I have to do a little fiberglass work today.

1. How long after you add the hardener to the resin do you have to work before is starts to harden?

2. How long after the job is done can you use the boat? This is an interior, mainly cosmetic job. I've seen major hull repairs done to race boats and they race them the nect day. So, I guess I should be good by the weekend.

3. Is a resperator necessary? I was doing a little testing last night and that resin is pretty potent smelling.

4. I am using two layers of fiberglass mat per the manufacturers instructions. Should I put down the first layer and then the second or just sandwich them together and put it down as one?

The more hardener you use the faster it will setup, you dont have to use what they say to the tee. The faster the setup it will be harder to get the air bubbles out and might not be as strong. I would do one layer at a time and use a resperator if your inside. You will have about ten minutes to work with it then you will just be messing it up. 3-4 hours should be good before you get it wet.

Im not an expert by any means. If its really only cosmetic then anything will do but if it needs to be strong, I would use epoxy like West System which you can get at any West Marine or BoatUS. It has the greatest adhesion on existing work. It also cures much slower which gives you some work time. If its vertical or overhead work, make sure you get microfibers or something to thicken it up.

Thanks Guys,

I am installing a foot rest insert into my dash. The glass work is going to be behind the dash were it will not be seen. It shouldn't be that hard of a job, I am just a fiberglass rookie.


Dave M.

West Sysytem offers two different hardeners. Slow and Fast. Like Too Old said, check the label on the hardener for pot life. In fact, get one of their publications that gives specific answers on all of the questions you have.

Don't forget that if you are using Epoxy that it cures by volume. So if you have a lot in the cup it will harden MUCH fast then if you have it spread out all over the table.

Polyester you should figure about 20CC's of so will give you about 15-20 min of work time. Then you are done. Polyester cures more to the temperature outside. HOWEVER the cureing process creates heat and can start to cause it to kick a little faster. Just adjust a little for the outside temps and you should be fine. You do not want it to kick to fast or it will be brittal.

Jon

Thanks Guys,

I got the job done yesterday. It's not the prettiest work but is in an area that will not be seen. I think I used too much hardener on my first batch. I started with a pint of resin and ended up throwing out about 1/4 of it because it hardened up sooner than I thought. Hopefully I get some rough water on Saturday to stress test my work.