3DSolex kit on Ultimaker 2 extended

[my3DBr 4]

Hi

Yesterday I installed the 3DSolex Kit - heater block, 0.4 nozzle, PTK spacer and I2K insulator, original heat cartridge with thermal paste. It states that I can print with a lower temperature but with the same temp than before I am getting heavy skipping steps.

I have a UM2E with original extruder stepper motor (0.9º) coupled to a DDG Bondtech via a adapter found on YouMagine. 

When I installed the DDG I don’t know why I got missing steps also - I could never understand why, since the Bondtech DDG is geared.

I’m running the last stable Tinkercad firmware.

Any clues?

Thank you.

[Torgeir 228]

Hi @my3DBr

 

How many E-steps are you using with this setup?

They advice E-steps for an UM2+ to be "311", but this is for an 1.8 deg/step motor. (200 step/360 deg)

Found here:

https://www.bondtech.se/product/ddg-extruder/

 

As you have the old stepper (from UM2E) that's 0.9 deg/Step. (400 step/360 deg)

According to this, -you'll need to double the number of steps by 2, I.E. E=2*311E=622 E-step, for your setup.

 

If the E-step setting is too high, the stepper may miss step.

Also, if the current setting is too low you may see missed step.

Normal current setting for the feeder stepper motor (E1 or E2) is 1200 mA.

 

Thanks

Torgeir

 

 

[gr5 2,070]

1) What Torgeir said about the steps/mm.

2) The bondtech is skipping?  Really?  Is the tension half way up the scale as described here? http://www.bondtech.se/wp-content/uploads/2018/08/Bondtech-DDG-Ultimaker-V1.0.1.pdf

 

Is it possible the filament is slipping through the feeder and the stepper isn't actually going backwards?

 

3) When you use the i2k you should cut off part of the teflon part by the same amount.  So if the i2k is 1mm thick then slice off 1mm from the teflon part.  If you don't do this - particularly on the "plus" series printers like yours, that aluminum spacer can't compress and you have MUCH too much pressure on the teflon and it tightens/pinches/grips around the filament.

 

4) Is your teflon part new or old.  You say it is "PTK" but I'm not sure what that means.  There is the Ultimaker spacer and the 3dsolex spacer - both are great but need to be replaced regularly (like every 200 to 500 hours of printing).

 

The easiest way to diagnose is to put the filament half way down the bowden.  Have the extruder move it forward with MOVE command and then fight that with your hand by pulling down on the filament just below the feeder.  You should be able to pull 5kg or 10 pounds of force without the feeder skipping.  If it skips then something is wrong with the extruder.

 

If it doesn't skip then it's the print head.  I suspect the print head but it could be either.

 

[my3DBr 4]

Thank you guys.

Here is the thing:

A. I have calculated de e-steps accordingly, it seems right (at 652.92) - extruding 120mm, seeing what's left etc...

B. I am using tinker gnome and the current for E1 is set at 1250ma.

C.2) Yes, the tensioner was way up, leaving it's grip soft.

Yes, you are right, it seems the filament slips through the bond tech gears making a weird sound that was not the motor skipping steps (although very similar sometimes).

I disassembled the extruder to see if I could find something, and I think that due to a high pressure in the Bowden the filament tends to curve and then it dislodge both gears, taking them apart and loosening the pressure making the weird sound.

Why am I getting such pressure inside it?

3) I am using the 3D Solex combo I2k insulator + TFT255C PTE Coupler. Brand new. I really did not know I has to cut a peace of the teflon out, since at the 3D Solex site is states "Usage: Unplug PTFE from steel coupler, insert I2K, re-insert PTFE. Finished.  Steel coupler must be turned all the way down to block, and only half turn back up allowed for sync in dual setup."

And that was it. I screwed the coupler all the way, inserted the insulator, then the new special PTFE. The spring is very compressed - I don't have that spacer, still going with the spring.

So as you say, it might be the pressure on that system caused by not cutting a piece oh the teflon, reflecting on a hight pressured extrusion?

[Torgeir 228]

Hi @my3DBr,

 

I'll think @gr5, nailed your problem.

 

You should get read of that spring and use a steel spacer -as it will increase the life length of your coupler(s).

 

Thanks

Torgeir

[my3DBr 4]

Thank you for your time @Torgeir. There is one last thing to experiment: the extruder force. I am going to make the @gr5 experiment and give you some feedback. And print or buy said spacer.

Edited August 2, 2021 by my3DBr

[Torgeir 228]

You're welcome.

I printed this spacer, however it started to crimp due to the heat -so I just bought the spacer to avoid leakage..

With your new Bondtech, I'll think a steel spacer is a must -due to the hi pressure it can make.

 

Good luck.

Torgeir

[gr5 2,070]

I think the spring is better than the spacer personally.  Just slice off a bit of the teflon and that will help quite a bit.

 

If you do want to print a spacer, I designed this one and it works quite well in ABS (I have green abs filament):

 

https://www.youmagine.com/designs/um2-spring-replacement

 

But really the spring is great.  It's very powerful so if you compress it an extra 2mm thats... too much.

[my3DBr 4]

Appreciated guys. So @gr5 you really think that I have to slice a piece of the Teflon out? Better slice the old PTFE or that brand new modified from 3D Solex? Maybe try it out with the old one (it is in good condition) first?

Edited August 2, 2021 by my3DBr

[my3DBr 4]

I’ll send some pics later when I get home.

[gr5 2,070]

Don't "test" the teflon based on how it looks.  Push hard on the end that gets hot and see if it is softer.  If it deforms easier.  Push very hard.

 

If you are just trying out the i2k I suppose only cut one of the teflon parts but then if you like it you can cut all the teflon parts going forwards.  Of course you should never need to buy another if you keep temps below 300C.

[my3DBr 4]

I am afraid to get it wrong and ruin the special Teflon - for me from Brazil it is expensive and takes a long long time to arrive…

The grate advantage for me is to avoid repetitive maintenance. Aiming to print in PLA and ABS (just bought a door for “enclosure”) although I did not printed ABS yet. So, yes, temps below 300 C.

That is what get me: a time proof set.

Edited August 3, 2021 by my3DBr

[gr5 2,070]

Well you really have to do it to one of your teflon parts.

 

Ultimaker considers the teflon an "expendable" like filament.  The expect you to buy a new one with maybe every 3rd order of filament?  I'm not sure what they expect.  Because it is expendable, most companies (think inkjet printers) would charge extra but Ultimaker does the opposite and sells these at a very reasonable price.

 

Anyway I would definitely cut the teflon on one of these.  Carefully.  With a razor blade style knife.

 

I would do it to the used teflon because you will mostly be throwing away the "bad" part of the used teflon.  The teflon stays mostly new except for the hot end.

[my3DBr 4]

That is a good way to think about it. Thank you gr5. As soon as I get some time I'll do it. 

[my3DBr 4]

So what was happening is I was using a POM 3rd party stepper motor gear, not the original, it was bended, pushing the central DDG gear aside at that bulged point, thus leading to disconnection to the lever gear. A false skipping step. I had two options: using a metal one or printing one. 

I put the metal one, but since I think the original is made of plastic, am considering changing it to the printed one. What do you think?

[my3DBr 4]

Hello everyone.

I have news!

My printer had a Achilles heel: I never ever thought about changing the heater cartridge...it was the old original, 25W if I am not wrong.

It happens I am a often customer from AliExpress and had a 40W heater lying around. 

Here comes the story: as you can imagine this is not a 3DSolex or other know brand, so I had two problems: it was short for the Extended version AND the cartridge is skinnier  (0.1mm) then the original - the hole in the heater block is 5mm, the good quality cartridge 4.9mm, the Chinese 4.8mm (I've read that it is proposital since Chinese or second quality blocks have problems with accuracies). So I had to sold wires (from another cheap cartridge) and do a little smashing with pliers so it deforms a little bit.

Then I've put some thermal paste to fill the gap and voialà, all set. 

Everything working grate! PID tuning and some stress tests, no extruder skipping, everything good!

 

I went searching all again for good quality heater cartridges and had the same problem, even on first line sellers: they don't tell the wire length.  How to know if it fits the Extended version? Send some emails around to see what happens.

I went back to AliExpress and finally found PT100 thermostat AND 40W heaters with 1.5m long cables. Just bought them.

[my3DBr 4]

I still have a significant leak of plastic in the junction nozzle/block from 3D solex. Have read somewhere that this is because of the plating.

Now I am reading around social networks some people saying they had problems with the print due to the matchless nozzle.

I am starting to think maybe I spent some money wrong.

Will compare print with other nozzles.

[my3DBr 4]

CHt nozzles have some success as it seems…