Solved Need to Disassemble Hot End and problems with z-height

Hey guys,

I just got my robo last week and it was working fine then BOOM problems. What appears to be happening is that it is printing so close to the bed that the filament stays jammed up in the extruder, eventually the hobbed bolt eats through the filament and I get a jam. The first few times I was able to pull the filament out through the top to clear it but this time no such luck. Could anyone provide me with pictures or help of where the screws are located to remove the hotend to attempt to clean it?

Also some advice on how to set the z-height would be great. I thought it was supposed to autocalibrate but after my first part printed flawlessly I have since had nonstop problems.

Thanks

 

can you find your z offset using mattercontrol? I never found the window that showed me where my axis was. Always used repetier-host to find my offset.

 

The hotend drops out when you remove these 2 screws.

 

Thanks so much mike for the photo! That is a huge help! Fortunately I was able to clear the jam without dissasembling. However, after extruding about 30 mm the hobbed bolt starts to chew threw the PLA again and I gotta pull it out and refeed or I get another jam. Any suggestions? I noticed another poster above mentioned seasoning? What does this mean and what would that process entail?

Thanks for the quick response and help everyone!

 

Also, I just tried a test print and it is still printing so close to the surface that it is barely leaving a visible line of filament, then eventually being chewed through by the bolt. Any ideas on this? And as little greek as possible lol. I have some technological know how but not always up to speed with the lingo.

 

ha yea...

USE VERY LITTLE OIL.

last time I used PLA on a fresh extruder I just used a papertowel and moistened a few feet of filament. Worked fine.

 

Is it barely visible because you're too close? That clogs heads... especially with pla. Pla can't force its way out like PET and Nylon. It just breaks apart.

If your nozzle is marred mechanically or jammed physically. Try the oil and a good cleaning (likely inside and out) You need to set your Z offset and/or your first layer thickness.

 

yes Defender, I beleive it is too close but first layer is set to .3 which was the stock setting. What would you recommend changing it to? Also, I used your advice from our personal convo and made sure that the z was in line on the x-axis. It seemed a little off visually so I centered the hot end on the plate and used the method until I heard the switch click on both sides. Still too close after this adjustment.

 

Man I wish I had chosen a different name...
anyway..
.3 is fine.. its super.. that's the easy height.
its the percentage of that that your first layer is set to.
Somewhere in whatever software you're using it will say something like "first layer height" and have a percentage of that .3mm. If you set that to 10%. well... easy math.. that's too low.

Your Z offset is different.
That's a whole different setting. The way I set it is.. I open repetier host (because its easy) using the jog controls, home the head then raise .01mm till its off the bed.. then down 1 or 2 clicks. Z offset is now your Z position listed in the top right.

 

or... set it in your settings
though with his way.. you'll see it do a little jog to know its done.
with mine.. you see it right before printing. almost all slicers have a place for this setting.
Either way. Just make sure you do one OR the other.

you're setting the distance between when the nozzle hits the bed and the switch clicks. when dealing with fractions of a mm this distance is critical and varies a few tenths.

It will be around 1mm.. .8-1.2 ish. It is set to 1mm by default. Yours is likely more towards 1.2

 

Hey guys I got it figured out. I had switched from matterslice to cura and that messed it all up. Once I switched back I was able to find the z-offset in the settings, also found in with the slic3r. Just not with cura for some reason. I am printing now, but for some reason am throwing off the x and having offset layers. Every few mm it throws off to the right. Belt tension seems ok. This was with matterslice, going to try with slicer and see if this makes any difference. Once again everyone thanks for all your help and sorry for the late reply back. School has been keeping me busy.

Also quality of the layers is looking pretty rough and shoddy. I will try to get some picks up later, but for now stopping the x from shifting is my main priority. Although I did successfully print a new top spool holder before the x started throwing off. so YAY!!

 

these things are ne'er the slicer's fault. I mean, different ones act a bit different. but they print in the right direction.

if you have x shifting you have physical problems.

 

yea... I have not run into that... i was hypothesizing the existence of such a thing. I can't imagine what would cause it to just cough out garbage.

I've had it come up with all kinds of stupids... but it always printed like the slice preview. Be it with extra triangles or missing them. Believe me, the first couple things I drew were full of crazy nonsense. I learned to delete things I didn't need.