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  • tool fan
    replied
    Originally posted by al.m.. View Post
    ​ It's alive.i salvaged the motor mount from the treadmill and mounted it on the lathe,worked very well,with the existing belt it's about 2/3 along the adjustment slots.temporarily mounted the electronics,I do have a proper enclosure coming,at $26 it's the single biggest expense in the conversion. It seams to have plenty of torque at very low speed,and runs quiet and smooth.i actually turned something!
    Sounds like you got it right. However, your pictures are not showing.

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  • al.m..
    replied
    ​ It's alive.i salvaged the motor mount from the treadmill and mounted it on the lathe,worked very well,with the existing belt it's about 2/3 along the adjustment slots.temporarily mounted the electronics,I do have a proper enclosure coming,at $26 it's the single biggest expense in the conversion. It seams to have plenty of torque at very low speed,and runs quiet and smooth.i actually turned something!
    Last edited by al.m..; 01-19-2020, 04:17 PM.

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  • beakie
    replied
    Originally posted by al.m.. View Post
    Gee Tom,are you referring to speed control on the slippery slope,or rpm on the lathe,lol
    Well you can't control one... and you're assembly the parts to control the other... enjoy both!

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  • al.m..
    replied
    Originally posted by beakie View Post
    The slippery slope has claimed another one!!

    Enjoy the speed control. As a complete rookie, even I appreciate the usefullness and safety of being about to change RPMs with such ease.
    Gee Tom,are you referring to speed control on the slippery slope,or rpm on the lathe,lol

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  • beakie
    replied
    The slippery slope has claimed another one!!

    Enjoy the speed control. As a complete rookie, even I appreciate the usefullness and safety of being about to change RPMs with such ease.

    Leave a comment:


  • al.m..
    replied
    Click image for larger version

Name:	image.jpeg
Views:	117
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ID:	1266815Click image for larger version  Name:	image.jpeg Views:	0 Size:	1.22 MB ID:	1266811Click image for larger version  Name:	image.jpeg Views:	0 Size:	1.40 MB ID:	1266810 Went to my brothers shop and used his tiny metal lathe .his largest chuck,a 4 jaw,wouldn't quite grab the outside of the flywheel,so chucked it by the pulley surface and turned the major o.d. so it would fit the 4 jaw,skimmed the faces while it was set up.Then grabbed it by the fresh major o.d in the four jaw,indicated it to get it spinning concentric,and turned down the pulley surface.I then chucked the 2-1/2" pulley I had and bored it to a light push got on the surface I machined on the flywheel.may file a flat for the set screw,or drill a dimple.
    just need a box for the electronics to complete this project.
    so far,$2.50 for cast pulley at Cardon,aprox $12.00 (including shipping)for 10 ohm potentiometer from amazon

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  • tool fan
    replied
    Originally posted by al.m.. View Post
    fan is cast into the flywheel,otherwise I would ditch it
    If you ditch the flywheel I think you’ll be disappointed.


    Sent from my iPhone using Tapatalk

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  • guylavoie
    replied
    Originally posted by iamtooler View Post

    This control does not react to slowing of motor, does it send continuous voltage rather than pulsed? How do you know if the motor is overloaded?
    Rob
    I haven't looked at the voltage applied to the motor with an oscilloscope to see if it's pulsed. I'm quite sure it must be doing something like that because the torque is still pretty good at low speeds, and the heat sinks on the board would need to be much bigger for something that would produce a high current, variable voltage.

    There is an overload indication (LED) on the board itself. Otherwise, you'd probably have to judge by how much it slows down if you're demanding too much.

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  • al.m..
    replied
    Originally posted by iamtooler View Post
    I am a big fan of flywheels but I am not sure it is of any use in this application, just a larger start torque requirement as there is a fair mount of rotating mass with a wood lathe.
    Rob
    fan is cast into the flywheel,otherwise I would ditch it

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  • tool fan
    replied
    You may be correct but my sense is that it helps maintain momentum.

    If you remove the flywheel another problem arises. Most treadmill motor armatures are not a standard 5/8”. Many are 41:64”. So it becomes necessary to either bore out a pulley or turn down the armature. In the end I have found it simpler to turn down the belt drive to 3/4”.


    Sent from my iPhone using Tapatalk

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  • iamtooler
    replied
    Originally posted by guylavoie View Post
    Well if it's like the controller board I had on the treadmill (DCMD57) it would be possible to use it with nothing more than two pushbuttons (each one between an input and common) to increase or decrease the speed, but if you have to press it 25 or 30 times each time you turn the lathe back on to get it up to speed, that would get old real quick. A straight DC motor control is much easier.

    I got this one:

    https://www.ebay.com/itm/AC-110V-220...IAAOSwlTBdkUGj
    This control does not react to slowing of motor, does it send continuous voltage rather than pulsed? How do you know if the motor is overloaded?
    Rob

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  • iamtooler
    replied
    I am a big fan of flywheels but I am not sure it is of any use in this application, just a larger start torque requirement as there is a fair mount of rotating mass with a wood lathe.
    Rob

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  • tool fan
    replied
    The flywheel helps maintain momentum and improves functionality of the motor. Some have fans built in and do help cool the motor. I machine the belt drive end down to 3/4” diameter and use the stub to attach a step pulley. The step pulley is not a requirement but useful to generate high speeds. If you try to get it 5/8” diameter it is sometimes too small and the stub breaks. Also check how the flywheel is secured. Most are held on with a left hand thread. If that is what you have you should ensure that it can not spin off I use a set screw to hold it in place. Hope this helps


    Sent from my iPhone using Tapatalk

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  • al.m..
    replied
    Originally posted by tool fan View Post
    I was wondering what controller you were referring to. I tried one of those and while it worked better than the smaller dc 51 controllers the MC 60 from an old treadmill was superior in terms of delivering low speed torque


    Sent from my iPhone using Tapatalk
    im going to start with the mc-60 and swe how it works out.
    while I have your attention,I have a couple ideas about pulleys,going to take some machining ( my brother has a small metal lathe.)
    what have you done?did you keep the the flywheel? I'm thinking it is needed for cooling

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  • tool fan
    replied
    I was wondering what controller you were referring to. I tried one of those and while it worked better than the smaller dc 51 controllers the MC 60 from an old treadmill was superior in terms of delivering low speed torque


    Sent from my iPhone using Tapatalk

    Leave a comment:

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