The machine you built is very professional looking! Great job! I wish more people did high quality "last mile" integration" on their machines. Energy chain and powder coat makes a huge difference in perceived quality.
Couple of questions:
1. Why did you chose to mount the Y axis servos in that orientation instead of where the axis of the servo is perpendicular to the floor?
2. Since you welded the frame, how did you manage the mount the linear rails square? Shims? Post weld machining the frame via bridge gantry?
3. What was the total cost of this vs buying an OTS machine? I'm guessing around $12k.
1. How the Y-axis Servos are mounted isn’t the ideal orientation. Some of my initial decisions, ie for linear rails, limited my options based of what I was able to fabricate in-house. There were a lot of lessons learned and if I was to do it all over, I would actually go with mag driven linear servos if I can afford them or have the same existing Servos mounted in vertical orientation with the gear rack facing outwards engaged with the pinion
2. Good question! One of the biggest challenges of starting to make your own machine are the real life unknowns, which might yield one answer theoretically, and another in practice. Trying to balance between a realistic budget and wanting a unicorn setup, I realized that it was out of my budget to machine the entire base frame for this machine. So, the Y-axis gear rack was basically mounted to base frame using self tapped holes, some shims from McMasterCarr and very long hours with a Mitutoyo dial riding back and forth. Since the gantry was much smaller compared to the base frame, I was able to get the X and Z axis machined from a local shop. Here’s pix of that: https://imgur.com/a/RLEETAm. Due to the DIY nature of my project, I was also not able to stress relieve the weldments but was still able to achieve 0.001” tolerance for my use case materials (with the exception of aluminum which is probably around 0.01”).
3. Having made some mistakes along the way and doing this for the first time, my actual expense was around $23k over 1.5 years. However, that also includes a very nice 2x high volume Busch 20kW vacuum setup for the vacuum table (which I got for a steal deal on eBay). They would normally run $20k/ea but I was able to find and fix DOA units with minimal work for around $1600 for both.
Thank you for the extra photos and info! It really helps. Especially with the notes on the motor mounting. Have you spec'd out Linear motors for your machine? I have been eyeing Yaksawas's product. But I'm scared to RFQ the product due to sticker shock :)
Couple of questions:
1. Why did you chose to mount the Y axis servos in that orientation instead of where the axis of the servo is perpendicular to the floor?
2. Since you welded the frame, how did you manage the mount the linear rails square? Shims? Post weld machining the frame via bridge gantry?
3. What was the total cost of this vs buying an OTS machine? I'm guessing around $12k.