Building a vacuum table.

[Davor]

And I thought that appearing of Jesus on a toast was the far reach of it ...

[Jerry]

And now, for your viewing pleasure and entertainment.. What happens when vacuum forming goes really really bad.

There has to be a story with that one.

Jerry

[kt315]

Turkish technology looks more progressive. your comments?

[satdaveuk]

Its a good idea saves making a form

[dfbowers]

He's got it down. Looks like he is using a bit thinner plastic. My next step is to get away from using a kitchen oven but what to use for heater elements?
I'm guessing 2000 watts from some other homebuilt ovens I have seen online.

[Jerry]

Turkish technology looks more progressive. your comments?

Very clever use of household tools and a minimum of fabrication. Most of my solutions are much more complicated

Thanks for posting this.

Jerry

[Jerry]

He's got it down. Looks like he is using a bit thinner plastic. My next step is to get away from using a kitchen oven but what to use for heater elements?
I'm guessing 2000 watts from some other homebuilt ovens I have seen online.

I was using a pizza oven which is just too small for more than an 8 inch coil. I was about ready to salvage the heating elements for building a larger one but was saved the trouble by getting an electric kitchen range free to the taking. I have it on castors and just roll it to wherever I want it.

The plastic he was using in the video looks like what is available here for shower surrounds. I measured a piece and it is .047" thick. He was making a coil cover but not sure if that is heavy enough for a coil shell or not.

Jerry

[satdaveuk]

I was using a pizza oven which is just too small for more than an 8 inch coil. I was about ready to salvage the heating elements for building a larger one but was saved the trouble by getting an electric kitchen range free to the taking. I have it on castors and just roll it to wherever I want it.

The plastic he was using in the video looks like what is available here for shower surrounds. I measured a piece and it is .047" thick. He was making a coil cover but not sure if that is heavy enough for a coil shell or not.

Jerry

Pizza ovens don't come cheap either, been looking for ages, the old oven with wheels that you suggested is the way to go its just ive not got the storage that used to have, at one time had a garage compressor with all the tools for spraying etc and loads of industrial bench kit , had to get rid of it all when I sold the land, and far as using the house cooker the Mrs would castrate me even with just a hint of using it

[satdaveuk]

I got to come clean with you lot but just don't tell the Mrs ok
Once last year when Don first showed us his molding project I built one the same out of laminate, the unit it self was fine. When the her indoors was out, I decided to try it out, the plastic I used was a local council flat dustbin lid, anyway had it in the oven for ages and it didn't do the normal sag it just curled up around the edges and started smoking, the smell was intoxicating and stings the eyes spent the rest of the day getting rid of the stink out the house.
Since I was told those lids are produced by injection molding a different make up of type plastics/styrenes that we use.
So thats another lesson for me what not to use

[dfbowers]

I got to come clean with you lot but just don't tell the Mrs ok
Once last year when Don first showed us his molding project I built one the same out of laminate, the unit it self was fine. When the her indoors was out, I decided to try it out, the plastic I used was a local council flat dustbin lid, anyway had it in the oven for ages and it didn't do the normal sag it just curled up around the edges and started smoking, the smell was intoxicating and stings the eyes spent the rest of the day getting rid of the stink out the house.
Since I was told those lids are produced by injection molding a different make up of type plastics/styrenes that we use.
So thats another lesson for me what not to use

That's a good one Dave. We all have plenty of "failure" stories to share. My first vacuum experience was with a plastic sign that I picked up at a hardware store. While the first few tries resulted in duds, it was the right material and eventually worked! It didn't look quite right with the "no parking" lettering on the outside and the material was a little thin.

[satdaveuk]

That's a good one Dave. We all have plenty of "failure" stories to share. My first vacuum experience was with a plastic sign that I picked up at a hardware store. While the first few tries resulted in duds, it was the right material and eventually worked! It didn't look quite right with the "no parking" lettering on the outside and the material was a little thin.

That was a good result because now your making really nice inclosure's so all worth the time and effort, practice makes perfection or at least for most of us lol

[dfbowers]

I need to take the next step in vacuum forming. Two stage! I have been contemplating this for some time now. While I can make endless variations of shells, and sometimes some nearly flawless ones, my yield is not all that great due to poor temperature control and incomplete pull downs. My goal is to make these efficiently enough to be able to help supply these to other Geotech hobbyist (Sven keeps me busy sometimes). My general idea is not original, but I am looking for details on vacuum tanks. Particularly, tank and plumbing size as well as where to find a cheap vacuum pump.

The general idea is to use a shop vac for the initial evacuation and to hold a 1/16" thick sheet of ABS to the platen and when it's still hot engage a second stage to make a complete draw. As it is, I always have a 1/4" or so near the bottom of my forms that never draws down tight to the platen. Any suggestions appreciated.

Don

[SVEN1]

Don,

Years ago I was going to build a vac table for forming radio control boats. Got as far as getting a $1000 vac pump from an air conditioning service man when living in Georgia, cheap $60.00.
his boss bought him a brand new one.......Ended up selling it along with other nifty tools before moving.

You might want to take a look at the vac pumps at Harbor Freight http://www.harborfreight.com/catalog...?q=vacuum+pump
They may even have a retail store near you.

[dfbowers]

Thanks Sven! I have a Harbor Freight 3 miles away.. I have to go check it out tomorrow.
Don..

[Tinkerer]

You can also make a vacuum pump with any old water pump and a ventury valve. Or with a small air compressor and a ventury. They sell kits.