I'm trying to say to the OP, and others is, don't assume that you have to do FG to make it nice. You have to do a lot of good work to make it nice, whichever material you choose. And it will cost more than you think, regardless. By my estimation the typical budget overrun described by posters here is about 1/2 again to double what you thought. Don't believe me? Keep track of every receipt. Believe those who say they did it on the cheap (and they have a "nice" TD to show for it)? IMNSHO, they didn't keep track. Sure, there are people that can scrounge the right materials at the right time, or just plain have access to materials through their business or jobs, but overall, be realistic.

When in doubt, test. Do a small sample. Then scale up your test to something of moderate scope that can actually be used in the finished project, like a tongue box or a chuck box. Then decide.

I will finish TPCE. It will be the way I envision it. There will be things that I am not totally happy with, but it will be "nice" to my standard. Everyone should use the methods that they are best suited for and build to there own standard. There's plenty of room in the pool. Come on in!!! :thumbsup:
KC
My Build: The Poet Creek Express Hybrid Foamie

Poet Creek Or Bust
Engineering the TLAR way - "That Looks About Right"
TnTTT ORIGINAL 200A LANTERN CLUB = "The 200A Gang"
Green Lantern Corpsmen
User avatar
KCStudly
Donating Member
 
Posts: 9282
Images: 8117
Joined: Mon Feb 06, 2012 10:18 pm
Location: Southeastern CT, USA
Top

Re: Fiberglass and resin really stick to foam??

Postby GPW » Fri Jan 11, 2019 6:20 pm

KC , Oh don’t be so shy …. "but it will be "nice" to my standard. “ ... We’re totally confident It will be free Ken MARVELOUS !!! 8) :thumbsup: :applause:
There’s no place like Foam !
User avatar
GPW
Gold Donating Member
 
Posts: 14106
Images: 545
Joined: Thu Feb 09, 2006 7:58 pm
Location: New Orleans
Top

Re: Fiberglass and resin really stick to foam??

Postby tac422 » Fri Jan 11, 2019 6:25 pm

User avatar
tac422
500 Club
 
Posts: 596
Images: 222
Joined: Sun Mar 17, 2013 11:39 am
Top

Re: Fiberglass and resin really stick to foam??

Postby jimbo69ny » Fri Jan 11, 2019 6:27 pm

Thank you for the detailed writeup!! Excellent!

For what its worth though, I did have success using epoxy resin on cotton fabric. It was 93% cotton. It took more resin than I thought it would but it worked.
jimbo69ny
Teardrop Master
 
Posts: 111
Images: 10
Joined: Thu Aug 09, 2018 2:53 am
Top

Re: Fiberglass and resin really stick to foam??

Postby jimbo69ny » Sun Jan 27, 2019 6:55 am

I just did some testing

https://youtu.be/3NGJOkSH3T8
jimbo69ny
Teardrop Master
 
Posts: 111
Images: 10
Joined: Thu Aug 09, 2018 2:53 am
Top

Re: Fiberglass and resin really stick to foam??

Postby redbicycle » Sun Jan 27, 2019 10:11 am

Since the best out come was foam followed by cloth followed by map you could save some epoxy cost and epoxy and cloth the foam and top coat it with the map and varnish. You will get your UV protection that way also.


Sent from my iPhone using Tapatalk
redbicycle
Teardrop Advisor
 
Posts: 92
Images: 0
Joined: Sat Sep 08, 2018 5:38 am
Top

Re: Fiberglass and resin really stick to foam??

Postby jimbo69ny » Sun Jan 27, 2019 10:45 am

redbicycle wrote:Since the best out come was foam followed by cloth followed by map you could save some epoxy cost and epoxy and cloth the foam and top coat it with the map and varnish. You will get your UV protection that way also.


Sent from my iPhone using Tapatalk


Are you saying to not use fiberglass? I am definitely using fiberglass. Did you see how brittle the maps were when it was only resin and map?

I really dont like that it is going to bleed through. I think I am going to fiberglass, resin, dry, then sand, then take to an auto body place to paint. Its going to cost more unfortunately. I really wish the maps didnt bleed through.
jimbo69ny
Teardrop Master
 
Posts: 111
Images: 10
Joined: Thu Aug 09, 2018 2:53 am
Top

Fiberglass and resin really stick to foam??

Postby redbicycle » Tue Feb 05, 2019 6:14 am

No I'm saying use the epoxy and cloth(fiberglass) on the foam.


On top of that you can attach the maps with varnish. The varnish and maps will provide a UV protection for the epoxy.
redbicycle
Teardrop Advisor
 
Posts: 92
Images: 0
Joined: Sat Sep 08, 2018 5:38 am
Top

Re: Fiberglass and resin really stick to foam??

Postby jimbo69ny » Tue Feb 05, 2019 7:03 am

redbicycle wrote:No I'm saying use the epoxy and cloth(fiberglass) on the foam.


On top of that you can attach the maps with varnish. The varnish and maps will provide a UV protection for the epoxy.

That’s exactly what I was going to do except the varnish. The maps bleed through. Also, I am told epoxy resin inherently is uv resistant. It’s the polyester resin that will break down. Told this by Tap Plastics.
jimbo69ny
Teardrop Master
 
Posts: 111
Images: 10
Joined: Thu Aug 09, 2018 2:53 am
Top

Re: Fiberglass and resin really stick to foam??

Postby tony.latham » Tue Feb 05, 2019 11:40 am

Also, I am told epoxy resin inherently is uv resistant. It’s the polyester resin that will break down.


It's the other way around. Wooden boat builders have been dealing with UV issues since epoxy became available at a reasonable price.

Image

The sun will eat epoxy. There are some epoxies that are marketed as UV resistant but I have no experience with them.

:frightened:

Tony
User avatar
tony.latham
Gold Donating Member
 
Posts: 3265
Images: 17
Joined: Mon Jul 08, 2013 4:03 pm
Location: Middle of Idaho on the edge of nowhere
Top

Re: Fiberglass and resin really stick to foam??

Postby jimbo69ny » Wed Feb 06, 2019 1:29 pm

You're right. I just checked with my guy at Tap Plastics. He said I need to get a clear coat or paint the camper when its done.
jimbo69ny
Teardrop Master
 
Posts: 111
Images: 10
Joined: Thu Aug 09, 2018 2:53 am
Top

PreviousNext

Return to Foamies

Who is online

Users browsing this forum: No registered users and 3 guests