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Chemtane vs Propane for casting

I have recently moved from Oxy/Acetylene to Oxy/Propane (after 37 years) and I like it pretty well so far. I was trying to melt some platinum and could not do it fast enough…I mean it was taking forever and used a ton of oxygen. I am wondering if anyone has experience with Chemtane. I have used Oxy/Acetylene for castings (gold and silver) in the past many years but am anxious to leave it behind. I have not done a casting yet with my oxy/propane configuration but I have no doubt it will work fine however I want to try Oxy/Chemtane as a standard casting setup. My limited research so far says Chemtane has a higher BTU output than propane so it stands to reason it’s a better option for casting and melting platinum. I’m hoping to hear from someone with experience first before I spend the money and also learn any pros or cons. Appreciate any info. Note…I searched the site and could only find 2 scant references to chemtane. Thanks!

I used oxy/Chemtane for about the past 4 years and highly recommend it! I don’t do much casting, lots of fusing argentium and high karat gold. Definitely hotter than oxy/ propane, very easy to control. I think it would be a great option for you. I recently moved to Durango, CO and cannot get it here. So sad.

Thanks for bringing up this subject, which is new to me. Apparently, from my research, Chemtane is propane with a few additives that do indeed make it burn hotter and with about 40% less oxygen use. The MSDS seemed to indicate that it does not have the same odor as propane, only a “mild gasolinelike smell”, so it might be important to be aware of the odor in case of leaks…propane pooling lower than air can be a deadly explosion hazard. Why they didn’t put a recognizable odor additive as in propane makes no sense. I also found some discussion of this over at the glass forums…those folks need more heat than we do…and there is another alternative, propylene, which is even hotter, cleaner (important with Pt) and more efficient. I suppose in the end it depends on what’s available where you live, what it costs and how well you think it works for you.
Oxy/propane will certainly work for melting platinum, but you may need a different tip to get more BTUs…we had a recent discussion on here where someone had a platinum tip for a Swiss torch which required 43 psi of oxygen, which she could not get out of an oxygen concentrator. So in the end, it will all be down to the various tradeoffs. If you are casting in platinum, a little extra expense for a fuel gas may be the least of your worries. I did find that some folks were not allowed to fill their 20 lb propane tanks with Chemtane or propylene and had to purchase a new tank for that usage. Thanks again for the heads up on this interesting new wrinkle! -royjohn

Thank you Loriejmt… You told me just what I needed to make a decision. I am going to move to chemtane now instead of propane for all my work…not only casting but bench work too since it sounds like it’s a good all around platform. The nice thing is it has the same connections as propane so it’s easy to make the switch. The major up front investment will be the tank…as Royjohn mentioned you can’t use a propane tank. Our local gas and welding supplier quoted me just over $200 for a full tank and then about $38 to refill it going forward.
Incidentally…I use a Smith Little Torch for all my bench work and a number of years ago tried using it with the multi port tip for casting gold and silver and have had great results using Acetylene (that might make some cringe given some opinions on the Little Torch I’ve read on other threads…but for 3 oz or less castings I do it’s worked great). Since I’m abandoning acetylene though, and I had such trouble melting a small piece of platinum with propane, I am excited to try chemtane. And royjohn, as per what you mentioned…I do think the Smith Little Torch does not have enough horse power to melt pt with propane effectively. It’ll do it but far too much effort…I was just getting it to melt and I ran out of oxy (and I had plenty when I started)…hence my interest and investigation into chemtane.
Also…for any interested, there is now an adapter for the Smith Little Torch to use Meco tips. I’ve been using that set up since I moved to propane and really like them a lot. It’s made the SLT even more versatile.
I’m interested to have just one torch set up where I can do bench work and then 2 to 3 oz castings. I will never give up my SLT for the bench, ever…so if chemtane doesn’t give the extra needed horsepower for the small castings and small platinum work that I do, I guess I’ll have to give in and add a bigger torch to the shop.
I’ll let you all know how my experiments go with chemtane. Thanks again for the great info.

$200 for a tank seems like a lot to me. I might look for someone selling a chemtane tank used. Also, you might want to check on Mapp-pro. Mapp gas has been discontinued, but now there is Mapp-pro, which is propylene, which is even more efficient, cleaner and hotter than Chemtane. So look around and see what’s cheapest for you. You mighht be able to get away with simple 1 lb tanks of Mapp-pro, if you use a full tanks when you cast…to avoid running out during a cast. Then you could use up the rest of the tank with your regular jewlery work with the SLT. I think if you check, you can find the rated BTUs for the SLT rosebud tip and Paige can tell you if their tip gives more with the SLT. If I remember right, Smith says the SLT will melt up to two ounces of gold with the rosebud tip. Going to platinum, which requires more heat, I don’t think you are going to be able to get to 3 oz melting capacity, but if you look up some literature on Pt, you can probably find a recommendation for the number of BTUs needed for casting various amounts. Regardless of the tip you use, the SLT is just a smaller diameter all the way through, so there is a limit to how much gas you can push through it. Take a look on line, the manual for the SLT is easily available and the psi and BTUs for the various tips are listed. At 3 oz. of Pt, you are talking about 1350 grams, which would be the equal of $2300 worth of Pt and it would be the equivalent of 100 gent’s rings. What are you planning on making, a Pt Cinderella slipper? If you go that big, you will need a bigger torch, I suspect.