I have seen some in this "hobby" invest heavily in some very expensive lathes, mills, and other machining equipment.
I have a very modest Grizzly lathe, mill, and tooling, which I inherited, so no cost.
I have put my hobby money into building a commercial-grade iron foundry, and while that has not been cheap, I probably have less money invested in equipement overall than some of the high-end hobby folks.
The furnace, burner, and miscellaneous equipment were not that expensive.
Commercial mixers on the other hand are really outrageously expensive.
At the time I purchased my large mixer, I had more money than time.
At this point, I have more time than money, and so if I had to do over, I would probably have made a mixer.
Many use modified concrete mixers, and those actually work ok, and are relatively inexpensive.
They are big and bulky, but have a significant mixing capacity, if you need that.
I use resin-bound sand for everything, so I mix the same sand regardless of whether it is for cores or molds.
It is clean, dry commercial foundry sand, so not a problem with anything getting snagged in the mixer.
I did actually take my wife's KitchAide mixer, and I use that for small batches of bound sand.
I had to buy her a new mixer, in order to stay married.
I found a used commercial kitchen mixer, and purchased that.
The shop where I bought it asked if I needed help getting it into the car.
I said "No, I can handle it".
LOL, it took five people from the shop to muscle it into the back seat of my car; total weight I think is in the 300 lb range, which is far heavier than it looked.
My large mixer came with a wire attachment like shown on the right in the photo above, but that was not rigid enough to mix sand, so I made my own paddle.
For my small mixer, I use the attachment shown in the center of your photo.
A few photos of my large mixer, and fabricated paddle.
It does not really look like a heavy mixer, but trust me, it may as well be made from a solid block of iron, and it is every difficult to move even a small amount. The weight does keep it in place on the floor while it is mixing.
I put my molding stuff in a small shed, just to try and keep the sand and grit out of the main shop.
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