Myke's Spare Parts Printer

[mykepredko]

As promised, here is an update on where I am with my printer. I’m making some good progress but I have one weirdness regarding leveling and the BL Touch firmware that I want to understand so please read through to the end and let me know if you have any comments.

Obviously cable management is next on my list of priorities, but everything moves as it’s supposed to and the movement is quite quiet; it’s at least as quiet as any of my other printers.

It was a great decision to use TMC2209s with sensorless homing rather than put in microswitches. That simplified the wiring somewhat and the end points are very easy to set and adjust - in the first of the two gantry end images below, the two position block in the X-Axis V-Slot rail is the endpoint that the extruder encounters when it’s at the end of its travel. The position repeatability is very good and seems to be on the order of microswitches.

The printer has had the X/Z-Axis gantry ends significantly redesigned to provide more rigidity - they’re now much smaller with additional ribs to minimize flexing.

The X-Axis stepper motor was moved to the right side of the printer to simplify eventual cable routing as I mounted the controller and power supply on the right side of the printer’s frame. This position put the controller’s USB “B” connector, Thumb Drive USB “A” connector and TF Card slot on the top of the printer for easy access.

They could have mounted them on the left side of the frame but this would have made accessing the controller’s connectors more difficult and would have had wires falling into the build area during debug (ie now).

PROBLEM/ISSUE/QUESTION:

I just completed wiring in the BL Touch and updated the firmware to support it.

The printer does seem to autolevel (9 x 9 mesh) but I don’t get any feedback as the result except the BL Touch is flashing red after the operation. I was expecting to see the display update to indicate that the autoleveling was executing and when it was complete, give me some idea of the status of the result. Maybe the flashing BL Touch unit is my indication, but I was expecting something more that would be helpful.

The instructions I’m using for setting up the BL Touch are found here: 3D Touch on a Robin Nano V3 These instructions indicate that I should see some kind of message on the screen and doesn’t say anything about a flashing BL Touch after the operation is complete.

I’m doing the autolevel on the bare aluminum heatbed surface - I was planning on starting with a PEI sheet and then going to glass (of some type). If you look at the first image, that was taken when I was measuring the offsets for the BL Touch and I put on a piece of blue tape with a black dot - this was taken off for this testing.

I did try the Autolevel (G29) on Pronterface and the results I got are:

g29
SENDING:G29
Bilinear Leveling Grid:
0 1 2
0 -0.268 -0.140 -0.105
1 -0.123 +0.005 +0.070
2 -0.247 -0.193 -0.203

Now, could I have lucked out and have a heated bed that is quite flat (I know it isn’t completely flat as when I put a straight edge on it, I can see and hear it rock a bit) as well have put together a very square printer (I have been worried about this and I have been making sure of all the right angles in the printer).

Thoughts? Am I lucky or is my firmware image not correct and the errors are being hidden from me?

Thanx!

myke

[Glenn]

in the BL touch documentation, it tells you the error the flashing duration is indicating but it can only indicate a wiring problem or time out, like if the probe didn’t retract in time but it does have a timing chart that might tell you something. on mine usually, I get a message that the mesh is complete and unprobed parts for the bed are auto-filled and asks to save the mesh to available save locations.

[mykepredko]

Thank you - I think from what I’m seeing the mesh operation is complete.

I’ll look for the documentation and see what I can figure out.

[mykepredko]

Found the problem it was an incorrectly wired white/black connector. I reversed the polarity and Bob’s your uncle, no more flashing.

If anybody is looking for the BL Touch manual, here it is: BLTouch: Auto Bed Leveling Sensor for 3D Printers

Now, after I run the tests, the BL Touch is red all the time but that seems to be normal. I found:

1. BL touch sensor always red. Yes I’ve tried looking for reasons why

2. Creality BL Touch Kit - Help Please

There’s also: Bltouch Red Led Mod (Please excuse the capitalization) in which the always on Red LED is removed from the BL Touch and put somewhere else.

Any comments? The BL Touches that I have used before were not genuine Antclabs (el cheapos from AliExpress) which don’t leave the red LED on all the time.

[Glenn]

mine are on all the time too. there is also a faint blue LED in there too

[kitedemon]

Mine alternated blue to red to b loo during probing then it is red while the probe is not deployed.

[mykepredko]

@Glenn & @kitedemon

Yes, I’m seeing red all the time as well.

Somewhat disconcerting as I think of “red” as being a problem - especially since I had the flashing read before.

Thank you for your answers.

[Jason]

Red constant is normal, Flashing red is bad. Actually just finished this section in my book about BLtouch Way to much technical reading about a “little poky thing with a stick” as I have once heard it described.

[mykepredko]

Thanx for confirming the constant red light coming from the thing. Definitely not intuitive to have red on at any time there isn’t an error.

You should also note in your book that some clones, ie this one:

Do NOT have a constantly on red LED.

Good luck on the book - I know what a grind they can be.

[Jason]

Thanks for the info,

I have tried to cover most of what is well documented, I have kind of noted that there are others out there that do not fall under the same rules and operation.

I have come to the conclusion that its going to be impossible to cover everything although I would like to, I’m gonna try to keep it under 350 pages. Its gonna be a bit of a beast but lots of troubleshooting in it.

[Glenn]

the yellow tape at the top is significant to the accuracy of the unit. I see yours is coming loose.

[mykepredko]

Huh. That might explain some things. I have to autolevel that printer a lot - I thought there was a mechanical/stepper issue.

How do I go about fixing it?

Thanx!

[Glenn]

To be honest I don’t think this is the issue I think it was something to do with heat causing the magnetic field to slightly change and varying the accuracy of the sensor and that strip of yellow was the fix for it.

On my printers, if the motion of the sensor isn’t a flat plane it can’t level the bed properly. so the X-axis is a factor because the sensor is attached to it and the ends of the x-axis are defined by the vertical parts… being made like the Creality printers with 2 vertical columns mine could be knocked out of parallel, it happens frequently (if I move the printers) that I have to put it back parallel before it’s effective again. it has the effect of the X-axis sort of twisting and making the Sensor corkscrew slightly so it can’t tell what level is. I know your printer is more of a box but maybe there’s an idea in there somewhere that might expose your issue?

[mykepredko]

This sensor was added to a Two Trees Sapphire Pro (core XY printer). It’s a pretty rigid box.

I think what you’re saying is that the sensor has to move in a flat plane that it’s perpendicular to - I can confirm that’s the case.

It’s about three years old - maybe it’s just worn out?

[Glenn]

@mykepredko

I think what you’re saying is that the sensor has to move in a flat plane that it’s perpendicular to - I can confirm that’s the case.

yes! sorry for being long-winded I think I’m in my 26th hour and starting to get spacey

[mykepredko]

First Prints!

I’ve been working on cable management for the past few days and I have the Y-Axis and the hard part of the X-Axis done - from the front, the printer looks pretty good:

With everything moving well and with no possibility of cables getting in the way, I decided to try a couple of prints. As the printer is set up like an Ender 3, I used the default Ender 3 Cura profile and doing a calibration square and a Benchy, I got:

I discovered I only had an old spool of blue PLA in a dry box and as I used blue painter’s tape as the print surface, I’ve removed the centre strip in the photographs above to provide some contrast in the image between the prints and the printer.

Personally, I’d rate the calibration cube as 4/5 - I think the extruder is producing a bit too much material, the Z-Axis offset needs a bit of calibration as the bottom is flared out and the rear sides (to the right of the “Y” in the picture above) aren’t square and maybe have too much material (which I think means adjust the EJERK value or enable S-Curve Acceleration).

For Benchy, it’s actually quite good - the two major flaws are the flared bottom (same as the calibration cube) and a horizontal line in the print that you can see by the front right opening in the bow. I’d give it at least a 4.5/5 as it’s better than what I usually see for first print samples by other printers (it’s definitely better than the first one I did with my Sapphire Pro).

In terms of the quality issues, my personal feeling is that I need to try some PLA that hasn’t been hanging around for a year or more as well as some ABS and/or PETG before I start tweaking values.

I should also point out that I’m acknowledging that the good results are a result of the Swiss Made hot end and Robin Nano V3 - those are pretty high end parts.

Now to figure out how to clean up the rats’ nest at the right rear of the printer:

But, I’m pretty pleased with where things are at.

[Jason]

Hats off to you, very impressive first prints.

[mykepredko]

Thanx @Jason!

I was pretty stoked when I saw the calibration cube so I decided to go ahead with Benchy.

The plan is to nail the remaining flexible conduit while tuning the printer and trying some other materials.

[mykepredko]

Good Saturday everybody.

I just wanted to post that I’ve reached what I consider to be the completion of the first part of my spare parts printer project.

You can see a write up of it here: Myke's Spare Parts 3D Printer by mykepredko - Thingiverse

It works quite well - I’ve run it for about 30 hours now and I’ve gotten some interesting prints from it:

There’s some work to do to get everything best in class, but I’m quite happy with where things are.

If you look through the Thingiverse write up, you’ll see that I put in expected prices for the various parts - As I was literally building this from my stocks of various parts I never realized that this would cost somebody $1,000 CAD if you were starting out from nothing.

Thanx for everybody’s support. There are a few things I want to work on with this printer, but I think it’s at a pretty good place.

[Jason]

Nice job, Good to see it come to completion. Kudos to you.