Just the drivers.
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You shouldnāt be missing steps every on the y axis with the standard drivers. Can you send a video to support? Thereās likely another cause.
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Hi Daniel,
I have already sent support a video 2 days ago. If you can push them to take a look, that would help me get going. Thanks
Thanks, Iāll ping the support engineer about it
I was having trouble with my z-axis missing steps. I measured the actual current and the small stepper drivers only deliver 1.5A. They are suppose to deliver 3.5A, so Iām wondering if somehow some chinese knock-offs made there way in there.
Anyway, I replaced the z-axis driver with a $15 TB6600 based driver I and it delivers 3A no problem. Later I plan to replace the y drivers as well but I might not run them all the way to 3A, since the idle power usage will go up 4x and no need to run them that hot.
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This gave me 2x the torque for the z-axis and I have not missed any steps so far
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let me know when you upgrade the Y drivers as well. I had a couple of spare new DM860T from Stepper online that I tried to replace the existing Y drivers, but they failed to work. I tried different switch settings, but nothing I tried was able to run the motors. The funny thing is that the driver showed no alarm and they were powered, but no pulse to the motors. Not sure what was the reason, so I swapped back the old one and all was working. But still planning to replace them with better one, but dont want to spend $99 for the high power one that langmuir sells. I need to find the exact same replacement in amazon to save some money. THese DM860T have way more settings that required. I am now looking at DM860I or DM860H, but not sure which one will be the clone of the langmuir one.
Those DM860T drivers really should work unless wired wrong. I had a quick look at the data sheet, the only reason why I donāt think they would work if the jumper settings inside is incorrect. Documentation shows that internal jumper J1 should be shorted and J2 and J3 should be open. The only other thing I can think of is the input voltage may be a little too low since it requires at least 36V according to the datasheet, but I donāt think this is a problem.
I will let you know when I upgrade, but I have other issues I have to deal with first.
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I triple checked the wiring and I am sure they were correct. I did not mess up with the internal jumper though. I felt like the unit were disabled for some reason, even though the Ena input were disconnected which means enabled by default. Not sure what was the issue. Anyway I returned them.
you have links to this driver?
The one I used is a TB6600 based https://www.amazon.com/HiLetgo-TB6600HG-Stepper-Controller-Replace/dp/B01N6AIEQT/ref=sr_1_3?crid=HDB7FHFA5LE9&keywords=hiletgo+tb6600&qid=1676484763&sprefix=hiletgo+tb6600%2Caps%2C134&sr=8-3
To wire it up:
on signal side:
5V => black wires that were in DIR+ and PUL+ (both black wires go into this slot)
CW => direction
CLK => pulse
EN => leave open (enabled if open)
on driver side
+32V => wire that went to VCC or previous driver (36V black)
GND => wire that went to GND on previous driver (white)
A+/A- (red and green) and B+/B- (blue and yellow) same as previous driver
For DIP switch you want 8x microstepping so M1=>on, M2=>off and M3=>on.
The potentionmeter next to the DIP switch sets the actual current and should be rotated all the way clock wise for full current. Being able to set the current with fine resolution is actually nice because it can sometimes help when a stepper motor resonates and adjusting the current slightly can help. M4 on the DIP switch sets full or half current of the potentionmeter value. I do not remeber the polarity I think it should be on for full current.
The PCB shows +32V and the Langmuir supply is 36V. This is not a problem. If you pull up Toshiba TB6600HG datasheet you will see that it is recommended max. 42V and can handle absolute max. of 50V. The electrolytic capacitor is also rater for 50V so having 36V on this driver should not be a problem and I have had no issues so far.
That being said, this may also be a fake TB6600HG chip, but I have no issues so far and have used this on other projects. If it ever goes you can always get the actual chip from digikey or mouser for $6 and solder it on under the heatsink and know that you have the real deal. Be wary of drivers that have a black enclosure box and advertise as TB6600HG. If you open the box you should see a big chip with a metal base to attach to a heatsink (see TB6600HG datasheet from Toshiba), not a small square chip with no metal that the top side is squished onto the heatsink.
If the motor is turning the wrong way, just swap the A+ and A- wires where it connects to the driver. If you ever lose track of which signal is pulse and which is direction, they are labeled on the Langmuir controller PCB (right by the connector).
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Is upgrading the drivers a confirmed fixed for X/Y axis problems?
I installed the high power Z axis driver as part of the initial build and the Z axis is also the only axis that doesnāt stall on me. I do have issues where both the X and Y axis will stick and the steppers skip steps. Iāve checked my backslash to be at the maximum spec of 0.0003". When the sticks happen, I have been able to get it unstuck by trying to move at low ipm in the opposite direction of travelā¦ it usually takes half a dozen back and forth attempts to get the axis unstuck. There doesnāt not seem to be a clear pattern of when the sticks happen. It has happened when the garage is 60f and when the garage is in the low 70s. However, it does seem that once a jam has happened and been āfixedā that axis is typically fine for the rest of the day. Iāve been meaning to write a warm up gcode routine to see if that prevents it from happening. Iāve been wondering if it is a [lack of] torque or perhaps and issue with ball re-circulation in the bearings. I just got an order of 4mm zerks but havenāt tried to grease the linear rail blocks yet.
Id check the squareness again and check the linearity of your x axis rails to one another. Should not stall.
I see it happen on the Y axis as well. The X/Z carriage casting is very rough on the bottom and actually drags on the X frame on the far side of travelā¦ Iām unsure why it only happens on one side but it has never stalled in that position.
I donāt get it? Mine works great. I did upgrade to the big drivers on the Y and X. Seems to be more powerful than before.
I use it everyday without any problems.
Except for the SMW vises. I would buy another one.
Very good to hear you would buy another SMW vice 
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Can one of you guys give me a little advise and expand on what you mean by āstalls or missed stepā How did you detect this? I have turned in a ticket because I thought the machine was actually losing its work zero but if I am understanding correctly my axis is actually missing steps because its under power. So lets just say I am cutting 5 different parts that are the same. I set up a stop block, set a part and cut it. I put the next part in and kiss off the stop block, send my spindle to xyz zero and I could be off .120". Could this be from āstalling or missing stepsā??
That is probably missed steps, but could be other things as well.
If you home the machine does it come back correctly or is it off still?
Does the machine make any pops coming from the home position like itās binding in any way?
Home the machine and note the orientation of the couplers on the ballscrews. Move the machine to the front right corner of the machine and home it again. Are the couplers in the same orientation or are they clocked differently?
I have noticed all kinds of odd stuff. Yes most time it seems to come back correctly after I rehome BUT with that said I have had to rehome several times before because it did not appear to take although its hard to tell when its in the .0??" range. A few times I home the machine then set the tool and it asks me to home before setting the tool which I just did. I donāt really see any kind of binding and I have checked many times for looseness with none found but I can say that I seem to get a vibration during y movement as the enclosure makes a lot of noise. I always chalked that up to a big chunk of metal panel vibrating. I reinstalled cut control today and had to reset all my axis steps so I know they are right on. I cut 2 parts and noticed the X&Y home was every bit of .100+" off but the Z wasnāt this time but prior the Z was so low before I reinstalled cut control it took a huge chunk out of my vise before I noticed. I didnāt even think of it missing steps but after reading this I am beginning to wonder. I have had so many issues that I am really frustrated and I cant get Langmuir to answer a freaking thing.
Thanks for the input I will look for these items tomorrow.
you could also try taking lighter cuts and see if it still has that issue. I was using some feeds/speeds from their sheet and its way to aggressive and my machine would stall and loose steps. Had one part skip almost 1/4
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