Duet/RRF Big printing problems

deckingman

@pro3d Thus far I have been reluctant to offer advice to someone with the esteemed title of "R&D - Lead Engineering Designer - V-King 3D Printers" but you seem to be getting desperate so here goes anyway.

I think you should go back to basics. Stop trying to solve everything by printing one particular model and print test parts that allow you to find settings for parameters in isolation of other factors.

So start by find what temperature works best on this particular machine. Every thermistor is different. Using a realistic but modest speed like 60mm/sec, print temperature towers and pick the lowest temperature that gives you a good surface finish. Temperature is hugely important as it affect the viscosity of the material and therefore it's tendency to ooze out of the nozzle of it's own volition. Make notes and keep a record of why you selected a particular temperature.

Then move on to printing retraction test parts. There are numerous examples on thingiverse and everyone has their own favourite. I prefer just two simple cubes spaced some distance apart. Firmware retraction (M207) is ideally suited to this because you can make changes on the fly and observe the effect. You need to set your slicer to use firmware retraction and it will insert G10 G11 commands.

Start with zero retraction then gradually increase it until stringing and blobs disappear. Do not go too high as you run the risk of pulling molten filament back up beyond the heat break where it will solidify. Try different retract and un-retract speeds. If you retract too fast you can end up stretching the molten filament rather than pulling it back up. Make sure your extruder speed and jerk settings are sufficiently high that the retraction speed is not being limited. Once you have found the ideal retract/un-retract settings you can then either use those settings in your slicer or continue to use firmware retraction. Again, take copious notes and annotate your config.g so that in the future you'll know why you've chosen certain values.

If you are unable to completely eliminate stringing and/or blobs, then there are a couple of things you could try. I hesitate to make suggestions here as you must know the machine better than I. One possibility is that during your testing, you may have pulled some filament up into the heat break and whilst it hasn't caused a complete blockage, it may be restricting the throat so the filament isn't sliding as smoothly as it could be. So it might be worth running a cleaning floss through the hot end. I don't have any direct experience of using it but I am assured by someone who is very knowledgable about such things that it can work wonders. This is what I'm talking about https://rigid.ink/products/floss-superior-cleaning-filament

One other thing that will help if it's possible is to reduce the length or straighten out the Bowden tube. TBH, it's always going to be difficult to get good prints with an 800mm long Bowden tube bent in half the way it seems to be from the picture I've seen of the V-King. If you can find a way to take the extruder off the frame and mount it centrally above the bed, I believe that would work wonders. It might look odd but it would work much better.

You could also try using Capricorn tubing which is made to a tighter tolerance. I didn't have much success with it myself but my Bowden tubes are only about 150 mm long. Other people have reported noticeable benefits, especially with longer tubes.

Oh and you have eliminated and movement of the Bowden tube itself within the fittings haven't you?

HTH

bartolomeus

@pro3d It is not what I miss, but you are only providing small bits of information. If you want help from experienced users here, provide the information they ask. So post your whole config.g instead of just parts of it.

From your heater settings, if you have the standard e3d thermistor, these should be the right settings: M305 P1 B4725 C7.060000e-8 (https://e3d-online.dozuki.com/Guide/V6+RepRap+Firmware+Configuration/26?lang=en)

Your setting is different, but I can't tell if this will affect the sensor readings. Maybe others can.

pro3d

@monster-delta

Thanks but what am I supposed to do with M207 - where does that go and how do I use it - with G10/11?

Phaedrux

@pro3d said in Duet/RRF Big printing problems:

@monster-delta

Thanks but what am I supposed to do with M207 - where does that go and how do I use it - with G10/11?

M207 sets the parameters used for firmware retraction. To use G10/11 the slicer needs to be set to use firmware retraction which I described above for Cura which needs a plugin called printer settings.

pro3d

@deckingman

Thanks for taking time to write a long feedback on my troublesome journey. This time around I did everything by the book and kept it simple stupid from the configurator with no extra features or specials to test the plug and play experience

I will try to change my hotend as it is my last hope to find it was a component and not the firmware

I want this to be a plug and play experience as the marlin controller is for this machine printing beautiful with same setup so I am not going to use so much time on the detailed calibration that you suggest I am sorry. Then I rather just add back the 8 bit controller and print

It is a shame to have this expensive controller and not be able to use it and be outperformed by a 16 dollar controller so I will try to get it working without going so deep in the tank as you want me to - it should not be necessary for a decent setup

Firmware retraction
I still cant figure out how this is applied, it would be great to have
Components
I will try another hotend as I also mistake this new thing to be cluttered and see if it helps
I have ordered a new extruder as well
Bowden tube
The 800 mm bowden has been my friend long time with no issues with 6mm retraction in marlin no problem for 5000 hours at least. Does the rrf not support the same setup?
As of capricorn I have that as well but find it to tight and have a medial solution with 1.9mm as should work fine. Its the same as I have on the other machine
The play in the fittings has been eliminated

Thanks for trying to help me one more time

/roy

Phaedrux

Perhaps you can post your configuration.h from Marlin along with your config.g from RepRapFirmware and we can compare to see if there is something amiss. Without giving useful information to us, you are only complaining, and not actually trying to find a solution.

I explained how to enable firmware retraction twice now. Here is a 3rd attempt at explaining: https://forum.duet3d.com/topic/5993/firmware-retraction-tuning-with-macros

pro3d

@phaedrux

I am all about giving useful information but dont know what before someone ask for it so I am sorry if it seams complaining - I am troubleshooting like crazy for long time now trying to find a solution

How am I not trying to find a solution?

The link you now posted gives me new info. I did not se this before and I have to put it aside for later

Here are all firmware info:
https://github.com/RoyBerntsenDesign/V-King/tree/master/Firmware Files

Phaedrux

Thanks for the config files, I will take a look at them.

Next, what thermistor are you using and what parameters have you configured? If the temperature is being misreported that could explain the additional oozing.

pro3d

@phaedrux

Also did you see this thread? looks like identical issues
https://forum.duet3d.com/topic/3998/retraction-issues-800mm-bowden-bondtech-bmg

pro3d

@phaedrux

Thermistor is what comes with the e3d V6 - Semitec GT something and configured with the online tool
Edit: M305 P1 T100000 B4388 C7.060000e-8 R4700

Phaedrux

@pro3d said in Duet/RRF Big printing problems:

@phaedrux

Also did you see this thread? looks like identical issues
https://forum.duet3d.com/topic/3998/retraction-issues-800mm-bowden-bondtech-bmg

Yes, I saw that thread.

Did you try the retraction tuning as David suggested in the thread?

dc42 ADMINISTRATORS 5 Feb 2018, 06:26
Some suggestions:

Are the blobs are occurring immediately before retractions and travel moves? if so then they are probably mostly retraction-related.
Increase extruder max speed in M203 to 3600 (i.e. 60mm/sec), and configure 60mm/sec retraction in speed in your slicer, or in M208 if you use firmware retraction
800mm is a long Bowden tube, and you will need to tune your retraction settings and pressure advance well to get good results
What retraction amounts have you tried? With no pressure advance applied and an 800mm Bowden tube I would expect you to need around 9mm retraction. Less if you use Capricorn tubing and/or pressure advance.
With a Bowden tube that long, Capricorn tubing may help significantly.
It's probably best to tune retraction using the Lite 6 first, because if you use too much retraction with the all-metal V6 you are likely to get an extruder blockage. When you have found a good combination of pressure advance and minimum needed retraction, you can try the same combination on the V6.
I suggest initially you use no pressure advance, to find the minimum retraction you need to avoid getting zits just before travel moves. When you have found that value, add pressure advance (try 0.2) and see how much you can reduce retraction before the zits reappear.
HTH David

It also looks like someone commented that switch to capricorn tubing helped greatly for such a long bowden tube.

Phaedrux

@pro3d said in Duet/RRF Big printing problems:

@phaedrux

Thermistor is what comes with the e3d V6 - Semitec GT something and configured with the online tool
Edit: M305 P1 T100000 B4388 C7.060000e-8 R4700

That looks correct. Now have you run a PID tune on the hotend?

pro3d

@phaedrux

Yes PID has been applied

As of the tip in the thread I have not been digging to much into it. I disabled PA now to start over again so I will take a closer look. The tube I have should work just fine as for X1000 hours before I think? It is a 1.9mm tube I like to use as the Capricorn can be to tight for my taste

What I dont understand is that the proven settings from marlin will not work with rrf - like the retraction and speed and temp and everything. Does this have to do with that rrf use relative extrusion? Can I turn this off?

pro3d

@phaedrux

I will try to change the hotend. I mistake it has some issues although new

Phaedrux

@pro3d said in Duet/RRF Big printing problems:

Does this have to do with that rrf use relative extrusion? Can I turn this off?

Yes you can switch to absolute extrusion if you like. You can change the command in the config.g and also the slicer.

Phaedrux

Just looking at the differences between your Marlin and RepRap configurations.

E acceleration Marlin=10000mm/s^2, RepRap=1000mm/s^2
E Jerk Marlin=15mm/s, RepRap=10mm/2

This would greatly slow down your retractions.

So here is my suggestions for what to change and test next.

M556 E1200
M201 E10000

Set retraction to 9mm at 60mm/s with pressure advance off.

Print a retraction test model, every 15 layers increase pressure advance from the console by 0.05.

dc42

Your thermistor config is incorrect, it should be B4725. See https://e3d-online.dozuki.com/Guide/V6+RepRap+Firmware+Configuration/26?lang=en. That means you have been printing at the wrong temperature. HTH David

pro3d

@dc42

Thanks - Does this mean the config online tool gives another value than what it should have?

Phaedrux

@dc42 said in Duet/RRF Big printing problems:

Your thermistor config is incorrect, it should be B4725. See https://e3d-online.dozuki.com/Guide/V6+RepRap+Firmware+Configuration/26?lang=en. That means you have been printing at the wrong temperature. HTH David

The configurator gives M305 P1 T100000 B4388 C7.060000e-8 R4700 when The E3D Semitek-104 GT2 option is selected. It looks like that may have been correct for firmware versions older than 1.16, but the configurator seems to have not been updated to give the new values for firmware versions 1.17 and above.

I recently swapped a burnt out PT100 sensor for the E3D Semitek GT2 and used the values from the configurator for it, oddly enough I didn't notice any temperature related issues for the week or so I used it while waiting for a replacement PT100.

pro3d

@phaedrux

Nice catch about the E accel - I did not ever change this at any point in Marlin so I did not know its value. I will test your recommendations