mmcgraw74

Hi Monty, mmm, no, I have not noticed these "noises" ... perhaps the screw that adjusts the distance of the ball bearing was too tight and requires a greater effort from the feeder ? Guglielmo I did suspect the adjustment might be optimized for 1.75mm filament. So I'm currently running with the cap on the screw head not touching the "arm" and putting a small piece of filament between the arm and the block - seems to have eliminated the noises. I also printed a Robert version 2 feeder to replace the stock feeder.

Guglielmo, Thanks for your great UM2 upgrade idea, and thanks to Tinkergnome for his great UM2 firmware update. I just installed my Tunell Filament Monitor on my UM2 as you described, but I had unusual noises in my feeder and noticed fairly high tension on the connection from the output of the filament monitor to the feeder. I moved my filament monitor closer to the feeder as my photo shows, using a longer bolt to attach to the left servo cover - now the feeder noise is gone. Thanks, Monty I also updated the monitor timeout to 16 seconds. I'll bet the 8 second default timeout is fine for the 1.75mm printers or filament, but not the 2.85mm we use. Monty

Guglielmo, Thanks for your great UM2 upgrade idea, and thanks to Tinkergnome for his great UM2 firmware update. I just installed my Tunell Filament Monitor on my UM2 as you described, but I had unusual noises in my feeder and noticed fairly high tension on the connection from the output of the filament monitor to the feeder. I moved my filament monitor closer to the feeder as my photo shows, using a longer bolt to attach to the left servo cover - now the feeder noise is gone. Thanks, Monty

Hopefully the final update on my z-axis problems. My dropped layer issue returned after a couple of days. I contacted support again - they sent a replacement lead screw with attached servo. As I disassembled the leadscrew, I also removed the two vertical shafts and noticed oil on those shafts again. It appears when I put oil on those shafts some of it made its way down to the hole in the base and removing the shaft put more oil on it :( I tried to remove oil from the hole, sprayed both vertical shafts with brake cleaner spray (which really removes all the oil and any grease) and reassembled. In performing the vertical bearing alignment - I decided to try raising the buildplate to about half way up the vertical shafts and performing the alignment there instead of at the bottom of the printer. My theory was the shafts may be slightly further apart at the top of the printer, so trying the alignment in the middle might help. After tightening the bolts on the bearings I raised the bed and lowered it manually and found it was much easier to move the bed up and down at the top of the printer - and it was a little more difficult to push the bed to the bottom of the printer manually. I've been printing for a week and my z-axis issues have not returned. Here is an example of printing four ABS models yesterday - about 4 inches tall. Monty

I put in my replacement bearings - much smoother action on the vertical shafts. I also took the opportunity to carefully clean the z-axis screw with a paper towel, turning the screw with my other hand. There are a couple of different tracks to clean. Then I regreased the z-axis screw with the package of grease that was included with the printer. I've been printing for a couple of days without the missing layer issue - fingers crossed Monty

I'm having a very similar issue on my Ultimaker 2 that I purchased this month. I have a support ticket open - I even pulled the vertical bars and linear bearings off mine last night. I could easily pull the bearing up the bar, but it would 'hang' going down if I pulled the bearing near the top of the bar. Same thing for the second bearing and bar. I swapped the bars end for end and swapped the bearings between bars - same symptom. I put the printer back together (following the installation guide I found on github) and thought it might be a little better - but tried printing a 2 inch tall cylinder with walls about 0.2" thick and once again heard the "thunk" as the buildplate dropped - causing that layer to not stick to the previous layer. Since I was printing layers at 0.15mm thickness, a couple of layers later the filament began to stick - but this error results in the part having no strength at the bad layers. Here is my photo of the bad cylinder on the left. The other two parts are shorter and were fine. scaddesign - did you get your issue resolved? Monty

I'm interested in buying your UM2 printer! Monty