Home Made Vac Former - Forming RC bodies

[yogi-bear 2321]

some minor update:

 got the control panel made and on. All switches are working as they should, but the valve to the pump is a bit restrictive, so a bigger one is on order. Still need to install the new pump and redo the base. Hoping to do a test form next week though.

 

also got the digital readout for the z-axis installed today

and the stepper motors for the milling machine arrived today, these are about the size of a fist.

 

lathe also got put back together today

 

[Re-Bugged 10155]

On 1/22/2020 at 9:29 AM, Incredible_Serious said:

Glad to see you're still at it, mate... only taken me about a million years, but I'm just about finished my first of your shells....

Just the head and tail lights to do, plus some minor details.... and trim the rear body mounts. Still, progress!

Look forward to your new releases... lol... quick vac-forming joke 

Alex

Very nice 👍🏻😉

[yogi-bear 2321]

3 minutes ago, Re-Bugged said:

Very nice 👍🏻😉

I'm hoping once the setup is improved I can get a better version (no webbing mainly), but only in PETG and ABS, polycarbonate is still going to need a few more modifications to the heating system

[yogi-bear 2321]

ok, finally an update. This week I managed to get to test the updates and I'm pretty happy with the results. The material is HIPS, which isn't really great for a basher body but easier to form than ABS or polycarbonate. One of my biggest issues was getting a proper seal, so that's all sorted now, and next week I'll try ABS. Hopefully I can get some more 1.5 mm if not it'll have to be 2 mm thick. And this even worked despite one of the elements shorting out and overloading the circuit (since disconnected)  .

 

 

[mtbkym01 4008]

Hat’s off to you my friend, you really are a man of many talents, top stuff !

[KalEl63 695]

26 minutes ago, mtbkym01 said:

Hat’s off to you my friend, you really are a man of many talents, top stuff !

I fully agree with you bud

[Superluminal 3750]

Hello - just bumping your thread after seeing your cockpit moulds in the latest build thread.

Ive been after a group-c cockpit for a while and slowly thinking im probably going to have to make one from scratch. I like the idea of vac forming something and have one i can take some moulds from as long as it doesnt damage or effect the one i have already (as its painted) what was that grey coloured resin you used called? Does it come out from the original easily without affecting it? As the originals are pretty crappy thin plastic.

[Incredible_Serious 107]

Looking forward to seeing updates for this over the next few weeks.... come on @yogi-bear, let's see some more magnificence! What else is Christmas for???

We can go head-to-head, see who can complete the most. I've still got to finish up the last few details on my Mk.1 Escort..... but sadly, my money is on you 

Alex

[yogi-bear 2321]

2 hours ago, Superluminal said:

Hello - just bumping your thread after seeing your cockpit moulds in the latest build thread.

Ive been after a group-c cockpit for a while and slowly thinking im probably going to have to make one from scratch. I like the idea of vac forming something and have one i can take some moulds from as long as it doesnt damage or effect the one i have already (as its painted) what was that grey coloured resin you used called? Does it come out from the original easily without affecting it? As the originals are pretty crappy thin plastic.

the resin was the cheapest I could find from the auto store, when I get home I'll take some pics. You do have to be careful and I nearly ruined the cockpit I took the casting from, mainly because it stuck to the cast. I didn't use enough release agent and some resins will need a specific release agent. Yeah, they'll be thin styrene, as they are non-structural items, so don't need to be anything special. It makes them easier to form too. I'll be doing some vac forming of these next week and will re-do the casting process as I didn't take any photos. It's pretty simple though. Do you have a vac former? if not simple enough to make a basic one, especially if you using styrene.

 

21 minutes ago, Incredible_Serious said:

Looking forward to seeing updates for this over the next few weeks.... come on @yogi-bear, let's see some more magnificence! What else is Christmas for???

We can go head-to-head, see who can complete the most. I've still got to finish up the last few details on my Mk.1 Escort..... but sadly, my money is on you 

Alex

I'm trying! I like a good bit of competition, hopefully I'll get a few things done . I've also found a supplier for 1 mm polycarbonate, so will be giving that a go too.

[yogi-bear 2321]

40 minutes ago, Incredible_Serious said:

Looking forward to seeing updates for this over the next few weeks.... come on @yogi-bear, let's see some more magnificence! What else is Christmas for???

We can go head-to-head, see who can complete the most. I've still got to finish up the last few details on my Mk.1 Escort..... but sadly, my money is on you 

Alex

oh, I have some 0.375 mm lexan too, I could re-do the windscreen on your Escort. From memory it was a little rough.

[Superluminal 3750]

Dont have a vac former yet but thought it might make a christmas project, your work is really inspiring with whats some readily avaiable diy type items and your results are great. Unfortunately i dont have a spare sacrificial cockpit either that i can take a mould from and risk damaging it - it would need to go perfectly well first time or im going to be looking for two more sets!! Dont think i have the big brave boy pants to risk that!!! 

[yogi-bear 2321]

1 minute ago, Superluminal said:

Dont have a vac former yet but thought it might make a christmas project, your work is really inspiring with whats some readily avaiable diy type items and your results are great. Unfortunately i dont have a spare sacrificial cockpit either that i can take a mould from and risk damaging it - it would need to go perfectly well first time or im going to be looking for two more sets!! Dont think i have the big brave boy pants to risk that!!! 

I've seen some clever, yet basic cockpits made from wood. You could probably give that a go, low risk!

[Superluminal 3750]

2 minutes ago, yogi-bear said:

I've seen some clever, yet basic cockpits made from wood. You could probably give that a go, low risk!

Thats not a bad shout actually! The group c cockpit is pretty basic apart from the seat and steering wheel but i can probably take them from a buggy driver figure.

[Incredible_Serious 107]

3 minutes ago, yogi-bear said:

I'm trying! I like a good bit of competition, hopefully I'll get a few things done . I've also found a supplier for 1 mm polycarbonate, so will be giving that a go too.

Oooh.... them's fighting words!!!!! If I had the paint, I'd give the Mk2 I have from you a go.... but it's PETG from memory, and I don't have the correct paint . I do have quite a few projects on the go at the moment.... so... 

[yogi-bear 2321]

11 minutes ago, Incredible_Serious said:

Oooh.... them's fighting words!!!!! If I had the paint, I'd give the Mk2 I have from you a go.... but it's PETG from memory, and I don't have the correct paint . I do have quite a few projects on the go at the moment.... so... 

I think I just used acrylic based paints on the ones I have. I should send you a ABS version, easier to paint. I should have a couple spare in the next week or so.

[Incredible_Serious 107]

1 minute ago, yogi-bear said:

I think I just used acrylic based paints on the ones I have. I should send you a ABS version, easier to paint. I should have a couple spare in the next week or so.

I pretty much have only Tamiya PS rattle cans in the paint box.... makes it kind of limiting, for anything other than lexan....

I probably should send you something back for the bodies you've already sent, before you send more ... besides, you'll be flat out pumping out RHD rally cockpits soon, so best to keep on your good side... 

Alex

[yogi-bear 2321]

ok, so my Christmas project is to do some vac forming. First on the list is to get some more sheets. I managed to find some 1 mm polycarbonate (something I couldn't get last time I tried). But that will have to wait until I improve the heater box. I also bought ABS at 1 and 1.5 mm and PETG at 0.5, 0.75, 1, 1.5 and 2 mm.

I order the sheets like this:

and they come in sizes of 1220 mm x 2440 mm (sometimes larger). I use to have to hand cut these down, I get 12 per sheet, which is a pretty boring job, but now I have a large guillotine, which arrived just before Christmas. I've needed one for years, and have finally been about to afford one, and a hydraulic one too  

[yogi-bear 2321]

ok, now onto the vac former. I needed to improve the suction as it was a bit hit and miss. Sealing around the edges was also an issue. The setup used a wet and dry vacuum cleaner in conjunction with a vacuum pump and two vacuum tanks. In the last setup, I'd tried to use solenoids to switch vacuum on and between the vacuum cleaner and tanks, but it was awkward.

Old setup (the vacuum cleaner connects to the white pipe that goes off to the right):

All that gets replaced by an industrial vacuum pump. The new pump has about 10 x the suction and flow than the vacuum cleaner.

 

and the old control panel.

so I remove all the old gear, laser cut a gasket and 

and fitted the new pump directly underneath. Nice and simple and much less restrictive. And now the control panel just has an ON - OFF switch.

top view:

The new pump takes full 240V, so I use a solenoid relay for control.

 

[yogi-bear 2321]

the next part was to get the edges to seal better. A mistake when re-making the sliding rails, was that the frame could no longer touch the base. 

so I built a box with foam top and bottom to help seal. I used a grill to allow for air flow and there is also a crux wipe to prevent and debris entering the vacuum pump.

[yogi-bear 2321]

and now the first test. Using 1 mm ABS, I gotten say, I was really happy   . The pull was very quick and sealed really well. The only issue is that the sides are really too deep, but that's easy to fix. 1 mm is also really too thin for this though, so next time I try the body, I'll go back to1.5 mm ABS. One advantage of the deep sides though, is it 'soaks' up the excess around the edges and should reduce webbing.

and cut out.

 

[matman 1499]

That looks great , Plus it looks like its working well . 

You will be pumping out bodys like nobodys bisness .

Hope the escorts , cortinas are going to get some action  ... 

 

[yogi-bear 2321]

my last test for the day was to try a cockpit that I'd made a resin copy. I used the cheapest fibre glass resin I could find from the auto store. I'm trying resin as its a lot harder than the plaster I've been using. 

Copy and original. If you try this, make sure you use a good release agent, I didn't use enough and nearly destroyed the original. 

 

I tried this in 1 mm ABS also (that's all I'd cut down) which is really too thick for this sort of detail and needs a better plastic for the detail. I'll try 0.5 mm PETG next time.

while I'm happy enough, you can see the loss of details. More vent holes will be needed to help draw out the air in the recesses.

 

[yogi-bear 2321]

7 minutes ago, matman said:

That looks great , Plus it looks like its working well . 

You will be pumping out bodys like nobodys bisness .

Hope the escorts , cortinas are going to get some action  ... 

you bet! Haven't given up yet on the bodies.

[yogi-bear 2321]

ok, small update from the last couple of months.

I still need to copy this Truggy body for @Martell

 

 

This brings us to sometime in late Feb I decided to try some resin casting. My thought was to try and make a resin copy like I did with the cockpit. So I used some thick white cardboard and cut shapes to fill the many gaps. Taped down and then I applied a layer of the rubber plasti-dip so the resin doesn't stick to the shell.

 

I started with an initial pour, with the idea being I rolled the resin around while it dries to do thin coats. However reality had other ideas and the resin reacted with the plastic-dip  so I stopped before I went too far. It affected the paint, but the body was ok.

 

So I thought I'd better test on a body that didn't matter so much. My choice was one of the Escort bodies I vac formed, this one was from PETG.

 

This time I decided to also try fibreglass sheets, that way I use the minimal amount of resin and still have some strength. The inside of the body was coated with a layer of PVA which was allowed to dry and this is to prevent the resin from sticking to the body. I then brushed on resin and then matting, making sure the fibreglass matting always it was wet and pushed into corners, folds etc.

 

So the body didn't fair too well with removal, getting pretty much totally destroyed. Hmm, maybe I need to do more coats with the PVA 

 

but the resin copy was pretty good. I do intend on cleaning this up one day and painting it. I'll cut out the windows (and do the front half).

 

But that process turned me off trying that any further on the Truggy, as there was a good chance it will not survive the process.

I wonder if this is how TGB copy bodies?

 

 

 

 

[yogi-bear 2321]

Fast forward to April and I get a job to vac form a light up exit sign. This was an excellent opportunity to try a 3D printed mold and vac form from that. It wasn't very big, so I was able to do some cockpits at the same time.

I used PLA for printing the mold, but I know it won't last too long, PLAs melting point is too low. In my initial attempt I coated it with acrylic lacquer, which was a mistake as it melted once vac formed and became a bit of mess. The second attempt I used car spray putty and that worked a treat. I also mounted it to wooden based and then gave it a couple of coats of a casting release agent.

 

The cockpit was also mounted to a base and coated. This ended up making the release from the vac formed shape a lot easier.

 

vac formed in 1 mm HIPS

EXIT sign cut out and back lit test. I ended up being able to make 3 of these and by then there was a noticeable bow in the mold for the exit sign. I'll eventually try ABS, that will hold up much better.

 

The 1 mm HIPS was probably a little too thick for the cockpit, with some webbing forming near the seat, but its still quite useable.