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jegner Site Admin
Joined: 30 May 2003 Posts: 2144 Location: Texas, USA
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Posted: Tue Jun 28, 2005 7:57 am Post subject: ABS vs. HIPs |
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Well I've tested some 1 side glossy 1 side haircell ABS in a .062 thickness. It heats up fine, gets soft no problem. Won't hold detail. Has an issue with the texture side showing up on the glossy side. I also had a high degree of failure with the ABS. Of 6 pulls I made only one was useable. No good. I have a lot better luck with HIPs. My home-made vacuum form machine is not up to the challenge to form ABS. Simple as that. A hi-vac rig with an oven that has temp control might work fine. I like HIPs fine, so thats what I'll be using. The 2 sided glossy ABS is hard to find, most plastic suppliers don't stock it. I'm sticking with HIPs.
Jim |
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knightshade Expert
Joined: 19 Jun 2005 Posts: 123 Location: Rochester NY
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Posted: Wed Jun 29, 2005 3:19 pm Post subject: |
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Thanks for the info!
Guess that I'll need to plan for some trial & error if I ever want to move into the realm of ABS. Guess that it is HIPs for my first plastic order |
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jegner Site Admin
Joined: 30 May 2003 Posts: 2144 Location: Texas, USA
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Posted: Wed Jun 29, 2005 3:22 pm Post subject: |
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HIPs is so much easier to deal with, I was shocked when the ABS did what it did. If I ever get my hi-vac system up and running I'll try ABS again. |
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knightshade Expert
Joined: 19 Jun 2005 Posts: 123 Location: Rochester NY
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Posted: Wed Jun 29, 2005 5:56 pm Post subject: |
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I suspect that the hi-vac system may be needed. I am curious if a 6hp shop-vac would do any better - so sometime after I have molds and some practice with HIPs - I'll play with it. |
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jegner Site Admin
Joined: 30 May 2003 Posts: 2144 Location: Texas, USA
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Posted: Wed Jun 29, 2005 6:01 pm Post subject: |
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I'm running a 3hp AND a 6.5hp shop vac in parallel. No go. |
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knightshade Expert
Joined: 19 Jun 2005 Posts: 123 Location: Rochester NY
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Posted: Wed Jun 29, 2005 8:02 pm Post subject: |
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LOL - I guess that I missed the upgrade
Last I knew you were just running the 3hp |
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jegner Site Admin
Joined: 30 May 2003 Posts: 2144 Location: Texas, USA
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Posted: Thu Jun 30, 2005 1:02 pm Post subject: |
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knightshade wrote: | LOL - I guess that I missed the upgrade
Last I knew you were just running the 3hp |
Try:
http://www.tk560.com/vactable4.html for the updated info. The shop vac just happened this past week! |
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yodasoda Newbie
Joined: 04 Sep 2005 Posts: 10
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Posted: Tue Sep 20, 2005 1:34 pm Post subject: |
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WHere could I get a high vac system, how powerful is one, where can I buy one, and how much does it cost? |
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jegner Site Admin
Joined: 30 May 2003 Posts: 2144 Location: Texas, USA
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Posted: Tue Sep 20, 2005 2:19 pm Post subject: |
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Hi vac refers to a 28in/hg vac pump, plumbing, valves and a storage tank, usually 30 gallons. The pumps for these systems will run $400 and up for a 6CFM or faster setup. You need 5+ CFM to evacuate the tank faster than the oven heats the plastic, otherwise you have a problem. The hi-vac setup really complicates the vac-form machine, adding a lot of additional expense to the rig without really helping that much. The payoff is, tighter faster pulls. And an ability to pull thicker material. I've been running my vac-form machine for almost a year and a half, and I'm just getting around to adding a Hi-Vac setup. |
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crashmann Guru
Joined: 27 Sep 2005 Posts: 501
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Posted: Mon Oct 03, 2005 8:24 pm Post subject: |
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I was fortunate to win a Gast 1065 pump and motor from everyone's favorite auction site, but looking at the plumbing and vacuum storage tank... That would make the vac table a stationary rig. Currently, I move it outside and up a flight of stairs, (rather than work in the basement with the fumes going through the house) The pump and motor are almost 70 pounds!!! Maybe I could just run a length of tubing from the tank to the platen, and leave the pump inside the house, hmm...
The 6.5HP shop vac has been doing a great job pulling .090 HIPS, and although some of the details are a little soft, I am very happy with its performance on the .125 HIPS.
I also got disappointing results with haircell/smooth ABS. I got a lot of orange peel finish where the plastic pulled thin, and the details were very soft. I heard there's a "drying" procedure for ABS where you heat it at 200 degrees for 4 hours - yeah, right... This is supposed to work the moisture out of the plastic, preventing pitting. I'm gonna stick with HIPS for now.
I'll be saving my pennies to build the garage for the permanent setup, THEN I can hook up the hi vac pump!
Charlie
Last edited by crashmann on Tue Mar 28, 2006 10:41 pm; edited 1 time in total |
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jegner Site Admin
Joined: 30 May 2003 Posts: 2144 Location: Texas, USA
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Posted: Mon Oct 03, 2005 8:34 pm Post subject: |
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I too have been happy with the shop vac powered vac-machine. I've pulled .093 HIPs with no trouble, and even a sheet of .125 storm door acrylic with that rig. The high vac system will make pulling negative molds, something I won't even attempt with my current rig, an option. I have a Viper Pilot helmet I'd love to do as a negative mold.
Yes, ABS does require a dry cycle and to get decent trooper armor pulls with that stuff, you need custom made smooth/smooth sided ABS, as the haircell adds to the poor quality pulls.
HIPS works great for me, and I'm happy with the end results. ABS is about 60% waste for me. Thats not good.
Jim |
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TK161 Newbie
Joined: 09 Mar 2006 Posts: 18
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Posted: Thu Mar 09, 2006 2:11 pm Post subject: |
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I also had problems with the orange peel with the abs. I found out that you need to heat the abs a lot longer. It needs at least a 6" droop. I rebuilt my oven walls to be 7.5" high to allow for the additional droop. I heated the abs with the 6" droop, formed it and the orange peel was gone. Nice shiny surface. It didn't pull any tighter though. |
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ANH trooper Master
Joined: 20 Oct 2005 Posts: 305 Location: UK
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Posted: Thu Mar 09, 2006 4:31 pm Post subject: |
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So was it haircell ABS or smooth that you used?
I can let the plastic sag about 10" if need be.Do you reckon it pulled as well as HIPS or worse?Have you been getting very good results with your HIPS or average?
I'm gonna have to try it for myself.I know you don't need a high vac for HIPS to get very good results,but ABS seems more tricky! |
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TK161 Newbie
Joined: 09 Mar 2006 Posts: 18
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Posted: Fri Mar 10, 2006 7:15 am Post subject: |
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I used the 2 side smooth lately. I did use the one side hair cell and I got the same result with the orange peal. I haven't tried the hair cell with a 6" sag though so I'm not sure if that fixes that problem. I know it worked for the 2 sided smooth though. It also fixed the thin areas and made the thickness a bit more uniform. I haven't pulled any hips yet. I'm still knew to vacuforming. I have some hips on its way. I'm using a dome mold for a snowtrooper helmet with a ridge around the bottom. The abs didn't pull into the corners of the ridge. It doesn't look bad but It's not as tight as I would like. But the 6" sag did fix the orange peal problem and thin areas. I haven't tried a sag larger than 6". I wonder if it would pull better with a larger sag. I'd like to hear if it works for you or not. Keep us posted. |
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ANH trooper Master
Joined: 20 Oct 2005 Posts: 305 Location: UK
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Posted: Fri Mar 10, 2006 11:04 am Post subject: |
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Well as a rule,I let the plastic sag at least the size of the mould I am forming.I also make sure the plastic is very hot too.You need to vent your moulds if you want to get the plastic to suck into any indents or crevices.I've also found that one big hole in the middle of the forming table is better than hundreds of little holes.The plastic tries to get underneath your mould resulting in a much tighter pull,no need for risers |
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