UMO with dual fan shroud prints

[LePaul 321]

Hi

I have installed the upgraded dual fan shroud that Neotko designed and after refining the firmware some, have done a large test print. I am using 50mm fans.

I suspect that my 50mm fans which are rated for 14.13 CFM are extremely powerful and require me to really tune them down to much lower speeds.  That's where I am trying to fine tune.

I also just replaced the teflon piece

Here's my large print, where I printed at 0.2 layers and 210C    I had the fans running on what I thought would be an equivalent to 100% of the original ones.  (Again, we're experimenting)

I decided to up the temp to 212 a little ways into it since I noticed the infill look hairy.  

As I kept checking in, I noticed the print head temp was moving from 210 to 214 a lot, so I reduced the fan speed a bit ever few minutes to see if it could stay more stable.  

Here's the result...thoughts?  Keep bringing the fan speeds down more?

Edited July 15, 2016 by Guest

[neotko 1,417]

Print the @ultiarjan temp test

https://www.youmagine.com/designs/quick-temperature-fillament-test

I don't know if the gcode will work. But you can just print each area and increase manually the temp to see the differences. Also try to do the test with at least +5C increments.

[LePaul 321]

Should i focus more on raising the temps or lowering the fans further?

[ultiarjan 1,223]

Just slice it for UMO and manually enter the temperature lines in the gcode is easier imho.

[neotko 1,417]

Should i focus more on raising the temps or lowering the fans further?

 

You could test both. Just edit the gcode and set the new fans&temp at the desired layer or do it manually.

[LePaul 321]

I found i was underextruding the first layer starting at 200, but 205 worked good to start

Fans are at 14%...which seems to feel about as forceful as the single fan was way back when

Now to increase the temps manually as we go!

[LePaul 321]

I'm curious if this temp variation is of any concern? Leave alone? Too much fan?

 

[LePaul 321]

From bottom 205, 210, 215, 220, 225

40 mm/sec

Fan at 14%

[LePaul 321]

Any thoughts on how to improve the print quality?

@gr5 ?

[gr5 2,173]

.1mm layer 25mm/sec fan at 100% at 1mm nozzle temp 195C

Also if after that you still have all that ringing next to those round bumps then lower your acceleration to 2000 mm/sec/sec or instead maybe tighten the belts a bit more. Tightening or loosening the belts will change the harmonic frequency and reduce that ringing. Loosen them too much though and you get play. Lowering acceleration to 2000mm/sec/sec should reduce the jerk which will reduce the ringing also.

[LePaul 321]

100% fan and the printer will hover like a helicopter

The acceleration settings....in Cura or Ulticontroller?

Here's a test print of the Ultimaker Robot (210C, 40 mm/sec, 0.2 layers) Fans at 10%

I'll leave the temp alone and try lowering fans to 8% and then at 12%. More prints coming

[LePaul 321]

Okay

From left to right...

Fan at 12% , 10% and 8%

[LePaul 321]

Last night's overnight print...

[gr5 2,173]

Ha! You didn't follow my advice. :(

.1 layer, 25mm/sec, 100% fans by the time you are at layer 1mm from bed.

[LePaul 321]

@gr5 , I don't understand your advice...I can't run the fans that high...they are too powerful

Did you mean ringing?

Edited July 18, 2016 by Guest

[gr5 2,173]

Oh okay about the fans.  But definitely try .1mm layer height and 25mm/sec and lower your nozzle temp some more.

Edited July 18, 2016 by Guest

[LePaul 321]

The guys thought my brass pipe and heater block needed a gap...but in taking the head apart and comparing with a spare hot end kit, those thread into the heater block flush. No gap.

I can reduce the acceleration and do a robot at .1mm and 25mm sec. shortly

[neotko 1,417]

Old wiki explained very well how to know the correct amount of barrel to put inside the block.

[LePaul 321]

Yeah, as we noted on 3dprintingforum, my nozzle isn't sitting flush. I assume the block has to be hot to get that barrel to unscrew at all

[neotko 1,417]

If it's cold (and assuming you never got a leak inside the peek) when cold (or 90C) you can take out the peek if you unscrew it.

To take out nozzle or barrel you need to loose the nozzle while hot (at least 150C but since you got leaks inside the alublock probably 200C so you don't force much the screws of the alu block.

Edited July 18, 2016 by Guest

[gr5 2,173]

aluminum and brass is soft - many people have destroyed their brass parts using a simple hand wrench. Go easy! use heat! Use WD40 (works even better than liquid wrench).

[LePaul 321]

Good tip (hey that's a pun!)