MadManAndrew

Would an experienced boat builder please explain how to fiberglass balsa boat hulls? I made an attempt at it today using techniques and reccomendations I found on a how-to site, but it turned out far from acceptable. I'd also appreciate some tips on removing hardened glass resin from balsa...Just fine-grit sandpaper? Thanks in advance.

Dreamin Hemi

firststatecomposites.com/howitsdone_.html

The link above will give you the basics. Even though it shows how I build fiberglass hulls from my molds, the techniques are the same. Getting resin off balsa? Lots of sandpaper. How about some pictures of what you got yourself into...

A few questions for you....

1. What weight cloth are you using?
2. How are you manipulating the cloth?

MadManAndrew

I was trying to use 3/4 oz., as I'm basicly just trying to seal the wood, but it seems just way to fragile to even work with it...Even just sliding it around on the table to cut it started to stretch and unthread.

Dreamin Hemi

use a 1/4" nap 3" long paint roller or disposable brush and apply a coat of resin directly to your hull FIRST. Once covered with a thin coat of resin, drape the cloth you have over and roll or use your brush and work the glass in different directions as shown in my website page.

Dreamin Hemi

Another thing, to avoid snags while trimming the cloth, use sharp scissors.....it makes a huge difference. When cuttign your cloth from the roll or table, try using a straight edged ruler and a new razor knife ran along the edge. It holds the cloth nicely and the shap razor glides across without pulling the fibers around.

MadManAndrew

That's where the problems came in. I draped the cloth over the hull and began to try and pull and spread the wrinkles and creases out, but the resin made it so that it just folded over itself and created large folds I couldn't work out, and I ended up having to scrap the cloth.

MadManAndrew

That's where the problems came in. I draped the cloth over the hull and began to try and pull and spread the wrinkles and creases out, but the resin made it so that it just folded over itself and created large folds I couldn't work out, and I ended up having to scrap the cloth.

Dreamin Hemi

Sounds like you may be doing too large an area at once. Work on one section at a time. Overlap each section by 1/4 to half an inch. You will have pleanty of time to work the glass around. Heck, I glass an entire mold with two layers of different glass types before it kicks off. Take you time and plan ahead what you will need before you mix your resin.

MadManAndrew

Okay, thanks for the tips. I'll have another go at it tomorrow and report back with results!

Dreamin Hemi

Good luck. If you feel the need to give me a call, please do not hesitate. PM me if you would like my number. I'll be in the shop most the day but always have my cell with me.

MadManAndrew

Fiberglassed the bottom of the hull today! Using a few things I picked up from you, and a couple tips I got from talking to my dad about the big boats, it turned out pretty good.  Pics when I get the rest done.

Doc.316

A really cool tip for fiberglassing...Use the backing off of Monokote..(ya know the stuff the airplane guys use)....which can be obtained at a hobby shop (they sell it in monokote rolls at the shop I go to)......well wett the surface (boat/airplane)....lay glass down ..wet glass.....put monokote backing on ......get your credit card out (don't worry it wont cost ya unless you get epoxy on the card)...start at the middle and work all the air bubbles out ...and at the edges mop up the excess with a paper towel......tape down the edges...and let it set...

The next morning get up and peel off the monokote backing. You will have a surface with light sanding and priming that is ready for paint..

It works really well.

Steve