# Update to M4.1 - Problem with New Arms **URL:** \ **Category:** Technical Details\ **Created:** [January 25, 2025, 5:48am UTC](https://forums.maslowcnc.com/t/update-to-m4-1-problem-with-new-arms/23241 "2025-01-25T05:48:25Z")\ **Posts on this page:** 20\ **Page:** 2
**Author:** ![bar](https://yyz1.discourse-cdn.com/flex031/user_avatar/forums.maslowcnc.com/bar/32/10_2.png) [@bar](https://forums.maslowcnc.com/u/bar)\ **Post date:** [January 29, 2025, 12:15am UTC](https://forums.maslowcnc.com/t/update-to-m4-1-problem-with-new-arms/23241/21 "2025-01-29T00:15:21Z")
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 😀 ---
**Author:** ![stuart\_powles](https://yyz1.discourse-cdn.com/flex031/user_avatar/forums.maslowcnc.com/stuart_powles/32/22891_2.png) [@stuart\_powles](https://forums.maslowcnc.com/u/stuart_powles)\ **Post date:** [January 29, 2025, 2:28pm UTC](https://forums.maslowcnc.com/t/update-to-m4-1-problem-with-new-arms/23241/22 "2025-01-29T14:28:23Z")
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. ---
**Author:** ![bar](https://yyz1.discourse-cdn.com/flex031/user_avatar/forums.maslowcnc.com/bar/32/10_2.png) [@bar](https://forums.maslowcnc.com/u/bar)\ **Post date:** [January 29, 2025, 3:47pm UTC](https://forums.maslowcnc.com/t/update-to-m4-1-problem-with-new-arms/23241/23 "2025-01-29T15:47:35Z")
> [@stuart\_powles](#): > > Have taken these 2 arms apart and the spool and arm moldings seem harder to rotate together than in the other 2 arms. Hmm that’s concerning, how much harder are we talking? Any chance you could get a video? ---
**Author:** ![stuart\_powles](https://yyz1.discourse-cdn.com/flex031/user_avatar/forums.maslowcnc.com/stuart_powles/32/22891_2.png) [@stuart\_powles](https://forums.maslowcnc.com/u/stuart_powles)\ **Post date:** [January 29, 2025, 4:24pm UTC](https://forums.maslowcnc.com/t/update-to-m4-1-problem-with-new-arms/23241/24 "2025-01-29T16:24:14Z")
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. ---
**Author:** ![bar](https://yyz1.discourse-cdn.com/flex031/user_avatar/forums.maslowcnc.com/bar/32/10_2.png) [@bar](https://forums.maslowcnc.com/u/bar)\ **Post date:** [January 29, 2025, 5:37pm UTC](https://forums.maslowcnc.com/t/update-to-m4-1-problem-with-new-arms/23241/25 "2025-01-29T17:37:14Z")
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 ---
**Author:** ![stuart\_powles](https://yyz1.discourse-cdn.com/flex031/user_avatar/forums.maslowcnc.com/stuart_powles/32/22891_2.png) [@stuart\_powles](https://forums.maslowcnc.com/u/stuart_powles)\ **Post date:** [January 29, 2025, 5:42pm UTC](https://forums.maslowcnc.com/t/update-to-m4-1-problem-with-new-arms/23241/26 "2025-01-29T17:42:08Z")
The first 2 may well work at lower current. 1300 was, from memory, what the firmwware was set to out out of the box. ---
**Author:** ![David\_Procter](https://yyz1.discourse-cdn.com/flex031/user_avatar/forums.maslowcnc.com/david_procter/32/23121_2.png) [@David\_Procter](https://forums.maslowcnc.com/u/David_Procter)\ **Post date:** [January 29, 2025, 7:47pm UTC](https://forums.maslowcnc.com/t/update-to-m4-1-problem-with-new-arms/23241/27 "2025-01-29T19:47:41Z")
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](https://forums.maslowcnc.com/uploads/short-url/wkVhTErsbJpsVXMQlyoVKjX0Z9f.stl) (36.0 KB) ![IMG_7207](https://canada1.discourse-cdn.com/flex031/uploads/maslowcnc/original/3X/6/9/692daf324560a1da23eec77d391c45821dbd832c.jpeg) ![IMG_7208](https://canada1.discourse-cdn.com/flex031/uploads/maslowcnc/original/3X/a/0/a036befd92ab070e98d8c90ca7d56f02b76fad59.jpeg) ![image](https://canada1.discourse-cdn.com/flex031/uploads/maslowcnc/original/3X/0/f/0f998367bd7094ac6aa93aabfb93db303130b65d.jpeg) ---
**Author:** ![bar](https://yyz1.discourse-cdn.com/flex031/user_avatar/forums.maslowcnc.com/bar/32/10_2.png) [@bar](https://forums.maslowcnc.com/u/bar)\ **Post date:** [January 29, 2025, 8:08pm UTC](https://forums.maslowcnc.com/t/update-to-m4-1-problem-with-new-arms/23241/28 "2025-01-29T20:08:57Z")
> [@stuart\_powles](#): > > The 2 arms that dont move return very small numbers. I wonder if maybe the belt guard is catching on the spool gear? To me this sounds like something is jamming the normal motion ---
**Author:** ![Melvin](https://avatars.discourse-cdn.com/v4/letter/m/77aa72/32.png) [@Melvin](https://forums.maslowcnc.com/u/Melvin)\ **Post date:** [February 6, 2025, 7:53pm UTC](https://forums.maslowcnc.com/t/update-to-m4-1-problem-with-new-arms/23241/29 "2025-02-06T19:53:37Z")
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. ---
**Author:** ![Melvin](https://avatars.discourse-cdn.com/v4/letter/m/77aa72/32.png) [@Melvin](https://forums.maslowcnc.com/u/Melvin)\ **Post date:** [February 6, 2025, 8:27pm UTC](https://forums.maslowcnc.com/t/update-to-m4-1-problem-with-new-arms/23241/30 "2025-02-06T20:27:57Z")
Assembling the upgrade kit arms now. I’ve found with a T10 full sized screw driver I can just push the bolts in place. ---
**Author:** ![bar](https://yyz1.discourse-cdn.com/flex031/user_avatar/forums.maslowcnc.com/bar/32/10_2.png) [@bar](https://forums.maslowcnc.com/u/bar)\ **Post date:** [February 6, 2025, 8:36pm UTC](https://forums.maslowcnc.com/t/update-to-m4-1-problem-with-new-arms/23241/31 "2025-02-06T20:36:00Z")
It’s at the top of this page: [4.1 Upgrade Instructions — Maslow](https://www.maslowcnc.com/41-upgrade-instructions) But maybe that page is too hard to find? ---
**Author:** ![ian\_ab](https://avatars.discourse-cdn.com/v4/letter/i/a587f6/32.png) [@ian\_ab](https://forums.maslowcnc.com/u/ian_ab)\ **Post date:** [February 6, 2025, 8:39pm UTC](https://forums.maslowcnc.com/t/update-to-m4-1-problem-with-new-arms/23241/32 "2025-02-06T20:39:16Z")
Suggest you add a link in the “About Maslow” page referencing the 4.1 Upgrade Instructions. ---
**Author:** ![Melvin](https://avatars.discourse-cdn.com/v4/letter/m/77aa72/32.png) [@Melvin](https://forums.maslowcnc.com/u/Melvin)\ **Post date:** [February 6, 2025, 11:34pm UTC](https://forums.maslowcnc.com/t/update-to-m4-1-problem-with-new-arms/23241/33 "2025-02-06T23:34:42Z")
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. ---
**Author:** ![wlkmnn](https://yyz1.discourse-cdn.com/flex031/user_avatar/forums.maslowcnc.com/wlkmnn/32/26285_2.png) [@wlkmnn](https://forums.maslowcnc.com/u/wlkmnn)\ **Post date:** [February 16, 2025, 7:15pm UTC](https://forums.maslowcnc.com/t/update-to-m4-1-problem-with-new-arms/23241/34 "2025-02-16T19:15:52Z")
> [@stuart\_powles](#): > > Have taken these 2 arms apart and the spool and arm moldings seem harder to rotate together than in the other 2 arms. 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. ---
**Author:** ![ian\_ab](https://avatars.discourse-cdn.com/v4/letter/i/a587f6/32.png) [@ian\_ab](https://forums.maslowcnc.com/u/ian_ab)\ **Post date:** [February 16, 2025, 7:36pm UTC](https://forums.maslowcnc.com/t/update-to-m4-1-problem-with-new-arms/23241/35 "2025-02-16T19:36:15Z")
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. ---
**Author:** ![md8n](https://yyz1.discourse-cdn.com/flex031/user_avatar/forums.maslowcnc.com/md8n/32/28197_2.png) [@md8n](https://forums.maslowcnc.com/u/md8n)\ **Post date:** [February 16, 2025, 10:14pm UTC](https://forums.maslowcnc.com/t/update-to-m4-1-problem-with-new-arms/23241/36 "2025-02-16T22:14:09Z")
> [@ian\_ab](#): > > The binding between the gears is a lot freer then the original. Yeah, I think that this is a factor also. ---
**Author:** ![stuart\_powles](https://yyz1.discourse-cdn.com/flex031/user_avatar/forums.maslowcnc.com/stuart_powles/32/22891_2.png) [@stuart\_powles](https://forums.maslowcnc.com/u/stuart_powles)\ **Post date:** [February 25, 2025, 1:17pm UTC](https://forums.maslowcnc.com/t/update-to-m4-1-problem-with-new-arms/23241/37 "2025-02-25T13:17:01Z")
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. ---
**Author:** ![bar](https://yyz1.discourse-cdn.com/flex031/user_avatar/forums.maslowcnc.com/bar/32/10_2.png) [@bar](https://forums.maslowcnc.com/u/bar)\ **Post date:** [February 25, 2025, 5:18pm UTC](https://forums.maslowcnc.com/t/update-to-m4-1-problem-with-new-arms/23241/38 "2025-02-25T17:18:04Z")
> [@stuart\_powles](#): > > 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. 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? > [@stuart\_powles](#): > > Calibration just says fitness failed and goes in to a loop of recalculation, until powered off. Does it do this every time? ---
**Author:** ![stuart\_powles](https://yyz1.discourse-cdn.com/flex031/user_avatar/forums.maslowcnc.com/stuart_powles/32/22891_2.png) [@stuart\_powles](https://forums.maslowcnc.com/u/stuart_powles)\ **Post date:** [February 25, 2025, 6:30pm UTC](https://forums.maslowcnc.com/t/update-to-m4-1-problem-with-new-arms/23241/39 "2025-02-25T18:30:32Z")
> [@bar](#): > > 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? 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. > [@stuart\_powles](#): > > Does it do this every time? 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. ---
**Author:** ![bar](https://yyz1.discourse-cdn.com/flex031/user_avatar/forums.maslowcnc.com/bar/32/10_2.png) [@bar](https://forums.maslowcnc.com/u/bar)\ **Post date:** [February 26, 2025, 10:29pm UTC](https://forums.maslowcnc.com/t/update-to-m4-1-problem-with-new-arms/23241/40 "2025-02-26T22:29:04Z")
> [@stuart\_powles](#): > > 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. 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? [Previous page](https://forums.maslowcnc.com/t/update-to-m4-1-problem-with-new-arms/23241.md?page=1) [Next page](https://forums.maslowcnc.com/t/update-to-m4-1-problem-with-new-arms/23241.md?page=3)