Stringer replacement scew up?

[slo boat]

Hello everyone. I recently got my first boat, a 74 Eliminator 19' with a S/B Chevy and Berkeley jet.<br />First thing I did was go through the engine. When it was ready to go back in I noticed the stringers were rotted and decided to replace them. I cut them out, sanded down to a fresh layer of resin, cut the new stringers, and laid them in place. I used fiberglass reinforced filler on the bottom of the stringers to take up the small gaps between the hull. I then laid some glass rope and laminating resin along the edges to make a smooth radius for the glass mat. I started laying the mat, then ran out of resin. I went to buy some more to finish up. Now that I got one layer of 2 oz mat down, I want to add another layer of woven roven where the engine sits. <br /><br />My problem is that I bought and used sanding resin for the majority of the job when I ran out of the laminating stuff. From reading up on resin types it seems that another coat will not bond to this resin once its dried, because of the wax additive. <br />So what is the verdict? <br />1st, does the sanding resin bond well to the wood and the hull?<br />2nd, can I lay more resin on top and not worry about it?<br />3rd, do I have to sand it down and clean it with acetone before the next coat?<br />Or do I have to rip it all out and start over ?<br />I'm almost out of resin again, and need to buy some more, should I use laminating or sanding?<br />Im afraid that if the sanding resin didnt bond well to the hull the engine torque willl rip the stringers right off the floor! <br /><br />your input is appreciated greatly!

 

[BillP]

Re: Stringer replacement scew up?

Don't fret...it isn't a big deal and just means more labor with surface prep. Sand and do a flood/wipedown with styrene. It will bond like new. Don't substitute acetone for styrene. Acetone is a cleaner while styrene chemically links and bonds poly to poly. Styrene is the correct thinner for poly. Poly resin is made with styrene.<br /><br />Use laminating resin for everything. The tacky (waxless) surface will go away in a month or so if you do nothing. Otherwise, coat the last layer of glass with finishing resin (has wax).

 

[jfholijr]

Re: Stringer replacement scew up?

What is the purpose of the wax or finishing resin? Is it just for sanding purposes? I'm redoing the stringers, floor and transom in my boat and I like the Idea of using the laminating resin for everything. I'm just wandering if there is a real need for the wax especially under the floor and on the stringers. Of course I know I'll have to cover the new fiberglass with gelcote where there will be sunlight exposure.

 

[BillP]

Re: Stringer replacement scew up?

Whoohoo,<br />In boatwork, polyester finishing resin is only for sanding or having a tack free final surface. Everything can be glassed using laminating resin (it makes the job easier because you can come back next week and do more glasswork without sanding first). Then add a final topcoat (no glass) of finishing resin only where you want the surface to be tackless...places like the top of floor where you walk on. If painting or gelcoating over the floor you can do it over the tacky laminating resin and no need for any finishing resin. You can also buy a liquid wax additive for laminating resin instead of buying finishing resin. Where I live it is called "Modifer C". Good luck.

 

[jfholijr]

Re: Stringer replacement scew up?

That's what I thought. Thanks Bill.

 

[slo boat]

Re: Stringer replacement scew up?

Thanks a bunch for the info, Bill. <br /><br />Now I'm finished with the stringers. Time to do the floors,but i have a question about sealing the wood. Will resin alone work well as a sealer, or should I opt for some kind of wood treatment. There will be carpet on top of it, just want to keep the moisture away.<br /><br />Thanks again

 

[BillP]

Re: Stringer replacement scew up?

I guess you are using plywood right? It needs to be sealed on the underside and topside. I've used polyester resin without glass to seal ply and it worked several years but it can't be depended on for sure. If using polyester resin the best way is to glass both sides with a thin cloth (6oz-10oz) or surfacing mat (3/4oz). Mat is easier. Use heavier glass if you want more ding resistance.

 

[jfholijr]

Re: Stringer replacement scew up?

What I'm doing with my floor is I'm putting one layer of 1.5 oz mat on the underside and 2 layers on top. I figure that should be better than they way it was.