Air bubbles

[jttheclockman]

Tried my first casting today and want to use the method to make bottlestoppers with embedded items. Noticed when I poured the top layer there are tiny bubbles in the pour. The item embedded was a solid item ( penny) so don't think there was gases from it. Now is there any secrets that can be followed without the use of a pressure pot??? When mixing I tried not to agitate too much. Poured slowly. Maybe using less harder or some other trick to slow curing to let bubbles escape. Just thinking out loud. Thanks for the replys.

 

[toolcrazy]

You can use a jewlery cleaner to degas the PR before pouring. Or use a pressure pot, even this don't get rid of all the bubbles.

 

[jttheclockman]

"JEWLERY CLEANER" More info needed on that one please.

 

[OKLAHOMAN]

Another thing you can do is before adding the hardner let the resin just sit for an hr or so if you dont have a pressure pot. You will see the bubbles rise to the top as it sits.

 

[its_virgil]

I must say that using the ultrasonic jewelery cleaner or vacuum to degas the resin then casting with 30 psi in my pressure pot had eliminated all visible bubbles...there may still be some but I can't see them. I've had no complaints from others who have turned my snake skin blanks...about bubbles or any thing else. The ultrasonic cleaner is producing excellent results for me (and others) and using it is soooooo much easier than the vacuum pump.
Do a good turn daily!
Don

Originally posted by toolcrazy
<br />You can use a jewlery cleaner to degas the PR before pouring. Or use a pressure pot, even this don't get rid of all the bubbles.

 

[toolcrazy]

http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=3305

Try this as an example. It vibrates the bubbles out of the PR. Or you can make your own, there is a post about that just recently.

 

[edstreet]

has anyone tried a centrifuge type setup to remove the air bubbles? In metal casting that's one method how they remove them, was wondering if that would work just as well in the casting here.

Ed

 

[great12b4ever]

I don't do castings but I do fill cutouts with epoxy in a lot of my craft items. I have found that taping the object while the epoxy is fresh and wet to my scroll saw table and turning it on gives me enough vibration to remove ari bubbles. Maybe this will work with castings. Might be worth a try before making or buying a vibrating table.

Rob

 

[gketell]

Ed,

Actually the centrifuge is just for getting the molten metal into the molds. It doesn't necessarily get rid of air bubbles.

GK
Who remelted lots of "bad casts" as a kid working in a jewelry sweat shop.