Results 1 to 4 of 4

Thread: Getting extra life out of your Z pinion

  1. #1
    Join Date
    Mar 2008
    Location
    Radford VA
    Posts
    586

    Default Getting extra life out of your Z pinion

    I recently swapped out my non-geared Z motor for a 10:1 geared version. While doing all the calculations for my unit values, I ran across something that I never realized.

    Most all Shopbots have either a 20 tooth or 25 tooth pinion gear for Z. A 20 tooth pinion moves your Z rack 3.14 inches for every one revolution. A 25 tooth pinion moves your Z rack 3.92 inches for every one revolution. If you think about it, most people do 80% of their cutting over maybe a 2" range of Z travel. So, on a 25 tooth pinion, especially, you are wearing out only half the pinion.

    Every few months, I am going to disengage my Z motor from the rack and then rotate it half a turn. This should help wear all the pinion teeth equally. Possibly giving me 1.5 to 2 times the life of the pinion.

  2. #2
    Join Date
    Jan 2014
    Location
    highpoint NC
    Posts
    6

    Default noise?

    do your wearing pinions make odd whirring? or any other (hard to describe in text noises) mine are making some odd noises every once in awhile in the length of the track, other than just the sound of the electric drive motors.
    PRS alpha 120x60

  3. #3
    Join Date
    Mar 2008
    Location
    Radford VA
    Posts
    586

    Default

    Robert - Check your rack and pinion and be sure there are no wood and/or metal chips in the teeth. I once had a small sliver of metal come off a tooth that was causing some roughness in my Z axis. Didn't make a whirring noise, but had a rough spot that you could feel by hand.

    Also, make sure your setscrews are tight.
    PRT Alpha with 7.2 upgrade, indexer, and PC router

  4. #4
    Join Date
    Mar 2010
    Posts
    4

    Default zmotor

    Quote Originally Posted by blackhawk View Post
    Robert - Check your rack and pinion and be sure there are no wood and/or metal chips in the teeth. I once had a small sliver of metal come off a tooth that was causing some roughness in my Z axis. Didn't make a whirring noise, but had a rough spot that you could feel by hand.

    Also, make sure your setscrews are tight.
    How did you remove the z motor? I am trying to replace the pinion but i don't see a way to get the motor off without disassembling the whole z-car.

Similar Threads

  1. Coiled extra wire
    By Tom Bachman in forum ShopBotter Message Board
    Replies: 9
    Last Post: 10-26-2016, 09:14 AM
  2. Got some extra time on your hands?....
    By srwtlc in forum ShopBotter Message Board
    Replies: 1
    Last Post: 05-15-2016, 09:52 PM
  3. Looking for extra height
    By Rick W in forum Variations & Modifications of ShopBots
    Replies: 6
    Last Post: 01-27-2013, 09:35 PM
  4. Extra Z axis
    By benchmark in forum Archives2007
    Replies: 21
    Last Post: 11-05-2007, 07:27 AM
  5. Extra Z axis
    By jdhouse57@msn.com in forum Archives2003
    Replies: 3
    Last Post: 08-23-2003, 01:18 PM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •