I recently bought a 2nd X-Carve and the Y Carriage seems to be lacking the holes for mounting a NEMA-17 stepper motor for the Z-Axis which my 1st one has. Does this apply to all of the new X-Carve machines?
While probably true for a carver, in one of my applications where the the framework is being used for something else, NEMA-17’s do just fine. The machine doesn’t experience loads that a carver would. But you didn’t answer my question.
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This is a question for Customer Support or Sales.
The under-experienced desires explanation.
While I dont have an Xcarve myself my first CNC had Nema17’s (49oz) and an Arduino G-shield with A4988 drivers. The holding torque and general strength of that combo was not enough to overcome carve forces / vibration. It could drop steps and just wasnt steady enough. It could carve some metal/hard wood but it didnt take much to make it drop some + you needed to carve light = long carve times = more time for issues.
I did upgrade to DRV8825 drivers but this didnt help me like I hoped for.
It was not untill I changed to more capable drivers + Nema23’s my machine really transformed. It cost me roughly $200 with new motors and new drivers as I built my own controller.
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I understand all of this. As I wrote before, one of my machines is not a carver though it is based on an X-Carve framework so it never experiences forces like a carver does. The NEMA-17 steppers do well in this configuration. I don’t see that machine ever being used as a carver as I am building another one to be used as such and it will be more beefy in the stepper motor department.
I’m willing to guess that it is usually the X or Z that is losing steps when NEMA-17’s are used on the X-Carve. The Y uses dual steppers and so, potentially, has twice the torque of the other two axes. The NEMA-17’s that came with my 1st X-Carve are 89ozin while all of my NEMA-23’s (of two types) are 178ozin. Ganged together, two NEMA-17’s have almost exactly the same torque as one NEMA-23. So I am thinking about robbing my 1st machine of its X and Z NEMA-17’s and replacing them with two NEMA-23’s from the other machine. I could take those two NEMA-17’s and use them for the Y axis on the 2nd machine while putting NEMA-23’s on its X & Z axes. It would also balance the current better as I doubt that my 2.5A driver can adequately push two NEMA-23’s anyway. What do you think of this plan?
Since one NEMA-17 needs about half the current of a NEMA-23, according to Ohm’s law, two NEMA-17’s wired in parallel will require about the same amount of current as one NEMA-23 and generate about the same amount of torque because the two are generating force in the same direction and this is additive. So with one NEMA-23 driving the X, one NEMA-23 driving the Z and two NEMA-17’s driving the Y, all three axes will use about the same current and generate about the same amount of torque and the system will be well balanced. When you use an X-Controller and you put NEMA-23’s in all four positions, you end up with twice the power on the Y as you do the X. This doesn’t make sense to me because you should generally expect to need the same same amount of force/power on the X as you do the Y. The Z is a different matter because mostly what it needs to do is to lift the cutting assembly against gravity but, on the other hand, it is generally geared lower as it is on a lead screw instead of a pulley with belt.
Seems to me that you are trying to drive your machine beyond its limits. With a 3/4" bit on oak your machine would need every part of it to be larger gauge, especially the belting system. But that’s just my opinion. I have no aspirations to use more than a 1/4" mill bit on my X-Carve. I just plan to use more passes. With a CNC machine, you can do a lot of things with programming so I am thinking I don’t need those fancy molding bits that came with my Craftsman router I bought many years ago and are still sitting in their box. I think I can get by on just small end mill and ball-nosed bits.
Let’s get to upgrading that machine Phil.
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That would depend on what your asking me to do with those fingers Phil.
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Haha thanks for taking that bullet Bob
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Send me the file.
Wouldn’t donkey power be more fitting?
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You using the shellac and acrylic technic.
Well I’d like to help but I think that moves beyond my current skill set lol. Anything I can do though I’m here. Well in California that is🤦♂️
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It is a shame that a rod can’t be passed between the two Y-Axis steppers because the Z-Axis carriage is in the way. If the gantry side plates were made an inch taller, the steppers could be placed underneath the Z-Axis extrusion instead of in front of it. The two motors could then be joined with a shaft and you could actually use one motor to drive both sides or two motors that would assist each other. It would also give you more range in the Z dimension. The plate could be made narrower front to back and that would give you more range in the Y dimension. But the narrower base might make it less rigid. You could keep the base the same and the machine wouldn’t change much but it might solve the double-current problem for the Y axis.
True, my mind is running opposite of itself.
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I think you may be in the right place for that. Join the club. 
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After some agonizing over this, I decided to bite the bullet and design some new gantry end plates. These raise the gantry by 70mm. After pushing the Y-axis stepper back by 35mm, the shaft will clear the the Z-axis assembly and a rod can run between both sides. Since I will only need one stepper to drive the Y-axis, I will use a bearing on the other side. All axes will use single NEMA-23’s. This will give this unit an extra 70mm clearance for taller work volume. So that I can use the stock Z-axis assembly, I will need to bring it down farther, and that means I’ll have to mount the Z-axis stepper on top of its mounting plate instead of underneath. I’ll then use spacers to get the pulleys lined up. I will space the Y-Axis Motor out to make room for a shaft coupler and place two pulleys on the shaft that will deliver power to the passive side. I already have materials on order.