Homemade vacuum former

[JayAVFC]

Hi all,

has anyone ever made a vacuum former to make shells etc, im thinking of making one so I can make my own wings and shells to practice painting etc

I have heard it is quite easy to make one is this true??

Thanks all

[turok007]

many people make the unit then place it in the oven to heat the lexan then attach a hoover to it.   works really well.   loads of vids on the net. 

[JayAVFC]

Yeah that's what I plan on doing, I always snap 1/10th wings so should be good to make lots out of stronger plastic

[JayAVFC]

Ok all, so I made the suction section of the vacuum former and it works great!

So now I need to get plater to make a mound of so shell, what plaster should i be getting? cheap as possible please

[Tamiyacowboy]

Plaster paris buddy. 

 

now you need to mix it up and pour it into your mould ( ie an old shell )

 

there are 4 areas that need blanking out aka the wheel cutouts, so your plater reaches the very top of your shell mould.

then you have to leave it to set. 

 

after its set you can release the plaster from the shell, your now left with you mould for the airbed. 

 

to get your platic to release from the plaster mould good old johnsons baby talc is the key.

before you pull your mouldings, give the MOULD a good old dusting with talc, use hand and rub it over the mould.

place it on your airbed, and then pull your lexan mould, the talc will help the mould release more easy.

[Tamiyacowboy]

You want a few tools: 

 

OVEN GLOVES , i can tell you now, if that hot plastic touches your skin it will burn bad.

not surface skin but deep burns. SO YOU MUST WEAR GLOVES to remove the frame holding plastic sheet from a oven.

 

HEAT GUN, use this to help the plastic pull all round, sometimes you will find an area that just does not pull very well.

and sometimes we will place suction holes into the mould itself. we tend to do these on sharpe 90 degree angles/walls.

you place plastic onto the vac bed, hit the air-removal pump and let the plastic draw. keeping the VAC ON, you now

warm up the plastic with gun to get all the knooks and crags done.

 

BABY TALC !!!!, the release agent for the mould. 

 

PLASTER PARIS, always keep a little powder back from a mould making session. if your mould becomes damaged,

you have the medium to backfill and repair, a light sanding and a good drying out cure your broken mould is fixed.

use things like cocktail sticks to strengthen mouldings  that have corners snapped. mix your plaster paris fairly thick

beyond a yogurt like state to more a sticky gloop ( less water makes a more stiff mix . more water makes a runny mix for pouring.)

 

 

RUN TESTS !!!!! 

 

find something simple, i know grab a lump hammer and an adjustable wrench.

 

open the wrench as you would find it on the shelf in a shop, jaws apart, now place hammer 

and both wrench onto the bed. 

heat your plastic, and then pull a moulding. now if you find the plastic drooping and falling from the

moulding frame, use some adhesive tape on each of the four corners of the sheet plastic. it will help

keep it from slippings and sliding around.

 

the test run should show any need for improvement, ie more suction needed so you will seal the vac box edges and seems.

moulds with 90 degree vertical faces may find it hard to release its why we use the talc, but you also find that they can require

vent hold drilled through the mould so the plastic reaches all areas. its little things like this test runs will iron out.

 

if you have a large enough area and covered, its possible to build your own heatbox, a thermaly sealed box

that allows you to warm up the plastic in a more controlled manner using heating elements and controllers.

you open the door slide the mould frame holding plastic out and onto the vac bed direct infront and start the pull right away.

less time for the plastic to start cooling ( and you find it cools darn fast to so you gotta be quick )

Edited October 31, 2014 by Tamiyacowboy

[JayAVFC]

Hi, thanks for this help i will get on to it I just need to order some more lexan

[philuk]

where is the best place to buy the lexan,

 

i would like to make a canopy for an old morley bell 47G I have been restoring, but can't get a canopy anywhere

[Tamiyacowboy]

have a look for some 0.2mm or around that area thickness lexan sheet 

polycarb sheet. 

 

 

for a canopy you can use either foam block and carve/sand it down

 

for a super smooth detail version, use a couple blocks of balsa wood glued together with

pva. rough carve, then use a sanding to get your final finish.

using a dremal and sanding attachments you can pit areas out