Make sure that the idler wheel is very tight against the filament (if you can't see the idler wheel moving you are not getting a tight grip on the filament) as you can tighten it more than most person's would normally think, just be somewhat cautious of cracking the acrylic or you may have to give the printed part I made a try.  Make sure you are using a hot enough temp.  200 is more than enough.  I use 190-195 normally as per my thermistor.  210 for clearing clogs and don't go higher than that.

I used to use this approach, tightening the idler spring right down until it was totally compressed, and then backing off a turn or so.  I now keep the idler spring set so that almost none of the screw shows (i.e., much looser).  This seems to have fixed some problems I was having where the extruder would fail erratically (digging divots in the filament).  I was also seeing a lot of filament shavings, and now I am seeing none.  My point is that having the idler very tight may not be universally good.

2 - Very interesting. Thank you.

3 - I have unscewed the end part of the extruder and there was some black burned material in it. There was no way I could have cleaned it from outside. very dark and very stuck. (the question is how can that be after 2 days ...)

I have cleaned it using a needle and acetone and the good news is that it work again !!! Cool !

BTW, even if prints are pretty good, I have the feeling I have lost a little bit of precision, especially at the beginning. I believe I should relevel the Z axis as I have probably changed the extruder Z position unscrewig/screwing him.

Thank you to every one for your help.

2) On the solidoodle electronics board, there should be 4 stepper motor boards. You will know what they are because they are four boards that plug into the main electronics board.  One of them should be next to a connector of wires that say "E" and which go to the extruder motor.  Take a voltmeter and measure the voltage with the red probe on the metal potentiometer of the board, and the black probe to any ground you can find.
   If you do this, post what voltage you get. the voltage determine the current limit of your extruder motor. Your extruder motor could also be skipping not because things are clogged, but if it was set too weak. This is very unlikely, but at this point might be worth double checking. Once you post back this, I can try to find what the default voltage should be set to.

3) So you are saying, you cleaned with the very small drill bit, but this did not help? Today I had a clogged nozzle, and I cleaned with a wire, then I extruded 200mm of filament through, cleaned again, and then I extruded another 200mm. It seems to have fixed my situation. My nozzle was getting clogged because I had the bed *too* low. There is a sweet spot where it must be low in order to stick, but not too low (if it's too low, it jams.)

*General tip, when using wire. In my case I could only find .3" nichrome wire. It is not as strong as steel wire.  I had problems with the wire when inserting into the nozzle. The solution is to take pliers, and only allow <1mm of the wire to stick out. Feed this in. Then, adjust the pliers and move the next bit of wire. Do this for a little, and then the rest should slide up the nozzle. The short bit of wire allows for the wire to go in without buckling/bending.

. I have baught some 0.35 drill but nothing better for me. So now I have dismantle the nozle but i am stuck has I am not equiped at all and I do not have 2 bolts to unscrew the head from the tube.

. Next step : buy kapton tape (don't know where in Paris i can buy that), buy bolts, buy a torch and try to clean.

. The temp sensor was glued to the nozzle with some kind of glue. Do someone know what it is ?

. Answering my mail, the support just said "go to the wiki". Thank you but the forum is better for the moment ... and the case is not close for me until I can print again.

As I don't see myself doing the big cleaning thing with a torch (i am not equiped to manage that sort of things) I will contact the support. I still believe this probleme is linked to the problem i had to extrude at the very beginning (first video).

jean

Okay so if you used this with these you could feasibly drill out the clogs from the bottom and not have to take anything apart.  If the twist drill didn't work you'd at least need these drill bit extenders to be able to hold and turn the small drill bit.  #80 bit is .0135"  .35mm is .0137" so it should work perfectly. 

What do you think, any reason this is a bad idea?

If you end up trying this please post your results. That would save a bit of time if you get a clog.

What do you think, any reason this is a bad idea?

I hope i'll be able to do it without all the burning thing !

What is strange is that I had the problem straight out of the box and then 2 days later again. I don't remember if I have left the extruder at high temprature during the 2 days (that's possible) but that doesn't explain the problem occuring at the very beginning ...

Jean

depending on how serious the clog is this may fix it. (my machine has clogged about 8 times in the past month or so.

if this doesn't clear the clog you'll need to take the nozzle off the printer (again do this at "printing Temperature" -trying to do it cold leads to problems since the plastic is pretty firmly attached to both the nozzle and the barrel, -trying to separate them means trying to shear a 3/4mm rod of solid ABS. - this could be why so many people are breaking their barrels!)

once you have the nozzle off you can look at it from the top side down.

you'll probably see a large crusty mess of brittle burned heat denatured plastic. either burn with a torch, dissolve in acetone a mixture of both, drill or scrape out the bits of plastic.

then return the nozzle and keep printing.

on my machine when I had to do this I found quite a thick layer or plastic, and that the poking a wire through the tip was getting less and less effective...
so if you find clearing a clog with a wire is becoming ineffective it probably means that you need to strip and rebuild your hot end cleaning it properly, (or replace the nozzle).
I imagine that everyone will experience a giant clog eventually since clearing with wire really only pushes the bit that's too hard to extrude back into the nozzle to come back and cause a problem later.