Never sand fibreglass again!

[Ed Snyder]

Use 'peel ply' 

This is like nylon fabric, thin slippery and has a coating so it can be peeled off the glass you are laminating.
It is the last laminate one lays onto wet resin with a disposable fine hair roller that smooths out the resin and glass laminate to a VERY fair smooth surface.
Never needing to sand or wash off that aramine blush, or sand smooth your layup - cos it got messy huh?
Peel ply is invented for this. Believe me NO MORE SANDING.
Want a fair surface for looks? Just trowel on epoxy fairing you mixed up directly to that surface.
I have even applied peel ply to fairing mix..... with mixed results lol, see that epoxy gets runny'er as it sets, it generates heat that has it run a little, even under peel ply.... bugger.... well just trying to eliminate spending too much energy on that 2'6" X 8" long board!

A tip - cut with very sharp craft knife on MDF board, and in small say 2' x 2' pieces for large areas, and about 2" bigger than the glass you are to lay up for smaller areas like long chine runs etc.  much much easier to lay up, I covered the whole inside bottom planking with peel ply - beeeeautiful finish 
When you cut your glass prior to lay up, cut 20% in area more of peel ply.
I find having lots of various sizes of cut peel ply at hand for smaller areas to cover is economical.

I have used it twice IF when I peel (I mean pull off) it off, I lay it flat ready to use, but only really ok on larger flat areas, it's no good for curves or corners as it's been saturated with resin and thus stiff.
Here in Ozzie it's $2 linial yard, about 50" wide.

[Vicent59]

Do you use this product for all three layers or only for the last layer?  Thx.

[Ed Snyder]

Hi Vicent59,
I use peel ply every time a do a layup, so, if your only doing one layer at a time, in that this layer sets before the next is put on, then yes, use it for every layer.

If you lay up all 3 (or however many) then apply peel ply on the last laminate - layer.

I found cutting this ply into several sizes ready to use was the easiest, sizes - 1 ft sq - 6" x 12" - and strips to get those areas where the sizes above didn't cover or I miss placed - usually sized at 12 X 4".
Don't reuse them! I've tried 

I sometimes use peel ply when epoxy coating plywood, to both achieve a flat - non running epoxy coat and to avoid washing/sanding that film for the next process - undercoat for the final top coat.

Only use peel ply on resin be it epoxy, polyester or vynalester. (or however it's spelt!  )

Use a dry roller to roll it on and out, don't try to take it off if you don't get it in the right place ok, end up lifting the glass laminate too! Then what a plurry mess!