UMO reasonable print speeds?

[aviphysics 9]

I am sure this is discussed here and there, but was hoping someone might be willing to walk me through it.

The main question is, what print speeds are reasonably achievable with a UMO. I figure there are two main limitations. The first is how fast the printer can extrude, and the second is how fast it can move the print head around. I think my main limitation is extrusion rate. I have read people talking about getting up to 5 cmm/s and I am just not able to get there at this point.

This is where I am currently at...

0) Filament is monoprice 3 mm white PLA ( I feel like that 3 mm might be part of what is slowing me down. )

1) Printer makes relatively defect free prints at 50 mm/s at layer heights from 0.05 mm to 0.2 mm (though I haven't tried going thicker or thinner). Going much faster than that, I start to get under extrusion. At 100 mm/s, I get under extrusion regardless of hot end temperature.

2) Printing at 50 mm/s and 0.15 mm layer height seems to require a hot end temperature of at least 195 C.

3) printer can run travel moves at 200 mm/s with acceleration set to 3000, without missing any steps.

4) Picture below is to show how much my feeder is digging in to the filament. I set it just high enough that the filament will rotate the gears without slipping, if I pull the filament out with the printer off.

 

[gr5 1,968]

You should increase the tensions on the feeder spring a bit I think. I would expect the teeth markes to be a little deeper.

You should be able to achieve similar print speeds to the UM2 which is about 10mm^3/sec at 230C so at .1 mm layers that would be 250mm/sec. That's kind of the top end. More data in the form of pictures and text here (post #2) which was done before UM2 existed:

http://umforum.ultimaker.com/index.php?/topic/1872-some-calibration-photographs/?p=13194

 

[aviphysics 9]

I have read that previously (just after I got the printer.) It was helpful, but it doesn't really cover feeder adjustments.

Do you have any pics if what the filament should look like if the feeder spring is set correctly?

 

[gr5 1,968]

 

[gr5 1,968]

The one on the left is not enough. The one on the right looks maybe a little too tight.

 

[gr5 1,968]

The next picture in my gallery is one I took. Just about right. The pink filaments photos were taken I believe by Simon/Illuminarti.

 

[aviphysics 9]

Ok. Tried to get results closer to the pictures mentioned. This filament must be way harder than the UM supplied stuff, because I had to put a nut behind the washer to get enough compression. It also occurs to me that this filament might just not be very good for 3D printing, at least not at high speed.

Currently testing.

 

[gr5 1,968]

Did you measure the filament? Is it actually 3mm diameter? Or 2.9? 3mm filament is not supposed to actually be 3mm. That is the absolute upper limit. Typically it is 2.85 or 2.9mm. Not 3.0mm. If it reaches 3.01mm it will probably clog in the bowden.

 

[aviphysics 9]

It is definitely 3 mm. I have since ordered 2.85 mm from Gizmo Dorks, but I have been trying to finish this spool first. The thought of just throwing it out has repeatedly crossed my mind, but the final prints from it seem to come out perfectly fine, as long as I don't go too fast.

 

[Stavros 1]

much obliged