CSM Veil

Hello All,
I'm getting ready to epoxy plain carbon on the inside of my transom (x2 layers). 1st layer/ Warp bundle across 2nd layer/ Warp parrallel to the Keel overlapping 4-5 inches in the middle of the transom.
I don't have any crackes in the splashwell yet and want to stiffen this area up so I never will.

It has been suggested to me to use a veil to help the bond line at the old glass The way I understand csm is it's necessary for PER to help bond but with epoxies better adhesion the csm becomes the weak link.

If a test panel is made of epoxy, point of failure will be at whatever layer the csm is located every time. I'm going to talk in circles for a second as I've also gathered the veil is roughly 80% resins and because it's only 10 mils it helps more than hurts in the bond line

Do I need the veil or will some filler serve the same purpose?

The reason I suggest maybe a filler is a veteran of glassing told me his test decades ago. He had screwed a project up and while pulling the glass from the wood he noticed it came off fairly easy. He next mixed a little asbestos powder(It wasn't a bad word then) into his resin. Let it cure in the same manner as before and pulled it apart. This time chunks of wood came off with the cured resin. Obviously the filler added teeth to the resins.

Do I need more surface area on each side of the transom?

Any input along these lines is appreciated!
Thanks in advance
Bull

 

Mat helps with the bond when using polyester due to polyester’s very poor secondary bonding ability (relative to epoxy). With epoxy you generally do not need it, in fact it will be the week link.

Joel Shine

 

Thanks, I was thinking of adding some graphite filler to my precoat to help the bond to the old(1991) glass? Is this logical?

Here's a pic of the boat. They did a great job on the gel but the floor was soft and I uncovered a mess. I believe PER has it's place but not with wood below the waterline.

 

glas to glass with epoxy, only use fillers if you must. I would use milled fibers

 

I'm not dead set on filler glass to glass is fine.

Thanks JR