Pro W - Extruder slipping

[JustinSB]

My Pro W Extruder has started slipping. It now makes a loud clicking sound. I have increased the voltage, which reduced the clicking, but alas did not eliminate it. I upgraded Marlin to 1.1.8, but unfortunately that made no difference at all to the extruder problem either. If I manually hold the extruder lever up, it reduces/stops the clicking - but, of course, it completely wipes out my print because I'm holding the extruder... I bought a cheap, metal, replacement for the extruder mechanism, but that also has identical problems.

Please advise how I should approach this problem.

I have been fighting this printer since the kit arrived in early December last year. I have yet to get a print off it that I am happy with. The pin on my 3D-Touch keeps on dropping whilst it's printing, which then catches on the print, which then wipes everything out. The linear bearings are, quite frankly, a complete disgrace. The started clanking, clunking & sticking, so I took everything to pieces yet again & one of the ball bearings actually fell out of the bearing & rolled across my desk. At the moment, I just want to try & stabilise my printer enough so I can actually print some new linear bearings - but I can't, because the 3D-Touch & the Extruder are even more shot than the bearings, & they're completely knackered. I've already had to replace the Z-axis with lead screws & the flexible mounts with ones that actually rotate true. Pretty soon, I'll have spent as much fixing this printer as it originally cost me to purchase it...

[William]

I have tried to upgrade my proB :
T8 rod for replacing the M8 rod

D2.jpg (173.35 KiB) Viewed 11895 times

1.Maybe the bearing of the extruder is not suitable?
A new one may fix the problem

2.Ensure the Z-axis does not exist huge wobbling

[JustinSB]

It turns out that it was a dead A4988 on the extruder. I replaced it, & it all started working again. I will continue testing things, & see how it goes.

[William]

Thanks for your feedback!

[JustinSB]

Also, the extruder skips as I am extruding into thin air, whilst trying to calibrate my e-stops. There is no movement on any of the X, Y or Z-axis. This is a 100% extruder problem, & has no connection to Z-Wobble or movement at all. Replacing the A4988 took me back to the stage where the stepper motor now skips as it tried to extrude (into fresh air, during calibration), so I'm back where I started from. I have tried replacing the extruder wheel on teh stepper motor, but that makes no difference. I have tried replacing the extruder frame, but that makes no difference either. I have had to replace the A4988, which hasn't stopped it skipping either.

What is left to try?

[William]

Have you tried to clean the throat and the nozzle?

[JustinSB]

I bought myself some new throats & nozzles, as they're easily & cheaply available. Alas, they made absolutely no difference. The symptoms are identical with both the old & new components, or if I mix them.

[Hermie]

I recently completed building my I3 pro b, I soon realised that the clunking I could hear was not wanted, after messing with the settings and getting little improvement I did some research on others having problems with the MK8 extruder. There is not a lot to go wrong with them but they do give trouble. I took mine apart and it looked clean and should be ok. But the clunking continued, then two things came to mind, one post talked about alignment, and I recalled a long thin rod that came with the kit and that no reference had ever been made to it. I stripped the extruder again after removing the filament, and carefully pushed the rod in the top where the filament goes, depressed the lever to allow it to pass the pressure gear and aligned it deep into the to of the long tube, there is a step inside so you have to make sure it goes down past that towards the hot end, lower the motor assembly straight down keeping everything vertical till you can insert the screws through the fan and heat sink with the rod still in place, gently tighten the screws, the rod should now be removed. My filament still fiddly to get in but I now don't get nearly anything like I had with only the occasional sound, which has been even more reduced by using a slower print speed, the model quality is now 200% better than it was with only minor stringing on corners, I use 210c for temperature to allow easier flow to, hope that helps.

[Shuflie]

Try increasing the pressure from the spring, I fixed mine by pulling the spring to extend it a bit then putting a screw into the bottom of the spring to increase the pressure applied to the bottom of the lever. All this presses the idle wheel against the filament harder and lets the teeth bite into the filament better. Since then I've been getting good filament feeding with the default extruder steps/mm.