JD's Garage DIY CNC Plasma table build

[DAPPH]

I bought the plans and am collecting bits and pieces. But I also plan on making the bearing blocks out of aluminum. I have a home foundry and have cast a fair amount of things.

One possible method is to 3d print the bearing blocks and then use those as a pattern to cast them in greensand. However, due to the unavoidable shrinkage of the aluminum, I was wondering if anyone has a drawing and dimensions for the bearing blocks. I'm sure I could print them, and then reverse engineer the optimal dimensions to end up with a good casting, but if a drawing with dimensions is already floating around, I am not opposed to saving time.

By way of introduction in my first post, I'm an optometrist (somewhat retired) and I also have a nice machine shop. But no plasma table, which would really add a lot to the workshop's capabilities.

If you have designed it parametrically can you adjust the percentage of size to compensate for the shrinkage .......... say 6% bigger ?

Pattern and Shrinkage for Aluminum Casting

Here's one for those of you who have casting experience. I want to make an aluminum part in some quantity but need to make a mock up first. We are talking about something about the size of a fist or two; perhaps 1.5" to 2" in two dimensions and about 3 or 4 in the third. It will probably...

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