One of two of my sides on the Z axis does not move up when I’m milling.
But when I control it through the LCD screen manually they both move up evenly.
What is the problem? Is it sometime I’m doing wrong inside fusion 360?
I don’t have an immediate answer, but more information would be helpful.
- This is a LowerRider correct?
- Is this a new build that has never worked, or is this a new problem on a machine that was working fine?
- What control board are you using?
- How is your control board wired (serial or dual endstop)?
- A picture of your control board and its wiring would be helpful.
- What post processor are you using with Fusion 360.
- Are you using the free/personal version of Fusion 360?
Edit: Just to be clear, this kind of problem can have a mechanical, electrical, or g-code (feed rate too high) cause. Collecting the above will help figure out the cause in your case.
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It is a build I bought from someone a week ago, who I can’t get ahold of, he seemed like an honest guy and he was selling as he sold his house and is moving
CNC Machine: V1 Engineering Lowrider2
Designed using: Free version of Fusion 360
FILE Type: .gcode
LCD Screen: Reprap Discount
LCD Software: Marlin Debug 2.0
Post processor: https://github.com/guffy1234/mpcnc_posts_processor
Can you share a bunch of pictures? Especially of the control board and the wiring?
Those pictures were great. It looks like you have a mini-rambo and series wiring.
I am curious about your leadscrews though. I suspect that is a 1 start leadscrew. Try putting a piece of tape on it and jog it down 2mm. If it spins a full spin, it is a 1-start. 1/4 and it is a 4 start. Also, make sure it is moving 10mm when you command a 10mm movement.
On which screw?
Those are the long screws and I have one on each side of the table correct?
I’m not sure if this helps answer the first question but yes I confirm it moves 10mm when asked to move 10mm
It is hard to tell, but that is a 4-start. So that should be fine.
Any other ideas?
In the configuration, there is a max feedrate or max speed. Check that the Z isn’t any higher than 10mm/s. When you change that, you have to save it with the “save to eeprom” setting.
There is also another post processor you can try. Fusion made it hard to automatically output Z feedrates that are separate from XY in the free version, but @Flyfisher604 has been working on another one that decides when you are moving in Z and drops the speed.
You can find a reference to the new post processor for Fusion 360 in this topic.
The fact that only one side is behaving badly leads me to believe this is not the issue, but it is something that should be checked out.
I believe fusion 360 free version default is 300mm/min I had set it to 1500mm/min
I’m not following the eprom part so I may have to change this setting elsewhere
I changed it in
-Actions
-Post Process
-Properties
-Job Travel Speed Z: 150
You can set the max feedrate in g-code. The setting uses mm per second, rather than mm per minute like other tools. You would need a G500 to save the setting so that it does not need to be added to each g-code file:
M203 Z8 M500
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Could you go in more depth I’m very new to all this, I also have a MacBook if this changes anything. I just downloaded the new post processor you sent me. Should I do anything in settings before I try it?
If you are using my post processor I would highly recommend viewing the documentation that describes the parameters. Many parameters are set so as to make as few changes as possible to what F360 is directing. Only if you enable options does the PP start changing things. To follow @jeffeb3 suggestion look at the Feed parameters and enable Feed: Scaled Feedrate.
Documentation is found at https://github.com/flyfisher604/mpcnc_post_processor
Marlin processes g-code files. This is the kind of files the post process in Fusion 360 produces. Besides making cuts, there are a lot of other things you can make Marlin do by sending it g-code. You can find the Marlin g-code reference here. So the M203 Z8 sets the max feedrate for the Z axis to 8mm/s or 480mm/min. This code can be executed anywhere you run g-code. If you are using a display with an SD slot, you can put it in a file and then run the file like you would do if you were milling something. If you are using a g-code sender like Repetier-Host, the manual tab has a place to type in g-code. commands.
Backstory on Fusion 360: Back in October of '20, Autodesk placed new restrictions on the personal/free versions of Fusion 360. One of those changes is to prohibit rapids (rapid movement commands) for CAM. The result is that movements for XY and for Z that were separate before were now handled all at once and at whatever feedrate was set for XY movement. Because of the lead screw, the LowRider cannot move as fast in the Z direction as it does in X and Y. The result is that post processed Fusion 360 g-code was attempting to move Z faster than it could resulting in lost steps. The g-code above places a limit on how fast to move on the Z axis, mitigating the issue.
Don has done a bunch of work on the Fusion 360 post processor that works around the problems introduced by Fusion 360’s restrictions as well as address other issues that I did not even know the post processor had. I recommend you make the switch to his post processor.
The thing that makes me think that the problem is not the Fusion 360 issue is that the problem only happens on one side. It is possible there is more friction on one side than the other, so more steps are lost in rapid movements on that side.
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