ScrewDrive Upgrade Kit (New and updated Thread)

If it reach that temp when at idle, and didn’t before - something changed.

It is not given that the motor will become much hotter during actual use as some of the energy is actually used to move stuff, but I would dial down the current at this point myself.

Previously I used Nema17 on my Z which would become hot enough to boil water if I dropped some on the casing. The motor however never complained and is still operational, later swapped to a Nema23 to get added torque / better motor&driver matching.

Yes, what changed is I disabled the fourth switch for Idle power.

So what are your current pots set to? It sounds like you have them all the way up instead of at the 2.8A recommended setting.

I recently disabled the forth switch also. Motors get really hot and hum. They don’t seem as hot when carving. The x controller is also getting really hot.

Yesterday I finally started upgrading my machine after the plates came back from the anodizing process and while looking at the upgrade instructions *.doc I came across the Nut Block installation guide which got me thinking because I do not have a suitable tool at hand that would allow me to hold a Nylock Nut between the Side Plate and Y-Rails so I thought I’d approach it a little different by cutting a flat-blade Screwdriver suitable slot into the tip of a M5x25 Socket Head Screw and insert it through the Side Plate first followed by the Nut Block and a Nylock Nut now recessed in the hexagonal hole of the Nut Block ( the gap between the Side Plate and the Y-Rail is wide enough to allow a Socket Head Cap to fit ).

With the flat-blade slot equipped tip of the Screw now partially exposed past the Nylock Nut I can easily loosen/tighten the Nut Blocks from the outside during installation and maintenance =)

Speaking of Screws… Except for the M5x50 Socket Head Screws required to install the Steppers and some M5x16 Button Head Screws to install the Side Plates to the Rails I was pretty much able to reuse all old screws by simply shifting their location to another place on the Machine thus preserving the pristine black look of it instead of using the Kit supplied silver screws =)

I’m definitely interested. I did not see any aluminum work in any of the threads, which is one of my interests. Is there any examples?

Also, would it be possible to post the maximum capability of a belt driven x-carve vs. a screw driven x-carve, on the same material? I’d like to see exactly what the money is buying.

I’m not sure how to measure MRR. So it would be difficult to quantify. However the accuracy is improved a lot. And the worry of the spindle taking the belts on a walk (overpowering them) is completely eliminated.

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MRR = feed rate x WoC (width) x DoC (Depth) => a volume per minute.

I use ACME and running aluminium with a 1/8" bit I could get good result with 2.5cm^3 per minute. I could go harder but rigidity issues started to show / consistency dropped.

For harder materials rigidity is a major factor because any vibration/runout add to the “bite variation per tooth” which is slim to begin with. For a 1/8" 1F end mill you should be able to do 400mm/min (16IPM) at 16k RPM with a depth per cut = 1mm. Plunge rates must be low unless one can ramp/helix in.

With a 6mm 1F I have done full width cut and 1mm depth at 900mm/min with great success.
MRR = 900 x 6 x 1 = 5,4cm^3/minute
I have also briefly tested same but with 3mm DoC, no complaints.

YMMV :slight_smile:

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Yesterday I managed to finish the upgrade and today I started making the first moves.

Bunch of things I encountered so far:

  • It’s getting hot in here - As mentioned already in the thread, On the X-Controller with the Idle Current Reduction ( 4th DIP Switch ) set to OFF the stock Stepper Motors immediately started to hiss/humm despite being idle and after a short while became concerningly warm - I chickened out and turned the DIP Switch back to it’s factory default = ON
  • Five step left, and ten dB up - As recommended in the Upgrade Thread/Manual, I set the remaining DIP Switches to Full Step ( OFF, OFF, ON ) with matching $100 / $101 settings set to 25.
    With these settings the machine works and is silent EXCEPT for the entirety of the Homing Cycle or at the beginning and end of a simple Jog command.
    Like when I told it to move any Axis along it’s full length ( during lubing ) the first and last half second of the entire motion sound like a new car driver mangling the gearbox whereas the remainder inbetween sounds butter smooth.
    This start/ending noise happens on all Axis in all directions on any location of the Rails.
    Any ideas how to fix that noise issue? Should I experiment with different Step Resolutions ( and matching $100/$101 Settings)?

The GRBL settings I changed from default belt settings:
$100=25
$101=25
$110=3000
$111=3000
$120=100.000
$121=100.000

  • Are your Xcontroller pots set right? They can operate up to warmer temps without issue but make sure your pots are set right
  • the noise is due to the full step and resonance. You can experiment. Even half step will have some. You could go down to 1/4 step but just remember with every increase in steps, you’re decreasing your incremental torque during motion so you may get feed rate limited at a certain point.

So the full step is only the beginning. I recommend that as a starting point for tuning. Most users end up tuning the machine very accurately and end up at 1/4 stepping. The main reason for that is noise reduction as full stepping is more powerful but also much more noisy.
Matching is not necessary but generally will make things look better.

As already mentioned the noise is coming from the “coarse” full step during slow/ initial acceleration and final retardation.
There is also less cushioning of the motion with firmer mechanical connection (screws & blocks vs belts)
One increase micro stepping to smooth things out and 1/4 step is common.

You could also increase the acceleration value ($120-121), to around 250-500 or so.

As far as heat goes, the steppers take a lot of heat and if you dont exceed 170degF during continuous carve then they are quite comfortable.

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@JustinBusby Please define Pots being set right - They’re still on the stock settings from when I bought the X-Careve back at the end of 2016 - If they need a change after the ScrewDrive Upgrade then obviously they’d need adjustment.

@Phantomm Okay… I’ll then give it a try at other Microstepping settings to see if I receive a less cringeworthy noise level =)
Concerning the “matching” of the $100 & $101 to the Microstepping setting - Right now at 1/1 it’s set to 25, wouldn’t a 1/2 need 50, a 1/4 need 100 and so on? ( Maybe I’m missunderstanding something… )

@HaldorLonningdal I’ll be keeping the $120 / $121 250-500 value recommendation in mind once I’ve dealt with the other issue - It’s was just a starting point I took from the Upgrade Manual.
Maybe I’ll be giving a disabled Idle Current Reduction another try but not without some active cooling solution =)

If you go to the “Prepare Controller Board” section, it discusses changing the potentiometer. On the board itself, there is s silk screened diagram showing how the position correlates to output current. You want 2.8A for the stock motors.

And set “Reduced idle current” switch to OFF :slight_smile:
Warm is fine, hot is fine, blistering hot not fine => use lower current limit but keep Idle switch OFF :slight_smile:

Just came back to report that making the change from Full Steps to 1/4 Micro Steps ( and changing $100 and $101 from 25 to 100 to match that change ) made all the difference in reducing the start/end noise level.

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I have a question for people with the screw drive system. Does this affect the “step” appearance on curves that the factory x-carve suffers from. What I’m saying, with better clarity, is the somewhat linear hitches curves tend to show (most easily recognizable in aluminum) which I’ve wondered was caused by the belts. I’m curious if this smooths that out.

Also, any word on the next batch or when I need to get on said list?

The source can be a few things. The cad. The cam. The setting on the machine.
Start from the bottom and work your way up.

But to answer the question if you set the stepping to match the old belts the resolution is (x4) I believe.

So what is the word on the next batch? Need to budget myself for the purchase. Did I miss it somewhere?

edit: I notice there is a link above that appears to be working, but your main page doesn’t seem to have any content on either of my browsers?

Also, quick question… I notice most everyone is using the factory NEMA 23 steppers with the screw drive kit. Are there any advantages to using a 270oz stepper with the screw drive?

Moah powah. So yes a little. But I’m not entirely convinced. Even though I got the bigger steppers.