How Do I Hot-Weld Clear 20 Mill Polyethylene Sheeting

Howdy BigEdm,

How many bags do you require?

Just the one for now. I need it to lay up 1/16" re-sawed cherry on 3/4" Plywood for several bedroom furniture projects. But the use of vacuum pressing has so may different applications such as curve forms, bent lamination, and I may need to make more as the need arises. I have enough PE to make 5 large bags.

You may put the layers on a solid surface, cover with heavy cloth then iron the edges.

You may use an orifice such as comes in a air bed and iron it in also.

If iron is not effective use a polymer type adhesive.

I have sealed smaller bags by setting a heavy object on top of a 16 gage wire then crossing 12V.

You are overcomplicating the problem for vacuum bagging. Take the poly sheets with overlap, and tape with a strong tape on BOTH side. That way one side will always be in suction, making the taping stronger.

To attach the vacuum line to it any kind of thick mastic, like fixing glass into a window frame is good: the vacuum just tries to make it tighter.

Obviously, you have to keep up the suction all the time, as the vacuum is not perfect, and some leaks exist all the time.

BigEdm,

The equipment you need for your project is commonly used by companies that construct HDPE liners for landfills. If you locate a contractor or HDPE liner supplier in your area they can help arrange a rental for you.

Good luck

Can anyone suggest the best adhesive to bond two pieces of poly together to make an air tight seam and still be ply-able (I asked the company where I purchase the poly from and they had no info on this). This may be the least expensive way to go.

Grizzly machines has a floor bag sealer for $200.00 but I don't think it would be hot enough to bond 20 mil poly together. I have talked to them and they said it may work but the manual was lacking enough info to be sure. This machine only makes a 14" long seam and would require multiple seams to complete the bag.

I have considered tape and would use as a last resort, for this may fail under multiple runs. If a taped seam should fail and bag lost all vacuum it may be to late if not caught in time to reseal bag, resulting in total loss.

An other option would be to make a table press. Not great for Irregular curves, good for flat panels.

Thanks for all the comments

Try googling 'master bond EP40

Great Info. Looks like this will work. I'll give this a try. Thanks a lot

Those guys are correct. They use this stuff to line and seal dump sites. They also use it to line pond. The following is a link of a plastic welding school

www.plasticweldingschool.org/pdf/TIPS-21A.pdf

This might give you some ideas. I think if you folded the seam and had an old adjustable soldering iron that has a wide flat tip, you should be able to weld it. The correct tempature is only about 270 degrees F. Therfeore you would have to have the setting on low.