Trying to find solutions to use filament to the max...

[HaryPlotter 1]

Hey there,

 

have only a few posts, but my previous account got deleted by an update to a new community server a few years ago. Since then I had alot othe stuff to do. Now I´´´  m back...

 

Back with an important issue (so to me). As I am already using my UM3 ext. for a while and made some changes to it here and there I want yet to add another change to it.

 

With some help we might help others too, to help save filament/ prints and therefore the environment, nature, the word and not least the universe ;O)

 

So now to my question:

 

How often does it happen (more to newbies probably), that you print and then there comes the time that your role slowly expires. Now you have a couple of options:

 

1. Or you know the weight of the empty spool and you weigh the "rest" of you filament and the you know how mucht you can still print (But that is time consuming and nobody really does that every time).

2. Or you go by eye and pray...

3. Or you just "pause" your print at a certain usage of your filament and change it rapidly by hand while your printer is on pause.

 

The last option I found out is the best for me to keep on even with big prints. With this trick you could overcome unfinished prints, therefore cloaked nozzles (at least for the PVA-filament), you save time, money and so on.

 

Now you are not always in to check for the current usage of your filament so I thought this should be feesible with someone who knows a bit about programming with python and combining this with a sensor. In this case that would be a normal photocell that detects light and thus gives out a command to something like an arduino to change the state of the UM3 from "printing" to "Pause" (http://192.XXX.XXX.XXX/api/v1/print_job/state). Once the filament is changed we could then manually or by direct input rechange the state to "printing".

 

Maybe I can find some fellows who can realize this kind of painsaving "addon".

 

I already thought about where to put the fotocell. I should be possible to print a box to install it right underneath the feeders (2 fotocells for each feeder).  So if the filament ever is used up it will pass by the feeder and thus activating the fotocell. The fotocell should give out a signal to a simple pc (maybe arduino) that is then sending a command to the UM3 to pause.

 

That should help: https://micro-dev.de/showthread.php?tid=42  (It´``` s in german but basically i´t s the setup I would like to create...

 

Now I know about some basic comands but this task need a group of people who are more into programming and stuff. But first I would like to know if this idea catches your interest in basic. Then we could at least figure out a way together in getting some more fun into printing.

 

What do you think about it?

 

Greetings

 

 

 

Daniel

[geert_2 557]

The problem is that systems with sensors and wires on rotating stuff are prone to all sorts of errors: false positives, and not correctly detecting real amounts, due to the spool rotating and the "sensor window" being covered by that rotating spool. These things will complicate the situation.

 

But recently there was a post of a guy who printed labels with a measuring scale showing the remaining amount. Then he glued the labels to his spools. The idea was similar to the scales on glass bottles and measuring jars in the kitchen. This actually is a nice and simple solution, I think. It should have been standard on all spools, since it can easily be injection moulded into the spool. But I don't remember that guy's name. Maybe you can find that thread for ideas?

 

[HaryPlotter 1]

Hi Geert_2,

 

thank you for your input but maybe my previous post was not too understandible. I will try to be more exact:

 

1. I´  m not trying to build something complicated like a flow-sensor or something in this direction. (although I know as of today that someone can introduce an S5 flow-sensor to an U3, but that needs to trigger some sofware-update and I´m far away of reprogramming the software api).

 

2. There is one simple measuring device --> the laser!

 

A) The laser connects to the reflector on the other side --> Printer stops for pausing...

B) No passthrough --> no connection --> printer is not disturbed

 

3. The laser is (will be) connected to or an arduino  or better a rasberry because of the preinstalled LAN-connection and programmed so if the laser connects the machine is said to stop.

 

4. Today I have been to the "formnext" in Frankfurt and I talked to a software-engeneer of ultimaker. He told me the prgram of the ultimaker can be paused and the comand for it can be found directly in the api of the printer. Nonetheless I left my card there so maybe he will help me out with the exact command. If not I will try my luck in the couple of the next days.

 

5. Anyhow the printing of the filament-trap is pretty easy and I´ m sure I will have a box ready by the end of next week.

 

6. The probelm is, that I don´ t know anything about programming but there might be someone out there that already did program with e.g. pyhton or anything that can be uploaded to a rasberry and started witht the laser diode hooked on it as a trigger-switch.

 

So in this case I would need some support in programming as I would contribute the holding device for the laser and the box.

 

If that runs wel´ ld have a low cost and efficient way of stopping the printer if any bowden runs out of filament.

 

Greetings

 

 

Daniel

 

 

[Curven 28]

Hello I'm not sure I did understatd well but if you "just" want to detect the runout of filament you could use a switch (same as the enstops) in this type of casing:

https://www.thingiverse.com/thing:2845176

While there is filament the switch is in one state, and when filament runs out the switch triggers and pauses the printer.

 

As far as I know it is "easy" to do one UMO (+) and UM2 (+). But for UM 3 I don't know... Maybe there are some spare pins on the mainboard, but it need's a little bit of firmware modification wich is, as far as I know, not possible on UM3. (But my knowledge is very small)

[geert_2 557]

The thing is that a lot of spools are not transparent. They only have a small window, and they *do rotate*, and so does that window. So you can not see nor measure from the axial side how much filament there is still left on the spool. You would have to measure radially, thus from the top (sort of), and then calculated differences in distance by means of the reflected light, similar to a radar. And then calculate radiusses and circumferences for each winding, and the amount of windings. And then things soon start to get very complex. When you have spools that are very loosely wound, or materials that are very transparent, you are still likely to run into problems due to false measurements.

 

So, a paper label glued to the spool, or moulded-in indicators showing the remaining amount, seems by far the most simple and robust, even though very crude. But then, I am a simple man, so I prefer simple solutions. If there are problems, I try to solve them by taking their complexity away, not by adding extra complexity, because then it soon gets too complex for me.   :-)

 

Anyway, I have never been confronted with this problem myself, as my prints typically require 3 meters of filament. So when the spool is nearly empty, I just unwind the last meters and let them hang free. Very easy to estimate. But I understand this is not practical for large prints requiring maybe 30 meter...

 

[drayson 75]

some time ago, I also thought about something like this as I went out of filament just a few layers too early...

 

After a breif research, I found this design based on a load cell and a few electronics

https://www.thingiverse.com/thing:3054853

and a few other designs, which should be able to implement.

BUT - its not a simple solution...

 

On the other hand, there is something possible to use like a meter like this one https://www.thingiverse.com/thing:3945870

to count the consumed filament.

 

Nevertheless, if you find a nice solution, keep us updated... think this might be a nice addon 🙂

[geert_2 557]

3 hours ago, drayson said:

some time ago, I also thought about something like this as I went out of filament just a few layers too early...

 

After a breif research, I found this design based on a load cell and a few electronics

https://www.thingiverse.com/thing:3054853

and a few other designs, which should be able to implement.

BUT - its not a simple solution...

 

On the other hand, there is something possible to use like a meter like this one https://www.thingiverse.com/thing:3945870

to count the consumed filament.

 

Nevertheless, if you find a nice solution, keep us updated... think this might be a nice addon 🙂

 

For the spool holder with integrated balance: near the end of an old spool of stiff PLA, it may take 1kg (10N) to unload filament, to overcome the "spring effect" trying to wind it up again. Sometimes I can lift a nearly empty spool by the filament, without it unwinding. So, depending on the orientation of the pulling force, this might introduce quite big measuring errors, I think? This would especially be a problem where accuracy of the remaining length matters most: at the end of the spool. But at least this system provides a simple linear conversion between weight and remaining length, once the weight per meter is known. But this weight per meter would have to be changed per filament, otherwise printing with a metal-filled material might give unpleasant surprises. So it requires bookkeeping weights for each material and each color of filament (particle filled pigments like white might weight different from other pigments).

 

For the geared meter: where is that supposed to go? This is not clear from the pictures or description. I guess it has to sit on the feeder, or on the filament entering the feeder, so it measures the length that passes by? Definitely not on the spool, due to the varying diameter of filament while unwinding. However, how does this system handle switching spools? I switch colors and materials maybe 20 times per spool, before it is empty. Then how is this meter going to adapt to this, without a complex manual bookkeeping and resetting?

 

I think all this added complexity is prone to errors, and relying on it might cause more failed prints than just visually estimating the remaining amount, and using common sense. The best "guestimators" in complex varying situations might be humans.  :-)

 

[HaryPlotter 1]

To all of you,

 

thank you for your input so far. But I think I will define my thoughts a bit more in detail because I´ m not thinking of "tweaking" the spool but I´ m building a direct filament-trap...

I will attach a fast sketch of what I´ m about to construate. Then we talk again...

 

So far I got the Rasperry Pi yesterday.. I will set up the OS over the weekend. Then I could start playing around with the foto-diode...

 

But, unfortunately I won´  t get the Laser Diodes until the ! 16.12.2019 !. which for me is an eternity... ;O) so I can only start to draw the trap if I have this device because I lack the measurements for it...

 

Anyhow I´ m eager to set this up because it will eventually save me alot of pain when doing lager prints.

 

I will add the devices I already ordered for it so you can stay tuned...

 

Anyhow I am still at the beginning of programming so maybe someone can add up to the team with the programming of the python lines. This is the only thing that will probably eat up more time that I want... but for someone who is used to coding, this should be a peace of cake (Take a look at the drawing).

 

As soon as I get the last part for the trap I will start drawing some boxes in order to test the fitting of the devices and I need to find a spring that is not too tough and not too loose.. but that will be another task at the time.

 

Hope that you have my mind now..

 

Greetings

 

 

Daniel

 

PS: And if some UM-pro is comming around to see the progression of this task... I didn´ t find the direct command to set the printer on hold even though I looked in the API. There are only static values to get out of it or I at least could not find a specific command line that would set the printer from "printing" mode to "pausing"- mode. But at the fair the tech there told me that it should exist in the API. So maybe we can find that out as well....

[HaryPlotter 1]

Ok, now we´  re getting there. Slowly but still ok...

 

was to busy recuperating from work over the weekend so I could not find any motivation for the raspberry....

 

Yesterday that changed. So finally I managed to load an image to the board but couldn´ t try it because I overlooked to buy an adapter from HDMI to micro-HDMI. Small thing but it ruined my day. So today I got one and believe it or not: The smal PC is alive!

Then today I made all the changments and updates on it so I can start implementing the programme and the diode.

 

Finally I´ m waiting to get the Laser-Diodes. Once I have those I will start making a first sketch of the encasing because I can only start measuring when get this last piece.

 

Maybe I will start playing around with python in the meantime to get first results with the board and the fotodiode...

 

Now I´ m printing a basic encasing for the raspberry. I will adapt this device once the other things come to be implemented. But I will let you know then.

 

Meanwhile keep me updated if you have any good ideas with programming python, or if you have the code the brings the Printer from printing into pausing... or any other help that adds to this Topic.

 

Greetings

 

 

Daniel

[HaryPlotter 1]

Ok, now that we are all through x-mas and newyears time, party, headake and afterparty...

... I finally started to draw some basic sketches and make some prints.

 

Now the hardware is there and I could take the measurements according to the hardware and that is what came out (see fotos).

 

So now I have solved the hardware-problem (minus 1-2 issues --> The cover for the laser-tunnel is still missing but what the heck)...

 

I then did some testing and the installation worked fine. The only thing is that I had to organize some different size screws as the old ones holding the extruders will become 3-4 mm too short...

 

As of next month I will set me up a more comfortable way of programming my rasp (ordered a little touchscreen) and I will start to fool around with the programming software on it.

 

So again I hope I do´n t have to do everthing by myself... therefore it would be great I someone could help me with the programming of the rasp in order to get the fotocell to work propperly in conjunktion with the Laser LED.

I also researched the command for pausing the printer which can be executed directly from the programm over the rasp when the laser will hit the fotocell...

 

... will keep you updated on the project as it continues.

 

Greetings

 

 

Daniel