Posts made by jens55

Just as an additional thought - how about mounting the extruders on a single plate with a swivel point in the middle. The idea is when one nozzle goes down, the second one goes up ... and vice versa. I am pretty sure that I have seen this kind of arrangement in a commercial setup before but I have no clue where I saw it. It was quite a while ago. The point being that you save some weight.

@3DPrintingWorld, 'spiking' would imply 'going high'. A short would not do that.
If this is just a terminology issue and you are referring to a temperature DROP then I would look at two aspects. How is the heater connected to the Duet? Are you using any connectors or is the only connector at the PCB. I have had many issues with connections overheating causing poor connection which then causes heating which then causes even more issues. Look at all connections to make sure the contacts are not discoloured.
I have also run into 'gentle' temperature dropping which can be caused by a defective thermistor. Rapid changes (ie instantaneous) could indicate a bad connection someplace since the hot end can not change instantaneously.
A defective thermistor might also cause sharp drops.
I have seen a number of issues and most of them relate to either the thermistor or bad connections on either the thermistor or the heater.

@Crosswire, don't know if it is related but on occasion I also get a blank page. It resolves itself quickly (might take 2 or 3 reloads). Today I had a blank page that did not resolve itself but I had no trouble with the same page on another computer (it was already loaded).

@MJLew, thanks again for your suggestions. This morning I collected the new print and there was only a tiny area that showed the same symptoms as the earlier print. It was a thing of (mostly) beauty!
I do not know what parameter change(s) caused the huge improvement. I forgot to mention that I had also added a tiny bit of support but that support was not in the problem areas but rather what PS felt strongly about.
I need one more of these fittings so I will get to reverse one or two of the previous changes to maybe narrow things down a bit more but my gut feeling is that reducing the speed was the cause of the improvement.
The next print will be started tonight for another overnight print.

@MJLew, thanks for the input. I have rotated the print and reduced the speed from 180 t0 100 mm/sec and started another print. It is a 6 hr print so it will be a while before I can see if there is a difference.
In retrospect, while PS does indeed slow down for bridges, I am not entirely sure this applies to overhangs in this part. Looking at the speed as reported by PS, it seems there was no slowdown. On the other hand, the overhang test sample did show a drastic speed reduction for the very outside filament laid down. It should be interesting to see how this next print turns out.

I am trying to print a 4 inch sch 40 45 degree pipe fitting. The fitting is printed with one open end flat on the build plate. Since this is a 45 degree fitting, I was under the impression that the most overhang I would encounter would be 45 degrees. Well this seems to not be correct for some reason or other that I don't really understand. I get severe artifacts on what I would think are the highest overhang portions.
I test-printed an overhang test piece with the chosen settings using PrusaSlicer and there was no distortion on the highest angled overhang which was 70 degrees (PS automatically reduces speed and turns the part cooling fan to 100%)
I also tried slicing the part with different settings of maximum overhang to see where PS started inserting supports and that happened at 75 degrees approximately.
I have a number of questions:
Since this fitting is a 45 degree fitting of a 4" pipe, are there actual sections where the overhang is more than 45 degrees?
Is there any other way that I can print this part without using a huge amount of support material? I tried different print orientations but that didn't get me that far.
Attached are a couple of photos of the artifact which to me look like a case of not enough cooling (I printed at 205C with PLA) but printing the overhang calibration print showed no difference between 205C and 195C.

@Phaedrux .... or turn the part cooling fan off during the first layer
My next job that requires weight is actually going to be done with sand and I will try to remember to turn the fan off.

@dlc60, I suspect that my closing the web control window and opening a new window does exactly the same thing that you accomplished by clearing your cache and cookies ..... but hey, it's a computer so what do I know
There is no question in my mind that there is a gremlin in the DWC system somewhere ......

I have a similar issue with a Duet2 WIFI and a Duet3 6HC. In my case, DWC slows down to unacceptable levels after having been run for a while (several days). In my case closing the DWC window and re-starting the web access brings speed back to normal.
This has been an issue for a very long time which has been reported in the past but no cause/fix was ever found. I have learned to live with it

@Phaedrux, while not impossible, I don't really know what I am doing. Could you give me a hint as to what you expect to see? There is no apparent (at least to me) difference in printer behaviour between a printer that shows hiccups vs one that doesn't produce hiccups. I don't know if maybe one would see choppy motion for example ... but there is no hint of choppiness.

I don't know if the hiccup issue is still being looked into or if it has been shelved. I just ran a 6 hr print using 3.5.1 and I am still seeing the same issues. Here is my m122 for the tool board that did the printing. Note the 'hiccups 27753'

m122 b22
Diagnostics for board 22:
Duet TOOL1LC rev 1.1 or later firmware version 3.5.1 (2024-04-19 14:42:41)
Bootloader ID: SAMC21 bootloader version 2.3 (2021-01-26b1)
All averaging filters OK
Never used RAM 3104, free system stack 71 words
Tasks: Move(3,nWait 7,2.2%,85) HEAT(2,nWait 6,8.9%,91) CanAsync(5,nWait 4,0.0%,55) CanRecv(3,nWait 1,2.5%,71) CanClock(5,nWait 1,0.6%,59) ACCEL(3,nWait 6,0.0%,53) TMC(2,nWait 6,90.6%,53) MAIN(1,running,38.8%,315) IDLE(0,ready,0.0%,27) AIN(2,delaying,122.4%,112), total 266.0%
Owned mutexes:
Last reset 97:43:37 ago, cause: software
Last software reset time unknown, reason: AssertionFailed, available RAM 3392, slot 1
Software reset code 0x0120 ICSR 0x00000000 SP 0x2000415c Task Freestk 129 bad marker
Stack: 00000544 00022ffc 00019b65 20003134 00016cff 20003134 000163d1 20000ed0 00000000 00000001 00008275 200071c8 200071c8 200071e0 00000000 20000f50 00011647 000223b8 00022474 00021ac8 00019b05 200071c8 200071c8 20000f50 000083ed 200071d8 000009c7
Driver 0: pos 0, 830.0 steps/mm, standstill, SG min 0, read errors 10, write errors 0, ifcnt 225, reads 7857, writes 3, timeouts 32, DMA errors 0, CC errors 0, failedOp 0x6a, steps req 0 done 73029969
Moves scheduled 394767, completed 394767, in progress 0, hiccups 27753, segs 33, step errors 0, maxLate 1 maxPrep 495, maxOverdue 136, maxInc 71, mcErrs 0, gcmErrs 0, ebfmin 0.00 max 1.00
Peak sync jitter -1/4, peak Rx sync delay 272, resyncs 0/0, no timer interrupt scheduled
VIN voltage: min 17.7, current 24.4, max 24.5
MCU temperature: min 32.8C, current 36.1C, max 54.4C
Last sensors broadcast 0x00000004 found 1 26 ticks ago, 0 ordering errs, loop time 0
CAN messages queued 1831836, send timeouts 0, received 2249695, lost 0, errs 0, boc 0, free buffers 18, min 17, error reg 0
dup 0, oos 0/0/0/0, bm 0, wbm 0, rxMotionDelay 561, adv 35643/74674
Accelerometer: LIS3DH, status: 00
I2C bus errors 0, naks 0, contentions 0, other errors 0
=== Filament sensors ===
Interrupt 5726621 to 0us, poll 5 to 2912us
Driver 0: ok

@nick9one1, just because you took a brand new roll out of a vac pac, this is no guarantee it's dry.
I have had new and wet filament straight out of the bag.

Have you tried drying your filament? I know that PLA is not too sensitive to moisture absorption but I have had some very surprising results happening with drying.

@jay_s_uk
I use Dragon hot ends on all my extruders and have never run into an issue where heat creep caused any issue.

@Juan-Estanislao
Nice build! Sorry, can't help with the question.

@travasky, that is the proper way to go .....

@travasky
I too have a chamber heater that needed a fan. I do not consider it safe to run the fan control from the printer controller unless there is some sort of safety that is preferably totally independent of the controller. In my case I opted to turn the fan on whenever the heater is on (turned on by the power to the heater). My heater is a PTC heater so it has a bit of a built in safety.
Another option is to run a second fan that is software controlled that you can run during the entire print to circulate the chamber air.

@dc42
Alas, that fix did nothing to my hiccup problem

@droftarts
Do I just upgrade the .bin files? What are the .map files for? Do I just upgrade MB6HC.bin and Tool1LC.bin (I only have the 6HC and the 1LC boards) or do I need to upgrade other stuff?

With the .bin files uploaded, this is what I see for the version information:

Nothing seems to have changed on the 1LC firmware and only the MB6HC firmware changed. Is it ok to have three different versions of firmware (between the 6HC, 1LC and DWC)?

@dc42, could this bug that you just squashed also be causing my huge number of hiccups as well as the bogus Vin min/max numbers?
I noticed that a few of the M122 Bxxx reports posted in this thread also have large number of hiccups (although not as large as the ones I am seeing) as well as the bad voltage readings.
Please advise on what files I should upgrade to implement this fix so I can try out if it maybe fixes my issues.