Fiberglass how to?

Andy Grant

Andy Grant

Well-known member
My epoxy and fiberglass should arrive this Wednesday for my sculling float. It is strip built. My plan is:

1. seal coat with epoxy

2. lay down glass over hull and roughly cut to size (a couple inches big)

3. wet out glass with epoxy with a chip brush and squeegee off excess.

4. add another layer of epoxy to smooth.

Is this the right process? I have never really glassed anything before.
 
My epoxy and fiberglass should arrive this Wednesday for my sculling float. It is strip built. My plan is:

1. seal coat with epoxy-make this part of the laminating process, not separate. Also, do NOT put any uncatalyzed epoxy on the wood like some folks might tell you for penetration..........do NOT do.

2. lay down glass over hull and roughly cut to size (a couple inches big) Do all your cutting ahead of time. Wet out hull.........several times if necessary and then lay down your glass.

3. wet out glass with epoxy with a chip brush and squeegee off excess. Heck, use a big 4" brush....that's what we use when laminating boats. Also use paint rollers for spreading and wetting. Makes life much easier.

4. add another layer of epoxy to smooth. yup

Is this the right process?it's a good start. :O I have never really glassed anything before.
 
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Andrew,
like Lou said, when you start, you want the epoxy to soak into both the wood and glass as one layer...it basically binds them to one another. It's really a LOT easier than you expect it will be. Enjoy!

Scott
 
You may have to use a faring compound before doing the glassing to fill all the cracks and nail heads. If you don't, you will have air pockets under the glass.
 
try those yellow bondo sqeegees, they can wet out, and press the resin right through the cloth, this will also save you from waisting the exspensive resin. if you want to get the smoothest sanding coat" top coat ,use a 4 inch brush ,try and use loooong stokes, cover the boat in one pass, going from tip of boat to rear , and use gloves and apply in a well ventilated area.
 
With the epoxy, I ordered some of the bondo type squeegees and a roller to help lay down the cloth. I will get a few 4" brushes to put the resin on with.

so I should:

1. fill all holes. I was planing on using the epoxy mixed with wood flour for them.

2. wet out hull

3. lay pre-cut glass onto wet hull

4. work glass into epoxy on hull

5. after set up put another coat of epoxy on to smooth hull
 
1/Fill all holes and cracks and sand smooth

2/cover floor around hull with visqueen
2.1/ wet hull with epoxy, keep wetting till there are no "dry" spots

3/lay glass on wet epoxy and pour epoxy on glass

4/ squegee epoxy through glass watching for air bubbles.

5/ let cure overnight

6/wash with water/detergent if there is blush

7 sand lightly with fine grit.

8/ tack cloth dust off ,use rag with thinner

9/ roll/brush anonther layer of epoxy

10/ repeat 6,7,8 and 9 till cloth is filled and boat is smooth.
 
Lee,

What is "blush" and what does washing with detergent do? What kind of detergent?
 
Epoxy blush is a waxy stuff that forms on the surface of some epoxies as it cures. It clogs sandpaper and prevents subsequent coats from sticking. Cheap dishsoap washes it off...and works better than Laquer thinner too. I never had it with the Epxy Plus I used from Clark Craft but I still washed it down before sanding and recoating.
 
I read on the RAKA data sheet that a solution of ammonia water would wash away the waxy blush. Luckily I never had a problem with it.

Also, if you can devote a full 10 hours straight to the top coats of epoxy, you do not have to wait for each coat to cure overnight, wash, sand, repeat. You can let the epoxy coat cure to tacky (not sticky) and repeat with another coat of epoxy. Wait and repeat as needed. The time needed for a cure to tacky is determined by the fastness of the hardner used and the ambeient air temp. I was using fast cure on an 80F deg day, and I was able to recoat about every 2.5 hrs. I managed 3 coats in an afternoon/evening. No sanding!! If you recoat too soon the undercoat will sag a bit. If it cures beyond tacky then you will have to wait for a full hard cure and do the sanding bit.

BTW, it sounds more scary than it really is...

Best,
Brian F.
 
Instead of using the wood flour for fairing, try the microballoons. They sand a lot faster and can fair to a razors edge.

Good luck!
 
I wish I would have included the microballons in my order. What about Phenolic Microballoons? They are listed as easy sanding but add strength and flexibility for larger gaps. I don't know the specifics on large versus small gaps, but some could be large.
 
Personally, I would use only fumed silica (cabosil) for bridging gaps large and small. The microballoons just don't give me a sense of security for structural integrity. You can always use a mixture of the two to make it more manageable. I do this on my decoys, a 50/50 mix of cabosil and microballoons. The halves don't come apart and it sands smooth for a almost invisible joint. Just a thought.....
 
I do have some silica from West Systems that came with a repair kit that I could use. I wouldn't have to wait on shipping then.

I should receive the epoxy and glass today. I hoped to start on the project this weekend. I have to work Saturday morning and my wife wants to go fishing Sunday. I definitely can't turn down my wife on fishing!
 
Personally, I would use only fumed silica (cabosil) for bridging gaps large and small. The microballoons just don't give me a sense of security for structural integrity. You can always use a mixture of the two to make it more manageable. I do this on my decoys, a 50/50 mix of cabosil and microballoons. The halves don't come apart and it sands smooth for a almost invisible joint. Just a thought.....
Click to expand...

I would echo, echo, echo (couldn't resist) Terry's suggestion on Cabosil. That's what we use all the time.
Mix it with the catalyzed resin.....voila......."Gorilla Snot".
Lou
 
Well, you'll find that the fumed silica is a lot more expensive than the wood flour, but then I don't build boats. Besides the odd project here and there, I mostly use it for my decoys. Call around to any fiberglass supplier (wholesale/industrial) and see if they have a generic product, then you won't have to wait for shipping.

Good luck and keep us posted!
 
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