Hello,
while my nemas came with an 10mm axis, i had to buy another set of pulleys who have 32GT2-B10 instead of the 20GT-B6.35. So now my question is, where do i have to adjust this. Right now my acxis are moving around 15mm instead of the 10mm
Georg
motor polleys with more teeth
Re: motor polleys with more teeth
You have to send a command to GRBL (using the keyboard on the PC of a file stored on the SD card) in order to change the steps/mm parameter.
The commands looks like $xx=yyy.
See doc of GRBL here:
https://github.com/gnea/grbl/wiki/Grbl- ... figuration
The commands looks like $xx=yyy.
See doc of GRBL here:
https://github.com/gnea/grbl/wiki/Grbl- ... figuration
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- Messages : 68
- Enregistré le : 03 déc. 2020 11:42
Re: motor polleys with more teeth
Hello,
are these changes then permanently?
Georg
are these changes then permanently?
Georg
Re: motor polleys with more teeth
Yes
Mes imprimantes 3D:
Ender 3 Pro
Voron 2.4 (350X350mm)
...I3RS32 en cours...
RS-CNC 32 finie! (1mX1m)
Ender 3 Pro
Voron 2.4 (350X350mm)
...I3RS32 en cours...
RS-CNC 32 finie! (1mX1m)
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- Messages : 68
- Enregistré le : 03 déc. 2020 11:42
Re: motor polleys with more teeth
Hello,
i found the formula for $100 (currently set to 60.000)
STEPS_PER_REV = 200.0 //from config.h
MM_PER_REV = ??
MICROSTEPS = 2 //from config.h
X_STEPS_PER_MM = STEPS_PER_REV*MICROSTEPS/MM_PER_REV
the original pulley was with 20T, diameter 12.2mm, with a circumference of 40mm
my new pulley is 32T, diameter 19,8mm and circumference of 64mm
means mm_per_rev the 40 (old) or 64(new) mm
or do i have to use here another formula to get this?
equally what i put in the formula above its not matching the current result of 60.0
Georg
i found the formula for $100 (currently set to 60.000)
STEPS_PER_REV = 200.0 //from config.h
MM_PER_REV = ??
MICROSTEPS = 2 //from config.h
X_STEPS_PER_MM = STEPS_PER_REV*MICROSTEPS/MM_PER_REV
the original pulley was with 20T, diameter 12.2mm, with a circumference of 40mm
my new pulley is 32T, diameter 19,8mm and circumference of 64mm
means mm_per_rev the 40 (old) or 64(new) mm
or do i have to use here another formula to get this?
equally what i put in the formula above its not matching the current result of 60.0
Georg
Re: motor polleys with more teeth
Do not look at the diameter.
GT2 means 2 mm/teeth
So when 20T on the long loop => 20*2 = 40mm /tour (for 200 steps). There is a reduction with 2 pulleys 20/60: so 200 steps = 40mm*20/60 => step/mm = 200/(40*20) *60 =15step/mm.
Still when you use 4 microsteps (set up in the driver and not on the config) then GRBL has to generates more "steps" for the distance. So with 4 microsteps, $100 must be 15 * 4 = 60
You can easily recalculate with your pulleys and microsteps
GT2 means 2 mm/teeth
So when 20T on the long loop => 20*2 = 40mm /tour (for 200 steps). There is a reduction with 2 pulleys 20/60: so 200 steps = 40mm*20/60 => step/mm = 200/(40*20) *60 =15step/mm.
Still when you use 4 microsteps (set up in the driver and not on the config) then GRBL has to generates more "steps" for the distance. So with 4 microsteps, $100 must be 15 * 4 = 60
You can easily recalculate with your pulleys and microsteps
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- Messages : 68
- Enregistré le : 03 déc. 2020 11:42
Re: motor polleys with more teeth
Hello,
on german i would say "ich steh auf dem Schlauch" - i feel like a dummie
so from where is the 20 in this part, the 40 is form the previous calculation:
There is a reduction with 2 pulleys 20/60: so 200 steps = 40mm*20/60 => step/mm = 200/(40*20) *60 =15step/mm.
the 40 is from the first calculation with 20T, this will be 64 with my new pulley, or comes this also from the 20T and i have to exchange with 32 - or is this from the 20T pulley on the other end where the belt is turning?
200 steps = 64mm*32/60 => step/mm = 200/(64*32) *60 = 5,85step/mm.
or
200 steps = 64mm*20/60 => step/mm = 200/(64*20) *60 = 9,5step/mm.
and how do i calculate the z-axis with the spindle?
Georg
on german i would say "ich steh auf dem Schlauch" - i feel like a dummie
so from where is the 20 in this part, the 40 is form the previous calculation:
There is a reduction with 2 pulleys 20/60: so 200 steps = 40mm*20/60 => step/mm = 200/(40*20) *60 =15step/mm.
the 40 is from the first calculation with 20T, this will be 64 with my new pulley, or comes this also from the 20T and i have to exchange with 32 - or is this from the 20T pulley on the other end where the belt is turning?
200 steps = 64mm*32/60 => step/mm = 200/(64*32) *60 = 5,85step/mm.
or
200 steps = 64mm*20/60 => step/mm = 200/(64*20) *60 = 9,5step/mm.
and how do i calculate the z-axis with the spindle?
Georg
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- Messages : 68
- Enregistré le : 03 déc. 2020 11:42
Re: motor polleys with more teeth
Hello,
thanks for the help, the x and y axis are now working correct.
now i only need to adjust the z axis, is there also a formula for the threaded rod pitch 2mm, lead 2mm
Georg
thanks for the help, the x and y axis are now working correct.
now i only need to adjust the z axis, is there also a formula for the threaded rod pitch 2mm, lead 2mm
Georg