I was able to solve the problem myself - so this is for anyone who might stumble upon the same problem in the future.

The problem was the inertia (momentum) of the filament spool. The filament spool is held by the famous "Universal filament spool holder" that uses two ball bearings at each end and is extremely easy to move. So when the extruder has faster moves - it pulls the spool and it's inertia pushes the filament a bit more through the sensor than it is actually going into the extruder since the filament can bend and straighten - hence it all makes sense - that sometimes there is more, sometimes less filament going through the sensor - but the average is always exactly the amount that went into the extruder.

The solution is to constrain the filament path before and after the sensor - either by a tighter PTFE tube on both sides or maybe by a sponge filament cleaner at the entrance of the sensor.

If you are using the "Universal filament spool holder" - you can also put two PTFE washers on the sides of the ball bearings and squeeze them a bit with a locking hex nut - that would prevent the spool from rolling more than requested, but would still roll nicely.

Now my readings are normal.

Hope it helps someone having the same problem with the laser filament sensor.

Just a short update from my side about the Bigtree filament sensor.... It works as intended now!

My settings are M591 D0 P7 C"e0stop" L7 R75:125 E22 S1

The readings are usually from 93 to 108%, but I keep it on the safe side with the 75/125 % min/max settings.

It already saved one print....

Hope it helps.

Hi guys,

I didn't have time to go through the whole thread, I just read parts of it, but since my friend @arhi mentioned my experience, I just wanted to confirm it.

I've been printing a lot of different PLA / PET-G brands with the original Mosquito and it has been performing like a champ - I did not have a single problem with it. Before that I was using an MK11 Microswiss all-metal hotend and it was honestly a pain. When it was working- it was performing ok, but when you want to swap a nozzle for example - that is when the nightmare starts - it was a lottery if it would clog or not and cleaning the whole system was painful.

With Mosquito, swapping nozzles is a breeze and I do it every other day now, to switch between detailed and big prints. I was "expecting" it to fail at some point, since there were some prints that were 24+hour long - but it did not. The only "issue" I've had is that when printing with a 0.8 nozzle with high layers - you have to lower the speed to 30mm/sec if you want to avoid underextrusion, but that is understandable, and you have the MAGNUM version if you want to go faster with bigger nozzles.

Anyway, if you can afford the Mosquito - I would say go for it. I will be upgrading to the V2 mosquito magnum in the following days for sure.

Hope it helps.

I've designed a case for Duet 2 + Rpi + 7" screen + 2x SSR's for custom dual zone bed heater. Here is how it looks like

@Veti Yup, as Arhi said - if your fans are rated the same voltage as your VIN run them in parallel. If they are half your voltage, run them in series - and you might want to put a zener diode on each end of the series just to protect the fans. That's how I am using these two beefy 12v blowers on a 24v VIN

@Popstar
No additional electronics is needed. It works as is - without any problems - just make sure you get the pinout right and put this line to configure the sensor :

M591 D0 P7 C"^e0stop" L7 R50:250 E22 S1 ;pulse, disabled, 7 mm/pulse, measure every 22 sec, minimum 50 maximum 250

Also it would be wise to disassemble the sensor and "squeeze" the spring a little bit, to make the filament go through more easily, since by default the spring is too strong and puts a lot of resistance to the filament flow....

Hi guys,

I am having a weird problem with setting the z-offset for BLTOUCH (DUET 2 ethernet, RR 3.1.1).

My default z-offset for bltouch in this setup was 1.2mm (y offset is 0, x offset is -20) and I started with that.

But no matter what value I set for the Z-offset, the Height map is shown below the the X,Y,Z grid (see the picture below) and I when I do the G29 mesh calibration it shows the warning that there is a substantial Z-offset.

I've tried calibrating the trigger height using the instructions here, but I am still having the same problem.

When I try the G0Z0 at the homing position - z goes to the proper height I set for printing.
But when I start the print it usually starts way too high.
I tried both lowering and raising the Z-offset but nothing seems to solve it.

I also have dual-z leadscrews with dual motors - set to do true bed leveling for the x-axis.

Does anyone have any ideas?

Here are the config.g, home.g and bed.g attached

config.ghomez.g homey.g homex.g homeall.g bed.g

@zapta

Thanks for the answer.
I've tried it yesterday - but it seems that Duet is not recording any data from the sensor.

I configured the sensor as following, just to log data when printing :

M591 D0 P7 C"^e0stop" L0.07853981634 R90:110 E3 S0

but it did not receive any data.

Any ideas on what I can try is highly appreciated.

Thanks again

@jay_s_uk I've just ordered one.... looking forward to testing it.

@JoergS5 Thanks for your time man, I really appreciate it.

Here is the image of the mesh :

Not much was changed, I added a laser filament monitor (but that shouldn't be a problem) and also added an additional 40mm fan to cool the extruder since the stepper motor is encapsulated in the carriage so I was afraid it may be overheating.

As for the config.g the only I was mainly changing is the z-offset since I cannot seem to get the first layer at the correct height. One thing that is really bothering me is that G32 (true bed leveling) is doing adjustments each time I run it... even when the printer was not turned off.

Another thing I have tried is the z-probe repeatability macro and the deviation from the mean last time was 0.005, so it is working. I also set the following line for thr Bltouch :

M558 P9 C"^zprobe.in" H5 F300 T6000 A4 S.0.03

Images of the printer:

@SDJ
If that is true, it's really good news. It sure seemed like it had become abandonware.
I definitely prefer Superslicer to anything else I've tried.
Each slicer has some things that are cool, and others that are kind of annoying or lacking, but SS was definitely the sweetspot, at least for me.

@omni Yea, another great thing about this method is that my gasket was actually quite complex - it had multiple points of contact on the lower side, so it was not a simple O-ring (more like a 3D o-ring) and I could not find a replacement anywhere. So you can make even complex gaskets.

I tried TPU printing, but anything below 70A is actually quite tricky to pull off nicely. especially if it's a bit complex, and there is always the seam issue with FDM, layers, tolerances, etc. For gaskets - printing a resin mold and using a purpose gasket compound is the way to go.... it also tolerates temperatures up to 200c, does not deform from water exposure and high pressure, etc.

@jens55

The idea was to put more material than needed (tighly packed into the mold straight from the tube) and then just compress it and let the extra material and and some air flow out of the holes.... It turned out great actually, just needed a bit of sanding where I cut the excess, but it's a 3 minute work.

For the mold release I used a puropse mold release wax (usually used for resin pouring) but since this RTV is silicone based, you can probably get away with a few drops of fairy dishwashing detergent spread all over, since silicone does not stick to it at all....

And one important thing, my mold was printed on a resin printer, so the tolerances were very tight and precise and the surface finish was excellent.

@jens55

Can't find the original file for the gasket mold, but I skecthed something fast along those lines.....

Fill the light gray part with rtv, push the dark gray part inside, the excess goes out from the holes.... when it cures, you just cut it out with a scalpel.

But you need to do it fast while it's still viscous, since it cures quite quickly.... Also my gasket was rather large, so I guess it would be a bit difficult to squeeze it out if the holes were very small....

@jens55 Well, with the rtv I just kind of overpoured it into the mold and made a mold in such a way that it squeezes out the excess... Then when it cured I just did a little bit of postprocessing with a scalpel / rotary tool. Don't know if there were any significant air pockets but it sure worked well enough, and going strong for more than a year now. The second one is pretty much liquid, you can pour it easily. I still haven't used it but it was recommended to me by a person who uses it regularly so I bought it as a backup option. Didn't yet need it since this rtv worked great.

@jens55

If you can, get one of these products:

Just print a mold, use some mold release, and you will make a perfect gasket.

I did not read the entire thread, but also make sure the 3d printed part itself is waterproof. Print it solid or dip it in resin after printing to make sure it's 100% waterproof. I made some critical parts and gaskets for a waterpump and it took me some trial and error before I made it 100% reliable.

@button Thanks, good to know. I was hesitant to try it out since it looks mainly Klipper oriented, but I'm gonna go ahead and set it up...

@jens55 Well yes, you might be right if it's a small by surface but very thick bed and well insulated it might not make such a big difference. I have a 525x525x6mm bed and it warps like crazy when heating / cooling. It can be +/- 0.5mm difference in corners. That is why I adjust and probe the bed only when fully stable at the printing temperature. But I don't think there is a need to turn off the bed while probing if you are using bltouch. For some other types of probes maybe...

@jens55 Well that may well be your main problem - you are probing a cold bed or a hot bed which is cooling during the probing since your bed heater is off. The aluminium plate can warp and fluctuate in height BY A LOT in just a matter of seconds depending on the isolation, much more than the problem of accuracy of the probe. Before you probe the bed you need to make it stabilize in tempreture and keep the printing temperature of the bed (preferably with PWM) at all times during the probing in order to get the most accurate results. Probing it cold or during cooling is pretty much useless if you are looking for very high accuracy during printing. 0.003 repeatability is plenty, those are not values that you are going to notice. But bed height fluctuating +/- 0.3mm because of the cooling you are definitely going to notice...

@jay_s_uk I've just ordered one.... looking forward to testing it.