Fiberglass newbie with some questions

[toddallman]

To those that have used fiberglass cloth and resin on their teardrops...How much, would you estimate, Epoxy resin would it take to glass a 4x8 teardrop. The cloth is easy to figure but I'm not sure how far the resin can go. Would I need 1 gallon? My plan is to use fiberglass cloth on the sides and top and them paint. Do you think that is overkill? could I just epoxy the wood sides and then put the fiberglass and resin on the top? One last random question. What kind and or brand of resin did you use. I have seen it on ebay pretty cheap for boats. Thanks. Great web site.

[NathanL]

West Epoxy has a formula to figure it out and I have used it on boats and found it to be accurate enough to order materials. Add extra if you are new to epoxy.

http://www.westsystem.com/ss/estimating-epoxy-amounts/

[doug hodder]

For what's it worth....I've done 4 woodie trailers, only 2 had an aluminum top, 2 finished bright, 2 painted....never used any cloth on them, just the resin. I use cloth on boat hulls for abrasion resistance, but not on the top decks on them. I prefer West Systems, 1 Gallon with the appropriate pumps and catalysts will be fine. I use it for the construction adhesive on the major structure as well. Thing is....you gotta put on a lot of layers. 1 or 2 isn't going to cut it if you want a nice flat paint job on it.

PS....CPES won't build up for a nice paint job, well....it will with tons of coats, but epoxy is the best approach to build a surface in a short amount of time on a painted trailer. Others opinions will more than likely vary. Doug

[Forrest747]

Let the debate begin. I have used CPES dont waste your money West is very popular and good to work with I like Aeromarine epoxy system. its cheaper than West per gallon. Get the metering pumps. Good luck and somewhere there is a thread about applying fiberglass tape taht is great.

[nevadatear]

I used non blushing epoxy from Raka I was very happy with the results. A gallon is not too much. I did use fabric on the top and sides. Not sure I needed it. However , I didn't use it on the tongue box and it got a crack like something fell or sat on it first trip out. I then added cloth and no more problem. So I think I would still use glass cloth on the top and hatch for more strength on the curves, and to help hold the resin over the edge. But maybe not on the sides.

[toddallman]

Thanks everyone. I think I am going to epoxy the sides and use cloth on the top and the hatch. I have been stalking this sight for a while and I will soon have two full weeks off with the wife out of town. So that means building fun time.

[parnold]

On my first trailer (4x8) I put about 6 coats of polyester resin, no cloth anywhere, and used a gallon and a half of resin. On trailer number 2, 6.5 x 10, I am taping all seams, and the edges of the roof. I had one seam on trailer number one that got a hairline crack, so I am using the tape on number 2.

Polyester resin is way cheaper than epoxy resin. There is no need to spend the money on epoxy resin.

To extent pot life, you can refrigerate your resin. It cures pretty darn fast in warm weather. Using a foam roller for application, I wasn't able to apply a full quart before it started setting up on me, in 80 degree weather.

[NathanL]

I am not a fan of using polyester resin on bare wood or plywood. First of all it doesn't bond very well to wood, it does a great job of bonding to intself and cloth however. Polyester resin is not waterproof (use a moisture meter on it after it's cured and see how much it actually absorbs and you will be suprised), while it probably does an OK job working on something like a teardrop where it is not continuously exposed to water but why chance it. There is a cost difference but the labor is just the same and for me I would just go with epoxy if you are going to go thru all the trouble of encapsulating your wood with the cost difference between a gallon of epoxy and polyster resin being less than $75.

[parnold]

If he plans on having it natural, epoxy might be a good idea for peace of mind, but if it's coated like mine with paint, it doesn't matter which he uses. I have been using polyester resin on various woods for years with absolutely no adhesion problems, although I did experience a curing problem due to the crap underlayment and the chemicals in it. The amount of moisture that may enter through the resin is far less than the moisture you're exhaling in your sleep, unless he plans to turn it into a submarine, the porosity is a non issue.

Alot of people are on a budget, and if an alternative that can save $100.00 is available, it should be researched.

[bobhav]

Hi Folks,

Back in the late 1960's, I worked in a small fiberglass factory that built fiberglass horse trailers. The molds were made in the shop. We waxed the molds prior to every use, the wax was used as a parting film. Gelcoat with hardener was sprayed into the molds and allowed to harden. We hand layed all of the fiberglass matting. The resin was applied with natural fiber brushes with wooden handles.

One of the things that we did that seldom see mentioned is that we rolled the air bubbles out of the resin / matting with a small metal roller that had many grooves cut in it. The trapped air would be pressed out of the material and escape thru the grooves. This allowed us to use less resin and made for a tougher product. I see that these roller can be purchased for less that $20. I recommend using them.

In the course of building a horse tailer we 'glassed in a lot of plywood supports and there were never a perfect fit. We would cut many short strips of glass cloth ot matting and cut trough the centerline of the length, these cut were made in dry cloth about 75% thru the width from both edges, and and staggered on about 3 inch intervals. the cuts allowed for the cloth be "bent and lapped" around curves. If we needed more strength we added more layers. Btw, we roller the air bubbles out be fore we added another layer of cloth.

Hope helps and doesn't add confussion.

Bob H.