What's a dental vacuum former?

[GorFrag]

I'm looking to buy a small vacuum former and I keep seeing these "dental" vacuum formers for about $100 to $200.

https://m.usdentaldepot.com/Dental-supp ... s(-)U41157

It seems perfect for what I need. But can it handle styrene or other common plastics?

Anyone know?

[Rogviler]

Yes, they're just tiny, like 6"x6" or even smaller. I've seen people use them for modeling, especially things like cockpit canopies. Seems like it would be good for really precise and delicate parts.

-Rog

[GorFrag]

Thank you!

[Thom]

From 2014, but here is Adam Savage's review of the 'dental' vacformer, on Tested.
I'll be buying one, though they are slightly more than $120 now.


https://www.youtube.com/watch?v=RWxCvMzvxlQ

[southwestforests]

If all I knew about a dental vacuum former was that I had some modicum of familiarity with the English language I would expect it to be a device which forms a dental vacuum much like how a fuselage former on a stick and tissue airplane forms the fuselage shape.
Now, as to what a dental vacuum is and why one would desire to form one ... I dunno: it is Saturday and I don't have to know things on Saturday.

[mike robel]

If all I knew about a dental vacuum former was that I had some modicum of familiarity with the English language I would expect it to be a device which forms a dental vacuum much like how a fuselage former on a stick and tissue airplane forms the fuselage shape.
Now, as to what a dental vacuum is and why one would desire to form one ... I dunno: it is Saturday and I don't have to know things on Saturday.

[Andrew Gorman]

They are about the size of the old Mattel Vac-U-Form, which are not expensive now because of the interwebs. The Mattel I have works great the one or two times a year I use it and does not take up a lot of space. The upgrades from:
https://gaugepods.com/products/mattel-v ... s=e&_v=1.0
make the Mattel work a LOT better. I don't have a ChiCom dental machine so can't add anything about them- some people here have said they use them.

[jpolacchi]

Yes, they are small. I don't think they can form anything more than .010-.015 styrene.

[Zubie]

Anybody have any experience with doing canopies with this thing. I just got one from my dentist (thank you thank you thank you). He wasn't using it anymore so it's a bit dusty and in need of a cleaning.

Anyway, one of the problems with paper modeling is that outside of Luftwaffe type greenhouses, you can't really make a canopy from a paper pattern on transparency, so I was wondering if anyone had any experience doing this. I've heard (probably on this forum somewhere) that clear styrene sheets are actually not the best media for it. Would the old copier and laser printer transparencies work? I have quite a few of these from when overhead projectors were still a thing...actually even got one of those as well )

[jpolacchi]

I've read about others using that old Mattel toy vacuum former for making canopies.

[Andrew Gorman]

The transparencies for overhead projectors are very thin. Someone, maybe gaugepods, used to sell clear PVC punched for the Mattel machine but it looks like they no longer sell hose or the upgrade parts. the PETE used for blister packaging obviously works well for vacuforming and blank sheets and sheet protectors are available all over. Try what you have on hand and report back!

[Kekker]

If you want practice one, Michaels sells this: Memory Keepers Vacuum Former.

The bed is 5.5 by 5.5 inches, so not super huge. Fine if you're making canopies or smaller pieces. It's $142 through Michaels, or $88 through Amazon.

It comes with four sheets of plastic, but the replacement sheets are readily available, and you can likely use regular sheet styrene or PET which would be cheaper than the pre cut sheets.

You do need a regular vacuum with a hose to connect to it, and it has an adaptor for different size hoses.

Its crafting use would be for making molds for chocolates, soaps, or such.

[Andrew Gorman]

I just checked eBay and original Mattel machines are even cheaper than the Michaels product! (May 25, 2023)Repair and upgrade methods are all over the web, and upgrade parts are available. I really like my seldom used machine and it doesn't take up a lot of space.

[jpolacchi]

There are guys (sellers) also "claiming" to have modified those Matel machines that sell them on EVIL BAY for like $150-$200 I have seen. Buyer beware. Micro Mark sells the small dental ones and a slightly larger machine, but it seems a tad pricey to me.

[Andrew Gorman]

The usual modifications to a Mattel are pretty simple- a new perforated platform to hold your masters, a metal cover to help the heating element heat up faster, a little rubber one way valve, new rubber feet and some silicone grease for the vacuum pump. Some have bypassed the pump to connect a shop vac. They are simple machines. upgraded machines, upgrade parts and upgrade service are all by the same guy on ebay with positive feedback. Probably worth it if you are not mechanically inclined.

[Andrew Gorman]

I just fired up my upgraded Mattel for the first time this year and it worked fine pulling a form off of a resin master- the power bay boiler doors on a Revell XSL-01- a pretty simple section of a cone. First sheet of plastic drooped to far and contacted the heating element, so I had to use another pre-perforated sheet. This reminded me that you need to really let the unit get HOT before putting in the plastic. Took about 20 minuted to get good and hot with the aftermarket heater cover, but pulling the part was quick and painless after that. I like this little machine!

[jpolacchi]

If memory serves, you can really only form canopies or small, simple parts with .005-maybe .020 styrene on the modified Mattel former and about the same on the dental former? The forming space is maybe 3"x4"?

[Andrew Gorman]

it's limited, but doesn't take up a lot of space. Mattel platform is 2/12 X 3". I'm using some 1/32 inch thick PVC which is sturdy enough for my purposes. It seems about as thick as most vacuform kits I've built. Thinner plastic would give you better detail if that's what you need. If the part doesn't need to be clear just back it up with epoxy if you need more strength. The key is getting the plastic hot/soft enough to drape over your master and get pulled down. The GaugePods site says the when you add all the upgrades you and use up to 30 mil/.03"/1/32 plastic, which worked fine for me. I really like my Mattel hot rod for the very limited use it gets.
Updated link to the upgrade parts from GaugePods:
https://gaugepods.com/products/mattel-v ... s=e&_v=1.0

[jpolacchi]

Good reference to have. I've always wanted build my own vacuforming machine. Part of the problem is space for the size I'd like to have and getting a pump that won't bankrupt me. A vacuum motor only gets you so far, you just don't get the "pull" that a vacuum pump provides or the pull down in the time you need it. You wnat that, "quick" pull instead of waiting for a cheap vacuum pump that will take minutes to reach its full vacuum. I've looked at a number of options, different types of valves etc. Seems the best, most reliable system is a forming table with a tank to evacuate the air volume and all that has to be calculated out. The other problem is I'm not such a great electrician and installing reliable heating elements with temperature control seems problematic to me.

[Andrew Gorman]

A full size vacuform set up IS a lot of work. A good intro is this book:
https://www.amazon.com/Vacuum-Forming-H ... 5573&psc=1
And after that you need to experiment. Vacuum pumps are relatively cheap now and show up on craigslist. I went ahead and bought one off of Amazon because the stoner using theirs to extract pot resin never gave me a a time and a place to pick it up... Stoners. To pull a large object you need a decent pump and a vacuum tank- probably just a tire air tank would do, and for the heater a modified toaster oven would work. You are just creating a vacuum in the tank so a low CFM pump could work fine. The suction comes when you open the valve. From some staring at old vac models, a lot of them seem to made from female rubber/ polyurethane molds. That gives you some more wiggle room for shapes and undercuts. Look for some junk and see if it works. Try it out and have fun!

[jpolacchi]

I have that book. Read it from cover to cover. I know a tank is the best way to create the 29hg's of vacuum. You just need to make sure you have the right sized tank to do the job and there are other little tricks to reduce air volume. Basically, if I know I need to evacuate 4 cubic feet of air volume (that's all the air trapped between the frame holding the plastic, the mold, all the plumbing and the the forming box itself) I'm going to at least want a 5 cubic foot volume tank (or more). I prefer more actually. Its better to have more than not enough I.M.O. It was the electrician stuff to make the heater that I have a hard time wrapping my head around. Using my over isn't a viable option. Its best to have the heating element at the source and not that I'm trying to be, fancy" or anything, but having an ability to have some control over the forming temperatures would be a good option for me for forming different plastics of to pre-dry the sheet before cranking it up to forming temperatures.