No more than 24 file listed from SD with M20 command

Hi all, I have finished building my Ormerod yesterday and I have already printed some pieces (found no hard problems apart the bed leveling which is a tedious process, if done manually, or simply not working, if done automatically).

Now I have loaded a good number of gcode files I would like to test and I have found that when I issue the M20 command (or a click the SD->print function on pronterface) only the first 24 files (ordered by creation time) are listed.
Is anyone of you experiencing the same problem?

I'm using the latest firmware:
FIRMWARE_NAME:RepRapFirmware FIRMWARE_VERSION:0.57a ELECTRONICSuet DATE:2014-01-16

Thank you, Andrea.

Hi Andrea,

yes it's a known bug and imho already on the list for future revision of the firmware.

Markus

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XBee & electronics blog: [lookmanowire.blogspot.com]

Yes, it is limited to 24 files in firmware. It can be increased, and will be in a future firmware update. I don't know why 24 was chosen, though!

Ian
RepRapPro tech support

Thank you all!
Good, I will wait for a firmware update for this. I was worried about this issue being caused by an hardware problem. I am happy it is not the case.
Where are the know issues reported? I searched before posting, but I cannot find any info about it.

So my main remaining issue is the bed leveling. Tomorrow I'll dedicate the morning to leveling the bed by hand, because with the other methods (G30 or G32) I can't get a consistent result.

If you load my latest binary from [github.com], the file limit is increased to 42. I recommend you use Matt's web interface with it.

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

I suppose people could start logging issues on the Github issue tracker, it would be the sensible place, it just hasn't been used so far as we work on it internally: [github.com]

Ian
RepRapPro tech support

To get auto bed levelling working well using the original IR sensor, you need to avoid bright sunlight or incandescent light. Also use white tape or paper instead of the aluminium tape.

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

Quote
dc42
To get auto bed levelling working well using the original IR sensor, you need to avoid bright sunlight or incandescent light. Also use white tape or paper instead of the aluminium tape.

Does the paper/tape need to be underneath the kapton tape?

Quote
PaulHam
Does the paper/tape need to be underneath the kapton tape?

Only if you want to print right up to the corners where the tape/paper is.

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

Quote
dc42

Quote
PaulHam
Does the paper/tape need to be underneath the kapton tape?

Only if you want to print right up to the corners where the tape/paper is.

Except that you cannot put the tape on the corners of the glass. The tape must be offset in the -ve X direction due to the displacement of the sensor from the nozzle and cannot be at the Y edges because the head fouls the clips. So the tape/paper must be at 60mm from the edges in the Y direction and 20mm or so off the edge in the +X direction, which pretty much halves the print area if you cannot print over the tape.

Dave
(#106)

Quote
dmould

Quote
dc42

Quote
PaulHam
Does the paper/tape need to be underneath the kapton tape?

Only if you want to print right up to the corners where the tape/paper is.

Except that you cannot put the tape on the corners of the glass. The tape must be offset in the -ve X direction due to the displacement of the sensor from the nozzle and cannot be at the Y edges because the head fouls the clips. So the tape/paper must be at 60mm from the edges in the Y direction and 20mm or so off the edge in the +X direction, which pretty much halves the print area if you cannot print over the tape.

Dave
(#106)

Of course you can put tape on the corners of the glass. If you are still using foldback clips then I suggest you look at the photo frame clips that many of us are using instead. They only encroach the Y axis by 3mm at each end. I don't understand your point about offsetting the tape in the X direction. Sure, the sensor is offset from the nozzle, but sensor will still be able to determine the angle at which the bed tilts, which is what matters.

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

Quote
dc42
Of course you can put tape on the corners of the glass. If you are still using foldback clips then I suggest you look at the photo frame clips that many of us are using instead. They only encroach the Y axis by 3mm at each end. I don't understand your point about offsetting the tape in the X direction. Sure, the sensor is offset from the nozzle, but sensor will still be able to determine the angle at which the bed tilts, which is what matters.

With X axis at the physical end of its travel (end of the arm), my IR sensor is still 12 mm in from the edge of the glass - it cannot physically move any closer to the edge because the LU bearing is hitting the plastic part that holds the runner. It's not IMO a good idea to make your X set point closer than 3mm from the end-stop to prevent a collision in case the home position changes a bit (which it always seems to do after a G30 command, and it probably also changes a bit with different illumination levels around the X stop tab as well). To give a 10mm diameter target size and an end-stop margin of error the tape has to extend in by 12+3+5 = 20mm from the edge of the glass.

No, I haven't changed my clips yet, but then I am not using the automatic Z-homing or bed levelling because I am not finding it to be consistent enough.

Incidentally, when I tried out the automatic bed levelling command, while the head travelled to each of the 4 set points in turn, it only seemed to take measurements from the first two and the last point - although of course only 3 points are necessary, so I don't know why 4 are used in any case.

Dave
(#106)

Quote
dmould
With X axis at the physical end of its travel (end of the arm), my IR sensor is still 12 mm in from the edge of the glass - it cannot physically move any closer to the edge because the LU bearing is hitting the plastic part that holds the runner.

So what? The difference between X=53 and X=230 (which are the X-points I use for bed calibration) is plenty to establish the tilt of the bed in the x-direction.

Quote
dmould
It's not IMO a good idea to make your X set point closer than 3mm from the end-stop to prevent a collision in case the home position changes a bit (which it always seems to do after a G30 command, and it probably also changes a bit with different illumination levels around the X stop tab as well). To give a 10mm diameter target size and an end-stop margin of error the tape has to extend in by 12+3+5 = 20mm from the edge of the glass.

If you are printing on Kapton, you put the white tape or paper under the Kapton, then you can still print on that area. One concern is that the thickness of the tape or white paper affects the bed height at that point. So you need to use thin tape or thin paper. Even if you want to avoid printing over the tapes, you can still print e.g. a circular object almost 200mm in diameter.

Quote
dmould
No, I haven't changed my clips yet, but then I am not using the automatic Z-homing or bed levelling because I am not finding it to be consistent enough.

It's much more consistent with a modulated IR sensor.

Quote
dmould
Incidentally, when I tried out the automatic bed levelling command, while the head travelled to each of the 4 set points in turn, it only seemed to take measurements from the first two and the last point - although of course only 3 points are necessary, so I don't know why 4 are used in any case.

I used to use 4-point levelling, and the head did take a measurement at all 4 points. Currently I use 3-point levelling. But even if the glass bed is perfectly flat, 4-point levelling is useful unless you can guarantee that the two y-axis rods are exactly parallel. If there is a twist between them, then the amount of bed tilt in the x-direction will depend on the y-position.

---

Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

Quote
dc42
If you are printing on Kapton, you put the white tape or paper under the Kapton, then you can still print on that area. One concern is that the thickness of the tape or white paper affects the bed height at that point. So you need to use thin tape or thin paper. Even if you want to avoid printing over the tapes, you can still print e.g. a circular object almost 200mm in diameter.

I'm printing ABS, and found that printing on solvent cement gives the most consistent results (though other methods may also work, I have not done a great deal of experimentation after I found a way that was reliable). If the cement is applied over the white tapes it will probably affect the IR reading, so printing over the tape is probably not going to be possible.

Quote
dc42

Quote
dmould
No, I haven't changed my clips yet, but then I am not using the automatic Z-homing or bed levelling because I am not finding it to be consistent enough.

It's much more consistent with a modulated IR sensor.

Yes, that's a modification I plan on making - or perhaps a completely different arrangement such as a retractable Z microswitch - I want to get the Z homing to be automatic. I need to set up a firmware development environment, and I might then carry out quite a few changes. One thing I would personally like is completely standalone operation - adding a small display device with touchscreen or buttons to set up and start the print without needing a PC, and putting the print files onto a USB stick instead of the SD card. OTOH I may well end up getting a far more expensive machine for work now that I know filament printing will do what we want in principle, and using the Omerod at home.

Quote
dc42

Quote
dmould
Incidentally, when I tried out the automatic bed levelling command, while the head travelled to each of the 4 set points in turn, it only seemed to take measurements from the first two and the last point - although of course only 3 points are necessary, so I don't know why 4 are used in any case.

I used to use 4-point levelling, and the head did take a measurement at all 4 points. Currently I use 3-point levelling. But even if the glass bed is perfectly flat, 4-point levelling is useful unless you can guarantee that the two y-axis rods are exactly parallel. If there is a twist between them, then the amount of bed tilt in the x-direction will depend on the y-position.

That's a point I had not thought of. Although I really want to modify the bed so that it does not change, making automatic bed-levelling measurements unnecessary. I've beefed it up a bit, and now can usually get away with using a fixed bed compensation file, especially for small jobs, though I've become adept at taking the 4 measurements while waiting for the bed to heat, and can do it in a minute or so.

Dave
(#106)