[Panovak]

Hi everyone! I'm building a mechmate and thought I'd start a build thread here.
I used i- beams as my rails because they were free! Typically mechmates use c channel. The machine is 6 feet wide and 125" long. Height from top of beams to top of cross members is 8" currentlly.
Next on the list is laying epoxy to flatten the beams in prep for the rails. I'm buying linear rails from automation overstock.
I will be using rack and pinion with servos.
Right now the plan is for acorn controls with dyn4 servos. i need to do more research to figure out gearing and sizing of motors. This is my first go at anything like this so I'm open to any help/ suggestions.
The machine is only for hobby but I still want good performance. It'll mainly be used for wood. But will also do plastics and perhaps some aluminum.

[machinedude]

pretty solid frame to build off of. the I beams will serve you will with big table like you have. if i had the equipment to machine a frame of that size after welding for the linear motion parts i would not think twice about a frame welded out of thick walled tube and i beams like this.

looks good and like a good start. good luck with the build.

[Panovak]

Thanks. I never welded before doing this frame. I rented a welder. Nothing special but this machine will be plenty for what I'll be doing.

[Panovak]

I have a question regarding which motors to run machine.
I just purchased an acorn board. I am now trying to decide between dmm dyn 4 or clearpath servos. Is there a clear difference between the two? I was about to buy the dyn 4 because they were cheaper but they don't include the drive like the clearpath so the difference wasn't as extreme as I thought.
Any help/ suggestions would be great.
Thanks

[machinedude]

DMM is an actual servo system. clear path are more like a closed loop stepper hybrid. if it were me the DMM system would be my choice. the DMM will require the servo motor and a DYN4 drive.

[Panovak]

Ok. Thanks machinedude. I just got a quote from dmm.
3x 750w motors and drives
1x 400w motor and drive
cabling, etc for $2200.

Not gonna lie there's some sticker shock but it seems it'll be worth it.
Thamkst

[machinedude]

clear path have the dive integrated onto the motor so it's all one unit. DMM separates the two components . if you look at the torque speed charts you will notice clear path systems run at a slower RPM rating and the torque will drop quickly. were as a DMM servo will have a good holding torque over a wide range of speed before it begins to drop off at the high end. you can look at the two charts and do a side by side evaluation to see which does better in performance by i think DMM will be a lot better in that department.

[machinedude]

the 750 watt motors are rated for 5000 rpms from dmm clear path is probably nowhere near that fast.

[davida1234]

DMM is an actual servo system. clear path are more like a closed loop stepper hybrid..

That's the first time I hear something like that. Do you have any documentation for that statement?

[machinedude]

That's the first time I hear something like that. Do you have any documentation for that statement?

i have come across a few debates on the topic. this is just my 2 cents on the topic. i have looked at several torque speed charts from clear path and they look more like a torque speed curve charts you would see for a stepper motor chart and this was enough for me. once again this is just my 2 cents.a lot of people like them so they must have some good qualities. i think people like them because of the lack of cables needed. which is nice but if you have problems years down the road are you stuck replacing the whole unit if the drive goes bad or the other way around if the motor would go bad?

the biggest thing is, you have to look at the charts to compare against your needs. and pick the brand that does best for what your building.the 750 watt motors paired with the DYN4 drive running on 240V are hard to beat because the hold the rated holding torque all the way up to around 3500 rpm even after that the decline is a gradual slope in loss.

[Teknic_Servo]

DMM is an actual servo system. clear path are more like a closed loop stepper hybrid. if it were me the DMM system would be my choice. the DMM will require the servo motor and a DYN4 drive.

Hi everyone,

I'm an applications engineer with Teknic and recently came across this discussion. I thought it would be helpful to clarify some misconceptions about ClearPath servo systems.

ClearPath is a fully closed-loop servo system, (not a stepper or a hybrid). To be technically precise (and a bit long-winded), ClearPath is an 8-pole, permanent magnet, three-phase, brushless servo motor with an integrated sine-wave commutated, vector torque-controlled servo drive and high resolution encoder.

ClearPath servos are sometimes mistakenly identified as stepper motors, partly because their torque-speed curves are similar to those of a stepper system (SDSK models in particular), and partly because they take in standard step and direction signals.

ClearPath SDSK models were designed to be drop-in replacements for stepper motors, so their torque-speed curves (high peak torque at lower speeds) are similar to a stepper motor's. This is to help drive stepper-replacement applications (typically lower speed) without requiring additional gearing (especially the ClearPath "S" winding option). That said, ClearPath provides 2-3 times more power when compared to a similarly sized stepper motor.

If you're looking for something more powerful, the ClearPath SDHP ("High Power") models have peak torque available out to much higher speeds. These models were designed to be replacements for other digital servos or stepper motors (where higher machine throughput is important). The SDHP models have 8-15x the power of similarly sized steppers.

If you're curious, here is a link to a video describing the difference between stepper motors and ClearPath servos: https://youtu.be/lt3QSCEgWgs

As machinedude mentioned, your motion component choices truly come down to what you need in terms of machine performance, price, physical space, technical support, availability, etc.

I hope this information was helpful, If anyone has any questions regarding ClearPath servos, please feel free to email [email protected], or give us a call at (585)-784-7454.

- Nick S. Teknic Servo Systems Engineer

[Panovak]

Im looking for help determining what these 4 to 1 belt gears are worth. Any guesses? I cant seem to find anything online like it to compare to. Thanks

[ger21]

Probably only worth something to someone building a Mechmate, then maybe $200-$300?

[TimBerframe]

I know this thread is a couple years old but on the chance you still are around:

Can you show pics of how your linear bearing blocks mount onto the gantry and y car?
How did you mount the rack onto the ibeam?

Your build is almost identical to what I have sketched out for myself

[Robert M]

Probably only worth something to someone building a Mechmate,

.............
Good one Ger....
Robert