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Question #: 871

Question: How do I keep the lead screw from moving back and forth?

Current Solution

The lead screw needs to be stabilized axially. The lead screw should turn, but not move any other way. The method to keep the lead screw stable is to use two bearings with ID (inside diameter) that match the diameter of the lead screw. The bearings are positioned before and after a stable structural part. A collar is positioned at one side of the bearing assembly and another collar, or end of a coupling is positioned at the other side of the bearing assembly.

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Other Possible Solutions to this Question

  • If using a grease how does one protect leadscrews and rails from corian dust etc.

    If you have abrasive particles in the air from milling, you will want to periodically clean the mechanical parts like the lead screw and anti-backlash nuts. After cleaning the parts, all of the high friction parts that will be in constant contact, lubricating the parts with oils, grease or other lubricants. If the part is of steel material, that material will definitely need to be oiled, greased or lubricated so minimal oxidation will affect the exterior of the steel parts.

    The anti-backlash nut is made of Delrin, so petroleum chemicals like oils, grease or lubricants are ok to use. Abrasive particles may affect the anti-backlash nut over time; however, the spring and bushing of the anti-backlash nut will provide extensive use regardless of the wear.

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    If using a grease how does one protect leadscrews and rails from corian dust etc.

  • how do you calibrate steps per inch using Mach3 and a 1/2x13 lead screw

    You will first need to derive the number of turns per inch that your lead screw produces. If there is only a single start (typical all thread screws), then the turns per inch is the same as TPI (threads per inch). If there is multiple starts, then the number of starts is divided by the TPI to determine the turns per inch. For example, 10 TPI with 5 starts is 10 / 5 = 2 turns per inch. Now that we know this, we can get the number of steps per inch as described in the previous question: take the number of steps per revolution that the motor will output. This will be the number of full steps that you motor produces (typically 200, or 1.8 degrees per step) multiplied by the microstepping per step to which the driver is configured. Simply multiple the number of turns per inch and the number of steps per revolution and you will get the steps per inch. Ok, lets see the formula:

    200 steps * 16 microsteps * 2 turns per inch = 6400 steps per inch


    Additional Information:
    14798


    Additional Information:
    hallo i have cnc with ball screw 2.5mm of pith..n driver stepping 1/16 how to setup step value

    Additional Information:
    i have ball screw with 2.5 mm of pith n 1 start motor 200 step 1/16 driver stepping

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    how do you calibrate steps per inch using Mach3 and a 1/2x13 lead screw

  • HOW DO I DETERMINE THE AMOUNT OF SCREW WEIGTH THAT MY MOTOR CAN HANDLE

    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

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    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

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    HOW DO I DETERMINE THE AMOUNT OF SCREW WEIGTH THAT MY MOTOR CAN HANDLE

  • THE LEAD SCREW IS VERY HARD TO TURN. BACKLASH BUSHING SEEMS BE TOO TIGHT AND BINDING ON SCREW. DO IT NEED LUBRICATION OR DID DAMAGE NUT WHEN INSERTING SCREW?

    Yes, you can use lubrication, like 3-in-1 oil to make it a bit easier. You will need to run it up and down to break it in.

    Additional Information:

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    THE LEAD SCREW IS VERY HARD TO TURN. BACKLASH BUSHING SEEMS BE TOO TIGHT AND BINDING ON SCREW. DO IT NEED LUBRICATION OR DID DAMAGE NUT WHEN INSERTING SCREW?

  • Are there contour type brushes available for leadscrews and round rails

    Yes, you can use these flexible strip brushes and create a mount for the contour that you need:

    https://www.buildyourcnc.com/item/strip-brush

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    Are there contour type brushes available for leadscrews and round rails

  • Do you make blackfoot with leadscrew for x and y axis?

    Currently we do not have any lead screw driven machines except our scratch build kit, all other models use either timing belt or are chain driven.

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    Do you make blackfoot with leadscrew for x and y axis?

  • Do you make blackfoot with leadscrew for x and y axis?

    Currently we do not have any lead screw driven machines except our scratch build kit, all other models use either timing belt or are chain driven.

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    Do you make blackfoot with leadscrew for x and y axis?

  • How do I order specific lengths of lead screws in one order?

    Just specify the full length in the quantity field in the shopping cart and give us a call to inform us of the cut lengths (you can also email customer service - link in the contact us page - link at the footer). We are working on a way to do this at the product page, but won't be finished for a few more days.

    Additional Information:
    20

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    How do I order specific lengths of lead screws in one order?

  • Can’t find info about all three lead screws in you book or how to secure them

    The details will differ depending on the type of lead screw you use.

    For allthread lead screws, you will need the 1/2" square nut, 1/2" allthread lead screw, two 1/4" screws and nuts to hold the square nut in place, two 1/2" ID bearings, two standard 1/2" nuts, and one coupling hub.

    Attach the square nut to the nut support using the two 1/4" screw and nuts. The bearings will need to be inserted into the seats of the lower and upper part of the z-axis. Insert the lead screw through the top bearing. Use one of the standard 1/2" nuts and start threading it on the allthread screw just below the bearing. Lower the lead screw to the square nut and start to screw the lead screw into the square nut. Continue until the screw is near the lower bearing. Add another standard 1/2" nut to the screw and keep turning the screw until the screw just passes the lower bearing. Add the coupling hub to the top of the screw just above the upper bearing. Turn the lower and upper standard 1/2" nuts until they are snug against the bearing. If the standard 1/2" nuts become loosened, consider adding another nut to each end against the existing nut to keep them in place.

    For 1/2" acme 5 start lead screws, you will need to use an antibacklash nut in place of the square nut. This nut attaches with a flange using two #8 screws and nuts. The standard 1/2" nuts are replaced by clamping collars.

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    Can’t find info about all three lead screws in you book or how to secure them

  • one of my motors from the blackfoot kit goes back and forth rather than turning, the wiring hasnt changed since i bought it, what could be wrong?

    The motor shaft does not turn, but slides back and forth in an axial motion? Please submit additional information on this page.

    Additional Information:
    it goes one step then the next step in the other direction so it seems to just vibrate

    Additional Information:
    It sounds like this could be a bad driver? You can determine if this is the cause by connecting another motor to this driver to see if it still happens to the new motor plugged into that driver. This will either rule out the motor causing this, or if it is the driver.

    You can also possibly rule out the driver as well if you change the step and direction wires from another driver to the problem driver.

    Make sure you do these steps one at a time. It's best to consider a single variable at a time.

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    one of my motors from the blackfoot kit goes back and forth rather than turning, the wiring hasnt changed since i bought it, what could be wrong?

  • Does the 5 start lead screw come with any nuts?

    Our 5 Start ACME screw is sold by the inch, and sold as a single product. No anti-backlash nuts are sold with the purchase of the ACME screw as the anti-backlash nut is sold separately.

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    Does the 5 start lead screw come with any nuts?

  • Hi! can i order a 6 ft long 1/2'' Lead screw with the motor and the gears with it?

    1/2" lead screw can be purchased in one length up to 77 inches (6 feet, 5 inches). Motors are found under the "Motion Electronics" menu, and gears can be found under "Mechanical Components".

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    Hi! can i order a 6 ft long 1/2'' Lead screw with the motor and the gears with it?

  • How do I order a pacific length of lead screw?

    Just specify the full length in the quantity field in the shopping cart and give us a call to inform us of the cut lengths (you can also email customer service - link in the contact us page - link at the footer). We are working on a way to do this at the product page, but won't be finished for a few more days.

    Additional Information:
    20

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    How do I order a pacific length of lead screw?

  • Will the 1/2" 5 start lead screw and the 3/8" 5 start will it all work together in unison

    If the turns per inch on a lead screw is different, then the nut on the lead screw will move at a different velocity.

    Additional Information:
    Let me explain in more detail.

    Let's say you have two lead screws:

    - 1/2" 5 starts at 10 TPI = 2 turns per inch. (5 starts / 10 TPI = 1/2 inches per turn or 10 TPI / 5 Starts = 2 turns per inch.)

    - 3/8" 2 starts at 10 TPI = 5 turns per inch. (2 starts / 10 TPI = 1/5 inches per turn or 10 TPI / 2 starts = 5 turns per inch.)


    So, if two stepper motors (one connected to the 1/2" lead screw and the other connected to the 3/8" lead screw) turned 10 revolutions in 2 seconds, the 1/2" lead nut would travel 5 inches and the 3/8" lead nut would travel 2 inches at the 2 second mark.

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    Will the 1/2" 5 start lead screw and the 3/8" 5 start will it all work together in unison

  • Will the 1/2" 5 start lead screw and the 3/8" 5 start will it all work together in unison

    If the turns per inch on a lead screw is different, then the nut on the lead screw will move at a different velocity.

    Additional Information:
    Let me explain in more detail.

    Let's say you have two lead screws:

    - 1/2" 5 starts at 10 TPI = 2 turns per inch. (5 starts / 10 TPI = 1/2 inches per turn or 10 TPI / 5 Starts = 2 turns per inch.)

    - 3/8" 2 starts at 10 TPI = 5 turns per inch. (2 starts / 10 TPI = 1/5 inches per turn or 10 TPI / 2 starts = 5 turns per inch.)


    So, if two stepper motors (one connected to the 1/2" lead screw and the other connected to the 3/8" lead screw) turned 10 revolutions in 2 seconds, the 1/2" lead nut would travel 5 inches and the 3/8" lead nut would travel 2 inches at the 2 second mark.

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    Will the 1/2" 5 start lead screw and the 3/8" 5 start will it all work together in unison

  • do you guys sell full set of lead screws, machined with bearings and mounts?

    We sell all of those parts and if you need the lead screw machined to a specific spec, we can do this. To provide the specs, please send an email to us from the contact us page, link located in the footer.

    If there is a specific part you need, please let us know and we can let you know if we have it, or if we can start carrying it.

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    do you guys sell full set of lead screws, machined with bearings and mounts?

  • how long are your lead screws 3/8 and how much ? looking for 3/8 see my previous question

    We currently only stock 2 start lead screw for the 3/8".

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    how long are your lead screws 3/8 and how much ? looking for 3/8 see my previous question

  • how long are your lead screws 3/8 and how much ? looking for 3/8 see my previous question what is the minimum length and how much per inch
  • If I buy the 1/2" 5 start lead screw and the 3/8" 5 start lead screws will it all work together

    If the turns per inch on a lead screw is different, then the nut on the lead screw will move at a different velocity.

    Additional Information:
    Let me explain in more detail.

    Let's say you have two lead screws:

    - 1/2" 5 starts at 10 TPI = 2 turns per inch. (5 starts / 10 TPI = 1/2 inches per turn or 10 TPI / 5 Starts = 2 turns per inch.)

    - 3/8" 2 starts at 10 TPI = 5 turns per inch. (2 starts / 10 TPI = 1/5 inches per turn or 10 TPI / 2 starts = 5 turns per inch.)


    So, if two stepper motors (one connected to the 1/2" lead screw and the other connected to the 3/8" lead screw) turned 10 revolutions in 2 seconds, the 1/2" lead nut would travel 5 inches and the 3/8" lead nut would travel 2 inches at the 2 second mark.

    Click the link to respond:
    If I buy the 1/2" 5 start lead screw and the 3/8" 5 start lead screws will it all work together