Vacuum PR before pouring

[chartle]

I've seen some videos where they put the PR in a vacuum pot for a few seconds before pouring to get the bubbles out. I don't have a vacuum pump and don't plan on getting one.

Do you think it would be worth it to use the accessory vacuum hose that's on my seal a meal and a small mason jar rigged up with the hose to give it a few seconds of most likely lighter vacuum to degass it?

I can't leave it running with some sort of chamber because the Seal a meal will only run for a minute or two.

Going to try a clear PR pour and there can not be any bubbles. The blank is going to take me 5 hours of hand work to make.

 

[KenV]

Don Ward - (Its_Virgil) has provided instructions/description on how he does it several times. Don casts lots of clear blanks. He does not use vacuum.

 

[chartle]

Its one of those things I have the seal a meal and the chamber, a marinating dish so I may try it this morning.

can't hurt

 

[longbeard]

Ive casted hundreds of blanks, never used vacuum, dont see a reason too.
I use a pressure pot. Some will set the mold on something that vibrates to eliminate the bubbles.



Harry

 

[tomtedesco]

I try to stir the PR slowly so as not to create bubbles, have not used vacuum and get good results.

 

[its_virgil]

Styrene is a solvent to make polyresin thinner and also helps in the cross linking for strength. The styrene will evaporate from the resin if the vacuum is more than 27 inHg. A gauge is important. When I was using vacuum I kept the vacuum at 25 inHg to prevent the styrene from evaporating. I no long use vacuum and haven't for several years now.
Do a good turn daily!
Don

 

[chartle]

Ok here is a report.

While the resin moved around a bit I didn't see any bubbles popping. So I'll stick with warning my resin on a candle warmer.

I also use it to gently warm the blanks as they cure in a water bath. They get up to around 140 f.

 

[79spitfire]

I can't help but ask, Can we have pictures of the results? Good or bad please share your learning!!
Thanks!

 

[lorbay]

I've seen some videos where they put the PR in a vacuum pot for a few seconds before pouring to get the bubbles out. I don't have a vacuum pump and don't plan on getting one.

Do you think it would be worth it to use the accessory vacuum hose that's on my seal a meal and a small mason jar rigged up with the hose to give it a few seconds of most likely lighter vacuum to degass it?

I can't leave it running with some sort of chamber because the Seal a meal will only run for a minute or two.

Going to try a clear PR pour and there can not be any bubbles. The blank is going to take me 5 hours of hand work to make.

Check out Don's tutorial here.
http://content.penturners.org/library/techniques/casting_bubble_free.pdf
Not sure why he didn't reference it.

Lin

 

[chartle]

I can't help but ask, Can we have pictures of the results? Good or bad please share your learning!!
Thanks!

Here is my setup. But they are still cooking. After an hour in the bath they we're past gummy. But I haven't been home.

 

[chartle]

Done "cooking". There are done with alcohol inks. Epresso and copper mix ins.

I may get to drilling and painting tomorrow if I can get out and get some copper craft paint. And then turn them Tuesday.