PL premium or Polyresin with cabosil

[inovativethkr]

I am going to set my motor mount stringers for a small 2.5 liter engine.
Can someone tell me what would be the best bedding material to use either
PL premium adhesive or polyresin with cabosil added to bond these to the
hull? Of course I'll be covering these with fiberglass.

 

[boatflipper]

Re: PL premium or Polyresin with cabosil

Personally I would use either of them. Each has their own advantage and disadvantage.
With PL it is already made and all you have to do is squirt it out. And it is realively cheap.
With resin and cabosil and whatever else you decide to use, you have to mix them all well and then pour it which could be quite messy.
Others will chime in with much more intelligent responses
Good luck!

 

[redfury]

Re: PL premium or Polyresin with cabosil

Combo of both. Use the PL to set your work, and then use the poly/cabosil mixture to radius the corners for your glasswork. You get the ease of a ready made adhesive for set up, and then the additional strength of the "fillet" for the glasswork...

Trust me, PL does not work for creating fillets, it just bulges as it cures. Use PL premium though, as it is extremely aggressive in its bonding...you can glue wood with frost on it with the stuff.

 

[BobsGlasstream]

Re: PL premium or Polyresin with cabosil

redfury Re: PL premium or Polyresin with cabosil

--------------------------------------------------------------------------------
Combo of both. Use the PL to set your work, and then use the poly/cabosil mixture to radius the corners for your glasswork. You get the ease of a ready made adhesive for set up, and then the additional strength of the "fillet" for the glasswork...

Trust me, PL does not work for creating fillets, it just bulges as it cures. Use PL premium though, as it is extremely aggressive in its bonding...you can glue wood with frost on it with the stuff.

I couldn't have said it any better, and it's exactly what I did. One addition is to make sure you radius the tops of the stringers and the glass will lay over them much better.
Good Luck
Bob

 

[osborn159]

Re: PL premium or Polyresin with cabosil

i used pl premium to ahere my transom and stringer to the hull, wow that stuff sticks like stink!!! radiused what ozzed out w/ a plastic spoon so it didnt get away from me, came back and filleted w/ pb mix, nice and radiused ready for encasing and final f/g layup.

 

[erikgreen]

Re: PL premium or Polyresin with cabosil

If these are actually the stringers that the motor sits on, I'd use poly resin and something other than cabosil, like milled fibers, to glue them down. That's an area of construction where you want maximum strength, and the hull really doesn't flex there at all unless you have a strange hull.

"Bedding" is only really needed to prevent hard spots, which are places where the fiberglass hull flexes and the underlying structure doesn't. No flex equals no chance of hard spots, so just glue the stringer/mount down hard and then create fillets and glass.

PL is easy and cheap, but adds effectively no strength (not because it's not strong stuff, but because it's never loaded unless the fiberglass fails) and I'd think you'd want to go with strong over easy here.

Erik

 

[lowkee]

Re: PL premium or Polyresin with cabosil

Combo of both. Use the PL to set your work, and then use the poly/cabosil mixture to radius the corners for your glasswork. You get the ease of a ready made adhesive for set up, and then the additional strength of the "fillet" for the glasswork...

Trust me, PL does not work for creating fillets, it just bulges as it cures. Use PL premium though, as it is extremely aggressive in its bonding...you can glue wood with frost on it with the stuff.

Couldn't agree more. Exactly as stated.

 

[inovativethkr]

Re: PL premium or Polyresin with cabosil

I have another question in reference to fiberglassing the motor mount stringers. Can anyone tell me how many layers of 1708 biaxial mat I will
need to put on to get a 1/4" thickness since that looks like how thick
the original manufacturer had made it.

 

[redfury]

Re: PL premium or Polyresin with cabosil

based off the thickness of the 1708 that I peeled off my hull in an area that delamed on me, I'd say you'll need a minimum of 4 layers to get 1/4 inch thickness.