### Question #: 2361

Question:
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On the book build machine I changed the Z axis from a 13 tpi lead screw to an acme 10 tpi 5 start lead screw. What numbers do I put into the motor tuneing boxes.
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**The settings that will have to be change will be your steps per inch in motor tuning (mach 3), or settings/axes(planetCNC). But we do not have the actual numbers/specs that will fit your 10 TPI 5 start lead screw, here is a tutorial video which explains how to get the exact numbers you need! (**

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### Other Possible Solutions to this Question

**I just changed my X and Y to the ACME 1/2" 5 start lead screw. What are the motor tuning numbers. I have the book built machine.**The settings that will have to be change will be your steps per inch in motor tuning (mach 3), or settings/axes(planetCNC). But we do not have the actual numbers/specs that will fit your 10 TPI 5 start lead screw, here is a tutorial video which explains how to get the exact numbers you need! (

)**Click the link to add information to this solution:**

I just changed my X and Y to the ACME 1/2" 5 start lead screw. What are the motor tuning numbers. I have the book built machine.**On the Book Build: I'm changing the 13TPI 1/2" lead screw with the 1/2" 10 TPI Acme screw with the anti backlash nut. This is for the Z axis only. What should I know about installing it and what are the numbers I need to plug into the motor tuning area.**The settings that will have to be change will be your steps per inch in motor tuning (mach 3), or settings/axes(planetCNC). But we do not have the actual numbers/specs that will fit your 10 TPI 5 start lead screw, here is a tutorial video which explains how to get the exact numbers you need! (

).

Here is a default setting that you might be able to tune and adjust accordingly: 1600 steps, accel 400.02, velocity 5.**Click the link to add information to this solution:**

On the Book Build: I'm changing the 13TPI 1/2" lead screw with the 1/2" 10 TPI Acme screw with the anti backlash nut. This is for the Z axis only. What should I know about installing it and what are the numbers I need to plug into the motor tuning area.**Since I am using normal all-thread lead screw 13 TPI 1/2" for the book build cnc, what can be the maximum feed rate of machine and how can I change the mechanical setup in mach 3? I am using 1/4" steel carbile endmill with 2 flutes and router is 2 HP with variable speed**Book build (scratch build), feedrates and recommendation.

Using standard allthread will provide around 20-30 ipm using 36 volts. Although it allows for a working CNC machine, the RPM of the spindle/router will need to spin at the lowest setting to provide the beat efficiency and life for the end mill at 1/4" cut diameter and higher. The speeds may be fine for smaller end mills.

If you would like faster speeds, you should change the lead screws on the CNC machine to the 1/2" 5 start 10 TPI which translates to 2 turns per inch which means, the stepping motor will not need to turn as fast to produce faster motion. That is to say, the stepping motor will only need to turn two revolutions for the machine to travel one inch and with the allthread, the stepping motor will need to turn 13 times to reach one inch.

Link to the lead screw and other mechanical parts needed:

https://www.buildyourcnc.com/CNCMachineMechanicalParts.aspx

To change the lead screws you will need (for each axis):

1. The lead screw for that axis.

2. Two 1/2" collars to keep the lead screw axially stable.

3. One Antibacklash nut.

Additional Information:

20**Click the link to add information to this solution:**

Since I am using normal all-thread lead screw 13 TPI 1/2" for the book build cnc, what can be the maximum feed rate of machine and how can I change the mechanical setup in mach 3? I am using 1/4" steel carbile endmill with 2 flutes and router is 2 HP with variable speed**How do I secure the non-motor end of the lead screw for my 'Book' machine build? Does it just sit inside the bearing or do i use a nut to lock it in place? I did not see any instructions for this in the book.**Use a clamping collar (if you are using an ACME lead screw) or a couple of 1/2 nuts (if using an allthread) against the bearing to keep the bearing in place and make sure there is no axial play.

**Click the link to add information to this solution:**

How do I secure the non-motor end of the lead screw for my 'Book' machine build? Does it just sit inside the bearing or do i use a nut to lock it in place? I did not see any instructions for this in the book.**What are the toggle switch settings on the stepper motor drivers for the .5 in. lead screw 10 tpi 2 turns per inch? Thankyou!**On the top of the stepper motor drivers is a grid with the appropriate toggle switch positions for the lead screw being used. If it is 2 turns per inch, the proper toggle switch positions would be 01101110. Try this and see if it works.

**Click the link to add information to this solution:**

What are the toggle switch settings on the stepper motor drivers for the .5 in. lead screw 10 tpi 2 turns per inch? Thankyou!**Regarding 1/2" 5 start and 10 TPI ACME precision lead screw, what the maximum length you can ship within USA? I'm looking for something like 100" and I could use a 1" screw if available. Please include estimated price. Thanks.**The maximum length we can ship is a total of 78" inches. However we can send your required length in portions. Please refer to adding the total items you require to your cart to get a visualized amount and shipping cost.

**Click the link to add information to this solution:**

Regarding 1/2" 5 start and 10 TPI ACME precision lead screw, what the maximum length you can ship within USA? I'm looking for something like 100" and I could use a 1" screw if available. Please include estimated price. Thanks.**I am planning to build a scratch CNC machine to do rotary engraving on writing pens. Can you recommend the parts I would need? I'm thinking NEMA 14 (11?) and 3/8" acme rod. Not sure which linear motion to use. I have an old lathe to use for the 4th axis.**Consider the loads on each axis when choosing appropriate stepper motors. If your holding torque is maxed out at roughly 16oz/in (1lb/in), then you could use the NEMA 11 or 14. Also consider the shaft sizes and current ratings when choosing drivers that pair with the motors.

**Click the link to add information to this solution:**

I am planning to build a scratch CNC machine to do rotary engraving on writing pens. Can you recommend the parts I would need? I'm thinking NEMA 14 (11?) and 3/8" acme rod. Not sure which linear motion to use. I have an old lathe to use for the 4th axis.**I need the calculation to determine the stepper motor torque to find the load that it can lift using a lead screw at 1/2" diameter with 13 TPI.**There are two main questions that we can answer with respect to motor torque and the mechanical advantage of lead screws, 1) What torque motor do you need to lift a particular weight, or 2) What maximum weight will my motor torque be able to lift.

This formula uses Newtons (N) as it's final unit. Use this with the included radius (R) to determine the torque. Newtons can easily be converted to lbs or ounces using online conversions.

Effort = Sf + (Load/(2 x pi x (R/p) x Se))

where:

p = pitch of the screw

Se = screw efficiency = Standard lead screw will be between 20% (.2) and 40% (.4)

Sf = static force. This is the force that is needed to start the movement. The number may be eliminated, but it is good to use a number in the 5 N to 20 N range.

Load = the expected load that the effort will need to carry (i.e., the router and the included axis assembly that the motor will need to lift)

R = radius of the lead screw

This formula is based on the "law of the machine"

The final effort amount with its unit of newtons and R will be the torque. For example, if the effort comes to 100 N (newtons) and the R is .5 inches, then you can assume that the effort is 50 N-in since it would take twice the effort to turn form the one inch mark from the center of the shaft.

Example:

Load = 90 N (20.2 lbs)

R = 1 inch since that is the length from the center of the shaft that the motor is rated

p = 1 inch / 13 = .08 inches

Effort = 5 N + (90 N / (2 x 3.14 x (1 / .08) x .2))

Effort = 5 N + (90 N / (6.28 x 12.5 x .2))

Effort = 5 N + (90 N / (15.7))

Effort = 5 N + (5.73 N)

Effort = 10.7 N = 2.4 lbs = 38.4 oz-in

I am putting the oz-in on the end because the formula considers the distance from the center of the shaft to be one inch.

Therefore, a 425 oz-in motor would be able to lift a 20.2 lb Router with its accompanying assembly. If the assembly and router is heavier, plug in the numbers and determine the effort required.

With a bit of algebra, the formula can be rewritten to find the load:

Load = (Effort - Sf) x (2 x pi x (R/p) x Se)

Another formula that does not consider friction at all:

Effort = (Load x p) / (2 x pi x R)

Lets see if we get similar results:

Effort = (20 lb x .08 inches) / (2 x 3.14 x 1)

Effort = 1.6 / 6.28 = .255 lbs = 4.08 oz-in

The results from both formulas appear to be very small because a 13 TPI screw will have enormous mechanical advantage.

It is evident that the first formula that does consider friction that we are loosely estimating is far more conservative than the second formula. Either way, even the most conservative formula shows that the 425 oz-in motor will handle very large weights. If you are using a lead screw with only two turns per inch, .5 inch pitch, you can determine the requirements with the first formula.

Example for a 10 TPI 5 start (2 turns per inch) lead screw:

Load = 90 N (20.2 lbs)

R = 1 inch since that is the length from the center of the shaft that the motor is rated

p = 1 inch / 2 = .5 inches

Effort = 5 N + (90 N / (2 x 3.14 x (1 / .5) x .2))

Effort = 5 N + (90 N / (6.28 x 2 x .2))

Effort = 5 N + (90 N / (2.512))

Effort = 5 N + (35.83 N)

Effort = 40.828 N = 9.18 lbs = 146.88 oz-in

Customer Response:

thank you so much

Additional Information:

Additional Information:

Additional Information:

how do i calculate torque of stepper motor if lead screw coupled to motor shaft and load applied by lead screw on plate is 100 kg by vertically

Additional Information:

Pls

Additional Information:

1m 16mmdiameter ball screws calculations**Click the link to add information to this solution:**

I need the calculation to determine the stepper motor torque to find the load that it can lift using a lead screw at 1/2" diameter with 13 TPI.**I have a lead screw machine I built from the book plans (i know, ancient history) and I'm thinking of converting the X and Y axis to rollerchain. Assuming I can configure my controller appropriately, is there anything I should buy besides chain, drive cog, tension cog and mounting hardware?**You want to make sure that the motors will be able to provide the necessary torque since there will not be mechanical advantage using roller chain. You will need a way to fix the chain to each end. I like to use #4 - 3/4" screws and #4 nuts. You will need a drive sprocket for each axis and a couple idler sprockets on each axis to serve as tensioners and guiding the roller chain.

Additional Information:

OK cool. I have NEMA 24 steppers rated 425 oz-in. Is there some rule of thumb I can use to guess if that's enough? I'm not planning to push against hard stock material.**Click the link to add information to this solution:**

I have a lead screw machine I built from the book plans (i know, ancient history) and I'm thinking of converting the X and Y axis to rollerchain. Assuming I can configure my controller appropriately, is there anything I should buy besides chain, drive cog, tension cog and mounting hardware?**Has anyone built the machine from the book plans and made substitutions for the store-bought threaded rod? I wanted to spend a bit more money to ensure smoother/faster/more accurate travel with the lead screws, but i am not sure what to use. Mcmaster Carr has quite a few Acme lead screw options, however the price varies drastically. Any input is appreciated.**You can use any type of threaded rod, i.e. ACME profile, hi-lead, ball screw, etc. The only change you will need to make is the way the lead nut fastens to the nut mount on the machine. Lead nuts for these non-allthread screws typically have flanges with mounting holes, so the mounting of this type of nut is far better than the standard nut used in the book build.

These better screw options will also allow your machine to move faster and with less backlash.

https://buildyourcnc.com/item/mechanical-leadscrews-antibacklash-nut-!5-5-starts-10-tpi

https://buildyourcnc.com/item/mechanical-leadscrews-lead-screw-!5-5-starts-10-tpi**Click the link to add information to this solution:**

Has anyone built the machine from the book plans and made substitutions for the store-bought threaded rod? I wanted to spend a bit more money to ensure smoother/faster/more accurate travel with the lead screws, but i am not sure what to use. Mcmaster Carr has quite a few Acme lead screw options, however the price varies drastically. Any input is appreciated.**What tolerance can I expect from your largest cnc machine and the laser cutter? Also, what depth can I get on the z axis?**The largest CNC machine we make at this time (12/04/2015) is the GreenBull 6'x12' model. This model has 2 options for Z-axis travel.

The short-z option has a total Z travel of 5.75 inches. From that you would subtract the length of the end mill used and the thickness of the spoil board to determine the maximum material thickness. (Example: If the end mill extends 1.25" from the collet and the spoil board is .75", then the material could be up to 5.75 - 1.25 - 0.75 = 3.75 inches in thickness). This is good for most sheet-type materials.

The long-z option, used mainly for large 3D carvings, requires a custom frame and allows for up to 36" of travel.

The tolerance of our machines, like any machine, depends on several variables. The major variables include the manufacturing tolerance, the type of machine control used, the precision of assembly, the thoroughness of maintenance, and the initial and ongoing calibration of the machine. Because we sell kits only most of these variables are outside our control. Therefore, we are hesitant to guarantee a certain level of tolerance for an end user. However, in our experience, tolerances of .001" are readily achievable with our machines.**Click the link to add information to this solution:**

What tolerance can I expect from your largest cnc machine and the laser cutter? Also, what depth can I get on the z axis?**thank you for the reply. I would be really good to know the calculation. The lead screw is 1/2" diameter with 13 TPI. Please provide the calculation for determing the maximum weight motor can handle on Z-axis on book build cnc. And one more question. If I am cutting 18mm MDF with 6mm cutting bit (so 6mm pass), what can be the maximum speed rate of cutting and spindle speed of router? thank you**There are two main questions that we can answer with respect to motor torque and the mechanical advantage of lead screws, 1) What torque motor do you need to lift a particular weight, or 2) What maximum weight will my motor torque be able to lift.

This formula uses Newtons (N) as it's final unit. Use this with the included radius (R) to determine the torque. Newtons can easily be converted to lbs or ounces using online conversions.

Effort = Sf + (Load/(2 x pi x (R/p) x Se))

where:

p = pitch of the screw

Se = screw efficiency = Standard lead screw will be between 20% (.2) and 40% (.4)

Sf = static force. This is the force that is needed to start the movement. The number may be eliminated, but it is good to use a number in the 5 N to 20 N range.

Load = the expected load that the effort will need to carry (i.e., the router and the included axis assembly that the motor will need to lift)

R = radius of the lead screw

This formula is based on the "law of the machine"

The final effort amount with its unit of newtons and R will be the torque. For example, if the effort comes to 100 N (newtons) and the R is .5 inches, then you can assume that the effort is 50 N-in since it would take twice the effort to turn form the one inch mark from the center of the shaft.

Example:

Load = 90 N (20.2 lbs)

R = 1 inch since that is the length from the center of the shaft that the motor is rated

p = 1 inch / 13 = .08 inches

Effort = 5 N + (90 N / (2 x 3.14 x (1 / .08) x .2))

Effort = 5 N + (90 N / (6.28 x 12.5 x .2))

Effort = 5 N + (90 N / (15.7))

Effort = 5 N + (5.73 N)

Effort = 10.7 N = 2.4 lbs = 38.4 oz-in

I am putting the oz-in on the end because the formula considers the distance from the center of the shaft to be one inch.

Therefore, a 425 oz-in motor would be able to lift a 20.2 lb Router with its accompanying assembly. If the assembly and router is heavier, plug in the numbers and determine the effort required.

With a bit of algebra, the formula can be rewritten to find the load:

Load = (Effort - Sf) x (2 x pi x (R/p) x Se)

Another formula that does not consider friction at all:

Effort = (Load x p) / (2 x pi x R)

Lets see if we get similar results:

Effort = (20 lb x .08 inches) / (2 x 3.14 x 1)

Effort = 1.6 / 6.28 = .255 lbs = 4.08 oz-in

The results from both formulas appear to be very small because a 13 TPI screw will have enormous mechanical advantage.

It is evident that the first formula that does consider friction that we are loosely estimating is far more conservative than the second formula. Either way, even the most conservative formula shows that the 425 oz-in motor will handle very large weights. If you are using a lead screw with only two turns per inch, .5 inch pitch, you can determine the requirements with the first formula.

Example for a 10 TPI 5 start (2 turns per inch) lead screw:

Load = 90 N (20.2 lbs)

R = 1 inch since that is the length from the center of the shaft that the motor is rated

p = 1 inch / 2 = .5 inches

Effort = 5 N + (90 N / (2 x 3.14 x (1 / .5) x .2))

Effort = 5 N + (90 N / (6.28 x 2 x .2))

Effort = 5 N + (90 N / (2.512))

Effort = 5 N + (35.83 N)

Effort = 40.828 N = 9.18 lbs = 146.88 oz-in

Customer Response:

thank you so much

Additional Information:

Additional Information:

Additional Information:

how do i calculate torque of stepper motor if lead screw coupled to motor shaft and load applied by lead screw on plate is 100 kg by vertically

Additional Information:

Pls

Additional Information:

1m 16mmdiameter ball screws calculations**Click the link to add information to this solution:**

thank you for the reply. I would be really good to know the calculation. The lead screw is 1/2" diameter with 13 TPI. Please provide the calculation for determing the maximum weight motor can handle on Z-axis on book build cnc. And one more question. If I am cutting 18mm MDF with 6mm cutting bit (so 6mm pass), what can be the maximum speed rate of cutting and spindle speed of router? thank you**Just bought Build Your own CNC Machine book. It is missing the chapter on lead screws that is described on page 181 at the end of Chaprer 16. Where can I get this info?**It sounds like you got a misprinted book. If you purchased it from us, please contact us directly for a replacement. If you bought it from Amazon or a third party, you'll need to contact them. General information about lead screws is available on this website and at buildyourtools.com.

**Click the link to add information to this solution:**

Just bought Build Your own CNC Machine book. It is missing the chapter on lead screws that is described on page 181 at the end of Chaprer 16. Where can I get this info?**I need the calculation to determine the stepper motor torque to find the load that it can withstand in horizontal position using a lead screw at 1/2" diameter with 13 TPI.**There are two main questions that we can answer with respect to motor torque and the mechanical advantage of lead screws, 1) What torque motor do you need to lift a particular weight, or 2) What maximum weight will my motor torque be able to lift.

This formula uses Newtons (N) as it's final unit. Use this with the included radius (R) to determine the torque. Newtons can easily be converted to lbs or ounces using online conversions.

Effort = Sf + (Load/(2 x pi x (R/p) x Se))

where:

p = pitch of the screw

Se = screw efficiency = Standard lead screw will be between 20% (.2) and 40% (.4)

Sf = static force. This is the force that is needed to start the movement. The number may be eliminated, but it is good to use a number in the 5 N to 20 N range.

Load = the expected load that the effort will need to carry (i.e., the router and the included axis assembly that the motor will need to lift)

R = radius of the lead screw

This formula is based on the "law of the machine"

The final effort amount with its unit of newtons and R will be the torque. For example, if the effort comes to 100 N (newtons) and the R is .5 inches, then you can assume that the effort is 50 N-in since it would take twice the effort to turn form the one inch mark from the center of the shaft.

Example:

Load = 90 N (20.2 lbs)

R = 1 inch since that is the length from the center of the shaft that the motor is rated

p = 1 inch / 13 = .08 inches

Effort = 5 N + (90 N / (2 x 3.14 x (1 / .08) x .2))

Effort = 5 N + (90 N / (6.28 x 12.5 x .2))

Effort = 5 N + (90 N / (15.7))

Effort = 5 N + (5.73 N)

Effort = 10.7 N = 2.4 lbs = 38.4 oz-in

I am putting the oz-in on the end because the formula considers the distance from the center of the shaft to be one inch.

Therefore, a 425 oz-in motor would be able to lift a 20.2 lb Router with its accompanying assembly. If the assembly and router is heavier, plug in the numbers and determine the effort required.

With a bit of algebra, the formula can be rewritten to find the load:

Load = (Effort - Sf) x (2 x pi x (R/p) x Se)

Another formula that does not consider friction at all:

Effort = (Load x p) / (2 x pi x R)

Lets see if we get similar results:

Effort = (20 lb x .08 inches) / (2 x 3.14 x 1)

Effort = 1.6 / 6.28 = .255 lbs = 4.08 oz-in

The results from both formulas appear to be very small because a 13 TPI screw will have enormous mechanical advantage.

It is evident that the first formula that does consider friction that we are loosely estimating is far more conservative than the second formula. Either way, even the most conservative formula shows that the 425 oz-in motor will handle very large weights. If you are using a lead screw with only two turns per inch, .5 inch pitch, you can determine the requirements with the first formula.

Example for a 10 TPI 5 start (2 turns per inch) lead screw:

Load = 90 N (20.2 lbs)

R = 1 inch since that is the length from the center of the shaft that the motor is rated

p = 1 inch / 2 = .5 inches

Effort = 5 N + (90 N / (2 x 3.14 x (1 / .5) x .2))

Effort = 5 N + (90 N / (6.28 x 2 x .2))

Effort = 5 N + (90 N / (2.512))

Effort = 5 N + (35.83 N)

Effort = 40.828 N = 9.18 lbs = 146.88 oz-in

Customer Response:

thank you so much

Additional Information:

Additional Information:

Additional Information:

how do i calculate torque of stepper motor if lead screw coupled to motor shaft and load applied by lead screw on plate is 100 kg by vertically

Additional Information:

Pls

Additional Information:

1m 16mmdiameter ball screws calculations**Click the link to add information to this solution:**

I need the calculation to determine the stepper motor torque to find the load that it can withstand in horizontal position using a lead screw at 1/2" diameter with 13 TPI.**I received the electronics for book build cnc machine. I need to know how much weight the z-axis motor can hold since my (craftsman) router seems to be heavy. It is 2HP with variable speed**The motor is helped by the mechanical leverage of the screw. The 425 oz-in motors that are included in the standard electronics combo has very high torque for that type of machine. You will have no problem using that motor for the book machine.

We use that motor for very heavy spindles on the blackToe and blackFoot CNC Machine kits.

You will need to do the mechanical leverage calculation along with the torque of the motor to determine the actual weight it will lift. The calculation will need to consider the type and pitch of the screw and it would also consider the gravity constant of 9.8 m/s/s.

If you need me to determine this formula and work out the calculation based on the screw you are using, please let me know.

Additional Information:

thank you for the reply. I would be really good to know the calculation. The lead screw is 1/2" diameter with 13 TPI. Please provide the calculation. And one more question. If I am cutting 18mm MDF with 6mm cutting bit (so 6mm pass), what can be the maximum speed rate of cutting and spindle speed of router?

thank you**Click the link to add information to this solution:**

I received the electronics for book build cnc machine. I need to know how much weight the z-axis motor can hold since my (craftsman) router seems to be heavy. It is 2HP with variable speed**if i purchase the 4 Axis Electronic Combos and the Combo #1 with hardware, plans and DVD what else do i need to have a complete cnc machine**Other items you will need if you are purchasing the electronic combo (motors, drivers, power supply and computer interface) and the hardware and plans kit:

You will need the wood to create the structure of the machine. You will need a router to serve as the cutting instrument. You will need a computer to control the machine and the software that will serve as the control program. You will also need lead screws and rails (aluminum angles). If you intend to have faster travel than 20 ipm, we recommend purchasing the 5 start lead screws so you can achieve up to 300 ipm. https://www.buildyourcnc.com/item/mechanical-leadscrews-leadnuts-!5-5-starts-10-tpi**Click the link to add information to this solution:**

if i purchase the 4 Axis Electronic Combos and the Combo #1 with hardware, plans and DVD what else do i need to have a complete cnc machine**I am building your "Green Bull' 6 foot wide kit and I am at the stage of attaching the motor and drive chain. I would like to know if you have an modification kit available to put the 1/2" ACME screw on the Y-axis?**Currently we do not have that modification kit, our set up is fixed for our greenBull only modification kit we have for this model is the long z-axis kit(Designed for Foam cutting).

**Click the link to add information to this solution:**

I am building your "Green Bull' 6 foot wide kit and I am at the stage of attaching the motor and drive chain. I would like to know if you have an modification kit available to put the 1/2" ACME screw on the Y-axis?**I have the build your own CNC kit 3 Axis CNC Machine 2008, were can I get the Gcode or vector files for it ? I wanted to have it laser cut**Gcode or digital files are not available for our machines.

**Click the link to add information to this solution:**

I have the build your own CNC kit 3 Axis CNC Machine 2008, were can I get the Gcode or vector files for it ? I wanted to have it laser cut**I have an engine NEMA 34 from Y axis on my green bull that do not response, I already check connections and everything seems to be OK, how can I check that the motor it's working properly or not?**If one or more motor is not responding, please follow the troubleshooting directions below:

For parallel Bob only! Make sure both the parallel and USB are connected.

Re-check wiring, and connections for continuity (no breaks in the wires) and check for correct wiring locations from driver to BoB.

Check dip switch settings on the driver.

Check components, by swapping the motors (ex. y-axis motor to z or x-axis driver and z or x-axis motor to y-axis driver) to check if motor functions on another driver.

Depending on software check step low active (mach 3) or invert pulse (planet-cnc) for the axis which is not responding.

Mach 3 - config/port & pins/motor outputs / Planet-CNC - file/settings/axes**Click the link to add information to this solution:**

I have an engine NEMA 34 from Y axis on my green bull that do not response, I already check connections and everything seems to be OK, how can I check that the motor it's working properly or not?