PL adhesive and Poly resin questions

[109jb]

Well I got back from vacation with the family and it is now time to get back to work on the boat. I'm getting ready to install the stringers which brings up my first question. I am going to use PL adhesive to install the stringers. How long do you guys wait before you start tabbing them in with the glass and resin?

Second question. I'm not real familiar with poly resin use but have done plenty of epoxy layups. I bought poly laminating resin and also bought the wax for it. I will be putting 2 layers of CSM on the stringers before I put them in the boat. I figure since there will be additional layups to tab the stringers in later that I should not use the wax. There will wind up being areas where the exposed surface will be a layup that didn't have wax added. Do I need to worry about it or not? If so, what do I do? Can I just brush a layer of resin on that has wax added over those areas?

Last question. As I said, I have done plenty of epoxy layups and I have a bunch of peel ply and I'm wondering if peel ply works on poly layups like it does on epoxy layups?

Thanks in advance.

 

[wca_tim]

Re: PL adhesive and Poly resin questions

I would think twice about the pl adhesivce layup. I have recently had an opportunity to take a look at some i used last year and it swells a bit over time with the co2 buildup from curing and does not seem nearly as rock solid as what I've done with epoxy peanut butter...

It worked, but I won't use it again.

 

[chrishayes]

Re: PL adhesive and Poly resin questions

Interesting, I wonder if others have had similar experiences...? I used it to laminate two sections of ply together to form a longer length and it worked flawlessly. I would say there is no doubt that epoxy PB is a stronger, better, faster thing to use, but come on, to bed stringers takes a LOT of PB. THat is $$$!!!!!!!! I think enough people have had positive experiences with PL that I am likely to go ahead with using it as bedding for my project. Unless others chime in and say that they have had similar negative experiences...

 

[jonesg]

Re: PL adhesive and Poly resin questions

Its not supposed to set rock hard like resin putty, thats the appeal.

I used some PL 4200 to bed my splashwell backwall today, layed mat/poly over it 40 minutes later. solid.

I use unwaxed resin almost exclusively, no need for wax unless you do cosmetic finish work and need to sand with fine grit for paint.

I layed up stringers w/1 layer of mat/poly resin , bedded them in PL Premium 5200 , ran a seam of cabosil thickened putty down the hull joint and 2 layers of mat to seam the stringer to the hull.
Wiped it all down with acetone then painted with bilge paint.
Came out clean as a whistle.

 

[keepNitreel]

Re: PL adhesive and Poly resin questions

Using PL to bed the stringers is all you need. After you glass over your stringers you will never see the PL again anyway. If you do you might want to question your glassing capabilities

Use the PL and save your money to put somewhere else.

 

[ondarvr]

Re: PL adhesive and Poly resin questions

The only thing the PL does is space the stringer off the hull slightly, even if it went away after the stringer was glassed in place it wood make no difference.

 

[chrishayes]

Re: PL adhesive and Poly resin questions

Its not supposed to set rock hard like resin putty, thats the appeal.

I used some PL 4200 to bed my splashwell backwall today, layed mat/poly over it 40 minutes later. solid.

I use unwaxed resin almost exclusively, no need for wax unless you do cosmetic finish work and need to sand with fine grit for paint.

I layed up stringers w/1 layer of mat/poly resin , bedded them in PL Premium 5200 , ran a seam of cabosil thickened putty down the hull joint and 2 layers of mat to seam the stringer to the hull.
Wiped it all down with acetone then painted with bilge paint.
Came out clean as a whistle.

Jones, you say that you did a layup right over the PL before full cure? I just literally and hour ago used PL to fill the gap all the way around my transom install. The transom has been in place and cured for over a week. I was planning to wait at least 24 hours before I laid my tape tabs and final layup on the inside of the transom. Do I not need to wait? I would love to layup right over the PL joint now as it would all be cured by tomorrow sothat I can start my stringers in the morning. ANyone got a thought on this? WOuld be a BIG help.

 

[jonesg]

Re: PL adhesive and Poly resin questions

I spent time cutting mat, mixing up my polyester putty etc.

I learned from playing with it the PL must be skinned over at a minimum or polyester will get into it and cause it to go creamy...and start running. If that happens I suspect the polyester will not cure properly.

At a guess I'd say I went over the PL within the hr with no reaction.
Weather was hot and dry.

I find the 4200 sets a LOT quicker but doesn't set as firm.
I ran a bead 18 inches long, went back over it with a spoon and it was already too late, it was skinned in less than a minute.
Installing my splashwell backwall to the transom I used 4200 as a gap filler and went over it with poly resin and mat within 15 minutes with no ill effect, not that you could tell, its deep inside the layup now.
I bought the 4200 because they ran out of the 5200, seems to be ok stuff.