Question for users of E3D motion system
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Hi,
I'm seeking folks who...
- use the E3D motion system
- use the E3D tool changer system
- design their own tool mounts
Questions:
- Do you limit your designs to use the same tool offsets as the E3D tools?
- If not, do you limit your designs to use the same tool offsets for each tool if you are designing for different hotends?
Thanks much.
Frederick
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@fcwilt To answer your questions...
No and no.I have a e3d toolcjanger with four hemera based tools. Two "standard" ones using the e3d mounts and two modified ones which use a toolboard and a modified mount (and dock).
But I'm not sure why you would worry about the tool offsets, I'm pretty sure that even the two "standard" tools (the original V6 bowden and the updated hemera direct drive), use different offsets. When you fine tune the tools you end up with modified/different offsets anyway.
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When I first worked with creating the code to mount/dismount a tool it was with dummy tools with zero offsets and it was quite simple.
But now working with "real world" tool offsets the original code does not work and I am pondering how best to deal with the offsets.
If all tools were identical then zero offsets could be used with only the probe having offsets - but it didn't seem likely that all tools would be identical.
Frederick
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@fcwilt Sorry I'm not sure I understand what the problem is that you are having. Are you talking about the code in the free/pre/post macros or the actual tool offset definitions (set with G10)? I've not had any issues with either case.
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@gloomyandy said in Question for users of E3D motion system:
@fcwilt Sorry I'm not sure I understand what the problem is that you are having. Are you talking about the code in the free/pre/post macros or the actual tool offset definitions (set with G10)? I've not had any issues with either case.
The code in the pre and free macros to mount and dismount the tool. With the zero offsets of the dummy tools simple absolute G1 Ynnn moves were all that were needed.
Frederick
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@fcwilt The thing is that there are multiple offsets involved here, there is the coordinates needed to pick up/drop off the tool (so the ones in the pre/free files), but there are also the actual tool offsets (that define the exact position of the nozzle). Both can be different from tool to tool. I've found that even with supposedly identical tools to get a really good tool pick up/drop off you need to adjust the values used in the pre/free macros a little. There are a lot of tolerances involved with all of the various parts that fit together with bolts (some of which are printed parts). I suppose you could spend ages trying to ensure that each tool was identical and that the docks are in exactly the same place relative to each other, but it is much easier just to adjust the values in the config files. In my case the spacing for the docks are slightly different for the two tools that have toolboards so they need different settings anyway.
Do you have a toolchanger?
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@gloomyandy said in Question for users of E3D motion system:
@fcwilt The thing is that there are multiple offsets involved here, there is the coordinates needed to pick up/drop off the tool (so the ones in the pre/free files), but there are also the actual tool offsets (that define the exact position of the nozzle). Both can be different from tool to tool. I've found that even with supposedly identical tools to get a really good tool pick up/drop off you need to adjust the values used in the pre/free macros a little. There are a lot of tolerances involved with all of the various parts that fit together with bolts (some of which are printed parts). I suppose you could spend ages trying to ensure that each tool was identical and that the docks are in exactly the same place relative to each other, but it is much easier just to adjust the values in the config files. In my case the spacing for the docks are slightly different for the two tools that have toolboards so they need different settings anyway.
Thanks for the feedback.
Do you have a toolchanger?
I bought the basic E3D printer, the one with no electronics or actual tools. I have all the "changer" parts needed for 4 tools.
For now I am just picking up and dropping off the "empty" tool plates. The code that assumed no tool offsets worked fine but when trying to use that code from the tool pre and free macros that tool offsets specified for each "dummy" tool messed things up, as I expected.
When executing, say, a T1 command the tool offsets appear to be active in the pre macros. Correct?
When executing a T-1 command when exactly are the tool offsets no longer active?
Thanks.
Frederick
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@fcwilt just use G53 G1 ... To make your movements use the base coordinate system with no offsets applied. Then it doesn't matter what's mounted, you're always picking up and docking with the default coordinates
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@fcwilt one thing to try and aim for is two have only two z offsets for your tools (+/- a bit of tolerance). That way you don't need to make your nozzle wipers height adjustable and just have one on either side.
Otherwise @jay_s_uk answer is right - that's how I've got it on my TC. Means you can alter all the different tool offsets independently of the tpre/tfree macros
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@engikeneer said in Question for users of E3D motion system:
@fcwilt one thing to try and aim for is two have only two z offsets for your tools (+/- a bit of tolerance). That way you don't need to make your nozzle wipers height adjustable and just have one on either side.
That makes sense. Thanks.
Frederick
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@jay_s_uk said in Question for users of E3D motion system:
@fcwilt just use G53 G1 ... To make your movements use the base coordinate system with no offsets applied. Then it doesn't matter what's mounted, you're always picking up and docking with the default coordinates
Well that certainly makes things easy. I was going about it the hard way, trying to deal with the offsets applied.
Thanks very much.
Frederick
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@fcwilt I don't think any tool offsets are active during tfree or tpre macros (which makes sense), they do seem to be active when tpost is run though. I checked this at one point by inserting m114 calls into each of the pre/free/post files. The tool offsets are pretty large so it is easy to see that they have been applied.
I'm not using G53 in any of my files (nor do the various samples from e3d) and it all seems to work fine for me. Having said that G53 might be a good idea if you want to be sure what co-ordinate system is being used.
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@jay_s_uk said in Question for users of E3D motion system:
@fcwilt just use G53 G1 ... To make your movements use the base coordinate system with no offsets applied. Then it doesn't matter what's mounted, you're always picking up and docking with the default coordinates
Well I tried using G53 but it doesn't seem to be working as I expected.I set the Y offset of one of my "dummy" tools to 35 which will be correct for the current tool design I am working on.The code picks up the tool just fine. But when it goes to drop it off it reaches the dock as it should but the stepper keeps on running for a bit before it finally unlocks the tool and backs away as it should.The other three "dummy" tools which have no offsets work just fine, as expected.Does G53 work with firmware 3.3.0?Should the displayed positions on the DWC Dashboard be in machine co-ordinates or the tool co-ordinates? They are showing in tool co-ordinates.Any other thoughts on why the stepper keeps on running?~~Never mind - got it sorted - it was an error in my homing code that was not suitable for a multi-tool machine.
Thanks much.
Frederick
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@gloomyandy said in Question for users of E3D motion system:
I'm not using G53 in any of my files (nor do the various samples from e3d)
Hi,
Do you have a link to those E3D samples?
Thanks.
Frederick
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@fcwilt The e3d code is here: https://github.com/e3donline/RepRapFirmware-SD
DC42's version is here: https://github.com/Duet3D/RRF-machine-config-files/tree/master/E3D_Tool_Changer/dc42-duet3-centreZero-2Titan-2Hemera
He has (0,0) at the centre of the bed. I think both of these are a little out of date. The latest version of RRF (3.4) does not restore the tool position automatically at the end of tpost.Oh and I was partially mistaken in my previous post, it looks like the tool offset may be active when tfree runs (but not when tpre runs), both of the above examples and my own tfree files make use of G53.
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