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[wouter]

hello all
have tried the bubble wrap as a breather
found it to suck
all the resin and air bubbles stick in between the bubbles.
any good solutions or tips?
wouter

[Jarrod]

If the resin is getting on your breather material, then you're missing a layer...

My vac bag has a permanent installation of some thick felt-like material running the full length taped to one side.   Before going in the bag, the whole board gets wrapped tightly in release film, that's what keeps the resin off of the bag and the breather material.

[surfer_dave]

if the resin is getting to your breather, you're using too much resin imho... when I vacc'ed mine the balsa skin remained pretty much dry, only one or two leak throughs, I've been lucky  I guess but I kept resin quite low during skin lam, everything moist, nothing soaked.

[Bernhardt]

For breather.. some of us use black plastic shade cloth from the hardware store

for peelply/perforated release which sounds what I believe you are using the bubble wrap for..
go to the local  seamstress store and find some nylon liner for dresses that breathe. It's cheaper than the commercial products we get from vacuum bagging suppliers and allows the resin to be drawn out of the laminate into some form of blotter material like paper towels or cotton batting.

from what I understand breather just allows for the proper compression of the bag and not necessary to resin draining although bubble wrap can be used for that. brether is usually applied to the opposite side of what you are compressing to the core and allows for airflow down the length of the object.

I don't like bubble wrap as it tends to leave indentations in the final product no matter how small the bubble.

I do use it as a strip down the middle flat side down when bagging on the deck skin to help apply pressure on the compound curve of the deck rocker curve while the bag pulls down the rail curve.   

Update:
this is how we were taught and how tom sullivan demonstrates in his video on vacuum forming sailboards..
but when bagging on your skins, we use a thin 2mil-3mil ply of stretchable poly over the skin which we wrap around and pull tight using tape on the racks to hold  and compress the skin material over the from. This is the same poly we used on the glassing table to prewet the glass onto the wood (never on the foam).

You can use this same technique to glass your board in a vacuum bag where you would use some sort of peelply/blotter to extract off the excess resin. What sullivan does is that once the thin poly wrap is pulled tightly over the glass, he goes around and punctures holes in it to allow it to breathe and let any air escape that might come from outgassing. he then covers this in blotter before puttin it in his bag. But a eminder, your glass job must be done, squeegeed out and pulled tightly before applying this plastic bleed through layer .. How they can do it on both sides at the same time before bagging it is beyond me. Exterior hand lams are so much easier.

The poly/release wrap keeps the resin from getting on your bag and the shade cloth is taped onto the inside of the bag and used between the bag surface and the taped poly side allowing the bag to compress tightly against the side your lamming.  We also use a shopvac with an PC keyboard cleaning adapter to suck down the bag instantaneously to prevent shifting before clip sealing the bag and hooking it up to the vacuum reservoir. This way the vacuum tube bag and the shade cloth never touch any of the resin.

[Benny]

I agree with that, but I'd remind everyone to test your shade cloth first.  I bought some green & black stuff from Ace Hardware and it happened to get very cozy with one brand of epoxy. 

It was like picking cat hairs out of your newly-varnished wood furniture masterpiece.  I've been there too (damn cat  ) - no fun. 

Never used bubble wrap. 

The dressmakers' nylon is great for letting out excess resin, and I use those blue paper towels they sell at the auto parts store over it as absorbent.  Only thing is, with too much pressure, I actually sucked out too much resin once and got a laminate over the balsa that looked like white window screen.  Wasn't really attached to the wood - the resin found it easier to go through the nylon into the towels than it found it to penatrate the smooth balsa...

[Benny]

I agree with that, but I'd remind everyone to test your shade cloth first.  I bought some green & black stuff from Ace Hardware and it happened to get very cozy with one brand of epoxy. 

It was like picking cat hairs out of your newly-varnished wood furniture masterpiece.  I've been there too (damn cat  ) - no fun. 

Never used bubble wrap. 

The dressmakers' nylon is great for letting out excess resin, and I use those blue paper towels they sell at the auto parts store over it as absorbent.  Only thing is, with too much pressure, I actually sucked out too much resin once and got a laminate over the balsa that looked like white window screen.  Wasn't really attached to the wood - the resin found it easier to go through the nylon into the towels than it found it to penetrate the smooth balsa...