Just finished assembling my 8200 and am unable to successfully print yet due to these issues:
1a. During manual bed movement (via Repetier), I see no skips, but during printing it skips and seems to bind on something ( I hear a thunk noise). I’ve watched it closely during print, and don’t see anything obvious. This is with small prints in the middle of the bed, not towards the ends (although I did verify no interference among the bearing mounts on the ends). I did notice that the Y-axis belt is VERY tight. I verified the teeth count 3 times before cutting, but it’s a super tight fit.
1b. Additionally, I see some X-axis skipping, but that movement is silky smooth even when turning the motors off and moving it. I’ve verified that the rods are parallel. Moved both directions by hand, and messed with the tightness of the bearing holders. Example print is below (the “blob” is home, for orientation purposes):
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The microswitches are sloppy. I know they are cheap to keep the cost of the kit down, but I routinely have issues with the Y-axis endstop switch lever hitting the edge of the adjustment screw and allowing the screw to pass by the switch lever. It appears to vibrate during bed operation and there’s a good bit of lateral slop in the lever. Any ideas?
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Z-axis threaded rod was bent out of the box. It doesn’t seem to affect movement much (although there is significant “wobble”. I plan to replace the rod with a locally procured one and (when I can finally print) upgrade the Z-motor mount.
For the Y end stop: the 2 wires that are attached to the Y end stop, Make sure they are not rubbing against anything.
I put a cable tie on mine.
Check the belts make sure they are not to tight or to loose.
Check the pulleys for the belts on the motors make sure they are tight (mine were loose and they made noise)
The voltage reference for the motors set them to 0.55.
Make sure all of the rods are clean and oil them.
Rods were all oiled. I just pulled the belts and tightened the pulleys. Only could get maybe another quarter turn on the set screw, but did. Just put it all back together and running a test print now… :crosses fingers:
No joy. Still exhibits the same symptoms. Belts are tight, pulleys are tight, no visible binding that I was able to see, motors were checked for shorts, I metered the motors and got ~3ohms per pair (pin1-pin2, pin3-pin4). Would overvoltage cause this? The motors are being fed .65 -.88 VDC, but I can’t seem to get the pots to turn to trim them.
Make sure you have a small enough screw driver to fit in the pot.
You should set the voltage to 0.55.
Going higher will make the driver cards heat up and skip steps.
The belts need to be tight but not to tight (this will make them bind)
Got it, thanks. Was trying to use a Phillips head. Changed out to a 1mm straight tip and got the voltages down. Still concerned the belt may be too tight, but we’ll see. I’ll order another belt just to have on hand and hopefully this print comes out!
Hi ntwrkguru,
if you need a bit of tolerance in the belt length, you can put springs on the belts so that they will not immediately loose tension. An example how this can look like is shown in this post. The springs have to be bent a little on both ends so they don’t slide of the belts on their own, but it can be done with normal clothes pin springs.
Cheers,
kuraasu