I’m getting some small vibrations when moving. Straight X and Y movements don’t seem too bad, but diagonal movements amplify the vibration. Attached are some pics.
What do I need to look at or try to adjust to get the movement to be more smooth?
Loosen the roller tension bolts, draw on a smooth surface, lighter pen pressure.
Diagonal line = two motors running at the same time, the most obvious is voltage drop, if it’s ripple you would need a scope to find it.
I have read your other post about freezing, can you keep a voltmeter connected.
Tension bolts A and C were loose, but I did have B tightened so I loosened it. I was drawing on a smooth surface, but I may have been using too much pen pressure. Additionally, the pen was extending far below the mount so may have been a bit unstable. Correcting these issues did help things greatly, but there’s still a bit of vibration. Is it also possible I have the belts too tight?
Probably not the belt tension.
What board do you use? Did you flash your own version of the firmware? What are your microstepping settings? Will it do the same thing if you increase the speed?
Not the center bolts, the two on each roller.
Ramps 1.4 with A4988 drivers and 1/16th microstepping. (I’m going to order a set of DVR8825 drivers.) Ryan’s dual endstop firmware, only changes being to choose the stepper driver and steps/mm. I’ll have to experiment with speed.
Do you mean “tension bolts” A and C? Those are loose. B is now too. Those are the only bolts referred to as “tension bolts” in the assembly instructions. Or do you mean other bolts?
On the Rollers. There are two bolts on the rollers with plastic on both sides (on the top) they are probably far too tight.
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Thanks for the clarification. Sorry for being dense! I went out and checked those bolts and they were just snugged up, but not very tight. I backed off each one about a half turn anyway and there is a gap between the nut and the plastic. I didn’t get to run a test, but will report back when I do.
How much would the surface of the conduit play into it. It does seems to have a very rough texture. I’ve thought about making a file that would run it from X0/Y0 to Xmax/Ymax and back about 20 times and see if that helps break it in.
It just clicked with me that I never checked or set the stepper current.
I created a gcode file that would move the assembly from the front left corner to the rear back corner back and forth about 10 times. I ran that several times to try to “break in” all the parts.
I also read some of Ryan’s posts about squaring the pen mount and mentioned what kind of pen to use. I think the pen I was using had a very loose fit in the “collet” so the tip of the pen wasn’t stable at all. We have a shortage of pens around the house for some reason (maybe kids have something to do with it), so I replaced it with a very fine tip sharpie. Still probably not the best, but at least the tip won’t be moving around inside the pen housing.
I also used a lot less pen pressure.
I also replaced the A4988 stepper drivers with DVR8825 drivers (and un-did the firmware modifications I had to make to use the A4988 drivers). I made sure to adjust the stepper current. All of the steppers, out of the box, were set pretty low.
Things are looking a lot better now!
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Nice!