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Upgrading XY motors to double bearings and all metal gears

Thinking of upgrading the XY motors in the kit.
These new motors have all metal gears and double ball bearings. they are about the same speed. I’m going to see if Aslong can put on a new connector to match the exsisting cables. if not I can get adapter cable made I guess.

This is the motor currently used:
http://www.etonm.com/products_detail/productId=89.html
It just has bare metal shaft, no bearings on either side and one plastic gear.
I need to test them out and see how long they last.
any suggestions for good testing methods?
I would imaging cuting at the top middle would be the most stressful test and best way to quickly see if any issues come out?

any motor experts out there let me know what you think please.

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Just my 2 Fils, the RPM is just a fraction smaller then the [current](https://github.com/MaslowCNC/Electronics/blob/master/Documentation/Data%20Sheets/ET-WGM58AE-1220.6(20171108003-H16035)%20Model%20(1).pdf) motor. Thinking that we soon will have acceleration and deceleration planing, would it make scene to look for new motors that can provide more speed?

Edit: Do you have a data-sheet with the ‘on load torque’?

I’ll ask them what they can do, might make sense to have a higher voltage.

That would mean new power supply and perhaps new motor shield. Can’t find a data for the TLE5201, but the 9201 seems to handle 28V, can’t tell about the other components on the board. Changing from 12V to 24 should speed them up I guess. :slight_smile:

Not a motor expert, but I’m curious to see how much weight I could get one to lift before stalling while measuring current. It might make sense to hook it up to a bike power meter and measure the wattage output or connect one to a larger sprocket and measure torque the old fashioned way. Could be interesting.

Current x/y motors are rated at 30kg (~66.1387 lbs) ‘on load torque’. A had a spring scale attached to the chain while trying to figure out how much the 'Pull Tight" for measuring the motor distance actually pulled. It was in this test that 2.5mm thickness u-steel twisted and a chain went flying in the workshop. It went beyond the 30kg for sure but was to fast to see how much this beasts are actually pulling.
So happy that this way of roughly estimating the motor distance will be history soon.

Edit: Stall in the data-sheet is only mentioned in current. 14.8A max. The reason why i fried 3 original motor-shieds and 1 original power supply during testing i early days, so disclaimer:

Do not try this at home and surly not with the original shield and power supply. Permanent damage my appear and your supplier can not be held accountable for the misuse of the equipment.

Is a good sales argument, however it is not the plastic one that is failing in the original motors. It’s a metal one. Wondering if a more ‘balanced’ gear ratio would spread out the forces? No idea, just got hooked up on the topic of new motors.

For reference, the original motor was ET-WGM58AE-1220.6 (20171108003-H16035).
etonm is listing a ET-WGM58A-1220.6 with (E missing) with higher specs (no-load and on-load) than in the data sheet we have and a ET-WGM58A-1227.6 with specs almost matching the current motors more.

Edit: The gear ration was wrong to begin with Whats inside the gearbox/motor? , so every other numbers that are provided from china (including those that made 2020 a year in history for human kind) should be questioned at start before making bulk orders or decisions. Test the RPM (no-load and on-load {average Maslow weight?}), test the stall current by blocking them, see what gear brakes, or just send me 2 and I will try my best to kill them :grin: Disclaimer: Yes I got to hooked up to the topic and went to far. Yes, I did have toxic liquids. I kindly ask for apology and know that I should stop now and will. Sorry.

Kind regards, Gero

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http://www.bringsmart.com/pd.jsp?id=29#pp=0_394-1%7E-1%7E0%7E2


5A, runs a bit faster at 23rpm double the torque, but 5a would only work on the newer TLE boards. and you would need a new power supply. I wonder what the normal amp draw is ?

lower power

The torque is not what i’m concered about, i was running the 2nd heaviest sled for a while, till i moved to light weight. I think we could keep the torque or even sacrifice a bit for more speed.

how much speed 35 rpm? 24 or 23rpm are all stock choices above. I think 35rpm is really pushing your luck. 24 or 23 would be safer bets.

How much RPM are we currently getting? Will check that at the workshop tomorrow and provide the answer. From what I remember is that we are limited hard-coded by the firmware to F1000 and default in GC is F800. Wow that relates to RPM and how fast we could actually go is from my perspective somethig that people like (alphabetically) @bar @blurfl @dlang @MeticulousMaynard @Orob @zaneclaes and sorry for those i missed would be able to answer. The true ratio, the true Amps is something to be checked and tested thoroughly before designing a new shield (if that is even necessary).

Edit: @krkeegan is one of my misses, i apologize. Please feel free to add the others i missed.

Sorry to come uninvited. I value your opinion a lot and there is something on what i would like your opinion about (if you don’t mind).
Acceleration planning seems to be trending now, but do you think it’s necessary?

I know it is a must on heavy commercial cnc machines operating at high speeds, if not decelerated/acceleratd before its intended stop/start (or when reaching a curve) the inertia of the gantry alone (usually very heavy) will force the motors to keep turning pushing them out of its intended path and missing steps.

GRBL comes to the rescue for smaller Y/X hobbyist machines, although they usually don’t have heavy gantries, they still move fast enough to be affected by inertia due to being driven by belts and weak steppers.
But Maslow moves at a very slow pace to have any considerable inertia, it does not have harmonics resonance problems like all metal cnc machines, and most important it uses WORM geared motors which will make next to impossible for the sled to pull the motors out of position. What i’m I missing?

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I would not use nor would I recommend using any Maslow hardware (other than maybe a motor mount bracket) to test the motors to their rating… Direct DC with a potentiastat to control current and a couple motors would probably be required to do it. Remove everything unneeded. No Darwin award considerations.

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With a router on chains, on a frame angled at vertically ~15° with gravity as one of the aspects for accuracy, the ‘overshoot’ by speed is what i would consider.

I thought it was the instant start/stop speed expectation that has caused the “sled not keeping up error” that acceleration planning is expected to remedy.

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A TLE5206 and a 12V 10A power supply does give you some chance to test, but also the chance to ruin your setup. Agreed, do only at own risk and if you are willing to buy replacement parts.

20rpm, but it is throttled back about 20% by the firmware settings which I think are set to 800mm/min
23rpm would increase it 15% or 35% faster than stock if the firmware is pushed to the max.

The holding torque on the motors would make impossible for the sled to go beyond its intended stop, and with a sled that’s in constant friction with the board moving a max 30in/minute i can’t imagine it overshooting.

I believe it’s more of a weak shield problem, you can also have acceleration control via G-code