Yes, but he does this commercially in his Plexiglass shop while forming 
full thickness plexiglass.  For people like us, much smaller tanks can 
be used. 
David

Shawn Wilton wrote:

> 8x2.  You mean one of those massive propane tanks people in the 
> country usually have?
>
>
> David P Harris wrote:
>
>> Shawn-
>> 28 mmHg  with a 8x2'  propane tank --- the initial rush is to make 
>> sure a good seal happens. He said for smaller parts with polystyrene, 
>> you can use a old barbeque propane tank with a new valve on it and 
>> attached to a air compressor.
>> No pictures, but essentially a flat square board with lots of holes, 
>> a frame around it, and a chamber below attached to your vacuum.  Set 
>> the plastic on top and then heat with a heat gun or hair dryer until 
>> sagging, then let 'er rip.
>> David
>>
>>
>>
>> Shawn Wilton wrote:
>>
>>> David, can you get some pictures from your buddy, perhaps a few more 
>>> details.  What sort of vacuum are we looking at?  100's of PSI's, or 
>>> what?
>>>
>>> -Shawn
>>>
>>> David P Harris wrote:
>>>
>>>> My friend does plexiglass forming.  Wooden frame, kitchen oven 
>>>> element for heater.  Large air-tanks connected to a pump.  These 
>>>> are pumped out, then a valve opens and the vacuum forming happens 
>>>> very quickly. David
>>>>
>>>> Roland wrote:
>>>>
>>>>>> BTW, the hard parts of vacuum forming seem to be the matter of an 
>>>>>> oven big
>>>>>> enough for the work and creating a vacuum source (or is it sink?) 
>>>>>> with
>>>>>> enough volume to draw down the material before the material cools 
>>>>>> out of the
>>>>>> plastic condition...
>>>>>>   
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>
>>>>> Hi
>>>>> I've watched vacuum forming done, and it was a very simple set-up. 
>>>>> They
>>>>> were forming polystyrene(not foam!)
>>>>> The positive/pattern was simple wood fabrications, and there was 
>>>>> no oven,
>>>>> rather a big element and a few fans blowing the air down. I think the
>>>>> vacuum part was just an industrial blower, as a sucker.
>>>>>
>>>>> The force required will depend on the temperature, depth of draw 
>>>>> required,
>>>>> thickness of sheet, resolution of pattern. Although a nice convoluted
>>>>> surface can be obtained, the edges always pose a problem, same with
>>>>> fibreglass moulds. Trimming them to an exact size, and polishing 
>>>>> to hide
>>>>> the work, is almost impossible.
>>>>>
>>>>>
>>>>>  
>>>>>
>>>>>> A home vacuum cleaner arrangement is not really up to the task. 
>>>>>> Besides, my
>>>>>> earlier experiments with home vacuums lead me to believe a lot of 
>>>>>> air FLOW
>>>>>> is essential to avoid toasting the motors.
>>>>>>   
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>
>>>>> maybe a powerful blower and a venturi will be better??
>>>>>
>>>>> Regards
>>>>> Roland Jollivet
>>>>>
>>>>> _______________________________________________
>>>>> http://www.piclist.com
>>>>> View/change your membership options at
>>>>> http://mailman.mit.edu/mailman/listinfo/piclist
>>>>>
>>>>>  
>>>>>
>>>>
>>>>
>>>>
>>>> _______________________________________________
>>>> http://www.piclist.com
>>>> View/change your membership options at
>>>> http://mailman.mit.edu/mailman/listinfo/piclist
>>>
>>>
>>>
>>> _______________________________________________
>>> http://www.piclist.com
>>> View/change your membership options at
>>> http://mailman.mit.edu/mailman/listinfo/piclist
>>>
>>
>>
>>
>> _______________________________________________
>> http://www.piclist.com
>> View/change your membership options at
>> http://mailman.mit.edu/mailman/listinfo/piclist
>
> _______________________________________________
> http://www.piclist.com
> View/change your membership options at
> http://mailman.mit.edu/mailman/listinfo/piclist
>



_______________________________________________
http://www.piclist.com
View/change your membership options at
http://mailman.mit.edu/mailman/listinfo/piclist