Ive got a few ideas brewing about laminating my solid paulownia project. Im trying to avoid using big 20+ inch clamps as they are expensive and tricky to use on the next part of my project - glueing the shaped blank back together after chambering (clamping the rounded rails seems to be the tricky part). Ive tried using old bicycle tubes but they dont seem to give enough pressure to connect the timber perfectly as its not completely straight.
anyway I thought vacumm bagging would be a good way to do the glue up.
Ive used the Roarockit hand pump system with building skateboards before and it worked quite well. With a good seal, the vacuum would easily hold for hours at a time. My bag has since lots its perfect seal and i thought the next logical progression would be to get a pump which would keep the vacuum continuous.
has anyone tried anything like this? I would be keen to hear if it has worked. it seems so simple.
a couple of thoughts/questions -
would the pressure from a thinner garbage-like bag be as much as that of a thicker nylon tubing type bag? Im thinking yes it would as long as the vacuum is the same in both cases.
would a thicker bag have less leaks?
given that Ive been able to easily laminate and bend three pieces of 2mm bamboo ply in a hand pumped Roarockit bag that has no continuous vacuum, it seems as though it would be possible to use this technique on a surfboard.
and another thought i had at the supermarket picking up a vacuum sealed pizza, what about creating a perfect vacuum seal like they do on all of these food products? Surely it would be possible to do it on a surfboard?
any ideas on the tools/heat seal methd used to seal a bag permanantly and remove the air at the same time?
would a thicker bag work “better”? The only quality of a bag is that it doesn’t leak. To the extent that a thicker bag might be more durable, then a thicker bag is better, until it leaks. I think transparency would be a plus, too.
The only concern about how much pressure is exerted is how much vacuum you pull. Making paths inside the bag for any air pockets to be sucked down is mandatory.
I suspect the supermarket bags such as for bacon, etc. are drawn down with a “wand” or suction line that is withdrawn from inside the bag, as the bag is sealed at its edges by heat (perhaps using microwave energy). Heat sealers are not uncommon household items, though their day, if they had one, was probably several years ago.
Don’t go fancy, just get something that works. See elsewhere in the archives, there seems to be a limit how much vacuum you want to pull.
As for putting your chambered wood back together, alignment is critical. Clamping pressure is not. You just want to stick the sticks back together enough to fine shape, and for that I’d think it needs to be out in the open where you can see it and adjust alignment. I read that you want to do two adjacent sticks at a time, and I’d think you want to start from the center and work outward. The strength comes from glassing, and for a wood board, I don’t see why you’d want the trouble of vacuum bagging. just a plain 'ol two-on-the-top, one-on-the-bottom lam.
love to take this with me traveling with a portable hand pump
But a great way to put on skins and rail bands without electricity
with this and my battery powered planer,drywall saw and a bottle of 5 min epoxy or gorilla glue and I can make a wood skinned EPS composite anywhere in the world (New Guinea?)
check out the instructional video, its classic. I think your comment honolulu about household vacumm sealers having had their day several years ago is expresed well in this video!!
i just ordered a bag button anyway as i figured i would use it around the house even if it doesnt work for surfboards.
Ive been googling a bit of info on how to seal bags airtight (which is critical if you dont have a continuous vacuum). So far Im thinking the best way would be to get my project in a PE bag, heat seal it so there are no leaks and then use something like the pump’n’seal to get the air out and pull a vac.
Im not opposed to using a proper vacuum pump as it is obviously a proven method, but i just keep thinking that there could be a simpler and cheaper way.
anyway, im excited by these ideas so ill be having a crack at them. Ill let you know how they go.
