Machsupport Forum
Mach Discussion => General Mach Discussion => Topic started by: elgammmmal on May 05, 2009, 12:53:01 PM
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I've read tuning motor chapter,and make my calculation as below
pitch=1/5 =0.2 effective pitch =0.2x2=0.4
screw revs per unit =1/0.4 =2.5
motor revs per unit= 2.5xNs/Nm=2.5x1 =2.5 (1:1 drive ratio because my gear has no teeth)
mach3 steps per motor revs =200x32 = 6400
mach3 step per unit = 6400x2.5 =16000
would you please check this calculation if it right and if drive ratio 1:1 is right or not.
thank you for your support
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mach3 steps per motor revs =200x32 = 6400
You have a 32 microstep drive?
You also have a very low drive ratio which will give you very little torque. You are essentially direct driving a low pitch lead screw.
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Hi elgammmmal,
Are you working in mm or inches here.
Tweakie.
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hi Tweakie
thank you for your interest and my machine set up in mm .
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screw revs per unit =1/0.4 =2.5
You are working in mm and it takes 2.5 revolutions of your screw to go 1mm? Is that correct?
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pitch=1/5 =0.2 effective pitch =0.2x2=0.4
My guess is a 5 TPI double cut thread. 0.2" pitch, 0.4" lead.
screw revs per unit =1/0.4 =2.5
2.5 turns per inch
motor revs per unit= 2.5xNs/Nm=2.5x1 =2.5 (1:1 drive ratio because my gear has no teeth)
Assuming 1:1..........Don't understand "Toothless Gear".
mach3 steps per motor revs =200x32 = 6400
32 microstep
mach3 step per unit = 6400x2.5 =16000
Looks right to me but the units look to be INCHES
RC
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pitch=1/5 =0.2 effective pitch =0.2x2=0.4
My guess is a 5 TPI double cut thread. 0.2" pitch, 0.4" lead.
My guess is 5mm = .2" approx twinstart = 8mm .4" approx
mach3 steps per motor revs =200x32 = 6400
32 microstep
6400/8 = 800 steps
Phil
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motor revs per unit= 2.5xNs/Nm=2.5x1 =2.5 (1:1 drive ratio because my gear has no teeth)
Assuming 1:1..........Don't understand "Toothless Gear"..in mach 3 guide says (if the motor has a gear ,chain or belt drive to the screw with Nm teeth on the motor gear and Ns teeth on the screw gear then motor revs per unit = screw revs per unit xNs/Nm).my motor has gear with belt drive to the screw the gear is flat with no teeth so how can I calculate Nm and Ns.shall I ignore Nm and Ns in my calculation or there is anther way to calculated.
thank your for kind support
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Are you meaning you have pulleys and a belt but they are smooth with no cogs ?
That would be odd for an axis drive train.
If so... measure the OD of each pulley. Then divide the driven pulley dia by the drive pulley dia. That will be the ratio.
If they are the same OD it will be 1:1.
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If they are timing pulleys, just count the teeth on each pulley. Then divide.
Is this the type you have ?
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I've attach a picture of the pulley I'm using hope that can be help
thank you
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Well all you need to do is measure the OD of the 2 pulleys then divide but that probably will not work well for accurate motion control.
What exactly are you building ?
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I'm building cnc router for woodworking and I did try to use timing pulley but it is not available in my town I'm form Egypt so if it important I may make an order by any on line store. sorry for my poor writing
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Your writing is really quite good.
I'm sure you would have been dissapointed if you had used the smooth pulleys.
Good luck to you and post some pictures of your machine when you get it together.
Regards,
RC