Welcome! Log In Create A New Profile


Hangprinter version 2

Posted by tobben 
Re: Hangprinter version 2
August 16, 2017 03:44PM
Hi Chris!

I avoid entanglement by keeping the lines tight and separated with my fingers when I first wind the line onto the spool. Once the line is on the spool, I keep it in place with a rubber band, tape or thin plastic film (the type you use to cover food with).

Re: Hangprinter version 2
August 17, 2017 12:02PM
Thanks Tobben,

I have developed my own method, it has seemed to work out so far. Making progress....

Edited 2 time(s). Last edit at 08/17/2017 06:25PM by brotherchris.
Re: Hangprinter version 2
August 17, 2017 06:29PM
Looking good!

Are you planning to use PTFE tube instead of fish rod rings?

Re: Hangprinter version 2
August 17, 2017 06:33PM
Yes PTFE tube, It has worked so far. One of the D lines is rubbing on the frame, don't know if the fishing eye would fix this. I am only using 10lbs test line, it might be a little light, we will see. I now have the D axis moving it up and down. Now time to do all the measuring and edit Marlin. I might have a test print out tonight.
Re: Hangprinter version 2
August 17, 2017 09:24PM
I got it working and its trying to print. It seems to be moving up and down instead of in a circle. I will compare it to my delta and see if I can figure out if I got some of the motor connections flipped over.
Re: Hangprinter version 2
August 18, 2017 03:33AM

Did you edit the bottom plate so that PTFE tubes are at the same height that fish rings would be?

You could use G6 to check motor directions.
G6 D-1 ; Should make D-motor retract 2 mm of line (and travel 1 mm towards ceiling)
G6 A-1 ; Should make A-motor retract 1 mm of line
G6 A1 ; Should make A-motor release 1 mm of line

Re: Hangprinter version 2
August 18, 2017 01:10PM
Thanks, these commands helped a lot. I have all the motors turning the right way now.

No I didn't alter it and I am quickly finding out that is an issue.

I also noticed the extruder works fine when using the button in pronterface, but doesn't seem to extrude anything while trying to print. It might be a slicer setting. It seems to just exturde then retract over and over.
Re: Hangprinter version 2
August 18, 2017 04:47PM
Ok, I have the fishing eyes on there now. I have re-measured and made the marlin adjustments from the calc. I get the printer to home dead center, then I turn it on, then I hit print. We the print start it goes crazy, the D motor starts running and take the printer up, some of the other motors move but not much. No extrusion, all the motors check out with the g6 commands, not sure what is going wrong.
Re: Hangprinter version 2
August 19, 2017 04:42AM
Before you hit print you could try:
M114 ; Prints out Hangprinters internal position (where it thinks it is)
G92 X0 Y0 Z0 E0 ; Tells Hangprinter to change its internal position to x=0, y=0, z=0, e=0
M114 ; Should print out X: 0 Y:0 Z:0 E:0

Not sure what's going on with your extruder. You could try to issue
G92 E0
G1 E10

And see if your extruder pushes 10 mm of filament down.
Then look at your gcode and see what's in there.

Re: Hangprinter version 2
August 19, 2017 11:28AM
I got the extruder going, not sure what I was doing wrong there, but I rewired the ramps and everything seems to be moving as it should now.

When I start a print it start moving the D axis down about 100mm maybe, which in turn slacks the other axis, then it starts to swing back up, but by that time the other axis are tangled because of the extra slack.

I am thinking it is either the Gcode or the ramps/mega is bad. Also when I do G6 d10 it will advance the exturder that much as well and spit out filament. So both E0 and E1 move at the same time. That also leads me to bad ramps.

Do you have a simple Gcode file that you know works on the hang that I can try for a test? That would at least help me rule out slicing.

Thanks for all the help,
Re: Hangprinter version 2
August 19, 2017 04:43PM
No probs!

It would be interesting to measure the resistance between the step pin of E1 and E0 on your ramps. I suspect they are shorted. If you can find the place they're shorted you might be able to repair it.

Sending a cube I've used for calibration

open | download - cube_shorter.gcode (244.8 KB)
Re: Hangprinter version 2
August 19, 2017 05:37PM
Already I can tell this file is working better, but the printer kinda prints in a U starts down, prints, then goes up prints, goes back down. It's almost like D is switch with another axis. Might still be bad RAMPS, I will see if I can locate another or find out whats wrong with this one. Thanks again.
Re: Hangprinter version 2
August 21, 2017 10:26AM
Just an update, I have built another printer with ABS/PLA/PETG, my first attempt was all PETG and some parts didn't work so well. I have switched to 30 lbs test fishing line and found another RAMPS board to try. My first flight should be today, I will report back.
Re: Hangprinter version 2
August 21, 2017 12:39PM
Re: Hangprinter version 2
August 21, 2017 04:15PM
This is the video of the printer printing, not sure why it is doing this. Any clues? It's doing the same thing the other ramps was doing. This is the GCODE file you sent me.

Hang test video
Re: Hangprinter version 2
August 21, 2017 05:21PM
Wow that's really weird. Maybe the error is on the Arduino Mega?

Re: Hangprinter version 2
August 21, 2017 06:09PM
I just swapped it out with another one as well thinking the same thing, still has the same issue. Do my numbers look right to you?

#define ANCHOR_A_X 0.00
#define ANCHOR_A_Y -343.70
#define ANCHOR_A_Z -146.40
#define ANCHOR_B_X 80.55
#define ANCHOR_B_Y 147.72
#define ANCHOR_B_Z -136.60
#define ANCHOR_C_X -115.42
#define ANCHOR_C_Y 175.04
#define ANCHOR_C_Z -126.80
#define ANCHOR_D_Z -29.50

My measurements from the center point are. D 87.5 CM A 403.5 cm B 221.5 cm C 264.5 cm F 631 cm S 596 cm

Edited 1 time(s). Last edit at 08/21/2017 06:11PM by brotherchris.
Re: Hangprinter version 2
August 21, 2017 08:49PM
So the big problem was cm vs mm, after I explicitly told my self to convert it before I put it in the calc....oh well, corrected.

I am happy to say the printer is printing correctly. Now the next question/issue. How to I compensate for bed level? It prints to high on one side and to low on the other. The printer is level while hanging on the celling, but I can't speak for the concrete floor I am working off of. I guess if I had to I could shim it until if worked out. It looks to be about 5mm different front to back.

Re: Hangprinter version 2
August 21, 2017 09:46PM
I made a time lapse montage of my failures, enjoy.


Hang fails
Re: Hangprinter version 2
August 22, 2017 07:38AM
Thanks! Very useful to learn how a machine with cm calibration values actually behaves. I bet others will make the same mistake.

A 5 mm difference could be from slight mis-calibration or non-flat print bed or both. I've shimmed similar amounts before. Moving your origo a few mm towards the side where nozzle gets low might also help?

I think your printer looks like it moves nicely! To get the first layer to stick, one might have to do a couple of "G6 D0.2"s during skirt or brim printing. If you can't get the PLA to stick on the blue painters tape, try plywood or MDF covered in a thin layer of white glue.

Looking forward to video/picture of the first successful print. You're so close!

Re: Hangprinter version 2
August 22, 2017 05:58PM
Many more tests today. I am very close. I think all I need is a way to consistently/repeatedly set my nozzle height and a way to level the bed a bit easier. I moved my b and c to be a bit more perpendicular and raised my bed height to be the same as AB and C just to remove some variables. I'm getting there...
Re: Hangprinter version 2
August 23, 2017 11:50AM
We did it!!! It prints!!! I set my measurement to the actual length of the fishing line which seemed to help some. I played with the start point a little to try and get it printing at the same height on the surface. I did a couple of G6 D0.2 to lower it enough then it took off. It has kind of a weird T shape going on, but I think it was caused by the print curling up and touching the print nozzle, more glue next test. Here are pics and a short video. Working now to find an easier way to find the home location for the printer. Notice the larger layers on top, this was me doing g6 b-0.2 and g6 c-0.2 trying to get some of the slack out of the line as it printed.

Thanks for all the help, this is a great project.

Successful print
Re: Hangprinter version 2
August 23, 2017 07:30PM
Congrats! Well done thumbs up

Actual XYZ lenghts of lines when printer is in origo is way to go to get the best calibration.

Thanks, no problems. Hope it will serve you well, and remember to make one for a friend winking smiley

Re: Hangprinter version 2
August 26, 2017 04:19PM
Hope you don't mind, but I made a video on my hang printer build. I am planning on having a how to video as well.


Chris's Hang printer

Edited 1 time(s). Last edit at 08/26/2017 04:37PM by brotherchris.
Re: Hangprinter version 2
August 26, 2017 06:18PM
thumbs up Very nice and informative video! Thanks for contributing to the community =)

Re: Hangprinter version 2
August 31, 2017 09:23AM

How do you slice these huge models? What software do you use? Seems like every time I try to go really large Cura won't even try to slice it and Slic3r crashes my machine. Any tips?

Re: Hangprinter version 2
August 31, 2017 07:17PM
I use Slic3r, although it crashes for me too sometimes...

The Babel tower was divided into parts that were sliced individually. Had to change two lines in the source code to make it not center the part or drop it to z=0.

Importing a clean mesh minimizes the risk of crash in my experience.

PS! I've been playing with the thought of making portable gcode before, here [forums.reprap.org]. The benefit would be extra noticable in the Hangprinter community since slicing bigger files are more difficult/tedious, and errors have more expensive consequences on bigger prints.

Re: Hangprinter version 2
September 02, 2017 05:33PM
Thanks for the info, I think the whole sharing gcode idea would be great, especially in the hang printer case. Even it you had to adjust filament settings they are very simple changes to a text file.

I got the bluetooth working today so giant prints will be on there way soon.
Re: Hangprinter version 2
September 04, 2017 03:40PM
Nice, looking forward to it!

Re: Hangprinter version 2
September 06, 2017 11:33AM
Just an update, I finally got my hang printer build video done. I go through the steps I took to get the printer up and going as fast as I can. I hope it helps others with building there printers. I am currently working on another one for calibration and setup.


Sorry, only registered users may post in this forum.

Click here to login