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Re: Jammer's Ord Hadron build - Help Appreciated

PostPosted: Tue Nov 19, 2013 1:03 pm
by flickerfly
Oh yeah, I'd forgotten I'd shared that with you. :-) Glad to be a part of the success!

Re: Jammer's Ord Hadron build - Help Appreciated

PostPosted: Wed Nov 20, 2013 7:42 pm
by jammer
A question about setting the Z-Axis zero. Do I set it with the nozzle touching the glass bed or a certain height above the bed?

Re: Jammer's Ord Hadron build - Help Appreciated

PostPosted: Wed Nov 20, 2013 7:50 pm
by flickerfly
The easiest solution I've been given is to put a piece of typical paper between the glass and the hotend nozzle. It is about right when it mildly resists movement. Test all four corners. That's my leveling routine. I level at where it settles after homing Z.

Re: Jammer's Ord Hadron build - Help Appreciated

PostPosted: Wed Nov 20, 2013 8:45 pm
by jammer
flickerfly wrote:The easiest solution I've been given is to put a piece of typical paper between the glass and the hotend nozzle. It is about right when it mildly resists movement. Test all four corners. That's my leveling routine. I level at where it settles after homing Z.



Thanks! That is exactly what I was looking for. Will give that a try. I am thining this initial bed leveling is going to take longer than I think it will. :shock:

Re: Jammer's Ord Hadron build - Help Appreciated

PostPosted: Wed Nov 20, 2013 8:55 pm
by flickerfly
If you have some good springs on all four corners, I'd say tighten them down, find the highest corner and bring the rest up to that corner. Make sure you have some means by which to discourage the nuts under the bed from wiggling loose. In my experience, those two things mean you won't often have to re-level the bed. I've been using some blue-tack (tacky stuff for holding posters to dorm walls) on my nuts and that seems to hold them in place well. Eventually I'm going to try some nuts with nylon rings inside, but I haven't sourced them yet.

Re: Jammer's Ord Hadron build - Help Appreciated

PostPosted: Thu Nov 21, 2013 1:48 am
by jammer
I do have the springs recommended from McMaster-Carr so that sounds good. How tight should they be?

Re: Jammer's Ord Hadron build - Help Appreciated

PostPosted: Thu Nov 21, 2013 3:14 am
by flickerfly
I have scrounged springs from some paper printer I took apart, but I put as much tension in as possible so they are all the way down. ymmv

Re: Jammer's Ord Hadron build - Help Appreciated

PostPosted: Thu Nov 21, 2013 3:35 am
by jammer
flickerfly wrote:I have scrounged springs from some paper printer I took apart, but I put as much tension in as possible so they are all the way down. ymmv



OK, Got it. Thanks!

Re: Jammer's Ord Hadron build - Help Appreciated

PostPosted: Sat Nov 23, 2013 4:32 am
by jammer
Leveled out my bed and found out that there must be a trick to applying kapton tape to the glass without bubbles or wrinkles.

The other issue I have is that after leveling the bed I would set the z-axis to 0 with a sheet of paper between the glass bed and the nozzle. Everything looks fine with the home being manually set in the z-axis. When I load the calibration cube and press the print button in repeater-host, the nozzle homes and presses down on the bed and then tries to print the first couple of layers with the nozzle on the glass. Needless to say the ABS gets built up around the nozzle.

Any ideas why when the home is set that it would try to lower then nozzle below the surface of the glass bed when it starts printing?



UPDATE: I might have found the reason for the z-axis issue where the extruder was trying to drive through the bottom of the bed. Not sure why I did it but the z-axis steps per mm was set to 4096 when it should have been 2560. I will try again tomorrow when I have time to see if that helps.

Re: Jammer's Ord Hadron build - Help Appreciated

PostPosted: Mon Nov 25, 2013 5:40 am
by jammer
Ok guys,

I think I have figured out the z-axis trying to drive the hotend through the bed. My z-axis endstop was set just below the bed height. I mistakenly thought that by manually moving the hotend to .1mm above the bed and setting it to zero in Repetier Host that that would override the z-axis min endstop but I think when the Home All command is sent in G-code that the z-axis is being driven until it hits the min endstop. I have disabled it in the firmware and disconnected it from wiring. I will reconnect it after I get the printer working and can print out a fine adjusting bracket for my endstop.


My other issue that I have been researching tonight is that my z-axis motors sometimes don't move and just emit a loud buzzing sound. Sometimes it is just the one on the left and sometimes it is both. I have noticed that the left z-axis leads crew looks a little bent since it wobbles slightly when it is being turned. I have the z-axis motors wire in parallel. Do I need to increase the current on the driver for the z-axis? I have looked for procedures on how to adjust those but can't find anything specific other than to turn the pot on the driver while the motors are turning. Any suggestions? Should I rewire them to be wired in series?