Folger Tech Kossel Delta 2020 Full 3D Printer Kit w/Auto-Level

Hey guys, been lurking this forum for a few months now. Great place for info on this kit. If anyone is interested I am selling my kossel kit. I no longer have time play with it so it's currently collecting dust. I am willing to let it go for a lot less than what I payed since I made some modifications. Let me know if anyone is interested. I can send pics and more info.

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Koenig

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cman8
For those that replaced your steppers, do you have to reconfigure the fw and recompile? Or is it just plug n play? I bought these as suggested. Will they work better?

[www.ebay.com]

Since they are 1.8 degree they should be just "plug'n play", you will have to change the vref on the drivers though.
And from experience I can say that you might have to change the cabling over, manufacturers seems to have no real standard to this even if they use the same connector on the motors.

Vref higher or lower?

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cman8

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Koenig

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cman8
For those that replaced your steppers, do you have to reconfigure the fw and recompile? Or is it just plug n play? I bought these as suggested. Will they work better?

[www.ebay.com]

Since they are 1.8 degree they should be just "plug'n play", you will have to change the vref on the drivers though.
And from experience I can say that you might have to change the cabling over, manufacturers seems to have no real standard to this even if they use the same connector on the motors.

Vref higher or lower?

Higher, but how high depends on the rating of the motors and the drivers.

Quote
Koenig

Quote
cman8

Quote
Koenig

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cman8
For those that replaced your steppers, do you have to reconfigure the fw and recompile? Or is it just plug n play? I bought these as suggested. Will they work better?

[www.ebay.com]

Since they are 1.8 degree they should be just "plug'n play", you will have to change the vref on the drivers though.
And from experience I can say that you might have to change the cabling over, manufacturers seems to have no real standard to this even if they use the same connector on the motors.

Vref higher or lower?

Higher, but how high depends on the rating of the motors and the drivers.

Total newb on this here so if possible can anyone lecture me. How high do i know I can go on the motors? Also how high can the stock steppers can go for the kossel?

I wasn't reviewing your part, my comment was directed towards that style of brace. Sorry you took it personal.
The fact is, that style has been around for a long time, but is usually one solid piece for each vertex. (not two mirrored, unconnected parts at each vertex)
Your comments about the design implied that it was untested - "should add some rigidity to the machine".
I was offering my direct experience with something very similar which didn't substantially improve the ridigity of the machine - at least not to the level I was hoping for.
The design was never uploaded to thingiverse or anywhere else that I know of.



If your smaller brace stiffens up the frame better than these do, then I offer you a congratulations.

Edited 2 time(s). Last edit at 09/01/2015 09:52PM by KDan.

---

-Greg

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KDan
I wasn't reviewing your part, my comment was directed towards that style of brace. Sorry you took it personal.
The fact is, that style has been around for a long time, but is usually one solid piece for each vertex. (not two mirrored, unconnected parts at each vertex)
Your comments about the design implied that it was untested - "should add some rigidity to the machine".
I was offering my direct experience with something very similar which didn't substantially improve the ridigity of the machine - at least not to the level I was hoping for.
The design was never uploaded to thingiverse or anywhere else that I know of.

[attachment 61314 EarlyBraces.jpg]

If your smaller brace stiffens up the frame better than these do, then I offer you a congratulations.

Take what personal? I said thank you for reviewing them, which is what you did by looking them over and providing your opinion. I also said thank you for sharing your comments on the other braces. I took your comments and looked at your design and then considered my own and what I could do to improve them. However; I did make them for my own use, I posted them for others to use free of charge and if you don't like them, don't use them. Although, you don't have to kibosh my design, push your own in the same post and then berate me for saying thank you in a follow up.

Edited 1 time(s). Last edit at 09/02/2015 01:09AM by thevisad.

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cman8

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Koenig

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cman8

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Koenig

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cman8
For those that replaced your steppers, do you have to reconfigure the fw and recompile? Or is it just plug n play? I bought these as suggested. Will they work better?

[www.ebay.com]

Since they are 1.8 degree they should be just "plug'n play", you will have to change the vref on the drivers though.
And from experience I can say that you might have to change the cabling over, manufacturers seems to have no real standard to this even if they use the same connector on the motors.

Vref higher or lower?

Higher, but how high depends on the rating of the motors and the drivers.

Total newb on this here so if possible can anyone lecture me. How high do i know I can go on the motors? Also how high can the stock steppers can go for the kossel?

That page you linked to doesn't say anything on how much current the motors can take, what they are rated for, so I cannot give you any help on that.
Regarding the original motors and drivers tadawson made a post earlier in this thread about a suitable vref.

This is a good page to read regarding the matter: [reprap.org]

I've now finished most of the building stage. I'm looking for more information on the next steps as my testing doesn't feel right, I've set the potentiometers to give the right Voltage as described in the manual (0.35, 0.35, 0.35, 0.55):
1- when I do prepare--> move axis-->x and move by 1mm, it seems the x-motor moves by 1mm. However, when I move the z-motor by 1mm, it moves by about 10cm. Also, which direction is +1mm, should the rail go up or down?
2- I'm not sure how the auto-home is supposed to work. What is position 0 on each axis? is it when the rail is at the top position, touching the limit switch? or is it when the extruder is at the bottom, and the distance sensor shows 0?
3- also, the inductive sensor seems to be giving 3.33V between the red and black wires no matter how close the sensor is to the board.
4- when I insert the SD Card with an STL file, I don't see the STL file in on the LCD screen. How would I print using my computer instead?
Is there a guide for troubleshooting?

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djtrance2
I've now finished most of the building stage. I'm looking for more information on the next steps as my testing doesn't feel right, I've set the potentiometers to give the right Voltage as described in the manual (0.35, 0.35, 0.35, 0.55):
1- when I do prepare--> move axis-->x and move by 1mm, it seems the x-motor moves by 1mm. However, when I move the z-motor by 1mm, it moves by about 10cm. Also, which direction is +1mm, should the rail go up or down?

Check the "#define DEFAULT_AXIS_STEPS_PER_UNIT" in configuration.h + did you properly install all the jumpers beneath the driver for the Z-axis?

+1 is up by 1mm.

+1mm is up by one mm

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djtrance2
2- I'm not sure how the auto-home is supposed to work. What is position 0 on each axis? is it when the rail is at the top position, touching the limit switch? or is it when the extruder is at the bottom, and the distance sensor shows 0?

Autohome brings all the carriages to the top touching the limitswitch, that is the homeposition for deltas, at max height.

Position 0 on all axis is when the nozzle is "touching" the bed in the centre of it.

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djtrance2
3- also, the inductive sensor seems to be giving 3.33V between the red and black wires no matter how close the sensor is to the board.

Now I don't have have an inductive sensor, but isn't there three wires?
One for +
One for - (ground)
And one for the signal.
Meaning that between two wires you will always have same readings

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djtrance2
4- when I insert the SD Card with an STL file, I don't see the STL file in on the LCD screen. How would I print using my computer instead?

I suppose you already have installed the arduino IDE, to be able to flash the firmware, so you should have the necessary drivers.
So you would only need pronterface to be able to print from the computer.

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djtrance2
Is there a guide for troubleshooting?

There is tons of information in this thread alone, if not found here you could always use the search function of the forum + there is this [reprap.org]

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Koenig

Now I don't have have an inductive sensor, but isn't there three wires?
One for +
One for - (ground)
And one for the signal.
Meaning that between two wires you will always have same readings

Inductive sensors have three wires like you indicate, Blue, Black and Brown. You can wire them in either NO or NC with the proper sensors. The color scheme is not the normal scheme, blue is negative, brown is + with black being the sense wire. They usually do not operate on 3.3v, but work from 5v - 17v roughly.

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Koenig

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cman8

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Koenig

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cman8

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Koenig

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cman8
For those that replaced your steppers, do you have to reconfigure the fw and recompile? Or is it just plug n play? I bought these as suggested. Will they work better?

[www.ebay.com]

Since they are 1.8 degree they should be just "plug'n play", you will have to change the vref on the drivers though.
And from experience I can say that you might have to change the cabling over, manufacturers seems to have no real standard to this even if they use the same connector on the motors.

Vref higher or lower?

Higher, but how high depends on the rating of the motors and the drivers.

Total newb on this here so if possible can anyone lecture me. How high do i know I can go on the motors? Also how high can the stock steppers can go for the kossel?

That page you linked to doesn't say anything on how much current the motors can take, what they are rated for, so I cannot give you any help on that.
Regarding the original motors and drivers tadawson made a post earlier in this thread about a suitable vref.

This is a good page to read regarding the matter: [reprap.org]

Thanks for that. This will help for sure.

I am looking for help.

After a month, three Arduino boards and two RAMPS, I still cannot get the printer to fire any of the motors. I made this troubleshooting sheet to try and track down issues. It just HAS to be something simple at this point, I know the hardware is good, but it just won't do anything.

The only thing not filled out on that sheet is the heat bed and hotend voltages, I currently have them unhooked but they were working just fine a few days ago.


When sending either G28 or G29, nothing happens. It will say "SENDING:G##" then hang indefinitely until you do something else.

The GUI controls in Pronterface don't do anything when pressed. Nothing in the console, nothing on the GUI.

Any suggestion is appreciated. I'm freaking out at this point.

Whats your setting n pronterface? is the Baud rate set high enough? Do you have the right com port? Also can you read the board on audrino when loading the FW files?

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cman8
Whats your setting n pronterface? is the Baud rate set high enough? Do you have the right com port? Also can you read the board on audrino when loading the FW files?

Baudrate is set to 250000 and the same COM port as Device Manager (Win 7 64bit). I'm not sure what you mean by "read the board on Arduino when loading"

If you mean what I think, then yes, you can select the 'Tools>Port>COM#' (COM:19 in my case)

Im assuming you could upload the marlin Config files to the board

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cman8
Im assuming you could upload the marlin Config files to the board

Yes, the FW was able to be uploaded without error. I tested with Blink first to confirm, then uploaded the Marlindelta_2 FW.

When I go to print an STL file that i sliced with Sli3er, heats the hotend up like it should, but then just sits there. It's almost like none of the motors are getting any voltages. I have the stepper motors plugged in the way the manual indicated, I was afraid to flip the plugs in fear of hurting them.

Did you put the stepper motor drivers in the correct orientation? Have you measured the adjustable current sense voltage on them?

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nebbian
Did you put the stepper motor drivers in the correct orientation? Have you measured the adjustable current sense voltage on them?

If the correct orientation is with the potentiometer facing towards the AUX4 pins, that is, away from the power block, then yes.

As per the screenshot of the spreadsheet I posted, I have dialed in 0.35v for the X, Y, and Z stepper drivers, and 0.60v for the Extruder stepper driver. Is that what you mean by the "adjustable current sense voltage"?

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fattmann

If the correct orientation is with the potentiometer facing towards the AUX4 pins, that is, away from the power block, then yes.

As per the screenshot of the spreadsheet I posted, I have dialed in 0.35v for the X, Y, and Z stepper drivers, and 0.60v for the Extruder stepper driver. Is that what you mean by the "adjustable current sense voltage"?

Ah fair enough. Yep that's what I mean.

It's a strange problem that you've got. The normal culprit is a mismatched baud rate, but it seems as if you have communication with your arduino board becuase the heater is heating up and you can see the end stops trigger. So what's left is power to your motors.

Things I'd check:
1) Do you have power to BOTH sets of 12V leads on the RAMPS board? From memory there is one set for heaters, and one set for motors.
2) Can your carriages move up and down by hand, which is turning the motors?
3) Have you selected "Delta" in the marlin firmware?
4) Have you put jumpers on the x-min and y-min end stop pins so that in normal operation, every signal pin is connected to ground?
5) Do your motors buzz or make any sound when you try to drive them?
6) How are you trying to drive your motors? Have you pressed the "Home" button in pronterface after connecting?
7) When you connect pronterface to your delta, does it come up with some text in the console?


I'm not sure what your problem is but this might help to narrow it down.

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fattmann

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nebbian
Did you put the stepper motor drivers in the correct orientation? Have you measured the adjustable current sense voltage on them?

If the correct orientation is with the potentiometer facing towards the AUX4 pins, that is, away from the power block, then yes.

As per the screenshot of the spreadsheet I posted, I have dialed in 0.35v for the X, Y, and Z stepper drivers, and 0.60v for the Extruder stepper driver. Is that what you mean by the "adjustable current sense voltage"?

That is the correct voltage, what you are describing indicates that voltage is not getting to the motors. This could be an issue with the stepper drivers, the arduino, the RAMPS, the wiring or the power supply. The picture below shows the position of the stepper driver for an 4988, an 8825 is reversed and the adjustable pot is in the opposite direction, pay attention to where the reset button is. I am going to assume that it is not your RAMPS or Mega since you have multiple of those. The second picture shows you the orientation of the wiring and the color code it should follow, check that your wiring is properly connected and in the correct order.

In the last picture, with the power on the printer use a voltmeter to test the spots. Yellow is your ground connection, red is your 3.3-5v connection and the green is your 12v power. You should have these voltages at these locations while the printer is on. Also check to make sure that your jumpers are on and in the right place for the stepper motors to be in 16 step mode. There is a set of 3 of these under each stepper motor driver.








Edited 4 time(s). Last edit at 09/02/2015 10:19PM by thevisad.

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nebbian

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fattmann

If the correct orientation is with the potentiometer facing towards the AUX4 pins, that is, away from the power block, then yes.

As per the screenshot of the spreadsheet I posted, I have dialed in 0.35v for the X, Y, and Z stepper drivers, and 0.60v for the Extruder stepper driver. Is that what you mean by the "adjustable current sense voltage"?

Ah fair enough. Yep that's what I mean.

It's a strange problem that you've got. The normal culprit is a mismatched baud rate, but it seems as if you have communication with your arduino board becuase the heater is heating up and you can see the end stops trigger. So what's left is power to your motors.

Things I'd check:
1) Do you have power to BOTH sets of 12V leads on the RAMPS board? From memory there is one set for heaters, and one set for motors.
2) Can your carriages move up and down by hand, which is turning the motors?
3) Have you selected "Delta" in the marlin firmware?
4) Have you put jumpers on the x-min and y-min end stop pins so that in normal operation, every signal pin is connected to ground?
5) Do your motors buzz or make any sound when you try to drive them?
6) How are you trying to drive your motors? Have you pressed the "Home" button in pronterface after connecting?
7) When you connect pronterface to your delta, does it come up with some text in the console?


I'm not sure what your problem is but this might help to narrow it down.

1) Yes, voltage reads the same on both leads.

2) I can move the carriages up and down by hand, with the belt turning the axle on the motor. The set screw on the pulleys are also set, so the actual axle is rotating, not just the pulley free spinning on the axle

3) I am unsure what you mean. The Folger Tech manual made no indication of a setting that needed to be changed specifically for the FW I grabbed from their Google Drive. Is that a setting in the Arduino software, or a line in the FW code itself?

4) I have seen the the use of "Zmin" but not "Xmin or Ymin." I was under the impression that there is only the endstops at the top of the rails? Sorry I'm not sure on that question.

5) Motors do not buzz, vibrate, produce heat, or anything. I unplugged the hotend fan just to make sure I wasn't missing any vibrations. The only noise/vibration/heat is coming from the PSU that is off to the side.

6) I have tried the G28 command, where it just says "SENDING:G28" then never does anything. I have also tried the Home button on the GUI in Pronterface- that does nothing at all, doesn't populate anything in the console, or cause any movement on the printer.

7) Yes. It has several lines, ending with confirmation that the SD card is ok. No errors or anything abnormal. I am then able to use Pronterface to adjust the temp of both the hotend and the bed, and load a file to be printed. Anything that would cause a stepper motor or extruder to activate does nothing at all, or just hangs when sending the command.

Thanks again for the help! I am going to have to retire to bed shortly, so If I don't catch any response I will follow up tomorrow.

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thevisad

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fattmann

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nebbian
Did you put the stepper motor drivers in the correct orientation? Have you measured the adjustable current sense voltage on them?

If the correct orientation is with the potentiometer facing towards the AUX4 pins, that is, away from the power block, then yes.

As per the screenshot of the spreadsheet I posted, I have dialed in 0.35v for the X, Y, and Z stepper drivers, and 0.60v for the Extruder stepper driver. Is that what you mean by the "adjustable current sense voltage"?

That is the correct voltage, what you are describing indicates that voltage is not getting to the motors. This could be an issue with the stepper drivers, the arduino, the RAMPS, the wiring or the power supply. The picture below shows the position of the stepper driver for an 4988, an 8825 is reversed and the adjustable pot is in the opposite direction, pay attention to where the reset button is. I am going to assume that it is not your RAMPS or Mega since you have multiple of those. The second picture shows you the orientation of the wiring and the color code it should follow, check that your wiring is properly connected and in the correct order.

In the last picture, with the power on the printer use a voltmeter to test the spots. Yellow is your ground connection, red is your 3.3-5v connection and the green is your 12v power. You should have these voltages at these locations while the printer is on. Also check to make sure that your jumpers are on and in the right place for the stepper motors to be in 16 step mode. There is a set of 3 of these under each stepper motor driver.

I certainly agree with the hypothesis that the motors are not getting voltages. I tested the leads going to the extruder motor, while having a helper press to extrude 5mm of filament- no voltage, no movement.

My stepper drivers are oriented as you have shown. My voltages at the Yellow/Red is 4.76v, and at the Green/Red is 12.29v. All of the jumpers are in the correct place matching the build manual, and the picture you provided. This includes the jumper near the reset button.

I should also add that trying to manually control it with the LCD screen and knob will show echo lines on the console, but still doesn't activate anything.

Thanks again.

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fattmann
I am looking for help.

After a month, three Arduino boards and two RAMPS, I still cannot get the printer to fire any of the motors. I made this troubleshooting sheet to try and track down issues. It just HAS to be something simple at this point, I know the hardware is good, but it just won't do anything.

The only thing not filled out on that sheet is the heat bed and hotend voltages, I currently have them unhooked but they were working just fine a few days ago.


When sending either G28 or G29, nothing happens. It will say "SENDING:G##" then hang indefinitely until you do something else.

The GUI controls in Pronterface don't do anything when pressed. Nothing in the console, nothing on the GUI.

Any suggestion is appreciated. I'm freaking out at this point.

Don't know if you have ever tried the RAMPS test code, but it would get you down to the bare bones to verify your boards, wiring, and hardware.
RAMPS wiki and test code
The test code loads directly onto the Arduino so you bypass Marlin and Pronterface, etc. When I used it, I didn't have the belts on the steppers.
Also, see this Youtube RAMPS test.

Rick

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fattmann

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thevisad

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fattmann

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nebbian
Did you put the stepper motor drivers in the correct orientation? Have you measured the adjustable current sense voltage on them?

If the correct orientation is with the potentiometer facing towards the AUX4 pins, that is, away from the power block, then yes.

As per the screenshot of the spreadsheet I posted, I have dialed in 0.35v for the X, Y, and Z stepper drivers, and 0.60v for the Extruder stepper driver. Is that what you mean by the "adjustable current sense voltage"?

That is the correct voltage, what you are describing indicates that voltage is not getting to the motors. This could be an issue with the stepper drivers, the arduino, the RAMPS, the wiring or the power supply. The picture below shows the position of the stepper driver for an 4988, an 8825 is reversed and the adjustable pot is in the opposite direction, pay attention to where the reset button is. I am going to assume that it is not your RAMPS or Mega since you have multiple of those. The second picture shows you the orientation of the wiring and the color code it should follow, check that your wiring is properly connected and in the correct order.

In the last picture, with the power on the printer use a voltmeter to test the spots. Yellow is your ground connection, red is your 3.3-5v connection and the green is your 12v power. You should have these voltages at these locations while the printer is on. Also check to make sure that your jumpers are on and in the right place for the stepper motors to be in 16 step mode. There is a set of 3 of these under each stepper motor driver.

I certainly agree with the hypothesis that the motors are not getting voltages. I tested the leads going to the extruder motor, while having a helper press to extrude 5mm of filament- no voltage, no movement.

My stepper drivers are oriented as you have shown. My voltages at the Yellow/Red is 4.76v, and at the Green/Red is 12.29v. All of the jumpers are in the correct place matching the build manual, and the picture you provided. This includes the jumper near the reset button.

I should also add that trying to manually control it with the LCD screen and knob will show echo lines on the console, but still doesn't activate anything.

Thanks again.

Try to perform this test to verify that the windings are ok on your motors. Besides the crappy fuses/low voltage caps on them, the ramps 1.4 is a pretty solid little board and if both of them are doing it, I suspect other issues.

https://www.youtube.com/watch?v=1U9pf7S_ov4

Edited 1 time(s). Last edit at 09/02/2015 11:19PM by thevisad.

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fattmann

4) I have seen the the use of "Zmin" but not "Xmin or Ymin." I was under the impression that there is only the endstops at the top of the rails? Sorry I'm not sure on that question.

Some build manuals say to put jumpers on the pins that are used for x min and y min endstops. You won't actually have endstops there, just jumpers on the RAMPS board. I'm not sure if it will help.

Any chance of a picture of your RAMPS board with wiring?

Edited 1 time(s). Last edit at 09/02/2015 11:19PM by nebbian.

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fattmann

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thevisad

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fattmann

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nebbian
Did you put the stepper motor drivers in the correct orientation? Have you measured the adjustable current sense voltage on them?

If the correct orientation is with the potentiometer facing towards the AUX4 pins, that is, away from the power block, then yes.

As per the screenshot of the spreadsheet I posted, I have dialed in 0.35v for the X, Y, and Z stepper drivers, and 0.60v for the Extruder stepper driver. Is that what you mean by the "adjustable current sense voltage"?

That is the correct voltage, what you are describing indicates that voltage is not getting to the motors. This could be an issue with the stepper drivers, the arduino, the RAMPS, the wiring or the power supply. The picture below shows the position of the stepper driver for an 4988, an 8825 is reversed and the adjustable pot is in the opposite direction, pay attention to where the reset button is. I am going to assume that it is not your RAMPS or Mega since you have multiple of those. The second picture shows you the orientation of the wiring and the color code it should follow, check that your wiring is properly connected and in the correct order.

In the last picture, with the power on the printer use a voltmeter to test the spots. Yellow is your ground connection, red is your 3.3-5v connection and the green is your 12v power. You should have these voltages at these locations while the printer is on. Also check to make sure that your jumpers are on and in the right place for the stepper motors to be in 16 step mode. There is a set of 3 of these under each stepper motor driver.

I certainly agree with the hypothesis that the motors are not getting voltages. I tested the leads going to the extruder motor, while having a helper press to extrude 5mm of filament- no voltage, no movement.

My stepper drivers are oriented as you have shown. My voltages at the Yellow/Red is 4.76v, and at the Green/Red is 12.29v. All of the jumpers are in the correct place matching the build manual, and the picture you provided. This includes the jumper near the reset button.

I should also add that trying to manually control it with the LCD screen and knob will show echo lines on the console, but still doesn't activate anything.

Thanks again.

Could yo perhaps post a photo of your ramps with everything connected?

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Koenig


Could yo perhaps post a photo of your ramps with everything connected?

Not the best picture, took them real quick on the way out of the house to work this morning.

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fattmann

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Koenig


Could yo perhaps post a photo of your ramps with everything connected?

Not the best picture, took them real quick on the way out of the house to work this morning.

wNlZa4c.jpg

uDyAbOG.jpg

Yeah, a bit hard to see, but from what I can see you have not connected power to all four connections on the green block in the lower right corner of the picture.

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Koenig

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fattmann

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Koenig


Could yo perhaps post a photo of your ramps with everything connected?

Not the best picture, took them real quick on the way out of the house to work this morning.
]

Yeah, a bit hard to see, but from what I can see you have not connected power to all four connections on the green block in the lower right corner of the picture.

I guess it does look like that, sorry I'll get better pictures tonight. Both 12v lines are in the green terminal. I took the voltage readings off the screws in the terminals.

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fattmann

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Koenig

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fattmann

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Koenig


Could yo perhaps post a photo of your ramps with everything connected?

Not the best picture, took them real quick on the way out of the house to work this morning.
]

Yeah, a bit hard to see, but from what I can see you have not connected power to all four connections on the green block in the lower right corner of the picture.

I guess it does look like that, sorry I'll get better pictures tonight. Both 12v lines are in the green terminal. I took the voltage readings off the screws in the terminals.

If I were you the first thing that I would do is disconnect the LCD. For what its worth, I had all sorts of problems with mine connected. Dunno if you tried this I didn't follow the entire thread.

Worth a shot at this point.

Mike