# Z20 axis Issues **URL:** \ **Category:** Original/PRO Series (Buildbotics) (Gen 1)\ **Created:** [July 28, 2023, 4:40pm UTC](https://forum.onefinitycnc.com/t/z20-axis-issues/21642 "2023-07-28T16:40:10Z")\ **Posts on this page:** 1\ **Showing post:** 5
**Author:** ![349iq2345](https://avatars.discourse-cdn.com/v4/letter/3/bb73d2/32.png) [@349iq2345](https://forum.onefinitycnc.com/u/349iq2345)\ **Post date:** [July 30, 2023, 1:30am UTC](https://forum.onefinitycnc.com/t/z20-axis-issues/21642/5 "2023-07-30T01:30:20Z")
Hey Robert, did you try that: > [@Z-20 (Heavy Duty Z-Slider)](https://forum.onefinitycnc.com/t/z-20-heavy-duty-z-slider/20499/2): > > Additionally when using a heavier milling motor, you can adjust (increase) the ‘ **drive-current** ’ and ‘ **idle-current** ’ settings the “[Motor → Power](https://buildbotics.com/manual-v1-0/#power)" section of motor 3 on the [MOTORs page](https://buildbotics.com/manual-v1-0/#motorstab). > [@349iq2345](#): > > Also the Z stepper wire can fail due to invisible cable break as it lacks strain relief. > > I would check all the points in the help document “[Troubleshooting: Rail is getting hung, stuck, or out of alignment](https://forum.onefinitycnc.com/t/troubleshooting-rail-is-getting-hung-stuck-or-out-of-alignment/10826)” one by one. > > Also note that cables not only fail on their connectors. A multimeter can help. Also be aware that neither Onefinity cable is made for permanent motion in a CNC. Sometimes [replacing the curly Z cable](https://www.onefinitycnc.com/product-page/z-axis-curly-cable-for-all-sized-machines), that can break internally, or [retrofitting strain relief](https://forum.onefinitycnc.com/t/strain-relief-for-x-gantry-molex-connectors/11461) on the machine can help (or better retrofitting a drag chain system that runs cables specifically made for permanent motion). > [@1F Journeyman losing it's x-axis](https://forum.onefinitycnc.com/t/1f-journeyman-losing-its-x-axis/20094/4): > > To check the cable, I would unplug it on the controller side and on the other end and check all four wires one by one for conductivity between both ends, by using a multimeter set to resistance (ohms). But it could be that you measure that everything is okay because the fault my appear only in certain moments, in certain positions of the cable, when you move it, etc. Usually it’s the motion on a cable that is not made for permanent motion that can make problems after a while, mostly where the individual wire is crimped into the contact, or between the contacts which unfortunately are only tin-plated which means movement and/or corrosion can wear the plating leaving the bare copper open to air which is even more prone to corrosion. In this case, a little amount of [KONTAKT 60](http://www.kontaktchemie.com/KOC/KOCproductdetailV2.csp?product=KONTAKT%2060) and then [KONTAKT 61](http://www.kontaktchemie.com/KOC/KOCproductdetailV2.csp?product=KONTAKT%2061) can help. You need to load the correct configuration: - [Installing the Z-20 Heavy Duty Z Slider (configuring the software)](https://forum.onefinitycnc.com/t/installing-the-z-20-heavy-duty-z-slider-configuring-the-software/18666). This applies to firmware [1.2.1](https://github.com/OneFinityCNC/onefinity-firmware/releases/tag/v.1.2.1) and later. > [@Installing the Z-20 Heavy Duty Z Slider (configuring the software) (BB Controllers)](https://forum.onefinitycnc.com/t/installing-the-z-20-heavy-duty-z-slider-configuring-the-software-bb-controllers/18666/1): > > ![55](https://us1.discourse-cdn.com/flex022/uploads/onefinitycnc/original/3X/0/7/074d4ce6b8a0dc77828017e14dcd2e1c93b8b47b.jpeg) Should you be on firmware [1.0.9](https://github.com/OneFinityCNC/onefinity-firmware/releases/tag/v1.0.9) or earlier, after installing [Z-20 assembly](https://www.onefinitycnc.com/product-page/z-20-heavy-duty-z-slider), you need to set these values of **Motor 3** on its MOTOR page **manually** instead: - “ **travel-per-rev** ” to “ **10** ” - “ **min-soft-limit** ” to “ **-160** ”, and - “ **max-velocity** ” to “ **7** ” This is what the “Pick your Z Slider Type” choice sets (as shown in the image) above when choosing “Z-20 Heavy Duty”. The Z-20 assembly **will** work correctly if you set it manually this way. The standard configurations apply to the weight of the Makita Router. --- _[View the full topic](https://forum.onefinitycnc.com/t/z20-axis-issues/21642)._