Vacuum forming sheet metal

Moderator: Mike Everman

Mike Everman
Posts: 4932
Joined: Fri Oct 31, 2003 7:25 am
Antipspambot question: 0
Location: santa barbara, CA
Contact:

Vacuum forming sheet metal

Post by Mike Everman » Sat Feb 28, 2004 5:38 am

Getting ready to hit this with the mini shop vac and a torch, photos pretty self explanitory. I'm using plaster of paris, pam for a mold release, a frying pan to hold the mold, silicone caulk to seal the sheet all around.
I am making a test pull of aluminum sheet, then I'll try some .035" thick steel if it works.
Attachments
ready aluminum test pull.gif
ready aluminum test pull.gif (35.66 KiB) Viewed 9615 times
vac feed groove and fitting clearance.gif
vac feed groove and fitting clearance.gif (30.89 KiB) Viewed 9615 times
test shape, arizona iced tea.gif
test shape, arizona iced tea.gif (35.18 KiB) Viewed 9615 times
Mike
__________________________
Follow my technical science blog at: http://mikeeverman.com/
Get alerts for the above on twitter at: http://twitter.com/mikeeverman

paul skinner
Posts: 427
Joined: Fri Oct 03, 2003 9:59 pm

Post by paul skinner » Sat Feb 28, 2004 9:04 pm

Can't see it happening with a shop vac. I'm not sure you could produce the necessary tors.

Maybe a vaccum pump from an old fridge motor..Might work.

Mike Everman
Posts: 4932
Joined: Fri Oct 31, 2003 7:25 am
Antipspambot question: 0
Location: santa barbara, CA
Contact:

Post by Mike Everman » Sat Feb 28, 2004 9:31 pm

Hey, PS, long time no hear. I have a good vacuum pump, well more vacuum than needed. The shop vac and a propane torch will do it for the aluminum flashing, it goes very floppy under the torch.
I fully expect to use the better vacuum pump and oxy/acetylene on the sheet steel...
Mike
__________________________
Follow my technical science blog at: http://mikeeverman.com/
Get alerts for the above on twitter at: http://twitter.com/mikeeverman

resosys
Posts: 292
Joined: Wed Dec 10, 2003 11:26 pm
Antipspambot question: 0
Location: Sacramento, CA, USA

Post by resosys » Sat Feb 28, 2004 9:39 pm

Mike Everman wrote:Hey, PS, long time no hear. I have a good vacuum pump, well more vacuum than needed. The shop vac and a propane torch will do it for the aluminum flashing, it goes very floppy under the torch.
I fully expect to use the better vacuum pump and oxy/acetylene on the sheet steel...
Mike, did you get the aluminum to form?

You need a webcam in your shop.

Chris

Mike Everman
Posts: 4932
Joined: Fri Oct 31, 2003 7:25 am
Antipspambot question: 0
Location: santa barbara, CA
Contact:

Post by Mike Everman » Sun Feb 29, 2004 2:08 am

Hi, Chris. A web cam would show no progress 23.5 hrs a day! I need to make a frame to clamp down the sheet all around the perifery; warpage killed the vacuum seal almost immediately.
Mike
__________________________
Follow my technical science blog at: http://mikeeverman.com/
Get alerts for the above on twitter at: http://twitter.com/mikeeverman

resosys
Posts: 292
Joined: Wed Dec 10, 2003 11:26 pm
Antipspambot question: 0
Location: Sacramento, CA, USA

Post by resosys » Sun Feb 29, 2004 3:26 am

Mike Everman wrote:Hi, Chris. A web cam would show no progress 23.5 hrs a day! I need to make a frame to clamp down the sheet all around the perifery; warpage killed the vacuum seal almost immediately.
Right, but you couls turn on the webcam when working and we could all crack a beer and marvel at the jar collection!

My vacuum former (home built) uses a frame above the work to keep the seal at the edges. A frame with some weight may work well for holding it down while you heat and suck :->.

Chris

Axt
Posts: 57
Joined: Sat Nov 15, 2003 2:04 pm
Antipspambot question: 0
Location: Australia

Post by Axt » Sun Feb 29, 2004 3:47 am

If you cant create enough vacuum, put it in a water tank and crack an explosive on top of it.. always wanted to try this. Though you would probably want in the least an underground thick cement tank and mould even for thin sheet.

Heres an overview on explosive forming, your halfway there - http://www.metalwebnews.com/howto/explo ... rming.html

Mike Everman
Posts: 4932
Joined: Fri Oct 31, 2003 7:25 am
Antipspambot question: 0
Location: santa barbara, CA
Contact:

Post by Mike Everman » Sun Feb 29, 2004 4:04 am

Speaking of explosive forming, I'm making devices to steer the most powerful lasers in the world for the National Ignition Facility at Lawrence Livermore Labs. One of the coolest things was the target chamber, 10 meters in diameter, spherical, and 100mm thick aluminum. they explosively formed panels soccer-ball style in Germany (very big bangs, I'm thinking) and welded it together here. It also ends up being one of the world's cleanest places, which is kind of important when you dump 50 times the U.S. power grid wattage, in 192 beam lines converging on a spot the size of a pencil eraser, in all of 8 nanoseconds! Fun stuff!

Sure puts burning a little propane in a tube in perspective, but all things considered, I'd rather be making thrust.
Mike
__________________________
Follow my technical science blog at: http://mikeeverman.com/
Get alerts for the above on twitter at: http://twitter.com/mikeeverman

Mark
Posts: 10777
Joined: Sat Oct 11, 2003 10:14 pm

Always wear your goggles with laser beams

Post by Mark » Sun Feb 29, 2004 6:07 am

I remember reading of some experimentation with high energy lasers fired from a large airplane. There were several mirrors and the sudden blast of laser energy bounced off the mirrors and on out to the target. But because there was some dust and airborne particles in that part of the plane, these reflected some of the light and burned interesting/disconcerting tiny holes in some of the strapping and other parts of the plane.
Mark

Mike Everman
Posts: 4932
Joined: Fri Oct 31, 2003 7:25 am
Antipspambot question: 0
Location: santa barbara, CA
Contact:

Post by Mike Everman » Sun Feb 29, 2004 6:19 am

Not the least of the worries with that powerful airborne laser was where the stray light ends up, whether glancing off of a target, or through it, or just a miss. You can have people on the horizon spontaniously combust (OK maybe not combust exactly...), or just seeing the hit or the beam cross a cloud can make most hapless observers blind.
Mike
__________________________
Follow my technical science blog at: http://mikeeverman.com/
Get alerts for the above on twitter at: http://twitter.com/mikeeverman

Rescyou
Posts: 100
Joined: Mon Oct 06, 2003 3:45 am
Antipspambot question: 0
Location: Alberta Canada
Contact:

Really Sux

Post by Rescyou » Mon Mar 01, 2004 2:58 am

I have a 5x10^-7 Torr cryo/turbo molecular pump and some other toys that can suck a Boeing 747 through a garden hose, I might just have to retrofit it a bit and try some vacuum-forming as I was messing with the pumps for some plasma stuff and it didn't even dawn on me for vac forming.

s.
The mind of a man is the man himself.

Rescyou
Posts: 100
Joined: Mon Oct 06, 2003 3:45 am
Antipspambot question: 0
Location: Alberta Canada
Contact:

Sucking the grey off a battleship..

Post by Rescyou » Mon Mar 01, 2004 3:59 am

Whilst looking for some super sucker projects I came across this article for those that are interested in things that suck:

http://www.dream-models.com/h/vacuumpump.html

s.
The mind of a man is the man himself.

Viv
Posts: 2158
Joined: Sat Oct 04, 2003 2:35 pm
Antipspambot question: 125
Location: Normandy, France, Wales, Europe
Contact:

Re: Really Sux

Post by Viv » Mon Mar 01, 2004 10:04 am

Rescyou wrote:I have a 5x10^-7 Torr cryo/turbo molecular pump and some other toys that can suck a Boeing 747 through a garden hose, I might just have to retrofit it a bit and try some vacuum-forming as I was messing with the pumps for some plasma stuff and it didn't even dawn on me for vac forming.

s.
You have a cryo pump and a turbo molecular paump just laying around!

Shit!

I hope you have a good rotary vane pump for the forline for them as well.

Viv
"Sometimes the lies you tell are less frightening than the loneliness you might feel if you stopped telling them" Brock Clarke

Viv's blog

Monsieur le commentaire

Rescyou
Posts: 100
Joined: Mon Oct 06, 2003 3:45 am
Antipspambot question: 0
Location: Alberta Canada
Contact:

One word

Post by Rescyou » Mon Mar 01, 2004 3:48 pm

One word Viv, "EBAY"

I was looking at the molec. pumps because of they have some pretty funky compressor blades and snagged one on eBay for about $50. The guy didn't know what it was and sent it as well as some other misc. pieces, one of which was a cryo pump. So Shane got himself about $15000 worth of goodies for $50 and $100 shipping.

I definitely have a high volume pump to take care of 90% of it.
s.
The mind of a man is the man himself.

Viv
Posts: 2158
Joined: Sat Oct 04, 2003 2:35 pm
Antipspambot question: 125
Location: Normandy, France, Wales, Europe
Contact:

Re: One word

Post by Viv » Mon Mar 01, 2004 3:57 pm

Rescyou wrote:One word Viv, "EBAY"

I was looking at the molec. pumps because of they have some pretty funky compressor blades and snagged one on eBay for about $50. The guy didn't know what it was and sent it as well as some other misc. pieces, one of which was a cryo pump. So Shane got himself about $15000 worth of goodies for $50 and $100 shipping.

I definitely have a high volume pump to take care of 90% of it.
s.
The last vac systems I worked on had two of them at £50k each! very nice 150000rpm on magnetic bearings.

Took a 6' square chamber down to 10-8mt and pretty damn fast too as I recall.

Have you got the healium unit for the cryo pump as well

Viv
"Sometimes the lies you tell are less frightening than the loneliness you might feel if you stopped telling them" Brock Clarke

Viv's blog

Monsieur le commentaire

Post Reply