epoxy resin and fiberglass resin,transom repair

[Shifflett115]

whats up guys, im currently redoing the transom on my 1985 bayliner 19ft cuddy,its an outboard boat.it only has one layer of 3/4in ply on the transom ,im going to use epoxy resin to attach the new wood to the outside skin and to the wood at the bottom that is still good, bsaically im just replacing the main section of the transom,not the bottom ,then im going to use two layers of 24oz woven roving and fiberglass resin to make a new inner glass wall,will i have a problem with the fiberglass resin bonding to the epoxy resin or will it all just bond together, im also going to add two gussits out of 2by 10's from the transom to the stringers at a 45 degree angle,do you guys think everything will work out,your advise is greatly appriciated,thanks guys

 

[rockyrude]

Re: epoxy resin and fiberglass resin,transom repair

If you have the room I'd try to put two layers of ply back. One layer is borderline at best for the max horsepower for that boat. Woven roven will work, just alternate with chopped mat. If you need a smooth inside surface, finish with a layer of mat. If you are starting with epoxy why not finish with it?

 

[ondarvr]

Re: epoxy resin and fiberglass resin,transom repair

From what you said, you're just using epoxy to glue the plywood in place. So long as you're not trying to bond polyester to epoxy your OK, that means no epoxy can be left on any surface you plan to use polester resin over. Mat does need to be used between each roving.

 

[Capt. Mike]

Re: epoxy resin and fiberglass resin,transom repair

polester resin will not stick to west epoxy unless you sand it first

 

[Bondo]

Re: epoxy resin and fiberglass resin,transom repair

im going to use epoxy resin to attach the new wood to the outside skin

Ayuh,....... That statement needs somemore clarification......

Is that the Outside of the Hull,..??..??

 

[andy6374]

Re: epoxy resin and fiberglass resin,transom repair

Agree with everything that has been said.

But I would do more than 2 layers of roven woven. You are already laying up glass...lay some more. I would do at least 3 layers of roven woven.

 

[sbklf]

Re: epoxy resin and fiberglass resin,transom repair

I am finishing a repair that I used Epoxy and Poly on. Lesson learned, I will never do that again. If you can not go all epoxy or if you do not have a good seperating point where the epoxy can stop and poly start and not have to try to get the poly to bond to the epoxy, I would go all poly.

 

[Shifflett115]

Re: epoxy resin and fiberglass resin,transom repair

thank you guys for all your info,im going to use epoxy resin on all of it instead of fiberglass resin im going to lay two layers of 3/4 ply but i cannot bring the second layer all the way to the top of the transom because the well is in the way and i dont want to take the top off the boat,but with the two gussits and everything glassed together it will be stronger then factory.im going to use the west system epoxy resin,i heard that stuff is really great and easy to work with.

 

[Shifflett115]

Re: epoxy resin and fiberglass resin,transom repair

should i drill some holes in the new ply so when i install it to the inside of the outside skin some resin will oose out ,would it make it stronger

 

[OhWellcraft]

Re: epoxy resin and fiberglass resin,transom repair

If you are using epoxy you probably don't need to drill holes in the ply, but you do need to thin down some resin and coat ALL surfaces of the ply to waterproof it before you glass all in. As far as attachment to the outside skin use thickened epoxy to glue them togather. Mix up a batch of the thickened(about like peanutbutter) trowell onto ply clamp togather very well. You can use the existing outboard holes with large washers to clamp with and you may also have to drill a few more just to make sure it is clamped very well. Many use 2x4's instead of washers to get a true clamping effect. Once that has all cured fully then you can start glassing the inside skin, just make sure to take your time and make sure everything is cleaned with acetone. Prep work and pre planning are crucial at this point of the job. Good luck and keep asking questions if you have any, people here are very helpful in all matters.

 

[Shifflett115]

Re: epoxy resin and fiberglass resin,transom repair

what can i thin epoxy resin with?

 

[Coors]

Re: epoxy resin and fiberglass resin,transom repair

It depends on the brand, google their website; some use denatured alcohol.

 

[Old Salt Oz]

Re: epoxy resin and fiberglass resin,transom repair

what can i thin epoxy resin with?

You can us standard Methylated spirits, adding up 40% by volume after mixing the resin and hardener.

The above is great for treating the ply before you install it, being thinner the penetrate deeper and improve the protection. End grain will suck up a lot of resin so be prepared to add a few extra coats around the edges.

When joining the two ply sheets with glass between them I would be drilling 6 mm holes on a grid of 60 mm. To make them stick well and thicken the resin use Micro Fibres, this makes one of the strongest epoxy glues, mix to about toothpaste consistency, spread and clamp.

Take care not to clamp too tight, squeezing all the glue out and leaving a thin layer will weaken the joint.

You can use the same mix to form a solid gusset on the inside of the transom, slap it into the corner and shape it will a small jar or other round container, just make sure the finish is without lumps and bumps because sanding this stuff off after curing is hard going.

The rounded gusset will make the joint strong as well making the layup easier to do. Another bonus is it will easier to clean later.

I Hope this helps.

Avagoodweekend......