Degassing tool

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Harry
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Degassing tool

Post by Harry »

Here is what I set up for degassing tool and making packets to load into it. Also an idea for a tool that might work out well. Will put it together and report back on how it does.
degasser_unloaded.jpg

degasser_wrap.jpg

degasser_wrapped.jpg

degasser_filling.jpg

degasser_filled.jpg

degasser_loaded.jpg
The new tool I will make is a piece of 1/2" pipe about 2" long with about 1/2" cut off the lower end. These two pieces will be welded to to large washers that are tacked together with a very small gap between them. The top of the tool will be blocked/sealed by the tool handle. My thought is the gap should be small enough to keep metal from flowing into it yet big enough the gas will escape. The piece of pipe below will create some small back pressure to force the gas through the small gap.

The hope is that this will do a couple things. Number one is to make lots of small bubbles out of the large bubbles I get from the current tool. Secondly disperse the bubbles over a wider area. The tool above tend to see the bubbles coming up alongside of the handle and doesnt seem to cover much of the melt unless I slowly 'stir it around while the degasser is active.
degasser_idea.jpg
I'd rather laugh with the sinners than cry with the saints the sinners are much more fun...
Muller
blindpig
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Re: Degassing tool

Post by blindpig »

Harry, I like your idea of dispersing the bubbles and will be glad to hear/see your results. The only question I have is will the bottom being open allow the gas bubbles escape from below as there is less resistance than the narrow slits(maybe I'm not seeing your plan correctly).In my case have been stiring quickly to spread gas before it runs out and always wonder if it's working well.
Good luck with your new design.
Don
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Harry
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Re: Degassing tool

Post by Harry »

I just dont think stirring quickly is a good idea Don, seems like agitating the top of the melt would just introduce more gas. I do a very gentle stir once or twice around the pot once the gas starts bubbling.

I am hoping the greater pressure at the bottom of the tool will be enough to overcome the difference in resistance. Might end up putting the washers up higher on the tool to make this even more pronounced but I dont think it will need much. The gas should travel through a very small gap without resistance and even if the volume goes up too high as the reaction peaks the washers will help to disperse any bubbles that do come out of the bottom and force them away from the handle so they dont tend to travel up the handle.
I'd rather laugh with the sinners than cry with the saints the sinners are much more fun...
Muller
dallen
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Re: Degassing tool

Post by dallen »

regular foundry degass tool is an inverted cup or cone with one of them big tables stuck inside it. I use a .5 diameter stainless steel tube welded to a rod, that I put maybe a half teaspoon of chemical into. this new stuff is really active.
David and Charlie aka the shop monster

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blindpig
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Joined: Thu Jun 02, 2011 5:06 pm

Re: Degassing tool

Post by blindpig »

Thanks for the explaination Harry,sounds like it should work well.Can't wait to see your test results.
Don
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