gixxer

Quick update. Been using the new IPM for some time now and haven't noticed any improvement. But I wasn't experiencing any real problems before. The new IPM is still in my machine being used every day.

Yes get the emails working again PLEASE. I haven't been back to this forum in a while for the same reason as Swordriff. I bet you've seen a huge decline in activity since the change to the new forum!

Been printing with polyflex all day today and an 18h print running now. There's reasonable retractions. So far it's working great. I'm using the first Teflon replacement. This polyflex has to be one of the best most printable flexible filaments I've used.

We use large quantities of liquid nitrogen at work now that would be a crazy idea! Access to compressed air is easy for me at work. If the regulator was outside and set to 0.5 bar it should be reasonably quiet. Question is, is it worth the effort?

Update on the ColorFabb XT-CF20 Had another go with the XT-CF20 only to see under extrusion once again. However this time I sat and watched in fail. The print was solid so very little retraction. I did manage to recover it by increasing the temp to 260C! (yes I know!) and reducing the fans down to 50%. The temp change didn't have any noticeable effect on the print though. The actual nozzle temp was at set point (250C) prior to under extrusion. Material - ColorFabb XT-CF20 Total Print time - 4h Max print per model - 7h Nozzle type - 0.5mm (E3D) Temp - 250C Speed - 50mm/s Retraction/No retraction - Yes Time to fail - 2.5h FIX for fail - Increase temp and lower fan speed.

Hi John, I sometimes get small inclusions of dark char like deposits within a white print. Whenever I've watched this happening it's source has been the outside of the nozzle and not from within. Check the nozzle surface is clean before starting a print. Any small pieces of filament that are stuck to the outside can release after its gone through a few heating and cooling cycles which then get embedded in the print. This is far more noticeable on a white print due to the contrast.

It might be worth mentioning that I print with a lot of ninja flex which I always oil pre feeder. Consequently there is almost always a small pool of oil around the Teflon isolator even when not using ninjaflex. Now I don't know the implications of this on clogs but I don't really get them. Could it be worth someone else trying to print with a material that that know they will have issues with and run a small amount of oil along the filament pre feeder?

I had a fail with ColorFabb XT-CF20 to but there was no retractions at the failure point at all. The print was a 10" tablet case layer flat that failed just before it got to the walls. I'm going to give the ColorFabb XT-CF20 another go soon on a more challenging print.

OK not an original idea. It's been discussed here https://ultimaker.com/en/community/view/4536-compressed-air-cooling-as-alternative-to-fans?page=2 But not concluded 8)

Crazy idea alert!! Just wondering, has anyone tried running a compressed air line to the head? It could be run next to the bowden and into almost any shaped duct without having to worry about flow. It could be controlled using a regulator and valve. The air would be much cooler than the hot air above the heated bed that the fans currently circulates. I would think you'd also have a significant weight reduction on the head.

Labern- You are absolutely right. The fans on the um2 are not designed to be restricted. If you look at the fan curves for this kind of fan you'll see than when restricted the air flow plummets. You need compressor/blower fans if you plan on restricting the flow.

Just found a gcode analyser http://gcode.ws/ I'll have to wait until tomorrow to try it out though.

Lol! Perhaps I'll tell the boss it's for his kids that normally works:P I'm using Roberts feeder also. The ninja flex semi flex is very good by the way.

Ive not ptinted anything as retraction heavy as http://www.thingiverse.com/thing:287891 as yet. If anything, in the past when attempting prints like the Elephant - Voronoi Style I would have problems with grinding the filament. Id like to add that I change filament materials several times a day and never do an atomic pull. I just use the move material option to clear out the last filament from the nozzle and thats only if I'm not using a skirt/brim. Is there any way of easily counting the retractions in the gcode? If so I'll happily let you know. Printing Elephants at work can only be done when the boss is off It might also be a good idea to state the retraction distance used. All my tests where done at 4.5mm @ 25mm/s. Perhaps a longer retraction would cause more problems.

Material - Ninjaflex Semiflex Total Print time - 8h Max print per model - 8h Nozzle type - 0.6mm (E3D) Temp - 255C Speed - 50mm/s Retraction/No retraction - Yes Time to fail - n/a FIX for fail - n/a Material - Taulman T-Glase Total Print time - 5h Max print per model - 5h Nozzle type - 0.5mm (E3D) Temp - 250C Speed - 40mm/s Retraction/No retraction - Yes Time to fail - n/a FIX for fail - n/a