Several years ago I bought a mold and resin kit, one of each. The Resin kit came with two large bottles, 'A' and 'B' mixtures, to be mixed in equal parts. The resin has sat in a cupboard for several years now since I last used it. The clear (A) seems nice and fluid and normal looking, however the (B) seems a little thick. I've tried 3 or 4 mixes now, with each mix foamng to about a 3/8's or more larger than the mold. Very foamy. I don't believe there is any moisture in the containers I used for mixing. Everything I've read points to moisture but my mixing containers are dry. It's winter and even the air is dry now.
Here's what I've been doing:
I shook the (B) before using and brought it to room temperature. Mixed equal parts and stirred until uniform color. (Tan) and then poured half into mold and left part of the mixture in the mixing cup. Every attempt has resulted in severe foaming in the mold and mixing cup. I've repeated this process 3 times now with the same results.
I'm caught in a bind. If I reorder will the reordered resin do the same thing. Is there a shelf life on this resin? I have so much resin left that it would be such a shame to toss it . Would really like to find a way to use what I have rather than take a chance on ordering more.
Thanks for replying. It is encouraging to know that there probably is no shelf life on the Resin mixtures. Looking to your links, perhaps my mix ratios are off. Don't have the young eyes anymore. I will dig out my kitchen scale and try the 14g method. I also did not shake or stir the 'A' mixture so will be sure to do that as well. It seems that my castings are more ovrsize than foamy, almost twice the size of the knob mold. Most of the cast looks quite good and I may be able to use the knob if I saw off the excess on the bottom. I'd include a picture but I dont see a place to do so.
Thanks for your reply. Will let you know how I make out.
........... I'd include a picture but I dont see a place to do so.....
All the best, Ed
I use FOTKI....for each picture in my acct. there is an option in SHARE that allows me to post pictures.... "Code for forums"... I double click on that and post the link in the response....just like this response here.
Well, I was unsuccessful. I shook each mixture ..poured out exactly 7g in each cup...stirred both .. then poured the A into the B and stirred until no visible swirls..about 30 seconds or so. Then poured into a mold. Again the molded item burst out of the mold. So I'm going to give it up now as I can't think of anything else I can do. Appreciate your thoughts.
....To quote and reiterate what I said in the first link....
"I think one the biggest issue people are having is the mix ratios by being off. The closer that I can get to an absolute equal amount of both parts "A" and "B" the better results that I had. MIX NO LESS THAN 1/2 oz. OR 14.1748 GRAMS OF BOTH PART "A" AND "B"...THATS NO LESS THAN 1/2 oz. OR 14.1748 GRAMS IN THE PART "A" CUP AND NO LESS THAN 1/2 oz. OR 14.1748 IN THE PART"B" CUP. 1/2 oz. or 14 grams..thats it , no less."
If you only poured 7g. in each cup, then you where off by aprox. half. The 14.1748g weight of both "A" and "B" side (not combined weight) would be the absolute smallest amount anyone should pour using RC-3
Brian is the go-to on old resin, he knows how it works best. And absolutely right on getting exact ratios, I broke down and bought a digital scale just to be sure I was doing each pour exact and I do see a difference in the final product. I pour mostly small batches so an off-ratio does mess up a pour.
When I add a picture, I type all I need then post the thread then click the Edit button which opens the full Editor and insert pictures that way.