Testing the new magazine!!! designed and 3d printed my own version of the Forks for the toolholders…
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That’s just insane 
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Next up: someone needs to do it on the Nomad 
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That’s really impressive. I can’t get a sense for the height of the magazine… does it make loading stock difficult? Do you move it out of the way?
Vince! Your turn! 
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very nice.
what are you using as a coolant for the mister/sprayer?
Super inspiring! At this point you really should replace the steppers with clearpath servos 
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You guys are soooooo far above my head in this…but this is definitely eye candy and fun as hell to watch you get your funk on! 
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I wanted to ask a question about your spindle change rack. When you put your tools in your holders do you have to set the stick out the same for every tool for the spindle changer to work properly or does the BitSetter work for your spindle changes.
you have 2 options, one is to leave the touch plate (Bit setter) enabled in automatic mode, so every tool change it will go and check the tool’s zero point, the other option is to measure and store on the machine the tool length offset… but i know i will make a mistake and trash a job, sol i prefer the machine to loose some seconds and check every time…
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why did you do this, i now have something else to do!!! THANKS!!!
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They can be set up to run on just step and dir or using I/O pins so should be a drop in replacement with your current setup
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they look awesome, i will think about it
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If you want to replace your steppers with servos, but don’t want to break the bank, these are great units at the fraction of cost of the clearpath’s.
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I would say that closed loop control has such an advantage that I would need a good reason to install an open loop control mechanism on a CNC machine now. Given a machine controller that can break out the step / dir signals for external motor controllers the difference to closed loop is relatively small in cost compared to the large operational benefit.
The venerable Longs Motor Co has closed loop steppers on AliExpress at pretty fair prices, stepperonline has a good range too.
On a Shapeoko sized machine the extra benefit of a servo motor over a closed loop stepper might be harder to justify. The main differences are that a servo will likely be able to run quite a bit faster in rapids and will attempt to return to the set position if load or accelleration push it off course, whilst a stepper will just throw a fault alarm and stop if it misses steps. Whether the Shapeoko frame is up to the higher forces from a servo motor setup without introducing more deflection is a worthwhile question though which I’m not qualified to answer.
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A quick follow up on that with some more practically useful stuff;
Since Luke pointed out the additional motor load presented by having to accellerate the mass of the ballscrews I went reading, there’s a range of calculators out there which help determine the motor power required to meet a given linear motion requirement, moving mass, accelleration etc. but it’s key to include all the masses in motion, especially those which are spinning quickly as they take a lot of torque to overcome.
This article is a good starting point for what to include;
Oriental motor covers much of the same stuff here, but with the maths;
There’s a bunch of calculators online if you don’t enjoy Excel, here’s one example;
https://www.h2wtech.com/page/linear-motion-calculator
At some point I’ll weigh the various parts of my Shapeoko and figure out what the moving masses are…
One key design constraint is the selected ballscrew
There are maximum tension and compression loads for the screw before things go bad, this limits accelleration, but I suspect this isn’t the limit on our machines.
There is also a maximum rotational speed for any given ballscrew before it starts to whip, this is the first resonance of the ballscrew and is well described by most of the reputable vendors, here’s HiWin, the maths starts at pg 23;
The critical speed is discussed on pg 31 and fairly easy to calculate, for example, if we put a 1,000mm long 16mm ballscrew on a Shapeoko XL / XXL long axis with dual axial contact bearings fixed at one end and a floating regular roller at the other we choose;
Mf = 0.689
and our first resonance speed comes out as;
2,469RPM
To which we’d apply a safety factor between 0.5 and 0.8 according to the guidance and that would give us on a 10mm screw;
206 - 329 mm / second speed on that axis, assuming our motor can do that
So, it should be quite feasible with a bit of measuring to choose a well-matched closed loop motor, either stepper/encoder or servo for all three axes of the Shapeoko, which won’t whip the ballscrews but can keep up with the rapids speeds and move accellerations we want to see.
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Thanks mate!!! 
Modelled my machine so i can plan some improvements, i know it will never perform like a proper mill, but i want it to reach its potential…
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I’m curious, why is the mount for the X-axis motor above the two linear rails? In most designs I’ve seen, the ballscrew sits between the two linear rails. I assume this balances everything better.
Was this something you went out of your way to do for some reason or did it just arise from some constraints?
Also, why the recesses on the Z-axis carriage? To make room for screws and/or reduce weight?
Location of the ballscrew makes little to no difference, especially on a hobby cnc like shapeoko. The load of the Z axis carriage is supported by the linear bearings not the ballscrew. Besides, it was simply easier to add a ballscrew above the extrusion rather than trying to fit in it between the rails - speaking from my own experience.
One thing that could help however, if he wanted to gain more Z clearance, would be to install larger x axis extrusion, say 50x100 or even better 80x160, that would allow for a wider spacing of the linear rails.
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