its_virgil
Member
Many of yuou have been asking and seem to be interested in the PR casting that I have been doning. Three of us, Serge, Jay Pickens and I, have been experimenting with casting PR in pressurized paint pots. So, here are some of the things these "3 Amigos" have discovered...or sorry Serge, the "Three Mates"
(1) I am down to casting at 40 psi and I think Jay has dropped the pressure down to 30 psi
(2) I have done both clear casting of snake skins and colored castings and as I turn these pieces of PR I have not encountered any bubbles or voids inside the blanks. That is one of the sweetest things I like about the pressure casting. I hated turning a piece of nice colored resin or a snake skin and get almost finished and turn into a bubble. Some can be repaired and some can't. NO MORE BUBBLES!
(3) I have made some shelves to go inside the post to better utilize the space so multiple molds can be cast at once. I also have a top shelf, close to the top of the pot and nothing is on this shelp, but it is used to deflect the air so air rushing in does not disturb the resin, especially in the multi colored casting. Don't know if it is needed, but I use it. I can just visualize a 1/4 inch stream of air at 120 psi blowing a mold full of PR all over the inside of the pot and contaminating the other molds.
(4) As soon as the PR has jelled, the pressure can be released and another casting caan be made. Once it has set the bubbles are trapped in their small state for all of eternity
(5) On clear casting, as in the snake skins, the PR is coming out crystal clear. It was clear prior to pressure casting, but I really think the pressure casting has made it even more clear. Any amount of air in the mix causes some reduction in clearness(or so it would seem to me...I am no chemist nor physicist), but the pressure is eleminating the air and the skins show up better than ever.
(6) Making the first cast using Jay's method of supporting the skinned tubes proved a disaster. Not only does the pressure squeeze the air bubbles to an invisible state, but it also pushed the resin into the tubes between the dowel and the tube. Having metal weights in the tubes to keep them from floating and having the tubes fill with resing...well it was a disaster...But my solution was to use corks...regular corks...Pushed into the tube ends as far as I could...one drop of CA on the corks exposed end and stick a 3/4" square disk to the cork to hold it off the mold bottom. (Read Jay's article on the home page and you will know what I'm talking about) Not a drop of resin in the tubes. The first two casts were done with slimlines. Then I did some barons, gents, sierras and the results were not as successful. The gents filled completely. Maybe I didn't push the corks in far and tight enougng...One baron tube filled and one sierra tube filled. I think the problem was the cork not pushed in far enough. Another cast is coming and I'll have more info on this later. It will get solved.
(7) Cork sizes I've used so far have been #00, #0, #1, #2, #3, and #4. I didn't know corks came in sizes either. The first ones I bought came from Lowes at 34 cents each. I just purchased corks from
http://www.sunburstbottle.com/s.nl/sc.13/category.39/.f and they were 6 to 9 cents each. The corks are not reuseable.
This seem to answer the questions that have been asked of me so far. If I think of any more bits of info I will add to this list. A comprehensive article is in the works on PR casting and snake skin casting. Look for it soon and news-stands nearest you!
Do a good turn daily!
Don
(1) I am down to casting at 40 psi and I think Jay has dropped the pressure down to 30 psi
(2) I have done both clear casting of snake skins and colored castings and as I turn these pieces of PR I have not encountered any bubbles or voids inside the blanks. That is one of the sweetest things I like about the pressure casting. I hated turning a piece of nice colored resin or a snake skin and get almost finished and turn into a bubble. Some can be repaired and some can't. NO MORE BUBBLES!
(3) I have made some shelves to go inside the post to better utilize the space so multiple molds can be cast at once. I also have a top shelf, close to the top of the pot and nothing is on this shelp, but it is used to deflect the air so air rushing in does not disturb the resin, especially in the multi colored casting. Don't know if it is needed, but I use it. I can just visualize a 1/4 inch stream of air at 120 psi blowing a mold full of PR all over the inside of the pot and contaminating the other molds.
(4) As soon as the PR has jelled, the pressure can be released and another casting caan be made. Once it has set the bubbles are trapped in their small state for all of eternity
(5) On clear casting, as in the snake skins, the PR is coming out crystal clear. It was clear prior to pressure casting, but I really think the pressure casting has made it even more clear. Any amount of air in the mix causes some reduction in clearness(or so it would seem to me...I am no chemist nor physicist), but the pressure is eleminating the air and the skins show up better than ever.
(6) Making the first cast using Jay's method of supporting the skinned tubes proved a disaster. Not only does the pressure squeeze the air bubbles to an invisible state, but it also pushed the resin into the tubes between the dowel and the tube. Having metal weights in the tubes to keep them from floating and having the tubes fill with resing...well it was a disaster...But my solution was to use corks...regular corks...Pushed into the tube ends as far as I could...one drop of CA on the corks exposed end and stick a 3/4" square disk to the cork to hold it off the mold bottom. (Read Jay's article on the home page and you will know what I'm talking about) Not a drop of resin in the tubes. The first two casts were done with slimlines. Then I did some barons, gents, sierras and the results were not as successful. The gents filled completely. Maybe I didn't push the corks in far and tight enougng...One baron tube filled and one sierra tube filled. I think the problem was the cork not pushed in far enough. Another cast is coming and I'll have more info on this later. It will get solved.
(7) Cork sizes I've used so far have been #00, #0, #1, #2, #3, and #4. I didn't know corks came in sizes either. The first ones I bought came from Lowes at 34 cents each. I just purchased corks from
http://www.sunburstbottle.com/s.nl/sc.13/category.39/.f and they were 6 to 9 cents each. The corks are not reuseable.
This seem to answer the questions that have been asked of me so far. If I think of any more bits of info I will add to this list. A comprehensive article is in the works on PR casting and snake skin casting. Look for it soon and news-stands nearest you!
Do a good turn daily!
Don