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Working on the Lotus 15/R1. And I will need to find a replacment windshield. Ideas????? Looked into forming one but its like 40" wide buy 20". Alittle big for the home oven! Then their is building the buck. If I did build the buck and found a way to heat a 1/4" pice of plexiglass,what is the plug covered with? And it needs to be shinney and take 350 deg.
Thanks Randy.

Is it a simple curve? If so there are modern transparent plastics that are tough and strong, where 1/8" would be sufficient and no heating would be required. I forget the name but Chetcpo turned me on to one he uses in prosthetics...it starts with a V...dang, I can try to chase the brand down on the i'net, but I have a 4 x 8 sheet of it rolled up and stuffed in a trash can so I know it can handle the curve of a windshield wrap.

If you're doing a compound curve then it's going to be more challenging.

It looks to be,well complicated ,to say the least !

I'll ask my car club to see if anyone knows, Russ

Thanks for the help Russ.
Randy

So it does. I hereby declare myself No Help At All.

I take that back--give the Curtises* a call, I think they know a company that makes Plexi parts for vintage racers.

*707 443-8523

Thanks fpr the input and the help,Jack!
Randy

The acrylic is clamped in a wood frame suspended above the mold and just below the resistive heating elements.
The front screen mold (smooth wood with cotton cover/pad) is set horizontal, for an even stretch of the plastic.
The mold sits on a table with a matching frame and holes drilled around the inside of the frame but outside of the mold.
The holes connect to a manifold, connected to a vacuum pump like whats used for airconditioning systems.

Once the plastic begins to sag enough (experience), the upper frame is quickly brought down and the vacuum applied. Once it is cool to the touch, it can be removed.

Small parts do not need a vacuum table and special heating arrangement.

Track down the local experimental aircraft guys (the local EAA chapter) - they quite often form their own canopies.

So far my car club has come up with Bill Hutton. HME, Clarksville, TN. Russ

For a bubble canopy, the "table" is on top with the elements below. Instead of a vacuum, compressed air is forced into the sandwich above the sheet. The element should be height adjustable, to lower it away as the bubble fills.

You make the element from special wire (inconel if memory serves), ceramic isolators, and a large rheostat for adjusting the heat.

If the frame leaks, one has to keep adding air to maintain the pressure inside while also shutting off the heat.

You might also want to see if a local college or community college has a plastics program. I know the college I went to had a plastics program and they did vacuum molding.

Thanks for the ideas! Looking into doing it my self and also looking into the EEA. Thanks again.
Randy

please keep us all posted on how and what you do because it's a very important process for builders of midi's and the like using a fiberglass body, me for one

Will do!