Polyester welder

I am looking for a source for a welding machine to seal pieces of
Mylar together at their edges to make an envelope, packet, whatever.
I have some oddly-shaped 2-D objects that don't fit very well in
standard envelopes from the conservation supply companies, and I
want to make my own. I know I can do standard encapsulation, but I
think the welding would be better for my needs.

I saw one reference to such equipment in a library supplies catalog,
but didn't know if there was anything else out there.

Melissa M. Heaver
Director-Museum Collections
National Trust for Historic Preservation
202-588-6148
Fax: 202-588-6232

                                  ***
                  Conservation DistList Instance 13:14
                  Distributed: Monday, August 16, 1999
                       Message Id: cdl-13-14-015
                                  ***