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I remember in our high school shop they had some casting clay that was deep red in color. It was very fine and had a sticky consistency like clay.
Yes, me too. I recall that after use, only the tiny bit of sand in direct contact with the molten metal would get rock hard. We simply sifted the mold sand through a screen and returned it to the "sand pit". It never dried out just sitting there, so I believe some kind of heavy oil was mixed into it. It did smoke a bit during pouring.
it simple. mix some sand with waterglas. it will harden. how fast depends on temperature. co2 "cures" water glas as well. you can stick some straws in the sand and blow co2 in there. (i have never done it, so no idea how much gas you need.)
I watched a youtube video of a guy using molasses and sand. He has some videos making some really nice looking castings.
Have never tried it but looks interesting.
What a lesson on molding got from this video. Very interesting concept and certainly he looses the stuff that gets "BLCACK: because of the molasses burning but most probably will give a lot of strength to weak areas on the mold. Very worthwhile to watch. Also sad with the working conditions. Maybe a lesson for many that have not been much out of the country to be thankful for what we have in spite of some poor government officials and lack of our involvement on voting them in or out.
Recommend to watch this if you do some molding. I will try his molasses method. Too bad there is no verbal explanations to add.
It is somewhere in Pakistan, and I have worked with some Pakistani Craftsmen crews and there were often some individuals that really made an impact watching their ingenuity and dedication.
Not a lot of help, but when I was casting I went and dug up some sand from the local sandy place
Fortunate to live where the Mansfield Red moulding sand vein runs...
Dave
Dave, thanks. Coincidentally about 33 years ago when I started to build the Ginger's lathe and milling machine and run into a good luck one day driving by the side of the mountains.
I ended up with a perfect mix very tolerant of my lack of molding experience and maybe one or two casting only had to be re-done. I used BBQ charcoal at that time. Now my new built gas smelter got 3 or 4 pounds of aluminum in 20 t 25 minutes with one burner form a Turkey fryer burner. I am still to hook up the second.
I think that making a larger jury rigged kiln would be the best approach so far, unless I hear a better idea.
Another option I get is when I go to Ontario-Canada this summer to make a HUGE wooden fire with hard wood and make the pieces crumble before the really melt. Then melt and pour on the baking try to make the ready for winter casting here.
Thanks
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