Glassing bottom of an UJ's Pirogue

[skeetwing]

I am ready to glass the bottom of my 13' UJ. Do I need to paint a coat of epoxy on the bottom before I lay out the glass? My concerns are 1. Can I move the glass around on the wet epoxy to get it in proper position. 2. The West system #206 "slow" hardener ain't so slow and I'm afraid it will kick off before I can get the 2nd coat on the glass. Can I just lay the glass on the bare wood and get it properly wetted out without first paintimg on a coat of epoxy?
On another subject will a keel stiffen the bottom significantly? Thanks for any advice you can provide.

 

[oldsparkey]

You can do the bottom both ways you asked about.

I like to epoxy saturate the wood and let it cure before glassing , Here is why.

The epoxy saturates the wood (soaks into it ) which helps to strengthen the wood plus it puts that coat of epoxy there to help protect it from water damage in case something penetrates the layer of fiberglass. It also gives the epoxy you will use with the fiberglass something to chemically bond to. You do have to wait for 24 hours before doing the glass work.
If you decide to do it that way it will require a little extra work.

The epoxy soaks into the wood and the outer fibers will rise up as the epoxy cures , this causes what I like to call , whiskers. The whiskers need to be shaven before the glass is applied and you do that with a light sanding , really light sanding. You need to remove the whiskers because if you don't and you lay the glass on the boat the whiskers will grab it and cause runs ( gaps ) in it.
If you run your hand over the wood you will be able to tell if all the whiskers are gone , a towel can be substituted for your hand.

Then lay down the glass and epoxy it to the bottom.

The epoxy saturation and then the fiberglass with the epoxy might strengthen the bottom so a runner would not be needed. If one is needed then consider it a sacrificial item since it will wear down over time and need to be replaced.

Chuck.

 

[stickbow]

I've done what Chuck said. I've put on glass with really thin epoxy and no 'pre-coat'. The latter was not a good idea in the long run. Got good glass to wood seal, plenty in the wood itself, but didn't fill the weave.

More often, I put a thinned coat of epoxy on, then lay the dry glass, then heavy/wet epoxy on with a squeegie. The thinned coat is usually starting to go off as I finish the epoxy. i like thin glass though, so wetting it out isn't all that hard. What weight glass cloth are you using?

Edited - A keel strip should stiffen the bottom fore to aft. I'm putting two thin ones on the outside of the glass, mainly as wear strips, on the pirogue I'm working on right now.

 

[Kayak Jack]

Your first coat of epoxy that wets out the glass should not fill the weave. It takes a few more coats to do that. No real need to do it in the inside. But, makes the outside smoother, and provides less drag in the water.

 

[skeetwing]

Thanks for all of the help, I think I will take Chuck's advice and let the first coat cure. Either that or I will need to get a much slower hardner in order to lay the glass before the first coat kicks off. I will send in a photo when I get done.

 

[stickbow]

Your first coat of epoxy that wets out the glass should not fill the weave. It takes a few more coats to do that. No real need to do it in the inside. But, makes the outside smoother, and provides less drag in the water.

That depends on the weight fabric you're using, and how light you're trying to make the item (whether boat or not). With very light fabric - 1 oz or less, you can wet it out and fill the weave with the first coat, and it comes out a lot lighter.

Either way, you'll be happier if you do a coat first, whether you let it dry or not, if you aren't making an ultra light boat/aircraft/hat for your halloween costume.

 

[skeetwing]

Thanks for all the insight. Stickbow I'm using 6 oz. cloth as I will be using my boat stritly for Duck Hunting and need a durable bottom. I may need two coats of epoxy to fill the weave but I don't care if I fill the weave or not unless it's necessary for strength. I will paint the boat camo and an unfilled weave might help flatten the finished look. As for Haloween I am going ultra light, just some tights and a Tutu.

 

[beekeeper]

I may need two coats of epoxy to fill the weave but I don't care if I fill the weave or not unless it's necessary for strength. I will paint the boat camo and an unfilled weave might help flatten the finished look.

If the weave is not filled, I would think you would have a very rough finish causing lots of drag. I would want the boat as smooth as possable, at least the wetted area.
Completly filled glass may not be stronger, but I would think it would add more skuff and wear protection.

beekeeper

 

[tx river rat]

I use to own part of a boat company, they gave us written material and instructions for layng up the boats. You do not get full strength until you have the weave filled and one coat over that.
Ron

 

[skeetwing]

Thanks Ron, I will fill the weave.