Keeping "Floaters" down

[Texatdurango]

Hi all,

At our local IAP chapter meeting yesterday we had a casting demo which renewed my interest in casting my own blanks. I just got some alumilite and have dabbled a little so far and one problem I am having is stuff floating to the top during curing.

I noticed Darley just posted some coffee bean blanks in the SYOP forum and he had what I expect to have, the beans oveflowed the blank.

Is this something we just have to deal with or is there a way to keep the beans or whatever from rising outside the intended blank area?

I thought about placing a block on top of the resin but am afraid of trapping air bubbles under the block.

Does anyone have any tips they would like to share? I'm not making these to sell, just for my own use so if you have any secrets you don't want publicly known, send me a PM.

Thanks

 

[Glass Scratcher]

Perhaps you should have titled your thread as "Hey Curtis! I'm using Alumilite and need advice!"

Oh I am in soooo much trouble now... :biggrin:

 

[SherryD]

yes he is going to be in so much trouble.

 

[JayDevin]

when I cast beans in Alumilite, I just plan on floaters...so I make the blank larger than it need to be, pack the beans in as tight as possible and then place another mold on the top. You are not trapping that much air and what irregularities that you have will be turned off anyway.if you use a pressure pot make SURE that in intake valve is not directed at the beans or you will have a pretty bean free form. Since it sets quick you can also just keep pushing them down with a wooden stick that can also just be turned off.

 

[woodman928]

I usually just flush twice :biggrin::biggrin::biggrin::biggrin::biggrin:
Jay

 

[ldb2000]

I place a piece of corian with a coating of vasaline on top of the mold when I tried casting beans . It worked well and all of the beans stayed in the mold . I was using PR under 40 psi and only had a couple of small bubbles to fill with CA .

 

[sbell111]

I place a piece of UHMW on top of the mold and put a weight on it. It will keep the beens from floating out and can be easily knocked off the top when my PR is set up.

You don't have to worry about the bubbles because you are not making an air-tight seal between the UHMW and the mold. Therefore, the pressure will still be the same inside the mold so the bubbles will still float out or shrink down (depending if you are talking about vacuum or pressure).