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I would like to make a double back classical using sycamore and walnut. I have the quality vakuum ped vac which I would like to convert into a vacuum bag for laminating double backs. Do any of you know a good place to get a bag for this system ?. I think quality vak in mass. sells one but it seems high $$ . I/ve heard of joe woodworker and e- mailed them once with no info or response. I/m not sure of how to go about it. Your suggestions please Thanks. PS. Eventually would like to use the vacuum for sides as well

I haven' tried this yet, but I will relay what I read in another post on this site. A guitar back is relatively small and smooth and does not need a very strong bag, but make sure your backing board has smooth edges and corners, so they do not cut the bag. A plastic garbage bag is good enough. If you are worried that it is too flimsy, you can get heavy duty garbage bags or even heavier plastic storage bags at Lowes and similar stores. The storage bags are sold as something for long term storage of furniture. The bag is bunched up around the vacuum hose with a generous glob of putty such as you might use to temporarily weather proof windows in the winter. The hose and bag are secured with rubber bands. Because of the method of introducing the hose, my guess is that the garbage bag is superior, because it will bunch up better.

Thanks , anyone tried the garbage bags

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I make my own bags using thick vinyl sheet material from the hardware store. Buy a tube of vinyl cement(if none in the adhesives area, look in the swimming pool dept. for a pool liner repair kit; it will have the cement). Fold the vinyl sheet over, use a clothes iron to 'press' the fold, and proceed to cement and clamp the two open edges. Leave one end open to have access, and find a way to seal it. I cut a vee into a length of hardwood, and clamp a 1/2" dowel into the vee to seal the bag. I use a semi-truck(or tractor?) tire valve stem to attach to my pump. These stems are 2 piece and are threaded onto the tubes or tire rim; cut a small hole in the bag, apply cement to the interior piece of the stem and pull it through, apply cement to the outer part and thread it on, and clamp or weigh it down. Done! You now have a bag that will last for years, if not decades(I've been using mine for about ten years now). Cost? Less than $15 or $20...

Edit: you could also simply insert a length of vinyl tubing through a small hole and cement that in place instead of using a tire valve stem.

I have some adapters from my vacuum clamp that I could use as fittings to pull the vacuum out of the bag.Thanks for the DIY setup grumpy.

grumpy do you have any photos of your bag. ??Am not good at following directions lol Thank you