Hangprinter version 3
Posted by tobben
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Re: Hangprinter version 3 June 22, 2019 09:10PM |
back again with bag full of questions 
as i said, i aim to order most of my parts from aliexpress, mostly from makerbase and trianble labs. Still as Tob's BOM asks for either too a general item or explicitly different item, Id like to confirm a few things before actually placing the order. Here comes...
1) Ramps + arduino mega 1.4/1.6 vs mks gen L
I know BOM asks for RAMPS plus arduino mega. wouldnt Makerspace's mks gen L (aliexpress) do just as well if not better though? I hear there's less hassle with it (plus i may use other hardware from them) but haven't heared of anyone from hangprinter community praising/using it.
if it may not be such a good option after all than should i get ramps 1.4 or 1.6?
2) mechanduino (clones)
makerbase, as you surely know, manufactures mechanduino clones that come hooked to nema17 42 steps stepper already (aliexpress). now, as it is a clone, it should behave the same way (although they told me some pins are weired differently). anyways, does anyone has any experience with them? would you recommend using them or would you not? (id appreciate (expert) guesses too
3) extruder+hotend
im looking at this triangle lab e3d volcano ripp (aliexpress) . i would like to get the whole "set 5" (need to scroll down to see the desription of various sets) which includes extreuder, hotend, motor, and fan. I read its a "good fake" as much of an oxymoron as it sounds. any voices against it?
Id be super happy if someone could get back to me with any opinion or experience. i should be fine with other bits of the puzzle for now, but really can't make up my mind on mentioned topics.
Best,
Mizu
as i said, i aim to order most of my parts from aliexpress, mostly from makerbase and trianble labs. Still as Tob's BOM asks for either too a general item or explicitly different item, Id like to confirm a few things before actually placing the order. Here comes...
1) Ramps + arduino mega 1.4/1.6 vs mks gen L
I know BOM asks for RAMPS plus arduino mega. wouldnt Makerspace's mks gen L (aliexpress) do just as well if not better though? I hear there's less hassle with it (plus i may use other hardware from them) but haven't heared of anyone from hangprinter community praising/using it.
if it may not be such a good option after all than should i get ramps 1.4 or 1.6?
2) mechanduino (clones)
makerbase, as you surely know, manufactures mechanduino clones that come hooked to nema17 42 steps stepper already (aliexpress). now, as it is a clone, it should behave the same way (although they told me some pins are weired differently). anyways, does anyone has any experience with them? would you recommend using them or would you not? (id appreciate (expert) guesses too
3) extruder+hotend
im looking at this triangle lab e3d volcano ripp (aliexpress) . i would like to get the whole "set 5" (need to scroll down to see the desription of various sets) which includes extreuder, hotend, motor, and fan. I read its a "good fake" as much of an oxymoron as it sounds. any voices against it?
Id be super happy if someone could get back to me with any opinion or experience. i should be fine with other bits of the puzzle for now, but really can't make up my mind on mentioned topics.
Best,
Mizu
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Re: Hangprinter version 3 July 25, 2019 05:38AM |
Hey
Do you have had similar issues with print quality than I had with the last project (still going on)?
The skin was partly separated from the printed object and that caused issues during post-processing (sanding, etc.) It affected only the outermost wall, the inner walls were connected as they should have been.
Here's a picture of the crime scene. Any suggestions are warmly welcome, since I'm about to start the next project soon.
Do you have had similar issues with print quality than I had with the last project (still going on)?
The skin was partly separated from the printed object and that caused issues during post-processing (sanding, etc.) It affected only the outermost wall, the inner walls were connected as they should have been.
Here's a picture of the crime scene. Any suggestions are warmly welcome, since I'm about to start the next project soon.
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Re: Hangprinter version 3 October 12, 2019 04:47AM |
I'm currently designing a bracket for the HP4 bldc servo motor and the spool, and I wanted to share my tests so far.
The bracket is meant for the ODrive D5065 motor. My goal is to design a single motion unit, that includes the motor, a belt tensioner and the spool system in one rigid frame, which I probably am going to lasercut out of sheet metal. For now, I'm still thinking about the spool system. If you look few posts back in this thread, there was a discussion about the constant radius of the spool and how to compensate the line build up. An idea I had, was to route the line in a small groove in the middle of the GT2 spool, in the way that the belt is pressing it against the spool as you can see in the last pic.
I just tried to block the spool from rotating and pulled the line as hard as I could and it didn't move at all
It's still too early to say this concept works, but it is a promising start. It might be, that constant line movement is going to bite into the belt and it fails that way. You'll never know. What I'll do next is rerouting the end of the line onto a second spool, which I most likely will attach onto the same spool axle. And that spool will rotate independently from the first one. I was also thinking to spring load it, so that the excess line is always spooled up as the line moves.
The bracket is meant for the ODrive D5065 motor. My goal is to design a single motion unit, that includes the motor, a belt tensioner and the spool system in one rigid frame, which I probably am going to lasercut out of sheet metal. For now, I'm still thinking about the spool system. If you look few posts back in this thread, there was a discussion about the constant radius of the spool and how to compensate the line build up. An idea I had, was to route the line in a small groove in the middle of the GT2 spool, in the way that the belt is pressing it against the spool as you can see in the last pic.
I just tried to block the spool from rotating and pulled the line as hard as I could and it didn't move at all
It's still too early to say this concept works, but it is a promising start. It might be, that constant line movement is going to bite into the belt and it fails that way. You'll never know. What I'll do next is rerouting the end of the line onto a second spool, which I most likely will attach onto the same spool axle. And that spool will rotate independently from the first one. I was also thinking to spring load it, so that the excess line is always spooled up as the line moves.
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Re: Hangprinter version 3 October 12, 2019 06:25AM |
Cool!
Independent spool units are nice.
If you can place them at the anchors (instead of having all several spools at one anchor), you will get less line flex, since there will be less suspended line in the air.
Good idea to pinch the line under the belt.
That might actually work very well =D
You could pinch it for several rounds (along a helix groove), or just increase the spool radius, if one round of pinched line isn't enough.
It might be a challenge assure zero slippage over time, since both line and belt will change properties as they get old/worn down.
Some data on that would be super interesting, like accelerating a 5kg weight quickly up and down 1 m 10000 times or something.
Using high accelerations would be interesting because the belt will flex/contract a bit when tension changes, and I don't know how it will affect the line.
Hopefully very little.
Anyways, that might be a very nice upgrade of the spool system
blog
Independent spool units are nice.
If you can place them at the anchors (instead of having all several spools at one anchor), you will get less line flex, since there will be less suspended line in the air.
Good idea to pinch the line under the belt.
That might actually work very well =D
You could pinch it for several rounds (along a helix groove), or just increase the spool radius, if one round of pinched line isn't enough.
It might be a challenge assure zero slippage over time, since both line and belt will change properties as they get old/worn down.
Some data on that would be super interesting, like accelerating a 5kg weight quickly up and down 1 m 10000 times or something.
Using high accelerations would be interesting because the belt will flex/contract a bit when tension changes, and I don't know how it will affect the line.
Hopefully very little.
Anyways, that might be a very nice upgrade of the spool system
blog
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Re: Hangprinter version 3 October 12, 2019 07:00AM |
Thanks!
I just put a heavy weight on the line and looked first if the line holds, and after I couldn't see any slipping, I bounced the whole system until the line snapped Video: testing slipping
No slipping what so ever
I believe the line should be able to handle 40 kg of drag, so friction-wise I can't see any issues. Obviously the long term failure rate is a question mark, but I think it might work quite well because the line isn't cutting radially into the belt. The only force is applied axially and the belt is pressed by the line by only 0,25 mm
Your idea of hooking some weight on the line and do some repetitive acceleration testing sounds very good! I'll try to set up the electronics next week. What values would you suggest for weight, speed and acceleration?
Here are also some close ups of the GT2 spool and the belt directly after the test. For the spool I used Octofiber PETG-CF.
I just put a heavy weight on the line and looked first if the line holds, and after I couldn't see any slipping, I bounced the whole system until the line snapped Video: testing slipping
No slipping what so ever
I believe the line should be able to handle 40 kg of drag, so friction-wise I can't see any issues. Obviously the long term failure rate is a question mark, but I think it might work quite well because the line isn't cutting radially into the belt. The only force is applied axially and the belt is pressed by the line by only 0,25 mm
Your idea of hooking some weight on the line and do some repetitive acceleration testing sounds very good! I'll try to set up the electronics next week. What values would you suggest for weight, speed and acceleration?
Here are also some close ups of the GT2 spool and the belt directly after the test. For the spool I used Octofiber PETG-CF.
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Re: Hangprinter version 3 October 12, 2019 11:14AM |
Woah, that's even more friction than I imagined. Impressive!
CF enforced plastics have a quite rough surface.
Where did the line snap?
Was it the CF that wore down the line?
Since I would be aiming for HP usage, I'd test numbers relevant to the application first.
I'd use ca 50% more weight, speed and acceleration than my HP4 prototype is experiencing.
So ca 5 kg of weight, accelerate 15 m/s² , up to 1 m/s. Use a distance of 1 m up and down, say 10k times.
That's a 3h test. You could go crazy and just let it run all night if you're feeling confident
It would also be interesting to know if the mechanism works with pure PLA.
A spool out of PLA printed hot (say 240 C) would give much less friction than the PLA-CF in your prototype, I guess.
It would be interesting to know if it would still be enough, or if the CF is required.
Images like the one you showed would be a very interesting part of the result.
In particular, if the line does slip, I'm interested in how damaged the belt gets.
Also interesting to know if a slipping line cuts into the spool.
The mechanism is interesting in it's own right, so if the HP4 application proves to be well within limits of the mechanism, I would have done additional tests.
Like, measuring a slowly applied force up until the line breaks or starts slipping, or until the plastic spool breaks.
(Film a weight that is hooked onto a one end of a line, and pulled. Could capture both force and amount of slip/flex in one shot.)
Abruptly applied force is also interesting (requires a high-speed camera, or a weight that can store a max value).
blog
CF enforced plastics have a quite rough surface.
Where did the line snap?
Was it the CF that wore down the line?
Since I would be aiming for HP usage, I'd test numbers relevant to the application first.
I'd use ca 50% more weight, speed and acceleration than my HP4 prototype is experiencing.
So ca 5 kg of weight, accelerate 15 m/s² , up to 1 m/s. Use a distance of 1 m up and down, say 10k times.
That's a 3h test. You could go crazy and just let it run all night if you're feeling confident
It would also be interesting to know if the mechanism works with pure PLA.
A spool out of PLA printed hot (say 240 C) would give much less friction than the PLA-CF in your prototype, I guess.
It would be interesting to know if it would still be enough, or if the CF is required.
Images like the one you showed would be a very interesting part of the result.
In particular, if the line does slip, I'm interested in how damaged the belt gets.
Also interesting to know if a slipping line cuts into the spool.
The mechanism is interesting in it's own right, so if the HP4 application proves to be well within limits of the mechanism, I would have done additional tests.
Like, measuring a slowly applied force up until the line breaks or starts slipping, or until the plastic spool breaks.
(Film a weight that is hooked onto a one end of a line, and pulled. Could capture both force and amount of slip/flex in one shot.)
Abruptly applied force is also interesting (requires a high-speed camera, or a weight that can store a max value).
blog
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Re: Hangprinter version 3 October 13, 2019 05:28AM |
Yes, the firmware should be straight forward to install. Just use the Duet2CombinedFirmware.bin you find in the repo (https://gitlab.com/tobben/hangprinter/tree/version_4_dev/firmware/RepRapFirmware), and follow standard Duet installation procedure. Gcode should to the magic, yes Be aware that your ODrive configuration will affect the movements. Max acceleration, max speed, step size etc needs to be configured correctly in the ODrive firmware. There's an example that matches my specific motors here: [gitlab.com] Follow the official ODrive documentation to find numbers that match your motors.
If the fishing line has any flex at all, this will affect the readings. So if the line (and hence the pattern) is stretched out, you might wind in 10.1 mm when you thought you did only 10.0.
On the other hand, since you're detecting the pattern, you'll know when you have unwound the same segment of fishing line, regardless of how stretched it was when wound and unwound.
This makes the system immune to a family of errors where flex is "stored" on the spool when wound in under heavy load.
The line will always be twisted though. How would the system cope with that?
And how would it behave if the line got very slack? Could we route the line through a very thin transparent tube, to keep it from kinking under the sensor?
For such a sensor to be useful, it would need to be very fool proof since so many weird things can happen during a print.
blog
Be aware that your ODrive configuration will affect the movements. Max acceleration, max speed, step size etc needs to be configured correctly in the ODrive firmware. There's an example that matches my specific motors here: [gitlab.com] Follow the official ODrive documentation to find numbers that match your motors.If the fishing line has any flex at all, this will affect the readings. So if the line (and hence the pattern) is stretched out, you might wind in 10.1 mm when you thought you did only 10.0.
On the other hand, since you're detecting the pattern, you'll know when you have unwound the same segment of fishing line, regardless of how stretched it was when wound and unwound.
This makes the system immune to a family of errors where flex is "stored" on the spool when wound in under heavy load.
The line will always be twisted though. How would the system cope with that?
And how would it behave if the line got very slack? Could we route the line through a very thin transparent tube, to keep it from kinking under the sensor?
For such a sensor to be useful, it would need to be very fool proof since so many weird things can happen during a print.
blog
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Re: Hangprinter version 3 October 13, 2019 05:35AM |
Let me do a dedicated thread to this topic, and we continue the discussion there
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Re: Hangprinter version 3 November 20, 2019 08:21PM |
Hi,
i am trying to build a HangPrinter too and i had a lot of hours spent searching and watching images, videos and build documentation for hardware, firmware, software. The hardest thing for me was to figure out how lines are installed properly. I did not built my hangprinter in real for now but planning to do it (sourcing hardware and so on). I drew some sketch for lines and wanted you to ask if understood it correctly.
As far as i know there are 9 lines in total
* A1 + A2 => 2 lines on one spool
* B1 + B2 => 2 lines on one spool
* C1 + C2 => 2 lines on one spool
* D1, D2, D3 => 3 lines on one spool
to better follow i just marked the full A2 path for example. You can see that A2 joins A1 again at the effector (triangle).
I saw in Chris Basement videos that the A1+A2, B1+B2 and C1+C2 have a common knot on the effector slider each, while D1,D2,D3 have there own slider for each. So in total there are 6 sliders (by the way i thought using guitar tuner mechanics for this use case)
I'm happy to retrieve your feedback.
cheers, Mario :-)
i am trying to build a HangPrinter too and i had a lot of hours spent searching and watching images, videos and build documentation for hardware, firmware, software. The hardest thing for me was to figure out how lines are installed properly. I did not built my hangprinter in real for now but planning to do it (sourcing hardware and so on). I drew some sketch for lines and wanted you to ask if understood it correctly.
As far as i know there are 9 lines in total
* A1 + A2 => 2 lines on one spool
* B1 + B2 => 2 lines on one spool
* C1 + C2 => 2 lines on one spool
* D1, D2, D3 => 3 lines on one spool
to better follow i just marked the full A2 path for example. You can see that A2 joins A1 again at the effector (triangle).
I saw in Chris Basement videos that the A1+A2, B1+B2 and C1+C2 have a common knot on the effector slider each, while D1,D2,D3 have there own slider for each. So in total there are 6 sliders (by the way i thought using guitar tuner mechanics for this use case)
I'm happy to retrieve your feedback.
cheers, Mario :-)
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Re: Hangprinter version 3 November 21, 2019 07:26AM |
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