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TeeCee Newbie
Joined: 15 Jun 2007 Posts: 10
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Posted: Fri Jun 22, 2007 1:50 pm Post subject: My Vac Former... |
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Jim asked if I would post some photo's of my vac former in the introduction thread, so here they are. It's by no means a professionally built rig, in fact, it's quite the opposite.
It was really just an experiment to test out the over design so was banged together in a weekend. It runs on 2 vac sources, I use a shop vac for the initial pull down - all my moulds are hollow - and then close the valve to the vac, before opening the valve for the vac tanks to 'finish it off'.
The obligatory oven shot
I am working on another former, this time a little larger to accomidate my larger moulds. It's going to be a 32 x 24 former based on the Doug Walsh design. I didn't want to buy the plans so I just borrowed some ideas from the photo's I've seen. I've just finished wiring up the oven today - but not fitted it yet..
And here's a pic of the 'inside' of the unfinished table.
The tap on the left is for the shop vac - it goes underneath the table on the far left and then joins onto the central part which will plug into the plattern. The tap on the right will go to the 24 gallon tank allowing me to close the valve to the shop vac after the initial pull down and tighten it all up with the tanks.
I opted for a dual valve system rather than the check valve system I've seen described mostly because I couldn't find anything in the UK I could use as the check valve and I was worried that if I had to build a check valve it probably wouldn't work anyway
Comments or suggestions welcomed. |
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jegner Site Admin
Joined: 30 May 2003 Posts: 2144 Location: Texas, USA
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Posted: Fri Jun 22, 2007 2:04 pm Post subject: |
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Very cool! Thanks for sharing!
Is that a clone armor chest plate I see?
Jim |
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TeeCee Newbie
Joined: 15 Jun 2007 Posts: 10
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Posted: Fri Jun 22, 2007 2:38 pm Post subject: |
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It is a clone armour chest
I've been working on the molds for what feels like forever, I'm eventually getting round to pulling myself a suit now. |
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vacman Newbie
Joined: 04 May 2007 Posts: 13
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Posted: Sun Jun 24, 2007 8:04 pm Post subject: |
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Looks very cool. How much did the whole thing cost you and what part did you find the most difficult to construct? |
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TeeCee Newbie
Joined: 15 Jun 2007 Posts: 10
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Posted: Tue Jun 26, 2007 4:22 am Post subject: |
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Thanks.
Unfortunately, I don't think items in the UK are as cheap or as easily available as they are in the U.S. When I first started building I read how a lot of guys over the pond had built one for a few hundred bucks. Then I started to order all the parts and the costs just kept growing.
Altogether the former cost me about £1,000 in parts - I had to ship some materials over from the U.S because you can't buy them in the U.K (v. expensive since they won't ship by any other method than 2 day airmail and there's the import tax too) and getting hold of something to use as a vac tank is near impossible to do on the cheap over here.
As for the hardest part, I thought it would be the oven. Since all the calculations on here were for 110v and no one has built a 240v (I don't think? I couldn't find any reference to someone building one on here), I had to calculate it myself and wasn't sure if it would work at all.
But it turns out the oven was the easy bit and the hardest was building the holding frame for the plastic! I didn't want to use steel box section as I was concerned about the weight with having to constantly lift steel section up to the oven. - I didn't like the idea of a flip flop machine because IMVHO on an over/under as the plastic warms it moves away from heat allowing to to get cooler while the parts that really need the heat stay close to the oven -
I ended up buying aluminium U channels, cutting 45 degree angles, bolting corner plates onto it and then trying to figure out how to make it slide up and down without sticking and how to hold the plastic into the frame. |
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takevin Newbie
Joined: 05 Apr 2006 Posts: 10
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Posted: Sat Nov 17, 2007 5:58 am Post subject: |
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anyone know the type of parts TeeCee used for lifting the frame, custom made or found for the tubes? |
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TK 109 Guru
Joined: 11 May 2007 Posts: 712 Location: Galena, Ohio
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Posted: Sat Nov 17, 2007 10:25 am Post subject: |
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dude, NICE!
what are the coils, nichrome, or something else? if it were nichrome, you outght to stretch them out MUCH more. or if it something else....
just curious! _________________ -Alex
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Fredo Master
Joined: 21 Mar 2007 Posts: 251 Location: Kingdom of Nye Area 51
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Posted: Sat Nov 17, 2007 6:17 pm Post subject: |
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From the looks of the oven it has what looks like about the right amount of wire for a 240 volt oven. Remember it takes about 4 times the wire for 240 volt than it does for a 110 oven......Fredo |
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TeeCee Newbie
Joined: 15 Jun 2007 Posts: 10
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Posted: Thu Nov 22, 2007 3:44 am Post subject: |
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TK 109 wrote: | dude, NICE!
what are the coils, nichrome, or something else? if it were nichrome, you outght to stretch them out MUCH more. or if it something else....
just curious! |
I used Nichrome wire, like Fredo said, with 240 Volts they can't be stretched as much as 110V. I worked it so the oven produces around 3,200 watts and according to my temperature gauge, it reaches around 300 degrees.
I seem to be the reverse of some of the members here when it comes to the plastic - it heats ABS absolutely fine but I tend to get little potmarks (orangepeel?) in the HIPS when I heat it up to the right stage for pulling. Not sure if it's a result of burning the plastic. |
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ANH trooper Master
Joined: 20 Oct 2005 Posts: 305 Location: UK
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Posted: Thu Nov 22, 2007 2:37 pm Post subject: |
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Nice set up Tee Cee!
I might have to pick your brains about the oven mate. I'm wanting to make one like yours with the over head heater so if you get the time, could you fill me in on the details please?
Could you have used gas bottles for the storage tanks? Thanks what I am thinking of using. Should be cheap too |
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TK 109 Guru
Joined: 11 May 2007 Posts: 712 Location: Galena, Ohio
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Posted: Thu Nov 22, 2007 9:02 pm Post subject: |
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OH, ok, thank fredo for clearing that up.
nice work! _________________ -Alex
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TeeCee Newbie
Joined: 15 Jun 2007 Posts: 10
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Posted: Fri Nov 23, 2007 3:34 am Post subject: |
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ANH trooper wrote: |
I might have to pick your brains about the oven mate. I'm wanting to make one like yours with the over head heater so if you get the time, could you fill me in on the details please?
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Of course, what do you need to know?
ANH trooper wrote: |
Could you have used gas bottles for the storage tanks? Thanks what I am thinking of using. Should be cheap too |
I considered propane tanks but the size of tank I wanted just wasn't commercially available, the tanks remain the property of the company - they only sell you the gas and won't sell the bottles unless they're really small and I didn't want the hassle of connecting a load together to make a larger tank.
Since water tanks were too expensive, I started looking at LPG tanks. A 50 litre one goes for around £50 or £60 on eBay and I thought they would be perfect for the job. I purchased one and had to meet the seller on a pub car park to collect so took the opportunity to ask if he had any larger tanks going cheap - just so happens he had 4 x 100 litre propane tanks than he wanted to 'shift quickly'. I bought them and burned off the remaining gas with a roofing torch.
The next problem was trying to get hold of just the POL connection to allow me to connect the vac pump to the tanks valve. They don't just sell the POL connectors without a gas regulator and when I tried to describe why I wanted just a POL connection I was given lectures on safety by every company I phoned.
I ended up just purchasing a standard gas regulator valve from toolstation, cut off the valve so I just had the POL connection, connected that to the tank and then connected a tube to the POL.
It stunk of gas on the first 3 or 4 evacuations (which I did without the heater being on) but after that it works an absolute treat
You can see the one of the huge tanks in the background on the first pic. |
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ANH trooper Master
Joined: 20 Oct 2005 Posts: 305 Location: UK
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Posted: Fri Nov 23, 2007 12:48 pm Post subject: |
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I am planning on using old gas bottles. It would be nice if you could show me how you connected the bottles to the pump and also go into detail about your oven. It looks like you made an oven much the same as everyone else but I would like to know what length coils and how much you stretched them etc. Also the wiring. This is where I get confused with all these calculations and conversions. Seeing how you have done all the hard work, I would be very grateful if you could tell what you did and how you did it. Pictures along the way would be awesome
Cheer mate! |
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drcrash Guru
Joined: 04 Sep 2006 Posts: 705 Location: Austin, Texas
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Posted: Sat Nov 24, 2007 12:53 am Post subject: |
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ANH trooper wrote: | It looks like you made an oven much the same as everyone else but I would like to know what length coils and how much you stretched them etc. Also the wiring. This is where I get confused with all these calculations and conversions. Seeing how you have done all the hard work, I would be very grateful if you could tell what you did and how you did it. Pictures along the way would be awesome
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One thing to be aware of is that a 220 V oven can be built almost exactly the same as a 110V oven, just with half as many segments twice as long. You can use the same amount of nichrome, stretched the same amount. If you look at the 4 configurations that the oven calculator starts up with, check the first and the fourth one---they are essentially identical except that for one, the nichrome layout is divided into four segments, and for the other, it's only divided into two.
If you type the numbers for the fourth column into the first column (changing the volts to 220 and the segments to 2), it will generate the layout at the bottom, which will not change except that two of the segment divisions will disappear.
(If you do it that way not only will the oven consume the same amount of electricity and put out the same amount of heat, the coils will run at the same temperature and generate the same distribution of IR frequencies.) _________________ Paul (a.k.a. Dr. Crash)
Tired of buying cheap plastic crap? Now you can make your own! www.VacuumFormerPlans.com |
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