Hi all got my ultimaker 2 go in jan 2016 and couldn't print at first, searched the net and did everything twice then changed the filament again and hey presto it printed, perfectly.
Several of my own prints down the line all was going well until I did a longer (time wise) print and three quarters of the way through it all went wrong. Under-extrusion... but why? Well I did all the checks it wasn't blocked etc etc etc. Then I noticed that most of the images I had found showed the knurled wheel with the grub screw pointing outwards. I noted a post that said an improvement had been the small gap in the black plastic cover to enable easy grub screw tightening. Mine didn't have an accessible grub screw - see pic was my wheel on back-to front?
I talked with the supplier who got ultimaker to send out a new wheel... this was longer than the original wheel.
I replaced the wheel, tightened and attempted to print... the filament was chewed even though I've never changed the tension settings ever and both wheels are the same diam. This happened a few times.
Next I tried pushing the knurled wheel a little further in along the shaft and tightened it and result, it printed fully. I decided to do test print two, it looked like all was going well and then suddenly it stopped printing properly and the print became patchy like always. A quick look at the back showed the wheel has slid out of place again.
Repositioned wheel, re-tightened screw and tried again... same thing, started well then stopped as the wheel came out again.
A search around the web tells me that some machines have the wheels facing a different way and if this is so, how the heck do I tighten that with ease??
Not sure what to do now but I'm real sure the problems are down to the wheel and nothing else... it's as if a good print is based entirely on chance.
Any help, advice, suggestions, name of ultimaker person to give a piece of my mind to (lol) greatly accepted.
Thanks.