Folger Tech Kossel 2020

Hello everyone,

It's been 3 weeks since I got the kit and I'm getting the firmware set up. I'm using Marlin Delta 1.6.4 from the Folger Tech website. I originally had an issue with the printer allowing movement at all. I went back and re-seated the thermistors to the board, looking at the build manual again to be sure where they hook up, and it worked. I can home out at the endstops just fine, I can get it to come down to Z50, just like it says to in the manual. But when I want to do the paper test to find MANUAL Z HOME POS, I cannot travel further than Z0 and I still have a long way to go to get to the plate. I plug in negative numbers but it will not travel there. The manual says I should subtract to find this position, but only by adding to that Z number can I even approach the plate. And what will I do if I keep that up and reach the top of the plate to obtain that number? According to the method they describe my number wouldn't be 403 which is larger than the build volume, by almost twice as much.Any suggestions would be appreciated.

Thanks,

Knicknac

I ran into the same issue. I had to increase this parameter from the original setting so I could follow the steps in the manual and get a correct value. I think I added 10mm to the original setting but you only need to add enough to get you "below" the bed, and was able to find my z home this way using the steps in the manual.

I am at work, if you need more information I can look into my own config.h and let you know exactly which line # I had to change.

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Knicknac
Hello everyone,

It's been 3 weeks since I got the kit and I'm getting the firmware set up. I'm using Marlin Delta 1.6.4 from the Folger Tech website. I originally had an issue with the printer allowing movement at all. I went back and re-seated the thermistors to the board, looking at the build manual again to be sure where they hook up, and it worked. I can home out at the endstops just fine, I can get it to come down to Z50, just like it says to in the manual. But when I want to do the paper test to find MANUAL Z HOME POS, I cannot travel further than Z0 and I still have a long way to go to get to the plate. I plug in negative numbers but it will not travel there. The manual says I should subtract to find this position, but only by adding to that Z number can I even approach the plate. And what will I do if I keep that up and reach the top of the plate to obtain that number? According to the method they describe my number wouldn't be 403 which is larger than the build volume, by almost twice as much.Any suggestions would be appreciated.

Thanks,

Knicknac

Have you installed all the jumpers underneath the Stepper Drivers?

Thanks for the reply guys. What I meant to say and didn't is that the change in parameter at line 346 is 453.9 before I can even attempt the paper test. That's way off of the number the manual says I should be at. The starting value is 253.9 and I'm supposed to subtract whatever number I use to get to the plate. I did install the jumpers. I even went back to check the orientation of the drivers and their power cords, all of that is correct. I thought, after reading posts for the last 2 days, that maybe the endstops were inverted, but I'm not comfortable changing those parameters. I was under the impression that the firmware downloaded from Folger Tech's site was pretty much configured and only basic changes would be needed.

It sounds to me that your steps/mm factor is too low by a factor of about 2. If you tell the printer to move the head down by 100mm, does it actually move down by only 50mm?

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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 didn't get an accurate measurement of that movement, but basically, yes. I give it a nominal new number and it does not move that much. I checked the lines of code for steps/mm and their correct for 36 tooth. (Am I thinking of that parameter correctly?) I thought last night that maybe i really have a 20 tooth pulley but not sure about that yet. I'm at work now though, so I can't dig in to it until later. I'm still trying to learn all the codes available to me too so I can get the machine to tell me where it actually is. Right now I'm taking very crude measurements with a tape measure to get aquainted with how the firmware works and responds.

I think your Z is actually direct driven of the motors (Looking at the photos on Folgers Web page) is which case number of teeth on the pulleys don't come into it.

What we would need to know is what leadscrew's they use on the Z Axis ie are they 5mm 8mm or even Acme threaded Leadscrews? if the latter then the number of start's and the pitch would also need to be known.

Doug

Edit

just looked at the Build instructions and they suggest that the screws are m5 in which case assuming the motors are std 1.8 deg stepper's and 1/16 microstepping then you Z Steps per mm should be 4000 (200 steps x 16 microsteps / 0.8 thread pitch)

Edited 1 time(s). Last edit at 06/11/2015 10:26AM by dougal1957.

The pulleys on a Kossel won't be 36 teeth, they are probably 16 or 20 teeth. I suggest you count the teeth and adjust the steps/mm. It will probably be 80 or 100.

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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].

When I went back and looked at the contents of the kit on Folger's site, it says they are 36 teeth, and I downloaded the firmware for 36 teeth. But i'll definitely count the teeth on the pulley and post my findings this evening. If it's 20 then I'll go back and get the correct firmware package too. @Dougal - there are no lead screws on this printer. It's belts and pulleys only. But I do appreciate the input, thanks guys.

I don't know the Folger Kossel kit. The reason I suspect the pulley has less than 36 teeth is that it would give poor vertical resolution, assuming standard 1.8 degree stepper motors, 16x microstepping, and a belt pitch of 2mm or thereabouts.

What steps/mm value do you have configured on the firmware?

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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].

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Knicknac
When I went back and looked at the contents of the kit on Folger's site, it says they are 36 teeth, and I downloaded the firmware for 36 teeth. But i'll definitely count the teeth on the pulley and post my findings this evening. If it's 20 then I'll go back and get the correct firmware package too. @Dougal - there are no lead screws on this printer. It's belts and pulleys only. But I do appreciate the input, thanks guys.

Yes My apologies I was thinking of the 2020 I3 that has just been released. And I would agree with DC42 re the pulleys you definitely need to count the teeth I have come across 15 16 17 18 20 tooth to name a few in fact my Prusa I3 was supplied with 17 tooth gears which really threw me for a while

Doug

Folger quit shipping 36 tooth sone time ago, choosing to standardize on 20 tooth pulleys for better resolution some time near late April early May. Get the 20 tooth download . . . the steps/mm Folger uses is 84, IIRC, which is damn close to dead-on, no matter what the 'use 80!' crowd may claim . . .

- Tim

Edited 1 time(s). Last edit at 06/11/2015 11:52AM by tadawson.

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tadawson
Folger quit shipping 36 tooth sone time ago, choosing to standardize on 20 tooth pulleys for better resolution some time near late April early May. Get the 20 tooth download . . . the steps/mm Folger uses is 84, IIRC, which is damn close to dead-on, no matter what the 'use 80!' crowd may claim . . .

- Tim

What is the pitch of the belt supplied by Folger?

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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].

@dc42 - They sent me a GT-2 belt.

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Knicknac
@dc42 - They sent me a GT-2 belt.

A GT2 belt has a pitch of 2mm. So if the pulley you have has 20 teeth, one revolution of the pulley moves the carriage 20 x 2 = 40mm. A rotation takes 16 x 200 steps assuming a standard 1.8 degree/step motor and 16x microstepping. So the correct steps/mm value is (16 * 200)/(20 * 2) = 80. This happens to be exactly the configuration (and steps/mm) that my delta uses.

84 steps/mm would be almost right if the pulley had 19 teeth (the calculation comes to 84.21).

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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].

Yet numerous folks have reported that 84 gives more precise motionon to the drives. Theory is a wonderful thing, right until reality shoots it in the face . . .

Why I don't know, but this has been verified - perhaps pulley diameter is a bit over. I do know that my parts are a smidge *undersized* running 84 on this printer, and that 80 would make it worse. Another user here in a different thread did motion measurements on all the axis on his, and verified that 84 is exact . . . . theory be damned, since the printer apparently can't read . . .

Myself, I'd start with what the kit maker has determined to be correct, and tune from there.

- Ti

Edited 1 time(s). Last edit at 06/11/2015 03:31PM by tadawson.

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tadawson
Yet numerous folks have reported that 84 gives more precise motionon to the drives. Theory is a wonderful thing, right until reality shoots it in the face . . .

Why I don't know, but this has been verified - perhaps pulley diameter is a bit over. I do know that my parts are a smidge *undersized* running 84 on this printer, and that 80 would make it worse. Another user here in a different thread did motion measurements on all the axis on his, and verified that 84 is exact . . . . theory be damned, since the printer apparently can't read . . .

Are you certain that you don't have 19-tooth pulleys, or a belt with a pitch a little less than 2mm instead of GT2? If the pulley diameter was a bit over, that would cause the belt to be a bad fit, but wouldn't affect the steps per mm. A full rotation of a 20 tooth pulley can't move a 2mm pitch belt by anything other than 40mm, unless the belt somehow slips a whole tooth - which would ruin the print.

My Kossel with GT2 belts and 20 tooth pulleys is set to 80 steps/mm. A 50mm test cube printed in PLA came out 49.8mm high, which is more or less spot on.

There are other factors which may affect the X and Y sizing, so it is the Z height that you should check to make sure you have the correct steps/mm.

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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].

As I said, I'm not certain why, and when I get my metal corners in and rebuild it (next week?), hopefully I can find out. It was specified to be 20 tooth and GT2 . . . but the mfg. also said to use 84 steps, so gotta take it with a grain . . .

- Tim

Edited 1 time(s). Last edit at 06/13/2015 12:10PM by tadawson.

I counted the teeth on my pulleys, they are indeed 20 teeth. I downloaded the correct firmware and successfully completed the paper test. I then moved to set up the auto leveling probe. While doing that I've developed a new problem. My Z axis motor is now locked up and when I try to move home it just makes this horrible noise like it's grinding and won't move at all. I can't even move it by hand. I'm hoping it isn't ruined or broken. Any ideas?

Won't move even with power off, and the belt loose? Dead motor, plain and simple . . . contact Folger, they will send you a replacement . . . If it moves without power, then likely it's something else . . .

- Tim

Edited 1 time(s). Last edit at 06/13/2015 12:13PM by tadawson.

Can you move the motor by hand when the power is off?

If yes, then the problem is probably a faulty cable or faulty driver rather than the motor.

If no, then remove the belt. If you still can't move the motor with the power off, then take the motor apart and remove the debris that is causing it to jam.

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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].

Hello again everyone,

I've been gone for a min. waiting for my metal corners, which I have installed, and I did receive a replacement motor. I have installed that as well. So, I'm back to where I left off basically, trying to configure everything. I just realized that my steps per millimeter must be off because I made an adjustment to be able to do the paper test and the nozzle does not move the amount I plugged in. In fact, I ran into the table. (And now I'm a little upset) I'm going to have to learn how that formula works and how to measure it. I'm working with a set of 6" calipers and a machined piece of small steel to get readings on movement. If you guys have any advice on how to get this thing configured, I'd appreciate any insight. I realize I'm going to have to supply more info. it's just late now and I'll be back at it tomorrow night.

I've seen a few posts about the metal corner pieces. I read one about the corner pieces not being 120 degrees. I agree with that guys post, don't they understand triangles or how to machine a 120 degree angle? It is kind of ridiculous, but then, they were only $50. Eventually, I'll be making my own and changing those.

Talk to you guys soon!

Knicknac

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Knicknac
Hello again everyone,

I just realized that my steps per millimeter must be off because I made an adjustment to be able to do the paper test and the nozzle does not move the amount I plugged in. In fact, I ran into the table. (And now I'm a little upset) I'm going to have to learn how that formula works and how to measure it. I'm working with a set of 6" calipers and a machined piece of small steel to get readings on movement. If you guys have any advice on how to get this thing configured, I'd appreciate any insight.

Talk to you guys soon!

Knicknac

First of you figure out which pulleys you got with your kit, 16 or 20 tooth, for 20 tooth pulleys it is 80 steps/mm and for 16 tooth it is 100 steps/mm, that is all you need to figure out about the steps /mm.
Then there are other parameters to adjust in the firmware before starting to print, but to get started there is good information in the configuration-manual.

EDIT: Also there is a good thread about this particular printer already in the "Delta"-forum: [forums.reprap.org]

Edited 1 time(s). Last edit at 07/25/2015 04:15AM by Koenig.

When did Folger ever ship 16 tooth? Tne older kits were 36, and then they went to 20 tooth . . . and I have not heard of any change, although folks could buy extra 16 tooth if they so chose. And 16 tooth would cause him to come up short, not hit anyhow . . .

Hitting the table may be nothing more than having the height parameter set wrong. When you just get to the table, what do you see as your height? And if you do have 20 tooth, 80 steps/mm *IS* correct - I run that and my dimensions are spot on . . . check height settings and microstepping . . . If you are using autolevel, make certain that your probe offsets are set correctly . . .

- Tim

Edited 4 time(s). Last edit at 07/25/2015 12:00PM by tadawson.

My pulleys are 20 tooth, I counted them the last time we talked about this. What line do I look at for steps/mm and microstepping?

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Knicknac
My pulleys are 20 tooth, I counted them the last time we talked about this. What line do I look at for steps/mm and microstepping?

This line in configuration.h "#define DEFAULT_AXIS_STEPS_PER_UNIT" covers the steps/mm
Regarding the microsteps it is up to the jumpers on the RAMPS see this: [www.my-home-fab.de] , not the right stepper driver but it shows the jumpers which controls the microstepping.

As for running into the bed you must measure the height between the bed and your nozzle when it is homed, and then put that value in this line "#define MANUAL_Z_HOME_POS", then there are ways to further calibrate that, this I found useful: [www.youtube.com]

Edited 1 time(s). Last edit at 07/25/2015 04:07PM by Koenig.

Ok guys, I'm done with the configuration manual. Everything seems to be working great. Now I assume I need to run a test on the autoleveling feature. Just not sure how or where that program is. Any advice now that I've come this far?

I've been trying to figure out what my next step is. I have my printer configured, I'm assuming my next step is to run an auto-level routine. I've also been looking at files to try out on Thingiverse, like a test block or something but the file formats aren't compatible. So, basically, I'm sitting here with a printer that's ready to go and pronterface can't open anything. Thiniverse files are using Python and Skeinforge, I guess I need to download them but then how would I get Pronterface to recognize a file. Am I getting ahead of myself here? What am I missing? I could download a real cad/cam system and create .stl files but I thought it would be easier to just use sketchup or blender. Confused.

Sounds like you are missing a slicer (Cura, Slic3r, etc.) to go between the .stl files and gcode that the printer can use.

- Tim

Slicr3 is integrated into Pronterface. I just downloaded Openscad and saved a basic cube with letters on every side. I was able to save the gcode as a file after slicing. I think it sliced it anyway. So I guess I just suck that into Pronterface now?