Turbo's Vac Forming Guide

[Turbo Tax 1.0]

-Defined
Vacuum forming is an excellent way of making a case, it involves sucking a heated, flexible piece of plastic over a mold to form a desired shape or case.
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What is needed when Vac forming

A table, a major part of the process and there are many variations that are usable. (two are listed below)

-Studio Creations is a very simple table to make, I have used this table in the past it has no heat source and it involves heating the plastic on a simple rack in your oven. The guide explains it all even making a mold.
Cost= very low

-Rhalis Kahn's guide is a very extensive one that explains how to build an awesome table. I recently built this table and it works great. This table has its own heat source suspended above so all you need to do is let go of a few clips, slide the plastic down, and turn on the vacuum.
Cost=kinda expensive but worth it if you plan on making a bunch of cases
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plastic
Polystyrene is recommended at a thickness of ~.080 centimeters.
I have read that ABS plastic is also usable, it is apparently more brittle and harder to work with though.

good prices, the link has some good prices for styrene if you can't find any just click on the ".080 high impact styrene" thats what you'll be wanting.
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mold
Needed to form over, it should look like what you want your case to look like, except be several inches thicker, or else it is a female of the dog species to form over .

can be made of

-Plaster, very simple guide below, yields good result sometimes a little rough but can be sanded when done.
1.make a clay mold of what you want your case to look like (several inches thick no matter what the desired thickness is)
2.cover that clay mold in a plaster cast pretty thick maybe 1/2 an inch
3.once it dries take the clay out, grease up the cast with whatever (vaseline worked best for me)
4.then fill the cast with plaster
5.after that dries (let it dry overnight make sure that it is dry)
6.snap off the edges of the cast with your hands to try and get the cast off of what should be a plaster form of your original clay mold


-Wood, Marshalh had this awesome idea I tried it out and loved it. It gives you a very smooth very nice mold, you will need some wood working tools to do this.

1. draw your case design on graph paper to make sure both sides are symmetrical
2. cut out the design with an X-acto knife, but cut out slits near the edges also (then set this aside for a little while)
3. glue together some wood and make sure it is a few inches thick (~2)
4. once it is dry tape your design you cut out earlier onto the wood you just glued together, you should be able to tape it on through the slits you cut near the edges of your design in step #2
5. trace your design onto the wood with a pencil, try to make it as noticeable as possible. then you can remove your design
6. cut the design out of your wood with a band saw
7. bevel the edges with a router to give it a nice rounded feel
8. sand it with some high grit sand paper

before you form over wood make sure that it is well lubed
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bondo
bondo is used to add things like controls and screen holes to your vacuum formed shell, dkaps portables at www.davesportablesystems.net have bondo in them

I reccomend a two step bondo proccess
1. start off with bondo marine putty to fill in all of the bigger holes, sand this with lower grit paper
2. go over it with some bondo spot putty for a nice and smooth finish, sand this with very high grit sand paper, i usually go over it with steel wool after i sand it to get it real smooth
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Backs
to make a simple back to your case

1. trace your case on a sheet of plastic
2. cut as close as you can to what you traced except try and make it slightly larger
3. drill holes where you want to put your screw posts (for screw posts I have used screw posts from the console I have gutted, or wooden dowels)
4. place your screws in the holes you have drilled
5. screw your posts onto them (not to tight) while in the plastic
6. place your back on to see if the screw posts will fit inside
7. heat up your hot glue gun and load glue onto a screw post then put the back on the case again
8. once it dries carefully unscrew the screw from that post and load it up with hot glue or epoxy
9. once that dries loosely put the screw back in the post with your hand, so you can still lift the back off the case and put more glue on the other posts
10. then go crazy with the glue on the other posts, wait for them to dry
11. then carefully take the screws out of them and load them up with hot glue

Now you should have a back that you can screw onto your case, but wait it still should look kinda funky cause it doesn't fit right.

12. once the back is completely secure on your case sand it so it is flush with your case
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Any opinions, suggestions, or corrections would be greatly appreciated

Made sticky by request of author and for the forum's benifit. - Sparkfist

[Dilberitio]

Okay,this is very noobtacular,but I have to ask it.When you put the plaster on the clay to make a mold do you fire the clay before putting it in the oven

[Turbo Tax 1.0]

you dont put the clay in the oven at all, you get rid of the clay mold after you make the plaster cast


if your talking about forming over a mold im guessing your talking about the studio creations table. i'd suggest reading over the sight again.


you put the plastic in the oven, take it out, put it over your plaster mold and them turn the vacuum on quickly.

[Dilberitio]

Is there anyway you could make the bondo section more in depth; I have no clue what it's for, how you use it,and some pictures would be nice if possible.

[Dilberitio]

Sorry for the double post,but for the table where did you by a reducer nipple.And what the heck is that circular fitting that screws onto the table called?

[Turbo Tax 1.0]

Is there anyway you could make the bondo section more in depth; I have no clue what it's for, how you use it,and some pictures would be nice if possible.

yeah i'll make the bondo section a bit more in depth, i'll just make another thread and make a link in this thread.

Sorry for the double post,but for the table where did you by a reducer nipple.And what the heck is that circular fitting that screws onto the table called?

i could not find a reducer nipple, so i bought a hose to hose connector. drilled one huge hole in the board then hot glued and caulked it on

[Master of Portables]

i have one question, when the mold has a piece of wood that is a 90 degree angle, will the plastic form and make a straight edge, or will it have a tiny curve between the angle sides

[Turbo Tax 1.0]

do you mean the plastic forming around a corner like around a square or like the inside of a "T"

if its in a "T" it's probably gonna bunch up at the corner a little bit. and if it is like a square you will get some bunching about a cm down the mold


try and avoid sharp turns in molds if you know what i mean

[Master of Portables]

oh yeah, i found a mistake, the link for the studio creations is the wrong one,. it should be the tutorial for MAKING the vac forming table not the one on how to use it...

[Turbo Tax 1.0]

oh yeah, i found a mistake, the link for the studio creations is the wrong one,. it should be the tutorial for MAKING the vac forming table not the one on how to use it...

cool i'll edit it in a minute

[Master of Portables]

another question, would say bondoing a piece of plastic to the mold to give it shape work? and if it is something like a controller would the button holes mess up the plastic forming around it like making it uneven in that area?

[Turbo Tax 1.0]

you wont get the same sharpness or look as if you just bondoed it to the case.

but you should get some semblance of th original controller

[jeroen]

another tutorial. http://www.alstevens.com/ventriloquism/vacuum.html

[Life of Brian]

another tutorial. http://www.alstevens.com/ventriloquism/vacuum.html

Cool! Thank you for posting that!

[drcrash]

I posted an article over at Instructables on how to make a good, cheap, upgradeable vacuum former:

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

The design is particularly appropriate for case-modding, unlike most vacuum formers that are for lightweight model parts or costume armor or whatever. For sturdy cases, you want to use thicker plastic.

For that you want to add a high vacuum system that pulls several times harder than a vacuum cleaner, and for that, you need a vacuum pump.

You can make a vacuum pump for under $20 from an old-fashioned bike pump:

http://www.instructables.com/id/EA58LR1F35J1I9N/

A few minutes of pumping will let you form plastic 3 times as thick and about 30 times as rigid. You don't want to do that a bunch of times a day, but for case modding you generally don't need to. (And if you do need to, you can make an electric vacuum pump for about $30.)

For more info, see my new web site, www.VacuumFormerPlans.com . It has links to a bunch of stuff about doing pro-quality vacuum forming on the cheap.

BTW, I highly recommend Doug Walsh's book "Do It Yourself Vacuum Forming for the Hobbyist." (You can get it from his site, www.build-stuff.com ) I've reinvented a bunch of his wheels, and reading his book sooner would have saved me a lot of time and effort.