G-Spot
Thank you. I gave it some thought, but I didn't expect it to be such a significant issue. I'll definitely look into that. Thank you for the video - I will check it for sure.

peteeng
Thank you.

I apologize for not including the basic assumptions and information about the project in my initial post. I am aiming for a hobby-level machine that can cut steel, soft metals, and wood. It's hard to specify the exact parts - it could be a steel gear, a wooden sculpture, a brass trophy, or pretty much anything... If I had to compare it to a benchmark machine, it might be something like the Tormach 770/1100. The Haas VF1 is fantastic, but I cannot imagine the required stiffness for utilizing its 22kW spindle at its full power.

I used 32 GPa for concrete and 210 GPa for steel.

I need to review the ASME B5 document you sent, but it will take some time. For now, I've skimmed through it and, if I understand correctly, I should measure the deflection at the center of the work zone. My current setup is quite different because I measure at the maximum extreme positions of the work zone. I've attached images showing my current setup of fixed and force constraints.

Why use concrete for the base and column? There are three reasons:

1) Ease and safety of manufacture - It might sound funny, but it's due to the fact that I currently live in a small apartment in a multifamily building on the 3rd floor, which, strange as it may sound, is a real constraint I must consider, at least for the near future. Using concrete avoids fire hazards, toxic fumes, omnipresent steel dust, and noise from welding or grinding. Concrete seemed to be an easier material to work with inside my apartment. Moreover, I have no experience in welding, while creating a mold for casting seems easier.
2) Cost - Concrete is cheap.
3) Vibration dampening as an added bonus.

Why a column design? It’s a compact design that fits within the limited space of my room.

Why is the column (and also the base) hollow? It's a compromise. I chose this because I wanted to reduce the weight, as I don’t want the machine to risk falling through to the floor below. I’ve run numerous simulations and found that I can reduce the total weight of the base and column from 624 kg to 405 kg (from 1376 lb to 893 lb) without losing much stiffness:
- In the X-axis, it drops from 9 N/µm to 8 N/µm.
- In the Y-axis, it drops from 11.5 N/µm to 9.5 N/µm.
This comparison is based on my current FEA setup. I expect the results might vary with a different setup, but generally, I anticipate that filling the voids yields diminishing returns.

Regardless of my current reasoning, I am open to a complete redesign or may consider postponing my project for an undefined time until I have access to a garage with more space to potentially weld the machine.

I will read the document thoroughly and repeat the FEA.

routalot
While choosing the spindle, I plugged my most ambitious cutting parameters mentioned above into this calculator: https://www.kennametal.com/us/en/res...and-power.html
, and it indicated:
- 1.12 Nm (9.96 in-lb) torque at cutter
- 0.47 kW (0.4 hp) spindle motor
So, to have some margin, I am thinking about a 1.5 kW motor.