How to make a vacuum/envelope bag in a pinch?

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#1

I’m in a pretty bad spot, I have a few personal parts id like to make by the end of the week but i ran out of supply. I normally use bagging tube with 2 clamps but my restock order wont arrive until monday…

Is there a way i can rig some supplies up from local stores to make some bags? i only have about 2 rolls of sealant tape left(25ft each) so i really would like to conserve it… can i use plastic drop cloth from home depot? (i believe i read that somewhere… majority of the pieces im making are flat panels, U shapes (3 walled, 90* bends) also is there an alternative to the tacky tape? maybe gorilla tape to make the bag/envelope?

I need some old school methods and home made receipts if anyone has them! thanks!

#2

butyl sealant from a cartridge. Or look for body shops (trucks, vans), they sometimes use butyl tape for anti-rattling, holding panels, etc.

#3

You can get butyl tape in the roofing section of Home Depot, its used to seal the joints of metal roof panels. They obviously also have a large selection of plastic sheeting trial and error may be the best way to pick one of them.

#4

Yeah used that roofing sealant tape in the past, does the job very well actually.

#5

check out pond liner tape…it is thin, but kind of like tacky tape.

#6

Floral supply houses sell the exact same tape, I think they call it “cling”. My wife gets it all the time and I can’t tell the difference.

Jon

#7

nice thats perfect! what about bagging material? ive heard people using the 2 mill drop cloths with success?

#8

Problem with agricultural films and the like is that these are single layer, and PE. This sometimes causes a hard spot or a pinhole, which is of no problem for normal uses, but we plasticheads are not normal…

Most vacuum films are multi layer, or at least nylon which pinholes less (and during production there is a much closer tolerance)

#9

I bought a commercial product, PE single layer from McMaster (similar to what you could buy a a hardware store for drop cloth). I ruined two infusions from a tiny pinhole. I tested more of the material. It has tiny pinholes all over it, probably one for each 10 square feet of film. Not worth trying to use it.

#10

Another alternative to the tape is a product called Moretite caulking cord. I’ve used it many times and you can get a perfect seal with it. It costs about $6.00 for 90’ and is reusable. It is also very flexible so going around coner is no problem. My .02.

#11

dang that stinks… i have some 2mil drop cloth from HD… maybe ill just try a sample bag…

as far as the butyl tape… i got it, but its like 8"wide which is cumbersome to use… i was thinking about using a sawzall to cut it in a 1" thick roll… any suggestions on that?

#12

The butyl tape at Home Depot I have seen is gray and only about .5" wide and comes on rolls that look almost identical to actual sealant tape.

#13

You can also seal it by heat welding it with a soldering iron and baking paper.

#14

hmm. i only saw like 6" and 9" rolls… i actually just dealt without it and did a wet layup…:frowning:

ah yes! why didnt i think of that… ive watched your videos a few times the past couple of days… actually looked through a few of them on your vimeo account… wish you did the series! i woulda loved to see the various mould techniques you briefly spoke about

#15

Where do you buy your bagging tube?