The addiction gets worse when you actually start casting! Best, Kelly

Thanks Bob. I kind of went crazy on the gating on this one and could have gotten by with much less of it but when you're looking for one part, it's take no prisoners! Best, Kelly

I bought the moldable ceramic fiber from my local refractory supply distributor. It was Inswool (Harbison Walker brand) but there are many, like Kawool, Fiberfrax, and others. They are all air setting moldable alumina silica mixes, usually available in a caulking tube, 1 gal, 5 gal sizes. Moldable is putty like, and pumpable is like pudding. Moldable works best for forming shapes, pumpable as glue, filling cracks and patching. It can be bought online. Search "moldable ceramic fiber". You'll occasionally find it on eBay and Amazon. Shop price.....it can vary significantly but is all the same stuff. Best, Kelly

@@kellycoffield533 I sincerely appreciate your responding to me. You get back to me faster than I can catch up. :)

Try Kronick in MInneapolis.

Yes the sand stinks. I store it in the flasks which are modified sealed lock ring barrels. Labor intensity really depends upon how many parts you make and how you make the patterns. For instance, if you have a cnc program to cut repeated foam patterns is that labor intensive? But let's face tit, making one casting with any method is labor intensive. Also, a huge time savings in lost foam is demolding. You literally just dump the flask and when you quench the hot casting all the refractory coating falls off. Compare that to the labor to demold and clean up a shell or investment casting. The furnace has limit switches. They're just set at maximum travel limits which isn't needed for small crucibles so I don't always use the limits. Best, K

To compensate for aluminum shrink, the pattern is made 1.3% larger than the desired casting size. Best, Kelly

As much as I like casting, I'd buy the beam and form it, or possible fab and weld it, especially for one piece. For a piece that large, it would be much less effort and a higher integrity part. Best, Kelly

@@kellycoffield533 yes i thought of the but its a complex part... thanks..your parts are coming out nice now. you have become very good at what you do:)

@@douglasfurlong1 Wasn't trying to be a wise guy, but a curved I-Beam doesn't give a guy a lot to go on but in any case doesn't strike me as a complex shape, but anything 7 feet in one dimension would be a challenge, especially for a home/hobby caster. Cost, time, weight/eqipment, size of melt, all dramtaically increase with a part that size. I dunno if that is a 2" or 10" cross section I-Beam but In my view, it could done at a fraction of the time and cost if it was formed or fabricated and would be a superior strength piece. Best, Kelly

1375F to 1450F. Lost Foam typically requires 100F-150F higher pouring temps than conventinal sand casting. Best, Kelly

Fluidizing the bed is fine for removing the casting from the packed mold or possible placing a pattern in a filled flask but it's the opposite of what you want to do a tightly pack a mold. Vibration makes the mold media act like a solid. Fluidization makes it act like....well, a fluid. When you turn the fluidizing air sytream off, it isnt packed but more akin to having just poured it into the flask so it would still need to be vibrated to have good mold stability and integrity. I had a fluidizing coil in the bottom of my old molding rig. I never used it because I still needed to sift all the sand between uses to remove any loose refractory coating or clumps resulting from the byproducts of the decomposed foam. To filter the sand, I just cut the bottom out of a bucket and replaced the bottom with a perforated plate/screen, place it on top of the storage bucket, and shovel the used sand through it. I also found that with hand placing and filling the pattern, I was better able to avoid pattern damage and deflection than trying to place in a fluidized mold. Best, Kelly