1. Do not share user accounts! Any account that is shared by another person will be blocked and closed. This means: we will close not only the account that is shared, but also the main account of the user who uses another person's account. We have the ability to detect account sharing, so please do not try to cheat the system. This action will take place on 04/18/2023. Read all forum rules.
    Dismiss Notice
  2. For downloading SimTools plugins you need a Download Package. Get it with virtual coins that you receive for forum activity or Buy Download Package - We have a zero Spam tolerance so read our forum rules first.

    Buy Now a Download Plan!
  3. Do not try to cheat our system and do not post an unnecessary amount of useless posts only to earn credits here. We have a zero spam tolerance policy and this will cause a ban of your user account. Otherwise we wish you a pleasant stay here! Read the forum rules
  4. We have a few rules which you need to read and accept before posting anything here! Following these rules will keep the forum clean and your stay pleasant. Do not follow these rules can lead to permanent exclusion from this website: Read the forum rules.
    Are you a company? Read our company rules
Shared accounts will be removed Plugin Downloads Zero spam policy Forum Rules

Pgsaw worm gear motor backlash

Discussion in 'DIY Motion Simulator Building Q&A / FAQ' started by Zed, Nov 28, 2017.

Page 1 of 3
  1. Zed

    Zed VR Simming w/Reverb Gold Contributor

    Joined:
    Apr 4, 2017
    Messages:
    1,044
    Location:
    USA
    Balance:
    5,834Coins
    Ratings:
    +1,043 / 4 / -0
    My Motion Simulator:
    2DOF, DC motor, JRK
    Has anyone had issues with the backlash in the pgsaw worm gear motors and fixed it?

    I know some go with a bit out of balance condition to help but I’m looking for something that actually takes out the travel.

    Is it just needing another thrust washer or so, or is it slop in the gears? Are there any aftermarket gear sets for them that minimize backlash?

    Thanks in advance for any leads...
    • Like Like x 1
    Zed, Nov 28, 2017
    #1
  2. noorbeast

    noorbeast VR Tassie Devil Staff Member Moderator Race Director

    Joined:
    Jul 13, 2014
    Messages:
    20,535
    Occupation:
    Innovative tech specialist for NGOs
    Location:
    St Helens, Tasmania, Australia
    Balance:
    145,034Coins
    Ratings:
    +10,776 / 52 / -2
    My Motion Simulator:
    3DOF, DC motor, JRK
    All worm gearboxes are going to have some backlash, linear actuators are an alternate and are more efficient.

    How much play do yours have?
    • Informative Informative x 1
    noorbeast, Nov 28, 2017
    #2
  3. Zed

    Zed VR Simming w/Reverb Gold Contributor

    Joined:
    Apr 4, 2017
    Messages:
    1,044
    Location:
    USA
    Balance:
    5,834Coins
    Ratings:
    +1,043 / 4 / -0
    My Motion Simulator:
    2DOF, DC motor, JRK
    It’s not much but I do get that clicking and can feel it in the frame just a little. It would be a production to switch for linear actuators.

    I can take the motors off, wiggle things, and see if the worm shaft has endplay to maybe see if they just need some more washers in there. I can’t help true backlash in the gears but if it’s the worm moving back and forth, I probably can reduce that some.

    It’s just that quest for smooth, quiet motion. :)
    • Agree Agree x 1
    Zed, Nov 28, 2017
    #3
  4. Brett Horton

    Brett Horton Active Member

    Joined:
    Aug 18, 2016
    Messages:
    310
    Occupation:
    Program Manager / Pilot
    Location:
    Tampa FL
    Balance:
    118Coins
    Ratings:
    +202 / 2 / -0
    My Motion Simulator:
    3DOF, DC motor, JRK, Motion platform
    Keep us posted, as I have some in mine as well and would like to reduce.
    Brett Horton, Nov 28, 2017
    #4
  5. noorbeast

    noorbeast VR Tassie Devil Staff Member Moderator Race Director

    Joined:
    Jul 13, 2014
    Messages:
    20,535
    Occupation:
    Innovative tech specialist for NGOs
    Location:
    St Helens, Tasmania, Australia
    Balance:
    145,034Coins
    Ratings:
    +10,776 / 52 / -2
    My Motion Simulator:
    3DOF, DC motor, JRK
    This is about average wormdrive backlash and the greater the lever CTC the more noticeable it will be:

    • Like Like x 1
    • Agree Agree x 1
    • Informative Informative x 1
    noorbeast, Nov 28, 2017
    #5
  6. PiaMan

    PiaMan Active Member

    Joined:
    Aug 2, 2015
    Messages:
    192
    Location:
    Saskatchewan, CANADA
    Balance:
    607Coins
    Ratings:
    +131 / 2 / -0
    My Motion Simulator:
    3DOF, DC motor, SCN5, Arduino
    Ya drives me crazy the clacking. But more importantly the lost fidelity compared to my SCN rig. Would love find a solution
    • Like Like x 2
    PiaMan, Nov 28, 2017
    #6
  7. Brett Horton

    Brett Horton Active Member

    Joined:
    Aug 18, 2016
    Messages:
    310
    Occupation:
    Program Manager / Pilot
    Location:
    Tampa FL
    Balance:
    118Coins
    Ratings:
    +202 / 2 / -0
    My Motion Simulator:
    3DOF, DC motor, JRK, Motion platform
    This is exactly why I asked for a "Better" motor replacement a few months ago for the PGSaw motors we currently run.
    Gearbox and motor that is. Mainly just higher quality.
    • Agree Agree x 3
    Brett Horton, Nov 28, 2017
    #7
  8. PiaMan

    PiaMan Active Member

    Joined:
    Aug 2, 2015
    Messages:
    192
    Location:
    Saskatchewan, CANADA
    Balance:
    607Coins
    Ratings:
    +131 / 2 / -0
    My Motion Simulator:
    3DOF, DC motor, SCN5, Arduino
    My backlash is about the same as in that video. The worm gear setup is great for power and showing off as it will throw me or my guest out of my seat if cranked up. The scn setup however provides much more immersion due to the fine detail that is reproduced. I would equate the fidelity difference as the difference between an osw wheel and a thrustmaster t300 set to similar strength. Both have forcefeedback but the osw really tells you whats going on.
    • Like Like x 2
    PiaMan, Nov 28, 2017
    #8
  9. Brett Horton

    Brett Horton Active Member

    Joined:
    Aug 18, 2016
    Messages:
    310
    Occupation:
    Program Manager / Pilot
    Location:
    Tampa FL
    Balance:
    118Coins
    Ratings:
    +202 / 2 / -0
    My Motion Simulator:
    3DOF, DC motor, JRK, Motion platform
    You using 5 or 6?
    Brett Horton, Nov 28, 2017
    #9
  10. PiaMan

    PiaMan Active Member

    Joined:
    Aug 2, 2015
    Messages:
    192
    Location:
    Saskatchewan, CANADA
    Balance:
    607Coins
    Ratings:
    +131 / 2 / -0
    My Motion Simulator:
    3DOF, DC motor, SCN5, Arduino
    Scn5 150mm. Im pretty light at about 150lbs. I dont share my scn system much with friends so cant comment on much heavier user response but the few who have tried it i dont see a difference. I spent enough on my main rig that i dont want to see anything fail because i shared it.
    • Like Like x 1
    PiaMan, Nov 28, 2017
    #10
  11. gSeat

    gSeat Member

    Joined:
    Oct 1, 2017
    Messages:
    107
    Location:
    usa
    Balance:
    910Coins
    Ratings:
    +48 / 1 / -0

    Side question - I bought worm gears because of the roughly $200 savings per axis.
    As a first time sim build I'll still be blown away right :) ?
    Looked into SCN 6 and came across "noise complaints..." that didn't deter the choice too much since will use oculus headset, it was more about price and it seemed like I could make a smaller base footprint.
    gSeat, Nov 28, 2017
    #11
  12. Brett Horton

    Brett Horton Active Member

    Joined:
    Aug 18, 2016
    Messages:
    310
    Occupation:
    Program Manager / Pilot
    Location:
    Tampa FL
    Balance:
    118Coins
    Ratings:
    +202 / 2 / -0
    My Motion Simulator:
    3DOF, DC motor, JRK, Motion platform
    You will be amazed....
    • Like Like x 1
    • Agree Agree x 1
    Brett Horton, Nov 28, 2017
    #12
  13. Brett Horton

    Brett Horton Active Member

    Joined:
    Aug 18, 2016
    Messages:
    310
    Occupation:
    Program Manager / Pilot
    Location:
    Tampa FL
    Balance:
    118Coins
    Ratings:
    +202 / 2 / -0
    My Motion Simulator:
    3DOF, DC motor, JRK, Motion platform
    Very good resolution IMO, these are 25:1

    • Like Like x 1
    Brett Horton, Nov 28, 2017
    #13
  14. Zed

    Zed VR Simming w/Reverb Gold Contributor

    Joined:
    Apr 4, 2017
    Messages:
    1,044
    Location:
    USA
    Balance:
    5,834Coins
    Ratings:
    +1,043 / 4 / -0
    My Motion Simulator:
    2DOF, DC motor, JRK
    Yep - that's what I have too. Thanks! I can't pull a motor tonight to check end play but will. I'm hoping that's where the backlash is coming from since that would be an easy fix - just throw in some washers to minimize it.
    Zed, Nov 29, 2017
    #14
  15. noorbeast

    noorbeast VR Tassie Devil Staff Member Moderator Race Director

    Joined:
    Jul 13, 2014
    Messages:
    20,535
    Occupation:
    Innovative tech specialist for NGOs
    Location:
    St Helens, Tasmania, Australia
    Balance:
    145,034Coins
    Ratings:
    +10,776 / 52 / -2
    My Motion Simulator:
    3DOF, DC motor, JRK
    The average backlash is there by design for lubrication purposes, there is not much to fix unless it is outside design parameters.

    You could try a smaller lever CTC, you will loose some speed, gain some torque and reduce how noticeable the backlash is. A small amount of pre-load weight rather than perfect rig balance will also help reduce how noticeable the backlash is.
    • Informative Informative x 2
    • Agree Agree x 1
    Last edited: Nov 29, 2017
    noorbeast, Nov 29, 2017
    #15
  16. Zed

    Zed VR Simming w/Reverb Gold Contributor

    Joined:
    Apr 4, 2017
    Messages:
    1,044
    Location:
    USA
    Balance:
    5,834Coins
    Ratings:
    +1,043 / 4 / -0
    My Motion Simulator:
    2DOF, DC motor, JRK
    Well rats. I may still see about shimming end play on the worm if there is any even at the expense of lubrication. Or, worst case I start mulling over different actuators. I would like to get rid of the clicking.
    Zed, Nov 29, 2017
    #16
  17. Limongi

    Limongi Member

    Joined:
    Feb 14, 2017
    Messages:
    66
    Location:
    Vancouver, Canada
    Balance:
    - 7Coins
    Ratings:
    +57 / 0 / -0
    I'm trying to figure out a 3D printed surround for the pgsaw motor to isolate the clickity clacking. I'm thinking of a simple layering of ABS and rubber would at least be able to cut the noise in half if done well.

    This does nothing for backlash physically, but if you wanted to do that, the large spur gear needs to be replaced with a split spur gear. I would assume this modification would have a great deal of extra friction and as such the additional mechanical loss may not be worth it but I wouldn't know. I would also guess a split gear would be very high wearing to the worm gear in setups like ours. If someone has experience and the right mill it would be worth it but if not a DIY endeavour a machine shop would likely charge more per hour than the pgsaw motor costs in the first place.

    If I make a silencer that works I'll post a thread.

    Attached Files:

    • Creative Creative x 1
    Limongi, Dec 1, 2017
    #17
  18. Limongi

    Limongi Member

    Joined:
    Feb 14, 2017
    Messages:
    66
    Location:
    Vancouver, Canada
    Balance:
    - 7Coins
    Ratings:
    +57 / 0 / -0
    • Like Like x 1
    • Informative Informative x 1
    Limongi, Dec 2, 2017
    #18
  19. adgun

    adgun Active Member

    Joined:
    Jan 28, 2008
    Messages:
    493
    Occupation:
    mechanic
    Location:
    Netherlands
    Balance:
    5,541Coins
    Ratings:
    +131 / 3 / -0
    You need a wormwheel not a spurgear
    just my 2 cents
    • Informative Informative x 1
    adgun, Dec 2, 2017
    #19
  20. Limongi

    Limongi Member

    Joined:
    Feb 14, 2017
    Messages:
    66
    Location:
    Vancouver, Canada
    Balance:
    - 7Coins
    Ratings:
    +57 / 0 / -0
    • Useful Useful x 1
    Limongi, Dec 2, 2017
    #20
Page 1 of 3