IDEX Support

iDevelo · 19 Oct 2016, 20:51

Can E1 be the U endstop? I use E0 for my Z microswitches.

dc42 · 19 Oct 2016, 21:35

No, E0 has to be the U endstop. If your Z microswitches are normally closed and you are using them to implement Z probe type 4, you can connect them to the Z probe connector and select type 5 instead. I may also add an option to connect a switch-type Z probe to the E1 endstop input when there is no V axis.

iDevelo · 20 Oct 2016, 06:43

Ok thanks. I'll give that a try.

With IDEX I have a micro switch on each carriage that can measure the height of the bed and make it easy to level.

So am I thinking right if I switch from T0 to T1 and viceversa in gcode the Z offset will be applied for that nozzle and move the bed up or down?

dc42 · 20 Oct 2016, 06:47

@iDevelo:

So am I thinking right if I switch from T0 to T1 and viceversa in gcode the Z offset will be applied for that nozzle and move the bed up or down?

Yes.

T3P3Tony · 20 Oct 2016, 09:16

I have two IR probes, one on each carriage. I plan on levelling the bed with one and then using the other (on the U axis) to set the second extruder Z offset.

In the long term I can envisage a Idex system that can automatically determine all the offsets by scanning the bed which has a variably reflective pattern at one point. Or anyone head printing a pattern and the other head scanning it with the probe.

Anyway, the probe on the X axis carriage is connected to the probe header, currently the on in the U axis carriage is connected to the Z end stop, is this correct?

iDevelo · 20 Oct 2016, 11:51

My glass is raised 10MM off the alloy bed. The alloy is 550x550 and the glass is 450x450 so i have enough room around the glass to use switches. The switches are on each carriage about 5mm above the nozzle. The carriages move the the edge of the glass and lower down until they hit the switch. I then get the Z reading.

To level i use a 3 screw system so i only ever have to adjust the front 2 screws. The routine probes the back left corner of the glass and sets Z0. Then the front 2 corners are probed and i get the 2 readings i need to level the bed.

Now i'm going IDEX i will have a switch on each carriage. It will allow me to level the bed and also set the Z offsets for X/U easily.

T3P3Tony · 20 Oct 2016, 14:49

That sounds like a good design. There is not space in the BigBox for that configuration but the probes should allow me to do a similar thing.

That said if I want to print two objects at once, one per axis, then I need to have the Z height identical for each nozzle

Alex9779 · 20 Oct 2016, 15:10

@T3P3Tony:

That said if I want to print two objects at once, one per axis, then I need to have the Z height identical for each nozzle

But I see issues there on the BB because per design the extruders are fixed, you can't adjust them. Well maybe be pushing and pulling but there is no mechanism. So if the offset is too big, lets say more than a layer height, then you will have hard times doing so.

dc42 · 20 Oct 2016, 16:01

Can the BB design be changed to provide a height adjustment on one carriage? It would be a shame not to be able to print two identical objects at once. Could one of you raise this on the BigBox forum?

Alex9779 · 20 Oct 2016, 16:38

Well you could make long holes on one X carriage but that you be a pain to level I think. Best would be to decouple the extruder mounting from the bearing mounts with a part between which can then be height adjusted…

T3P3Tony · 20 Oct 2016, 16:42

The design could be modified. one simple way that might work is to make the extruder motor mounting hole elongated. Then start with them slightly loose and rest both hot end tips on the bed in the centre (one the bed is levelled for the X axis). then tighten up ensuring the tips remain incontact with the bed. The one issue with this is one of the titan mounting screws is obscured by the hotend so tighten 3, then remove hotend and tighten last one, replace hotend, and test.

A complete carriage redesign, that allowed for quick swapping of tools would be good anyway so maybe it could be incorporated into that.

T3P3Tony · 20 Oct 2016, 17:33

In fact you would only need to do this for one carriage, which I will do and report how it works

Alex9779 · 20 Oct 2016, 18:01

Yeah it is doable that way, but will hate it ;). Mounting the Titan and have no clicking sound when retracting is not easy and if you wanna move it up and down to level it against another hotend by +-0.05mm… Well I will hate it...
But printing multiple copies has no priority for me so I will go with the fixed ones first, I want support prints...

T3P3Tony · 20 Oct 2016, 19:28

Yes its a total hack but It will allow me to get the printer to the point I can print two objects at once - the full carriage redesign will take time.

iDevelo · 20 Oct 2016, 21:30

Oh so we have the ability to mirror the print and use both extruders at the same time?

dc42 · 20 Oct 2016, 21:38

Yes, see https://duet3d.com/wiki/Configuring_multiple_independent_X-carriages_on_a_Cartesian_printer#Miscellaneous.

iDevelo · 20 Oct 2016, 21:41

Awesome! I'll make sure both are the same height then

dc42 · 21 Oct 2016, 15:25

I have a put preliminary build of firmware 1.16 beta 4 at https://dl.dropboxusercontent.com/u/19369680/DuetWiFiFirmware.bin. This supports X axis mapping. So you should now be able to do dual material and mirrored prints on IDEX machines.

Some notes:

1. I have updated the sample tool change files on the wiki page. In particular, you should not use the G1 R2 commands in the tpost#.g files that I had in the earlier version.

2. The reported coordinates are raw, which is deliberate. So the X coordinate shown by DWC is that of the physical X axis regardless of any mapping. Same with M114. If you have a PanelDue and you put the latest 1.15a firmware on it, you can see the U coordinate as well. Eventually, DWC will show the U coordinate as well.

3. Make sure that the commands in your homing files that cause the head to back off a few mm after dong course homing have the S2 modifier on them, so that X mapping will not occur on those commands. Similarly, any command you have in homez.h or homeall.g to put the head in a particular position prior to doing a G30 probe should have the S2 modifier to ensure that you put the X carriage there and not the U carriage.

4. I suspect there will be a few glitches, such as additional places where X mapping needs to be done. Most likely they will occur when changing between tools. This is something that I can't test fully, because I don't have a dual carriage printer yet.

iDevelo · 21 Oct 2016, 16:37

Ok I'll keep you updated with my progress and report any issues.

I should get some movement this weekend but I doubt I'll beable to print as I'm waiting for a bondtech extruder to arrive. My main aim is to get X/U complete and test homing and bed leveling.

I have plenty of time next week to complete this.

Thanks for your hard work

T3P3Tony · 22 Oct 2016, 19:31

I have mirrored printing working on by BigBox IDEX system:

I made a few changes to the Wiki so if you are working on this make sure you are using the most up to date examples from there. My configuration does not differ from the example on the wiki other than for steps/mm dimensions and other printer specific stuff.