kinds or release fabric/peel ply

[Anatol]

Hi all,
I'm doing some large areas of hand layup (epoxy/glass over ply). I'm not experienced with peel ply but anything to get a smooth surface and avoid sanding is a plus. I will not be vac bagging. I found kitchen cling-wrap serves well on small areas. Does anyone have suggestions for best, and best value, disposable or reusable release fabric for, say, an area like an 8x4 ply sheet?
thanks!

 

[rwatson]

Cling wrap works ok, until you get a bit caught in a tight corner and then it tears. It also bunches up badly sometimes, and is hard to squeegee flat.

You might get some 'taffeta' from a fabric shop for cheap, but make sure you test a small batch, as some have blends of other fabrics and tend to stick to the surface badly.

The commercial brands have performed best, and I favour the ones with a coloured stripe to make it easier to see when removing it.

Best results happen when using smaller sections on compound surfaces, as long sections tend to bunch up - for example. I would use two pieces on an 8 x 4 sheet of plywood for ease of application. Any ridges left are easily sandable, and will reduce the 'crease lines' that are often obtained when trying to lay a large section.

 

[Anatol]

"You might get some 'taffeta' from a fabric shop for cheap, but make sure you test a small batch, as some have blends of other fabrics and tend to stick to the surface badly"

I've seen elsewhere people talking of using nylon shower curtain. Does nylon cloth release because its nylon or because of a characteristic of the weave? I suppose one wants a fabric which is not wettable by epoxy?
Could one spray a release material on a fabric?
What about the nylon polyamide superfine weave used for sikscreening? That's tough, but may be more expensive than peel ply

"I would use two pieces on an 8 x 4 sheet of plywood for ease of application."

Nice tip. thanks.

 

[robwilk37]

the local fabric store has everything 30% off the last weekend of every month. i stock up on ripstop nylon and poly dress liner usually from the shorts bin (ugly colors). right around $2/yard most times, works just as well as the purpose built stuff...

 

[Anatol]

i stock up on ripstop nylon and poly dress liner usually from the shorts bin (ugly colors).

love it!.
So ripstop is good?
What are the characteristics of a cloth that will work well?
do you have to clean it for a second use? Or do you toss it?
thx!

 

[robwilk37]

i like rip stop. straight nylon or poly can be a bit of a challenge if bought too light weight. opt for heavier at first til you get used to working with it. only buy un-coated materials and absolutely no blends or elastic weave. youll not be able to re-use it though, dont even try.

and for fun go out at night and pull a sheet off in the dark... pretty cool.

 

[Anatol]

Thanks for the added info.
"youll not be able to re-use it though, dont even try."
I'm not sure I'm comfortable with creating that much waste

 

[robwilk37]

yeah, im bummed about the waist too. i re-use as much as i can, but peel ply is a one off necessity. think of it this way... peel-ply used properly eliminates the need for blush wash and sanding between lams. so toss it in the recycle bin when youre done and hope it gets recycled...

 

[ondarvr]

The amount of waste in infusion is one reason some fabricators are reluctant to adopt the method, it can fill a dumpster quickly.

 

[rwatson]

If you think old, cheap scrap fabric is waste, think about the abrasives, excess epoxy, personal effort, etc it has saved

 

[SaltOntheBrain]

I only tested a small piece, but Tyvek leaves a nice, uniform texture and rips off easily.

 

[Anatol]

I only tested a small piece, but Tyvek leaves a nice, uniform texture and rips off easily.

nice idea. make me wonder about polytarp too...
what about construction grade polythene?

 

[Anatol]

If you think old, cheap scrap fabric is waste, think about the abrasives, excess epoxy, personal effort, etc it has saved

fair point.

 

[ondarvr]

If you think old, cheap scrap fabric is waste, think about the abrasives, excess epoxy, personal effort, etc it has saved

Every part made has a totally different amount of waste associated with it. Some have little to no sanding, it's almost a de-mold and ship process, this is where infusion waste comes into play.