Hey guys,
I am currently designing my third 3rd 3D printer - after having owned a Powerwas Evo and now printing on a prusa i3 aluminum -
i want both - something bigger and something more rigid.
it is going to be a machine with a frame consisting of Aluminum Extrusion Profiles in either 30x30 or 40x40mm - depended on the size and several calculations and of course motor-decisions - which i plan to
base upon reply to this thread.
Currently my i3 uses m5 - 0.8mm per turn for Z-Axis, and GT2 pulleys with 2 teeth on x and Y-axis.
While th z-axis i sobviously extreeemly slow (I can`t test the real speed, since the m5 threaded rod wasn`t made for linear movement and therefore has a lot of the motor`s torque eaten up by the movement alone and the friction the darn m5 nut is eating up.
With the X and Y-Axis I see them being 20 teeth - 2mms apart - coming out towards 40mm per rotation.
So for 40mm/s the motor would have to have 40rpm and so on.
being 1/16 micro stepping - it requires 3200 Steps per Rotation - ergo 40mm, which equals out to 80 steps per milimeter - which is nice, since it is 1) evenly dividable 2) quite a good resolution while maintaining enough speed.
which the controller should be easily up to.
I have seen videos of people driving their axis with more then 200mm/s
so let us assume, even 5x my speed with same configuration (currently RAMPS 1.4 - Mega 2560) is still doable.
That would be 5x 3200steps per second - coming towards 16000 Pulses per second.
but if I used 1/128 microstepping - which is 8x as much, as I am using now -
i am sure, the RAMPS 1.4 could not hold up.
This would need 128.000 Pulses/s to the motors.
but since I plan on using either ballscrews or trapezoidal leadscrews at about 5mm slope (is that a good value?!) that would come out at even 8 times less movement per full rotation of the stepper motor....
So I would or could easily need the motor do to 1600rpm...
I think I read somewhere the motors hard-limits for nema 17 or nema 23 sized motors is somwhere between 3500-4500rpms - so still room ahead.
but would the controller (RADDS Board) be fast enough to do 1.024.000 pulses/s ?!
I highly doubt it... what is the "hard-limit" here?
100khz? 400khz? Is there such a limit?
How are huge CNC machines moving so fast - are they relying solely on the PC´s processing power - certainly not huh?!
As I am opting for both - an increase in microstepping (at least 1/64 maybe even 1/128 microstepping) for ultrasmooth linear motion - see this link:
[www.dr-henschke.de]
and this Video: [www.youtube.com]
where He tests different stepper drivers and finds out, only the ones with 1764 or 1/128 microstepping are allowing for a really smooth movement of slow moves and that Decay musst be selectable via a trim-poti.
- I am unsure about which speeds I will be able to reach!
I am not sure that with the size of printer i am planning (bed 30x40cm) and it`s inherent need for rigidity and thus weight, nema 17 motors will be enough, I might go for Nema 23, also when doing 1/128 microstepping I am afraid I will not be able to reach higher speeds aany more - even with a RADDS Board and it`s faster processor.
With a GT2 pulley system it would be surely achievable, but I am opting for ball-screw driven system on all axis/at least on some axis.
So What kind of slope would I need to choose, to be able to run all of my axis at about 200mm/s.
Do you think, 5mm of a slope on ACME screws or ball-screws would be enough?
reason for screw-driven axis is that i want to be able to attach some sort of light spindle - like 800Watt Kress Spindle - to do some light milling in Wood, Carbon and Soft Alloy Metals.
I just don`t think, a belt/pulley system would be a good choice for a hybrid machine.
i know, it`ll be a compromise -
for sure, but with th desin I have in mind (no gantry system, but rather a moving Y-table) and the Z- and x-axiis combined, It will be allright and rigidity of the frame will most certainly not be a problem.
it will use either 12 or 16mm supported rails on all axis, so should rund both - smoothly and very stable with minimal play.
I just don`t know which component will limit me the most.
the electronics? How many hertz will the Allow for a signal?
I thought I once read somewhere, that it is the electronics capping the machine`s movement at XXXXXX instructions/pulses a second thus setting a hard limit for linear motion sped.
I want to reach at least 150 or 200mm/s for prints.
For milling such fast speeds would not be required, but for travel moves it would still be a nice bonus.
So which slope would the ball-screws or trapezoidal screws need to have minimum/maximum for the machine to still allow for 200mm/s with 1/128 microstepping
on a RADDS Board?
Don`t worry about the stepper drivers. I may use aftermarket drivers which are rated up to 4A - So I can crank up the power to the motors quite a bit when neccessary.
thanks in advance for any help on this,
as I am kind of lost, which system to use to drive the bed with it`s weight at my wanted speeds.
Alex
I am currently designing my third 3rd 3D printer - after having owned a Powerwas Evo and now printing on a prusa i3 aluminum -
i want both - something bigger and something more rigid.
it is going to be a machine with a frame consisting of Aluminum Extrusion Profiles in either 30x30 or 40x40mm - depended on the size and several calculations and of course motor-decisions - which i plan to
base upon reply to this thread.
Currently my i3 uses m5 - 0.8mm per turn for Z-Axis, and GT2 pulleys with 2 teeth on x and Y-axis.
While th z-axis i sobviously extreeemly slow (I can`t test the real speed, since the m5 threaded rod wasn`t made for linear movement and therefore has a lot of the motor`s torque eaten up by the movement alone and the friction the darn m5 nut is eating up.
With the X and Y-Axis I see them being 20 teeth - 2mms apart - coming out towards 40mm per rotation.
So for 40mm/s the motor would have to have 40rpm and so on.
being 1/16 micro stepping - it requires 3200 Steps per Rotation - ergo 40mm, which equals out to 80 steps per milimeter - which is nice, since it is 1) evenly dividable 2) quite a good resolution while maintaining enough speed.
which the controller should be easily up to.
I have seen videos of people driving their axis with more then 200mm/s
so let us assume, even 5x my speed with same configuration (currently RAMPS 1.4 - Mega 2560) is still doable.
That would be 5x 3200steps per second - coming towards 16000 Pulses per second.
but if I used 1/128 microstepping - which is 8x as much, as I am using now -
i am sure, the RAMPS 1.4 could not hold up.
This would need 128.000 Pulses/s to the motors.
but since I plan on using either ballscrews or trapezoidal leadscrews at about 5mm slope (is that a good value?!) that would come out at even 8 times less movement per full rotation of the stepper motor....
So I would or could easily need the motor do to 1600rpm...
I think I read somewhere the motors hard-limits for nema 17 or nema 23 sized motors is somwhere between 3500-4500rpms - so still room ahead.
but would the controller (RADDS Board) be fast enough to do 1.024.000 pulses/s ?!
I highly doubt it... what is the "hard-limit" here?
100khz? 400khz? Is there such a limit?
How are huge CNC machines moving so fast - are they relying solely on the PC´s processing power - certainly not huh?!
As I am opting for both - an increase in microstepping (at least 1/64 maybe even 1/128 microstepping) for ultrasmooth linear motion - see this link:
[www.dr-henschke.de]
and this Video: [www.youtube.com]
where He tests different stepper drivers and finds out, only the ones with 1764 or 1/128 microstepping are allowing for a really smooth movement of slow moves and that Decay musst be selectable via a trim-poti.
- I am unsure about which speeds I will be able to reach!
I am not sure that with the size of printer i am planning (bed 30x40cm) and it`s inherent need for rigidity and thus weight, nema 17 motors will be enough, I might go for Nema 23, also when doing 1/128 microstepping I am afraid I will not be able to reach higher speeds aany more - even with a RADDS Board and it`s faster processor.
With a GT2 pulley system it would be surely achievable, but I am opting for ball-screw driven system on all axis/at least on some axis.
So What kind of slope would I need to choose, to be able to run all of my axis at about 200mm/s.
Do you think, 5mm of a slope on ACME screws or ball-screws would be enough?
reason for screw-driven axis is that i want to be able to attach some sort of light spindle - like 800Watt Kress Spindle - to do some light milling in Wood, Carbon and Soft Alloy Metals.
I just don`t think, a belt/pulley system would be a good choice for a hybrid machine.
i know, it`ll be a compromise -
for sure, but with th desin I have in mind (no gantry system, but rather a moving Y-table) and the Z- and x-axiis combined, It will be allright and rigidity of the frame will most certainly not be a problem.
it will use either 12 or 16mm supported rails on all axis, so should rund both - smoothly and very stable with minimal play.
I just don`t know which component will limit me the most.
the electronics? How many hertz will the Allow for a signal?
I thought I once read somewhere, that it is the electronics capping the machine`s movement at XXXXXX instructions/pulses a second thus setting a hard limit for linear motion sped.
I want to reach at least 150 or 200mm/s for prints.
For milling such fast speeds would not be required, but for travel moves it would still be a nice bonus.
So which slope would the ball-screws or trapezoidal screws need to have minimum/maximum for the machine to still allow for 200mm/s with 1/128 microstepping
on a RADDS Board?
Don`t worry about the stepper drivers. I may use aftermarket drivers which are rated up to 4A - So I can crank up the power to the motors quite a bit when neccessary.
thanks in advance for any help on this,
as I am kind of lost, which system to use to drive the bed with it`s weight at my wanted speeds.
Alex