Vacuum former: update 3

An unexpected advantage to regularly posting updates is that I review my activities in a more detailed way. And so, when working on yesterday's post, I realized that I had glued the spacers on the wrong side of the platen! I rushed out to confirm my mistake, and sure enough, I had glued onto the working surface. Luckily, it turned out that the adhesive I used was terrible, and so the spacers fell right off.

So today, I cleaned off the glue residue from the platen, made some new spacers, and researched a good adhesive for attaching wood to metal. In the process, I discovered a great site called ThisToThat. You can put in two materials and it will recommend several appropriate adhesives. Between that site and some other prop building forums, the overall consensus was that J-B Weld was the right glue for the job.

J-B Weld for gluing wood to metal

I picked some up today and it is an epoxy. It comes in two tubes, one is labeled Steel and the other is Hardener. It's mixed in equal parts, however the result is much thicker than other epoxy I've used. It makes it harder to spread and so the application took much longer than I anticipated.

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Flattening the platen and applying pressure to the spacers while the epoxy cured.

I use shot for adding weighing to tool handles and playing pieces, and the bag of shot weighs a good 10 to 15 lbs. This is perfect for clamping down the wooden support spacers to the platen.

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The power cord to the shop vac is long, so I cut it in order to wire the vac into the controls and to provide the power cord for the entire vacuum former.

While that cured, I started work on the wiring. I cut the holes for the controls (fuse, pilot light, and 3 position toggle switch) and cut up the power and vacuum cables. I didn't get very far before I discovered some missing tools and decided to call it a night.

So, most of today was spent recovering from yesterday's mistake. I'll get back to working on the wiring in a couple of days.

Vacuum former: update post 2

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Channel mounts are complete with the oven aligned to the vacuum box.

I didn't get quite as far as I'd hoped this evening, but I was able to finish mounting the oven over the vacuum box. Now you can see the basic structure of the vacuum former. What's missing is the bracket that holds the sheets of thermal plastics. The bracket slides along the channels between the oven at the top and the vacuum at the bottom.

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Showing all 609 holes in the aluminum platen along with spacers that have been glued into position.

I also finished drilling the holes in the aluminum platen. In the picture you can also see that I've glued down supports that will keep the platen from sagging in the open area away from the support walls. I used a construction adhesive that's suppose to be good on metals and wood, so we'll see how it looks tomorrow. If the glue is solid, then  I'll use that same adhesive to mount the platen to the walls of the vacuum chamber.

I didn't get the chance to start work on the wiring, so that will have to wait until tomorrow. Also tomorrow, I'll mount the platen to the vacuum chamber and test the overall vacuum system.

Vacuum former: update post 1 (and some catch up)

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Aligning the vacuum form: the oven is positioned over the vacuum box at the proper height and aligned with the frame.

This is my first daily update, where I plan on documenting my progress on whatever geeky activity I'm working on.

My current project is a vacuum former. I'm enrolled in an online workshop put on by the Stan Winston School School of Character Arts and being taught by Fon Davis, titled "How to make a sci fi helmet.". The goal of the workshop is to create a prop that can be used in a movie or as part of a cosplay costume (I'm still uncomfortable with the use of cosplay as a noun), but the workshop includes building a vacuum former and showing how to use it. It's a tool I plan on using for my own prop making and costume building.

Fon Davis is a master model and prop builder, having worked on Star Wars, Matrix, Starship Trooper, Nightmare Before Christmas, and many other films and projects. We've had two of the three classes so far, and they have been AMAZING!

I haven't been very good about recording the last two weeks of work since I hadn't started this blog. So I'll give a brief recap with a few progress pictures (very few) and then document today's progress. Future posts won't be so long (I think...)

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The oven I used. You just see the sheet metal shell I removed when dismantling for parts.

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The key parts removed from the oven, although I won't be using all of them.

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The shop vac being disassembled.

In the last two weeks, I bought a toaster oven and a shop vacuum at Costco. These have been dismantled for the parts (see the pictures above).

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The oven box, but without the wiring

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The box that holds the shop vac parts and where the controls will go.

I've finished most of a heat box with the oven components that will be used for heating the thermal plastics. I've been building a box for the vacuum that will be used for pulling the softened plastics over the patterns (also called the bucks or forms). Both of these are shown in the photos, above.

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The shop vac is mounted, the base of the vacuum chamber has been built and sealed, and the switch plate has been installed.

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Current state of the platen; 126 holes to go...tomorrow.

Today I finished the vacuum box and worked on the chamber that distributes the vacuum over the working area. I also started work on the platen that is the base of the working area that supports the buck patterns. The platen is an aluminum plate into which I'm drilling 609 holes over a 1/2 inch grid. It's where the softened plastic gets sucked down over the pattern, creating the shaped item.

Finally, I worked on the mounting system that holds the oven over the vacuum (shown in the very first photo, above). When complete, I'll explain and demonstrate the operation, and why the major components are positioned and aligned the way they are. For now, the picture shows how I've used a pile of wood (of which there is no shortage in my shop) to set the height and alignment. Tomorrow I'll mount the channels (and buy the screws ... d'oh!), finish and mount the platen, and possibly start work on the wiring.