Here is a chapter on lost foam casting, may contain some useful info Has anyone tried to buy coating from Foseco, I see no reason why they wouldn't sell a pail or two, they have distributors and reps everywhere
I have the whole FOSECO Foundry manual, IIRC, thanks to you. I would love to experiment with a commercial grade LF refractory coating. I tried to buy the FOSECO STYROMOL 169 via online and via direct inquiry......they wouldn't give me the time of day. I need to get one of my pro-foundry buds to do the deed for me. Best, Kelly
I forgot to mention, after going back and rereading that section, it reminded of the potential issues with LF iron casting and the potential for interactions with the decomposing foam introducing carbon defects. Sounds like some of the pattern materials reduce but don't entirely eliminate the issue. Also, the greater potential for gas eruptions back through the sprue with iron LF. The other general comments that rang true: How the permeability of the coating has an important influence on metal propagation speed and how too much or too little can adversely affect the casting process and quality. It is amazing the relative quality possible with just drywall mud but I have no idea how it compares to professional coatings in this regard. I suspect it's low just because of the black film residue typical present (at least on my castings). I don't notice a big difference in fill times with uncoated patterns but definitely do with vacuum assisted casts. The degree of experimentation required with spruing, treeing, pattern orientation, and vibration to get consistent results. I did get a kick out LF being characterized as odor free......not in my world and compared to what? Furan? Even though it's lower capital cost than setting up a conventional foundry, LF won't displace conventional sand casting if the cost comparison is based upon the casting alone and not elimination of other downstream costs......excepting finding its place in complex parts. Best, Kelly