Strange behavior after recalibration

[noahcoleman]

I began recalibrating by resetting all the adjustment screws to the default position shown in the manual. I also changed the Horiz. Radius to 130 as per geneb's suggestion. After getting the Z tower properly calibrated, I moved on to the Y tower, but I have loosened the screw almost to the point of it coming out and it is still 1-2 mm off the platform. Should I just install longer screws? That seems like a bit of a bandaid...

[mhackney]

There is something very wrong. You measured the distance from the top plate to the end stop yesterday. Those values were all very close. I would expect the 3 screws to be adjusted to very similar lengths. Can you step back and take a photo of all 3 switches sort of looking up from below with the the carriage bolts just touching them?

This angle but with the carriages moved up:

[img]http://mhackney.zenfolio.com/img/s7/v15 ... 6889-4.jpg[/img]

And a similar one looking down at the base.

[noahcoleman]

Mhackney- are these good?

[mhackney]

Yes, which one is Z in the top photo?

[noahcoleman]

the one in the middle of the picture, just to the left of the ezstruder

[KAS]

Just an observation, do the arm ends have a measurable offset from center or does it matter if they are miss-matched when installed? Looks like a little hump on one side and flat on the other. ( in the pictures above)

[mhackney]

Ok, mechanically things look fine and if the measurements you reported for tower length are even in the ballpark (which I think you measured them correctly) then I question your calibration procedure.

Here's what I'd like you to do...

1) Leave the delta radius set to 130

2) Adjust all 3 end stop screws so they are the same length and lets say about 1/2 sticking out

3) Home the printer

4) Find some small thing (wood, plastic, metal) that is about 1cm high or so. A soda bottle lid would be fine.

5) Now manually jog down using the Z jog until you are just touching the top of the thing (soda bottle lid). (what control software are you using? they all have the ability to jog)

6) In the gcode entry field enter "X-77.94 Y-45" and hit return. Once the print head moves to the base of the X tower, try to slide the bottle cap under the nozzle. Estimate to the nearest MM how far the tip of the nozzle is from the cap (+ is a gap above the cap, - means you can't get the cap underneath). Report the Z "gap".

7) now enter "G0 X77.94 Y-45" and hit return. Do the same measurement at the Y tower and report it.

8) now enter "G0 X0 Y90" and hit enter. Do the same measurement at the Z tower and report it.

[mhackney]

I see what you are saying CAS, I marked it in red arrows:

I never had these arms but I don't think that little difference would matter that much. I would think you would want them all oriented the same though.

[noahcoleman]

I am using MatterControl, btw. Here are my measurements:
X Tower: +1mm
Y Tower: 0mm
Z Tower: -1mm

I will also switch those arms around now. Now that I've seen it, I can't unsee it.
Thanks everyone for your help!

[Mac The Knife]

When I first built mine, I had problem with not being able to calibrate my similar to your problem. I tracked the problem down to the bolts for the towers being loose.

[noahcoleman]

Well, that's definitely part of the problem. The top bolts on the z tower were loose. Now to retry calibrating...I'll update as soon as I'm done.

[mhackney]

Noah, the fact that all 3 of your measurements above are within very close tells me that you must be doing something wrong calibrating and the mechanics of the machine are in the ballpark. What I had you do was a very course calibration check. Actually, from your results, you could adjust the X endstop screw to make it SHORTER by 1mm and the Z screw LONGER by 1mm. Since these are 8-32 screws, 1 full turn will be .79mm. You might try that first, turn X and Y 1 full turn and then recheck. This is not going to address the delta radius but you'll start to see how these settings interrelate.

[noahcoleman]

I just found the error, and I feel really dumb. Backstory: after the first calibration, I accidentally deleted my macros. No big deal, because I've already calibrated. So, I have to recreate the macros, and to do that, I copy and paste from the manual to save time. So here's where I make my mistake--I copied and pasted from the WRONG LINE in the manual, where it says to send the machine to G0 Z5 X77.94 Y-45. Thats right, for the x and y towers, I have been trying to calibrate it while z=5. So, hopefully a quick calibration and I'll be off to the races again. Thanks for everyone's help and support.

[mhackney]

Where should I send my bill?

Just kidding, at least the mystery is solved. I love a good mystery but it does almost always comes down to operator error of one form or another. I'm as susceptible as the next guy in that respect. I try not to make the same mistake twice though, preferring to move on to bigger, more expensive, mistakes!

[bot]

This has been very entertaining, thank you!

[cyber.shifter]

I'm going to have to check the above things when I get home to my machine. I'm hoping I have the same problem, and it isn't something more serious.

[cyber.shifter]

I'm checking out my cheapskates now, seems the X-axis was a little tight. I'm going to run through all of them though. On a side note, Geneb, I just realized that it was you in the cheapskates checkpoint video. lol!

[geneb]

Yeah, I get around a lot.

g.

[cyber.shifter]

Ok, so I partially disassembled the towers. Took it down to just the cheapskates, no belts. Adjusted them all to what I thought was the same resistance. Then reattached the belts and did the same. Set my horizontal radius to 130 and start calibration from square one. Got it calibrated, and now the nozzle is only slightly off-center, but in the opposite direction. Still along the X-axis though. Z-axis end-stop screw is slightly higher than the other two, but not as bad a difference as before. Any suggestions?

[Mac The Knife]

Ok, so I partially disassembled the towers. Took it down to just the cheapskates, no belts. Adjusted them all to what I thought was the same resistance. Then reattached the belts and did the same. Set my horizontal radius to 130 and start calibration from square one. Got it calibrated, and now the nozzle is only slightly off-center, but in the opposite direction. Still along the X-axis though. Z-axis end-stop screw is slightly higher than the other two, but not as bad a difference as before. Any suggestions?

Start printing something!!

[cyber.shifter]

That's what I thought too! So I started the big print that I hadn't been able to get moving yet. Got about three layers in and the nozzle jammed, best I can tell.

Layer 3 of Katrina

I noticed that on the first layer the machine had trouble printing the perimeter lines at the extremes of the X-axis. I guess I should have stopped it, but I wanted to see how it would go, since the model didn't need to be perfect anyway. As soon as I can get back to the machine, I'll put up my EEPROM settings. Maybe there is something I'm not seeing.

[cyber.shifter]

Here's my EEPROM settings.

EEPROM Config