Cutting objects from Vacuum formed plastic.

[Vandark]

Hey there,

Can anybody please help?

I've just purchased a vacuum forming machine and had a go at duplicating a mask sculpture I did.

My question is, how do now cut the duplicate mask out of the sheet once its done?

it's got some pretty fine details around the edges.

any experts out there help me?

thanks

Richard

 

[Reactor drone]

If it has a flat base you can glue a sheet of sandpaper to a flat board and carefully sand down to the desired depth after cutting close to where the edge is.For 3D edges it's just a matter of careful use of files,dremels and sanders.

For my X-wing helmets I usually trim out roughly with aviation snips the finish off with an angle grinder with a sanding flap disk and a sanding block.

 

[giric thren]

For my ABS stormtrooper kit I use my Dremel...... in fact I havent found a job that the dremel couldnt do, AND I'VE TRIED. Seriously though buy a dremel, and a wand attachment (it is a must IMO), and practice, practice, practice. Then you will have wondered what peoply did with out it.

 

[hankey01]

Agree on the dremel comment. Use one of the cutting disks...take your time. It may melt a bit as it cuts but that will just pull off when it cools.

COVER YOUR EYES!

 

[actias]

Hi! I have done my own vacuumforming for years so I know the difficulty you're having. First I just score the plastic several times with a sharp Xacto knife. Run the score lines through the excess plastic edge to edge, getting as close to the formed piece as you can without damaging it. Then snap the plastic off as you go. Keep doing this until you are left with the least amount of excess plastic possible, near your part. Then use a dremel with a sanding drum bit to remove all remaining unwanted plastic. Smooth the edges by hand with a piece of sheet sandpaper. Works like a charm. I have successfully removed very detailed and odd shaped parts in ths manner - like removing excess plastic around the edges of an alien dome. That part has all kinds of odd dips hills any valleys to cut around. You will get a perfect trim everytime using these steps. Note: Run the dremel at a medium to medium high speed for the best results. Too fast and the plastic melts (this isnt a problem except that the fumes stink when the plastic melts and you might get a headache), run it to slow and it bogs down. Once you get it down, the process goes fast. Try the technique on scraps of styrene before doing the actual part. It's very simple. AND YES EVERY HOBBYIST, DO IT YOURSELFER AND MECHANIC MUST OWN A DREMEL. THEY ARE INVALUABLE. I OWN 3 OF THEM. Hope this helps.

 

[Contec]

Hurry and wish for a Dremel for chrismas present :lol
I started to cut my object with a carpet knife but it suxs and i had no control.
Dremel is a must in the prop making.

/Conny

 

[Vandark]

Thanks everybody for your help.

I'm new to prop building so i'm trying my hand at some different techniques.

I only got the machine tonight and it's a bit hit and miss at the moment, guess it just takes time and practice.

Guess i'll need to invest in a Dremel!! I actually got a hot knife, but it's a pain in the ass to use, keeps setting fire to the plastic.

thanks again

Richard

 

[Firefoxm31]

the trick i always used is a little less complicated....i gently hand sand from the inside along the interface of the part to the flange( the edge) and it pretty much just breaks away...try a couple pieces first as always til ya get the hang of it
Happy Holidays to all
Will

 

[ralphee]

If you struggle with the cutting disk (would be my first choice) another great method, is to tape an Exacto, to a flat support of the right height to your cut line, like a block of styrene or wood.

Place both on a flat surface (i use a big sheet of 10mm Plexi) and slide the block, with the exacto taped to the top, around your pull.

I used this to cut a few pulls on my Rebel Transport, works great, and you get a very neat cut.

lee