Notifications
Clear all

INDX with cereal dryboxes  

Page 1 / 2
  RSS
jgorniak
(@jgorniak)
Active Member
INDX with cereal dryboxes

I keep all of my filament in individual cereal box dryboxes and successfully use the MMU3 with them on my MK4S. Footprint concerns aside, is it feasible to arrange 4 boxes on each side of the Core One+ feeding an 8 tool INDX system? I'm primarily concerned about the route and angles of filament going from the dryboxes into the printer. Seems like a lot of PTFE tubing to traverse.  

Posted : 07/05/2026 1:47 pm
hyiger
(@hyiger)
Famed Member
RE: INDX with cereal dryboxes

 

Posted by: @jgorniak

I keep all of my filament in individual cereal box dryboxes and successfully use the MMU3 with them on my MK4S. Footprint concerns aside, is it feasible to arrange 4 boxes on each side of the Core One+ feeding an 8 tool INDX system? I'm primarily concerned about the route and angles of filament going from the dryboxes into the printer. Seems like a lot of PTFE tubing to traverse.  

It's certainly feasible and I'm working on something similar for the Polymaker dry boxes. The question comes down to space on either side of the printer. Even though I'll have an 8 tool setup, I'll probably have no more than 4 or 5 mounted at any given time. 

Posted : 07/05/2026 2:55 pm
jgorniak
(@jgorniak)
Active Member
Topic starter answered:
RE: INDX with cereal dryboxes

Thanks for the reply. I finally found a short clip clearly showing the top of the C1+ with the INDX system installed. I was hung up on the filament insertion location being on the side of the regular printer. Seeing everything going in at the top resolves my issues and concerns. Thankg again!

Posted : 07/05/2026 5:50 pm
gb160
(@gb160)
Prominent Member
RE:

I’ve got mine mounted just above my C1, so I’ll be feeding from above, (irritatingly) my containers are going to be a couple of inches too low with the INDX turret lid i think, I’ll know for sure if we ever receive the kit 😂

I don’t think length of PTFEs is likely to be an issue, it’s more the tightness and number of bends you will have to watch.

Posted : 07/05/2026 7:28 pm
Jürgen
(@jurgen-7)
Famed Member
RE: INDX with cereal dryboxes
Posted by: @gb160

I’ve got mine mounted just above my C1, so I’ll be feeding from above, (irritatingly) my containers are going to be a couple of inches too low with the INDX turret lid i think, I’ll know for sure if we ever receive the kit 😂

I don’t think length of PTFEs is likely to be an issue, it’s more the tightness and number of bends you will have to watch.

But aren't there (presumably) filament sensors inside those mounting blocks which hold the four PTFE tubes, near the top of each side panel?

When I had my INDX preorder still pending I also intended to place a 4-spool dryer on a shelf above the printer, and I spent some (too much...) time wondering how I could retain that sensing functionality. Do we have any additional details on those sensors in the meantime? Or were they just a rumor, and those blocks are simply passive mounts for the PTFE tubes?

Posted : 07/05/2026 8:16 pm
gb160
(@gb160)
Prominent Member
RE: INDX with cereal dryboxes

They're definitely sensors mate, I've seen a picture where the wiring coming off each one is visible.

In an ideal scenario I'll have to remount/remix those sensor blocks into something that works from above.

Worst case scenario and I'll disable filament sensing altogether.

I simply have to have my filaments mounted above on the wall, as I'm not giving up the space on my desk for all those boxes... I sure as s**t aint paying out for those Prusa dry boxes, and having the filaments out and exposed to humidity isn't really an option either.

Posted : 08/05/2026 6:52 am
2 people liked
Jürgen
(@jurgen-7)
Famed Member
RE: INDX with cereal dryboxes
Posted by: @gb160

They're definitely sensors

Good to know, thanks! I am still keen to learn how Prusa achieves individual sensing for each filament with the limited I/O ports on the xBuddy board. Over the years they have come up with some clever retrofit solutions which enable unexpected functionality with limited resources. (And some awkward workarounds where is shows that the underlying hardware is pushed to its limits.) 

Posted : 08/05/2026 8:02 am
2 people liked
chmax
(@chmax)
Reputable Member
RE: INDX with cereal dryboxes

Given the limited amount available connections to the HW, if they need to retain single filament sensitivity I guess Prusa would need to multiplex the single sensor input with a counter that drives the 2x4 sensor batteries right and left... of all the various parts and pieces the calibration board and the run out sensors are the ones with the least info. 

Posted : 08/05/2026 8:26 am
Naugh
(@naugh)
Active Member
RE: INDX with cereal dryboxes

Probably taking advantage of the MMU3 connections.

Posted : 08/05/2026 8:27 am
gb160
(@gb160)
Prominent Member
RE: INDX with cereal dryboxes

I'm probably overlooking something here, but do they even need individual sensor inputs on the buddy board for all 8?

Only one can be used at a time, so if the switches are in parallel and one triggers the switch, the firmware will know what filament was being used at that specific time, and act accordingly ?

Posted : 08/05/2026 8:55 am
1 people liked
chmax
(@chmax)
Reputable Member
RE: INDX with cereal dryboxes

Good point. Still the core one has one input for the filament sensor and the indx implementation has two banks of 4. Even if the mounted nozzle will be associated with the sensor value, at least the two 4 banks would need to be OR'd somehow. 

Posted : 08/05/2026 9:16 am
1 people liked
Jürgen
(@jurgen-7)
Famed Member
RE:
Posted by: @gb160

I'm probably overlooking something here, but do they even need individual sensor inputs on the buddy board for all 8?

Only one can be used at a time, so if the switches are in parallel and one triggers the switch, the firmware will know what filament was being used at that specific time, and act accordingly ?

That would work if the sensors can send signals when (and only when) something changes. I.e. short pulses to indicate "filament has just been inserted" or "filament has just run out".

If they send state information instead, as a standard sensor does, you can't simply wire them in parallel or in series.  As soon as one sensor sees filament, the whole group would indicate "I see filament", and would be blind to changes on the other channels. Or, if you design with the opposite polarity, a single sensor that sees "no filament" would already determine the output for the whole group, and other channels could no longer impact the result.

Posted : 08/05/2026 9:29 am
3 people liked
chmax
(@chmax)
Reputable Member
RE: INDX with cereal dryboxes

Jürgen is very correct here: even if the logic is driven by the active dock, you will need to be able to read the status of each of the sensors otherwise it would be impossible to discern where the filament is loaded and where not. That is why I was thinking of adress-multiplexing, basically a background routine that update filament stati in mem by cyclic reading the sensors an address...

It will be nice to discover these things ince we have the kits 

Posted by: @jurgen-7
Posted by: @gb160

I'm probably overlooking something here, but do they even need individual sensor inputs on the buddy board for all 8?

Only one can be used at a time, so if the switches are in parallel and one triggers the switch, the firmware will know what filament was being used at that specific time, and act accordingly ?

That would work if the sensors can send signals when (and only when) something changes. I.e. short pulses to indicate "filament has just been inserted" or "filament has just run out".

If they send state information instead, as a standard sensor does, you can't simply wire them in parallel or in series.  As soon as one sensor sees filament, the whole group would indicate "I see filament", and would be blind to changes on the other channels. Or, if you design with the opposite polarity, a single sensor that sees "no filament" would already determine the output for the whole group, and other channels could no longer impact the result.

 

Posted : 08/05/2026 9:47 am
gb160
(@gb160)
Prominent Member
RE: INDX with cereal dryboxes

Well I presume they've found some way of achieving that @Jurgen. I've definitely seen a picture that shows the wiring from those blocks though...although I cant find it now.

Posted : 08/05/2026 10:17 am
Jürgen
(@jurgen-7)
Famed Member
RE: INDX with cereal dryboxes

It is straightfoward enough to implement state-change signals and connect all those with an OR gate.

But if you provide active electronics for that, you might as well make the sensors individually addressable, or readable as a sequential string. That way the firmware can know into which tube the user has inserted new filament and can start loading it automatically, or display an error message if a different tool is already loaded and is waiting for filament.

Posted : 08/05/2026 11:33 am
Remco
(@remco)
Active Member
RE: INDX with cereal dryboxes

I have a shelve above my core one with 5 polymaker dryboxes, my buffer and two ikea365 dryboxes. And that works just fine for me with my mmu3. I also noticed the wiring to the 2 filament sensors. the way they are facing is not ideal if you feed them from above, because of  the extra bends. So I hope the electic wiring has enough length to reposition them. On the underside of the shelve facing towards me would be ideal in my case.  i guess i can always make a few extension cords if necessary.

Posted : 08/05/2026 12:55 pm
Mchad65
(@mchad65)
Trusted Member
RE: INDX with cereal dryboxes

 

Posted by: @gb160

I’ve got mine mounted just above my C1, so I’ll be feeding from above, (irritatingly) my containers are going to be a couple of inches too low with the INDX turret lid i think, I’ll know for sure if we ever receive the kit 😂

I don’t think length of PTFEs is likely to be an issue, it’s more the tightness and number of bends you will have to watch.

When I was fumbling around with another brand's filament management system and polymaker boxes, I got some 3mm ID PTFE tube from Amazon, which dramatically reduced any internal resistance. Might help with long runs. 

Posted : 08/05/2026 4:46 pm
2 people liked
Patronics
(@patronics)
Eminent Member
RE: Filament sensor connections

I agree that I'm curious to see what solution Prusa ended up going with for all the extra connections for the INDX. One easy solution as far as the filament sensor goes would be to add a small microcontroller to monitor the filament state and report it over I2C. The nice thing about the I2C protocol is that it's designed as a bus that lets many devices (theoretically up to 127, in practice other limitations force lower amounts than that) all share the same 2 wires to communicate, with a single controller device (in this case the buddy board) able to command or poll the state of any of them at any time.

Posted : 08/05/2026 4:58 pm
1 people liked
Jürgen
(@jurgen-7)
Famed Member
RE: INDX with cereal dryboxes

Does Prusa already use I²C in the Core One? The load cell/filament sensor amplifier on the LoveBoard uses a proprietary serial protocol, and the temperature sensors are all analog I believe.

Posted : 08/05/2026 5:07 pm
ssmith
(@ssmith)
Estimable Member
RE: INDX with cereal dryboxes

Does Prusa already use I²C in the Core One?

The hackerboard is on the I2C bus...

 

Posted : 08/05/2026 5:18 pm
3 people liked
Page 1 / 2
Share: