For those that were not part of the Kickstarter: Where to obtain the main motor/worm gear/encoder

Hardware
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It seems like many people (myself included) are very excited to participate in this community, but are pretty sidelined given the inherent scarcity of the motors used. The rest of the parts are fairly easy to come by it seems. I understand there are more kits and motors on the way, but I’m concerned that this will be an ongoing problem with a single motor supplier and a relatively uncommon set of specs.

Is there an opportunity to make the motors more accessible? It would be so cool if the motors used were widely available and not limited to only a single manufacturer.

Is anyone in the community skilled enough to create a firmware branch that supportes super common NEMA 17 or NEMA 23 stepper motors + a worm driven gear box? I know someone already did it, but I’m unclear on the results. Seems like there might be an opportunity to improve upon the max feed rate while simultaneously providing a more accessible solution for everyone that is waitlisted. No doubt it would be more expensive, but at least there’d be a feasible path to building a Maslow without the kit. I am not a strong programmer, but maybe it’s time to start learning?

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There is a fork that supports stepper motors, but you still need a worm gear set
for them (there was a thread on the old forum for this). It was significantly
more expensive to go the stepper route.

We are expecting that around the end of this month, new kits will become
available. They have ordered the parts, but they haven’t all arrived yet.

David Lang

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Plus this is an open source project, fork and modify it to meet your needs while making sure to keep the proper attributions.

Learning new skills is rarely a waste, although so of us trying to learn fusion360 might feel differently

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Thanks for the input @mooselake. I’m new to open source projects and pretty inexperienced with programming (basic matlab and c), but I agree. Given the nature of this project and the outstanding community, only excuses stand in my way.

Hope you’re right about the kits @dlang and that there are plenty of them to go around.

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Just a thought; For those seeking replacements to the “official” parts, have you considered sourcing motors and gearboxes separately?

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I started looking into sourcing the motors, gear boxes, and encoders sepatately, but probably not enough. I’ll continue the search. Thanks for the suggestion.

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Having given some thought to comments from @TheRiflesSpiral what do you guys think about this motor:

Doesn’t quite match the torque of the current 20 rpm motors since they rotate a bit faster, but it’s the best match I could find. Also quite a bit more expensive for a motor without an integrated encoder. Might not be worth it if bar is really going to have motors/kits available soon, but thought I’d share anyway.

I’d still need to find an encoder to go with it. If anyone has a source for those, please share.

On slightly different topic, has anyone considered using a more capable 24v motor such as this?

It would be so nice to have feed rates in the 100 ipm range, although I’m not sure how the whole system would feel with those increased speeds.

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those look like the right ballpark at least. The first is a little lighter, but
should ork, the second is both more powerful and faster.

the 24v motor would need a different power supply and motor controller board,
but would be both faster and more powerful

those really do look like the right gearboxes.

now you just need to add an encoder. If you put it on the output shaft, a 1000
pulse/rev encoder like this (4000 pos/rev)


or this 2000 pulse/rev one

should do nicely.

David Lang

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@JaceD Let’s do this. That motor could use upgrade anyway. Plus I think a lot of people would appreciate to have another option of motor so they do not have to wait each time the motors run out of inventory. I have build my own design 2’x3’ CNC machine with Nema 23 motors and TinyG controller. I have no experience with worm gears or encoders though. @dlang could you please shed some light at what is involved in adding an encoder to that first motor? When we are done with that first weaker but faster first motor we could try 24 volt version with adequate motor controller.

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@cncx my current plan is to build out a stock Maslow kit and get to know it’s ins-and-outs, then upgrade the motors to a 24V variant with appropriate driver. I think that will end up being a quicker path to the same result with less effort for me personally given the latest Wednesday update regarding upcoming kit availability. I’ll report back on progress. Let me know if you decide to try either of these motors out!
Is the machine you built a hanging plotter style machine similar to Maslow, or a more traditional gantry style machine?

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I was wondering if anyone has suggested the worm gear combination that is used in BMW style window regulators? I know they are 12 volt and I have been looking at pictures of them, they seem to have four wires, and they should be pretty darn cheap if you go to a pick and pull junkyard to source them.

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To all that have been following and coming up with suggestions for those of us not in on the kit buy but wanted to build the Maslow. As I stated quite awhile ago, I broke down and purchased some motors that were actually very funny on arrival. These things (which I will link) showed up via epacket in like 9 total days, but on opening I started laughing because I knew they were going to be small but these were tiny. Oh well, my idea was to build the machine with the changes I had in mind and "what the hell, try the motors) until I could source others or all together put together different driver / motor solution. So, much time has gone by and I admit with having to build in between life events with only 30 mins a pop available, many unplanned design choices taken. Some times things just work out. Yesterday I was able to make some first cuts and sans a better calibration, it works!

The motors are tiny but cheap 12v 324:1 19rpm 11 ppr, torque is 16 kg/cm …so they have decent torque (not the 30 required by project) but I planned on a few changes, most important was my sled weight. I had to use my Triton router-2.25 hp and not small. Figured it would be too heavy but no, works great and will be using an extra of the same motor I have due to one had broken encoder…got new hall sensor and running fine. It will fit right on the included router lift designed into the Triton. I will publish pics of all this including the z axis as soon as i hook up z axis.

https://m.ebay.com/itm/Hightorque-Turbo-worm-Geared-motor-GW370-DC12V-19RPM-motor-with-encoder-/142034134122?txnId=1434973548004

I also made the machine smaller to aim for bit over 4x4, due to space and desire to just build already. The main positive to my frame (this was " plan while build " so looks ugly) is that knowing that top bar is the most important to accuracy (frame wise) I used a steel bed frame half and attached wood. Then used very strong Baltic Birtch ply. Got very lucky on positioning and current frame can have me hang off the end and jump up and down with barely any flex whatso every. It is super ridgid.

Sorry no pics yet, but I promise I will post them as soon as I set it back up…it is modular so it can be moved into back room.

Anyway, just wanted you all to know that this little, cheap motor worked to make a workable (take with grain of salt…super slow, plus size of sled smaller than most I think…but not by much as router alone is 5kg. Hope my link worked.

Have not had time to even keep up until this week so excited to see the user base growing!

T

P.S. obviously this motor choice will limit the functionality of the machine, but my main goal was to build a working version that may be smaller but still usable and representative of full size, allowing me to try different ideas along with the community as well as have a work space of at least 4x4.

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Pics would be great. Video would be nice to see too. Thanks for this discovery!

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I have a setup with the 1000P/R on the back output shaft and it has been nothing but nightmares. Getting the encoder to stay put took a few revisions and the Arduino seems to not be reliable in reading (or the encoder quality) that high of a PPR.

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The stock setup is 8k P/R, so you should not be having problems with the arduino
reading it fast enough, unless you are spinning a lot faster than the stock
machine.

David Lang

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I agree as I have 1:324 x 11 x 4=14,256 ppr…now I only have the x and y running(z going on today and using same motor so crossing fingers on supporting 3 running that fast.)

The quality of the pulse could get in the way I would think though.(your encoder…if you were having so many issues)

I was really concerned with too high a number of pulses, but so far so good. Plus, when trying to source the closest (for compatibility) motor, you realize that a direct or close replacement is very hard to nail down. I would have just build beefier but wanted to stick to the default as best possible for participating in the forums.

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I am going to pick up two of these: 24V 1:280 22RPM 70kgcm, 11PPR

More than strong enough and my arduino shield is a re-purposed 70V/30A driver so the extra power is easy.

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those look very close to the stock maslow motors, the 280:1 12v version looks almost exactly like the stock motor specs

If I were getting them, I would look really hard at the 1008:1 24v version

just a little weaker, a little lower encoder count, but the pulses/rev we have no are far higher than we need.

108:1 is 4752 pulses/rev, and with an 11 tooth gear (1.65 in per rev) = a pulse every 0.000347 in, far more precision than we need (especially with the recent improvements)

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This is why I tried a 1000PPR encoder directly on the output shaft giving 0.00165in/pulse which is still plenty. Unfortunatly making a quality 1000+ PPR encoder is WAY more difficult than a 11PPR that’s spinning faster.

The 108:1 motors have a way higher RPM on the output, If you run them at a lower RPM you will sacrifice torque, I figure its better to get something that will run at %80+ and then try 12 or 15 tooth gears for speed increases.

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it doesn’t matter if you go with larger sprockets or lower gear ratios, the
effecton force is the same.

But if you look at the 24v 108:1 motor, it’s rated at 25Kg-cm while the stock
maslow motors are 30Kg-cm, so you are very close in terms of force on the chain.
you can then put larger sprockets on to increase speed more (at the cost of
force)

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