Peel ply

[wirejock]

Interesting thread. I never heard of weaving lubricant but it makes sense. Guess I need to buy more Peel Ply.
To answer my own question, no. Peel ply is not reusable. Ibtried it on a sample. It saturates like the first use but leaves most of the epoxy behind when removed. At least, that's what it looked like.

[Jvon811]

Originally Posted by DanH

Two cautions...

Removal with light force can indicate it really is just peeling, not fracturing the epoxy.

A key issue in loss of bond strength is contamination of the bonded surfaces at some point in the process. Plenty of research papers on the subject. With a woven peel ply, one source of contamination is surface treatment and weaving lubricant. The WalMart fabric may be fine; I don't know anything about it. That said, using either aircraft polyester or standard composite industry products is a safe bet.

Good to know, thank you! I never thought about it leaving contaminants for bonding the next layer.

The only work I've done with the Walmart Polyester is repairing cracks in my old RV-4 pre-honeycomb cowl. I usually just layer up 2-3 layers of Carbon Fiber (staggered edges between layers) and the Walmart "peel ply" works just fine for that. Never had any reason to try and bond a lot more structure to it after. If I do add layers, it's after I've already sanded on the section or part and I've never had any bonding or delamination issues (that I know of) because of the Walmart Polyester. I'm usually just using it to try and squeeze out excess resin.