Some of things I cast from my home foundry, inside the core box I have placed patterns for a rosette, downrigger weight and scuba weight mold.
My preference of scrap aluminum is automotive, most of my patterns are counterfeit, in other words reworked items that I had purchased. If you look closely at the downrigger and scuba mold you will see the rework done using Bondo the famous autobody filler.
By casting my scrap aluminum into a product that sells, I'm averaging $19.00 a lb instead of $0.70. there's a good forum on backyard foundry for those who care to learn more on the subject.
Anyone with a sharp eye can tell that the pattens or rather the sprue is located on the wrong side of the patterns which means if there was any floaters in my molten aluminum they would have found their position on the inside of the scuba and down rigger molds were the surface area should be free of debris.
Pouring from the other side of the pattern would assure that the floaters would be on the backside were they could be easily removed with out causing any blemishes to the inside of the finished mold. Sometime even the inexperienced foundry-man gets lucky this pour tuned out perfect with out any imperfections inside to molds.
The ebayer started his backyard foundry about the same time I did and often found myself bidding against him for the same item ( pattern ) to add to our product line.
http://www.ebay.com/itm/6-LB-Downrig...item2570ef162c
There you have it Foundry 101 in a nutshell.
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