Update to M4.1 - Problem with New Arms

Awesome, that’s good to hear. A couple folks reported calibration issues on 0.88 (although it’s working great for me) so it’s good to hear about success :grinning:

Upgrade kit arrived.

2 new arms seem to work fine retract and extend and seem alot smoother.

The other 2 arms will not retract or extend.

Retract returns numbers for all 4 arms, so I assume this means all 4 encorders are working or there would be an error reported.

The 2 arms that dont move return very small numbers.

Have taken these 2 arms apart and the spool and arm moldings seem harder to rotate together than in the other 2 arms.

All the moldings seem to have a few bulges on the mating surfaces at the screw hole and rib positions, not sure what else could be causing the issue.

I have upped the retract current to 2000, still not budging.

Will move at 2400. But not exactly the low friction low current outcome described above.

Any ideas before full assembly and calibration would be appreciated.

Hmm that’s concerning, how much harder are we talking? Any chance you could get a video?

They will turn but it is a noticeable difference turning by hand.
They first 2 are very easy and smooth to turn by hand and function nicely at 1300 retraction current.

The second 2 are slightly stiffer but stick and release at times and a significantly higher retraction current of 2400 is needed to get them moving smoothly.

Will try to get some photos and possibly a video tomorrow. Getting dark here,and the shed lighting is not so good.

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Both of those numbers seem really high to me like there is something going on. With the upgrade I was able to drop my retraction force all the way down to 900, and I bet I could go lower

The first 2 may well work at lower current.
1300 was, from memory, what the firmwware was set to out out of the box.

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Here is 3D printable version of the shim, it’s 3mm thick and appears to leave enough room that friction between the arms is not an issue.

Maslow4.1_Shim_Ring.stl (36.0 KB)

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I wonder if maybe the belt guard is catching on the spool gear?

To me this sounds like something is jamming the normal motion

Suggest pinning your video bar at the top of the forum or including it in the front page instructions. I was this a couple days ago and it took me an hour to find it again.

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Assembling the upgrade kit arms now. I’ve found with a T10 full sized screw driver I can just push the bolts in place.

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It’s at the top of this page: 4.1 Upgrade Instructions — Maslow

But maybe that page is too hard to find?

Suggest you add a link in the “About Maslow” page referencing the 4.1 Upgrade Instructions.

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Maybe. I’m also building from scratch using the original kit and the upgrade kit instead of actually performing an upgrade so I might not have been searching for the right thing.

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I had a similar experience.
Two of the arms rotated freely, while the other two were stiffer. I applied a bit of PTFE + silicone grease to all four arms (though it didn’t help much, as the stiff arms were still hard to rotate by hand). However, after reassembly, everything worked perfectly.

On version 4.0, my device struggled to retract the belts with the force set to 1400. I had to click “retract” multiple times, with each attempt only pulling the belts back by a couple of centimeters. Eventually, I increased the force to 1600. The fitness score was 1.15029 (using v0.87).

After upgrading to 4.1, despite the stiff arms mentioned earlier, I ran the v0.87 calibration with the force set to 1400, and the fitness score improved even further. Finally, I upgraded to v0.88, lowered the force to just 900, and achieved a similar fitness score - 1.17671.

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I think the binding which occurred when the gears were too close together had more effect (due to mechanical advantage) than any stiffness between the plastics. I also initially had difficulty turning the spooled belt by hand, but it did not affect the way it worked after assembly. The binding between the gears is a lot freer then the original.

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Yeah, I think that this is a factor also.

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Have totally dismantled and reassembled. Could not find any issues, but made sure to pull the motors tight towards the end of the arm when remounting them.

Now all arms retract with 900 in the settings. So that fixes that issue.

Now it fails calibration every time.

Also I seem to have to wait half hour with the power off or it won’t connect to the wifi. if power cycled with a normal 10 -30 sec pause it cannot be connected to.

Makes trouble shooting a real drawn out process.

running .88 firmmware on a 4.1 upgrade.

Calibration just says fitness failed and goes in to a loop of recalculation, until powered off.

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Seriously, that is super annoying. I have no idea what is going on there. Is it the same in access point mode and when connected to your home WiFi network?

Does it do this every time?

I thought if it couldnt find my wifi then i would then default to its own, but that does not seem to happen. I does not appear on my wifi and Maslow wifi is not available, but leave it off for half hour or so and it will connect to my wifi straight away.

I had it once move through all 30+ moves then say failed and start recalculating, most time fails after the first set of moves, then start recalculating.

Flex values at the start vary from 2.** - 7.** but are never the same or close to previouus calibrationn runs. I had calibration issues to begin with when 4.0 was built originally but that fixed and calibrated with a firmware update so I beleive the frame is fine.

To me this sounds like it’s connecting to your wifi, but then maybe something funky is happening between the machine and your wifi router which is preventing it from showing up on the network. You are 100% correct that if it can’t connect to your wifi it will create it’s own network.

Could the issue be magnet slip?

If you do Retract All → Extend All → Retract All it should print out some numbers which should be very close to 0. Is that what you are seeing?