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Moderated Best way of finishing epoxy fiberglass? Workflow?

 

I have been building my first boat just small 3,5m sailboat as first practice build before taking on most likely eco 6.?

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What is your best way of working with epoxy and fiberglass to get as close to as possible to shop finish? I personally have not tried peelply is it worth it? Also is there some other alternatives?

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My current optimal workflow lookslike?

1. Basecoat dry rolling epoxy with foamroller

2. super quick rough sanding

3. applying glass fabric and covering with foamroller

4. Quick sand 240 grit applying additional coats up to 3 to get good sanding finish?

5. Painting over with marine grade paint 2-3 coats

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Few questions:

Would peel ply make process faster/allow adding more epoxy on single go so no need for multiple layers?

How ready is peelply finish still needs sanding ?

Any alternative ways of doing close to factory finish that i could skip some steps or make some process in otherways?

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Lessons so far:

On next build looking to base coat all ply pre cutting, did not do it with this build but would greatly speed up the process.

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I have never used peel-ply and have only built one boat, but I did learn a bunch during the build. When I payed my fiberglass I used a squeegee to spread it. This helps to ensure you don¡¯t have excess epoxy in the layup. You can also use a fin roller to push out any air and excess epoxy. You don¡¯t want the glass to float in the epoxy or puddles of epoxy sitting on top. After it¡¯s cured I used fairing compound and spread on as thin as possible with a 8¡± or larger drywall taping knife. Sand and repeat as many times as you want to get the surface as smooth as you want. Once you put your first coat of primer on, you will see more imperfections. A couple more rounds of fairing compound in those areas and sanding then another coat of primer. The quality of finish depends on how much time you want to spend fairing and sanding. I went for a 20 foot finish on my boat because I wanted to be on the water instead of in the garage sanding. I used ¡°Total Fair¡± fairing compound. I thought it was great stuff, but you can make your own too. That¡¯s my non -professional opinion anyway.

- Mark
 

In reply to the question about finishing with fiberglass and resin, this my method.?
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Drape, or spread the fiberglass cloth over the dry substrate, and if necessary for large surfaces tape into place so it does not slide or get blown off.
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Apply first coat of resin with roller. This is best done in warm air conditions so the resin flows better and achieves a good wet out. If applying in cold weather conditions it is good to warm the resin a little before applying. Of course warmed resin will go off quicker so only mix up small batches.
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Before the first coat of resin fully cures, that is while it is still tacky, apply the second coat of resin to better fill the weave on the cloth.
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I then follow up with a third coat of resin into which I mix light weight filling powder to create a slurry, and once again I try to apply it before the second coat has fully cured. This third coat provides the base for sanding and fairing, but you may still need to trowel on some filler to fill up low spots. How much filler, and how much sanding depends entirely on the finish you want to achieve. I always go by the one meter rule, that is so the surface looks ok from a meter distance.
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I have only used peel ply on small components, but it certainly makes a difference and provides an essentially paint ready surface. If I was ever silly enough to build another boat I would investigate the cost of using peel ply over the entire surface. If it was possible to purchase peel ply in bulk for a reasonable cost it could certainly save a lot of work.
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David
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Hi David we work more or less the same and as I always say it depends on the result you want to obtain, more finishing and more epoxy filler :-))
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The peel ply is a very refined job but it also has a considerable cost...
I work on the dry laminate panel with epoxy filler made by me, I decide what paste to create for the various layers of filler.
And I would also add that everything depends on the alignment of the hull assembly, otherwise you'll go crazy grouting....

bye
 

Hi Peets
The others have made good replies. Here is mine:
For not using peel ply
1. Before assembly, pre-coat your ply pieces using a squeegee. You use less epoxy than using a roller. I like to use a "Bondo" spreader. Then a quick sand to knock down the rough wood fibers.?
2. Glue your pieces together. If the pieces are not fair, shape the wood pieces to be fair.
3. Glassing big jobs or level jobs - place the dry glass cloth, then wet out. For small vertical jobs - wet out on the bench, then apply wet cloth to the wood.
4. Without waiting (while the glass is still sticky), fill the weave with epoxy thickened with a mixture of glass bubbles/microballoons and colliodal silica. Make it creamy. It should fill the weave without using very much epoxy. Bumps will sand down very quickly. It will be easy to sand. If you did a good job, you will only have to do it once.
5. Sanded microballoons must be either clear coated with unthickened epoxy (with a squeegee) and then fine sanded or use an epoxy sealing primer to seal it.?
6. Paint
Peel ply works great in the right way and you just have to finish sand. But sometimes it is better to fill the weave with the creamy mixture.
Cheers
Patrick

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