RepRap Community, Working on a reprap that has been out of commission for around a year. People have poked it, tried to get it to run, but to no avail. The issue is when a print starts, the part homes then starts printing. I press the home button in Pronterface and there is no issue. When I start a print, however, the part homes X and Y, then does Z. When it touches the Z end stop, the Z motors then squeal to move up, then squeal to move down. I have decreased the max acceleration and feed rates for the Z down to 50 mm/s^2 and 5mm/s to no avail. The motors will still go to a speed faster than the max feed rates. One experiment I found was that if the steps/mm was reduced to half rate (6400/1.25 steps/mm to 3200/1.25 steps/mm), the motor did not have an issue. It did move extremely fast in Z home section where the motors squeal, but obviously I cannot have the steps/mm wrong. Anyone know where I can change the Z feed rate in the homing command? Or where the homing command is located? I took the old firmware, tested it, downloaded the new firmware, tested that, transferred over steps/mm constants, and did a few other tests and bug fixes to get this thing to work, but I can't crack this bug. This same software is on 4 other printers that work without issue. This printer is unique in this bug, and has been left to rot in the corner as a result. I want this thing to live and do its job. EDIT: I also got new drivers for it today. No change. https://reprap.org/forum/read.php?4,359981,359981#msg-359981 Sun, 19 Jul 2026 17:16:34 -0400 Phorum 5.2.23 https://reprap.org/forum/read.php?4,359981,361939#msg-361939 https://reprap.org/forum/read.php?4,359981,361939#msg-361939
It is a patch solution. Not the type of solution I wanted though.]]> BlenderGuy Reprappers Wed, 28 May 2014 22:20:36 -0400 https://reprap.org/forum/read.php?4,359981,360817#msg-360817 https://reprap.org/forum/read.php?4,359981,360817#msg-360817
It is a really patchy solution.

I do not have an LCD controller on the board, but there is one in a cupboard. It is a future plan... I know, added complexity.]]> BlenderGuy Reprappers Mon, 26 May 2014 21:12:42 -0400 https://reprap.org/forum/read.php?4,359981,360409#msg-360409 https://reprap.org/forum/read.php?4,359981,360409#msg-360409 Schultz Reprappers Mon, 26 May 2014 00:19:00 -0400 https://reprap.org/forum/read.php?4,359981,360390#msg-360390 https://reprap.org/forum/read.php?4,359981,360390#msg-360390 Sublime Reprappers Sun, 25 May 2014 21:52:58 -0400 https://reprap.org/forum/read.php?4,359981,360384#msg-360384 https://reprap.org/forum/read.php?4,359981,360384#msg-360384
What happens is the printer homes the X, the Y, then the Z. After that, the carriage is moved in the Z, a short amount of plastic is retracted by the nozzle, then the carriage is lowered to the first layer height (0.35mm). After that, the machine moves to the starting location.

The issue is the second part, after homing, where the carriage moves up and down. That section is where the feed rate is too high. I do not know what that feed rate is. I do know that if I reduce the steps/mm to half of what it is, the motors move very quickly in that section, but then the rate is wrong for the rest of the print. I do know that this occurs on two separate systems using the same, brand new downloaded and old versions, of Marlin. With Sprinter, the system does this same motion, but slower and does not have an issue. I would like to use Marlin on this system as we desire to have a screen on the machine, something Sprinter cannot do.

I did get the second printer printing with Sprinter, but there is some odd extruder feed rate issue. It takes a long time to extrude filament, despite changing the constants to 10x the original feed rate for E. I boosted it from 30 to 300 with no change, but that is a different issue that I don't want to get into here.]]> BlenderGuy Reprappers Sun, 25 May 2014 21:06:38 -0400 https://reprap.org/forum/read.php?4,359981,360382#msg-360382 https://reprap.org/forum/read.php?4,359981,360382#msg-360382 Andrew Smith Reprappers Sun, 25 May 2014 20:51:17 -0400 https://reprap.org/forum/read.php?4,359981,360377#msg-360377 https://reprap.org/forum/read.php?4,359981,360377#msg-360377
Anyone know what that last Up/Down that occurs after Home when a print starts is called? I don't know how to search for the term.]]> BlenderGuy Reprappers Sun, 25 May 2014 20:11:44 -0400 https://reprap.org/forum/read.php?4,359981,360370#msg-360370 https://reprap.org/forum/read.php?4,359981,360370#msg-360370
I will be trying to use Sprinter instead of Marlin. I will report what I find.]]> BlenderGuy Reprappers Sun, 25 May 2014 18:59:33 -0400 https://reprap.org/forum/read.php?4,359981,360325#msg-360325 https://reprap.org/forum/read.php?4,359981,360325#msg-360325
Looking at it closer, this is what happens:

1. Home X
2. Home Y
3. Home Z (this is doing as is expected)
4. Move up in Z rapidly (And buzzing)
5. Move down Z to the first layer height rapidly (and buzzing)

When it is doing the rapid motion, it moves quickly, then buzzes. This does not move consistently, so it sometimes slams into the table or prints in air.
So it is something else. I will be looking through the config files again]]> BlenderGuy Reprappers Sun, 25 May 2014 16:25:54 -0400 https://reprap.org/forum/read.php?4,359981,360281#msg-360281 https://reprap.org/forum/read.php?4,359981,360281#msg-360281 BlenderGuy Reprappers Sun, 25 May 2014 15:10:08 -0400 https://reprap.org/forum/read.php?4,359981,360036#msg-360036 https://reprap.org/forum/read.php?4,359981,360036#msg-360036 Andrew Smith Reprappers Sun, 25 May 2014 03:32:12 -0400 https://reprap.org/forum/read.php?4,359981,359981#msg-359981 https://reprap.org/forum/read.php?4,359981,359981#msg-359981
Working on a reprap that has been out of commission for around a year. People have poked it, tried to get it to run, but to no avail.

The issue is when a print starts, the part homes then starts printing. I press the home button in Pronterface and there is no issue. When I start a print, however, the part homes X and Y, then does Z. When it touches the Z end stop, the Z motors then squeal to move up, then squeal to move down.

I have decreased the max acceleration and feed rates for the Z down to 50 mm/s^2 and 5mm/s to no avail. The motors will still go to a speed faster than the max feed rates.
One experiment I found was that if the steps/mm was reduced to half rate (6400/1.25 steps/mm to 3200/1.25 steps/mm), the motor did not have an issue. It did move extremely fast in Z home section where the motors squeal, but obviously I cannot have the steps/mm wrong.

Anyone know where I can change the Z feed rate in the homing command? Or where the homing command is located?

I took the old firmware, tested it, downloaded the new firmware, tested that, transferred over steps/mm constants, and did a few other tests and bug fixes to get this thing to work, but I can't crack this bug. This same software is on 4 other printers that work without issue. This printer is unique in this bug, and has been left to rot in the corner as a result. I want this thing to live and do its job.

EDIT: I also got new drivers for it today. No change.]]> BlenderGuy Reprappers Sat, 24 May 2014 21:17:57 -0400