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drcrash
07-10-2007, 12:37 PM
(Sorry, I seem to have screwed up editing this post and lost the original text... this is a rough reconstruction. See the movie in a later post.)

I wrote an "Instructable" on how to make a good cheap upgradeable vacuum former using your kitchen oven and a vacuum cleaner:

http://www.instructables.com/id/E8RW98YF3C4XLCQ/

You can also make a high-vacuum system for it, using a converted bike pump, to get finer detail with thick plastic, for about $50, or add a standalone oven for about $30. The high vacuum system can use a converted bike pump or a thrift-store tire inflator, nebulizer pump, or kitchen food sealer. (For volume production, you'd want to have a "real" vacuum pump, but for making a few sturdy cases, high vacuum can be cheap.)

http://www.hackaday.com/2007/07/01/vacuum-bike-pump/

This stuff and more is linked at my new "Vacuum Former Plans" web site, www.VacuumFormerPlans.com

tybrenis
07-10-2007, 12:46 PM
I recently made a vacuum former myself using nichrome wire heating elements and a dual shop vac vacuum system - it was very strong and could form plastic up to 1/4" thick.

drcrash
07-10-2007, 01:51 PM
I recently made a vacuum former myself using nichrome wire heating elements and a dual shop vac vacuum system - it was very strong and could form plastic up to 1/4" thick.

I saw the thread that stopped about a year ago, but nothing since then.

Did you post pictures and stuff somewhere?

If you add a high vacuum system, you'll get better detail. (If you need that.)

drcrash
07-18-2007, 01:12 PM
I made a video of using the vacuum former from the Instructable:

hGBRiYhxRTM

tybrenis
07-18-2007, 01:20 PM
I never really posted pictures of the final vacuum former - my computer is for some reason not allowing me to upload photos anywhere online. Its a big problem for me, otherwise I'd show you the pics. I honestly haven't even been thinking about modding much lately so the vacuum former has been sitting unused for a while now. However, I tried it out with a second shop vac I recently got, so with two 6.5 horse vacuum the thing was incredable. I could actually hang from a sheet of plywood with two handles on it being held by the vacuum.

Zephik
07-18-2007, 05:44 PM
Ha! That video was awesome! I don't think I have a _real_ need for vacuum forming, but hell, that looked like fun! Can you say.... self made Halloween masks? :p

Tybrenis... what HAVEN'T you made?? lol I mean jeesh, From your own case mod to a cnc machine to a vacuum former to a heat strip for bending plastic to a etc etc etc.

Whats next? Your own custom Unicycle? ...oh hey... a cirque du soleil themed unicycle! :D ;)

tybrenis
07-18-2007, 05:54 PM
Ha! That video was awesome! I don't think I have a _real_ need for vacuum forming, but hell, that looked like fun! Can you say.... self made Halloween masks? :p

Tybrenis... what HAVEN'T you made?? lol I mean jeesh, From your own case mod to a cnc machine to a vacuum former to a heat strip for bending plastic to a etc etc etc.

Whats next? Your own custom Unicycle? ...oh hey... a cirque du soleil themed unicycle! :D ;)

I also have absolutely no need for a vacuum former. It was just cool to make, lol.

Actually, my current project is replacing all of the furniture in my bedroom with my own, hand made solid cherry pieces.

drcrash
07-19-2007, 02:01 PM
I'd be interested in info on how to make a good cheap strip heater.

I've been thinking I can modify my hot wire foam cutter design a little bit and make a nice one with heat control for about $20 (not including a car charger to use as a high-amp transformer)... but I'd like to see what others have done.

I saw "Tim"'s strip heater in Tybrenis's build log, and it looks a whole lot like what I've got in mind. (I'd probably use stainless steel fishing leader instead of nichrome.)

drcrash
07-19-2007, 02:21 PM
I could actually hang from a sheet of plywood with two handles on it being held by the vacuum.

With a high vacuum system---even a converted bike pump---you get several times as much forming force, and could hang your whole family, or maybe your car. :twisted: (Briefly, but long enough to suck 1/8" or 1/4" plastic into tighter radii.)

tybrenis
07-19-2007, 04:11 PM
I'd be interested in info on how to make a good cheap strip heater.

I've been thinking I can modify my hot wire foam cutter design a little bit and make a nice one with heat control for about $20 (not including a car charger to use as a high-amp transformer)... but I'd like to see what others have done.

I saw "Tim"'s strip heater in Tybrenis's build log, and it looks a whole lot like what I've got in mind. (I'd probably use stainless steel fishing leader instead of nichrome.)

Basically the same thing.

moon111
07-22-2007, 07:26 PM
I use to work in orthopaedics/artifical limbs/etc so I have lots of exposure to vacuum forming. One thing we did on smaller casts of amputed limbs, feet, etc was wrap them in industrial nylons. This would allow vacuum to get into every crack and crevice so there wouldn't be any air pockets. On Larger casts such as a whole back brace we'd insert a large 4" pipe covered in vaseline so we could rotate the cast while we worked on it.

Well one day we ran out of supplies, so there I was running across to the department store to buy their entire supply of white nylons and three jars of vaseline. Trying to explain to the cashier did no good. I've never shopped there since!

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Anyways, I'm going to use this occasion to show how to make yourself the most confortable pair of 'MODDED' insoles.

STEP 1:
-Buy the softest foam you can that's used for making flower arrangements. (Some brands are too stiff... I bought mine from a dollar store)
-Cut in half. They're too thick.
-Place in box so they don't wander when you step on them.
-When stepping down, realize this foam is more dense then the stuff they
really use so you might have to make sure you put enough pressure down.
-Next pound the area where the toes are... you want this flat. (Toes are suppose to wiggle, not be held confined.)

http://img.photobucket.com/albums/v282/moon111/Foam_readyforpouring.jpg

STEP 2:
-Mix up some plaster and pour it into the molds.
http://img.photobucket.com/albums/v282/moon111/Plaster_of_paris.jpghttp://img.photobucket.com/albums/v282/moon111/poured_molds.jpg

-Once hard, break the foam off.
http://img.photobucket.com/albums/v282/moon111/Cast_removed_from_foam.jpg

STEP 3:
-Shape using a body-filler file.
-Smooth out using a piece of screen (the stuff for keeping bugs out) and some water.
-Note: It's allot easier to take plaster off then to add it.

STEP 4:
-Build a box with a false bottom. Hook up a vacuum to compartment underneath. Drill holes to let vaccum through.
-Using a piece of plywood similiarly shaped as the mold will help get a good
vacuum on it.
-Put 1st layer of craft foam on a sheet. (I've also used larger insoles and trimmed them once done, but found they shrink and get slightly harder.) Heat 1st layer in oven. (Old toaster ovens can sometimes be big enough for this.)
-Put 1st heated layer on mold, with vacuum going, cover top of box with a
garbage bag. It'll pull the foam down.
-Let cool, don't remove.
-Glue and heat up a second sheet if one isn't thick enough. You might also have to glue pieces to fill in the arch area.

STEP 5:
-Once done, I use an existing insole and a pen to trace out the shape. Cut excess off with knife. A bench grinder would be great, but I've used my belt sander turned upside down to grind edges down.

***WARNING***
As with any foot product, if you suffer from bad blood circulation, diabetic, etc... a foot infection, calluses, ulcers, etc an lead to problem such as amputation. If it rubs, don't wear it.