Offboard controller on LR V4

LowRider CNC Your Builds
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I am currently starting my LR V4 build (all parts printed, all component purchased). I modified my previous V3 quite a bit, to suit my personal requirements and preferences. One of the mods I did was to place my control screen for the SKR Pro offboard. I had built a case around my CNC setup, to reduce noise and dust, and wanted to be able to control the machine from outside the case (I only use my PC to send and initiate my jobs as comms are too laggy/unreliable).
I ran the cable for my BTT TFT35 from the onboard SKR Pro, through a drag chain and then outside the box. This setup works great.
I am contemplating taking this one step further, and taking the controller offboard and outside of my case, running all of my motor/switch wires through the drag chain. This will have the advantage of eliminating issues due to vibration and dust. Plus, I am intending on using my SKR Pro for the initial build, as I have everything set up to use it already, but I have also purchased a Jackpot board, which I want to try in the near future. Having the controller offboard would make this change a lot easier.
Does anyone see any issues in what I am proposing to do?

Slightly seperately, It would have been useful to be able to work out all of the dimensions for the LR4 based on the footprint of my LR3, i.e. have the rails mounted in the same place (my rails are mounted on Uni-Strut to enable Doug Joseph’s hidden belt mod). I don’t know if the rails are going to be in the same place until I build it, as I am basing everything on cutting area.

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So I had my skr and screen both separate from the LR3. Same idea just ran wires through a drag chain to my stationary control spot. It works fine but I noticed some endstops were intermittent. As for running a program I had no issues.

With that said, you’ll use less wires keeping the control board close to the machine and just have the screen separate, which is what I am planning with my lr4 as I will be staying with my skr. Less cables, the housing for the skr board is minimal and fits nicely on the rails.

Personally, if I thought about it sooner, I would of kept the control board with the LR3 and just had the tft35 stationary. It just makes more sense for my use case since once the skr is setup, you shouldn’t have to touch it, while the screen you do

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I found that when I increased the length of the wiring from the endstops to the controller (beyond a single extension cable) that the well known SKR endstop issue appeared (required adding resistors or removing LEDs). Prior to that I had no issues. So changing the impedance of the circuit by lengthening the wires seems to have some effect on this issue.

Also having connections in a moving cable bundle can cause intermittent failures of both the motors and endstops. Soldering, or folding the connectors before taping them will mitigate this.

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