3D Printing Forum

Neotko...

Did you still need me to run those tests? I finally have some time off to do them

Lepaul. Could you run this tests?

- Install a firmware without the Fankickstart. This it's very important so the fans don't go 100% causing, probably, a too high power use. Use the default firmware if you prefer.

Ok. Now.

On the ulticontroller. Without printing anything.
a) Heat bed to 60 & nozzle to 75. No need to wait for the temp. Just set it.
b) While everything it's heating set fan speed to 10/255. Look at the fans if they do move, a lot, nothing or they start to tremble.
1. If they don't move raise from 10 to 20 and keep it going until they start to move. Also, if you see they 'tremble' take note of that number and keep going in increments of 10.
2. When you get to a number where both fans actually move. Write that down too. Now. Keep going up adding 10 to fan force until you get the heater error. Write that down.

Also..should i use the builder for the Experimental or Stable?

I used the Stable build

No fan kick start

Heated nozzle and bed as you asked...then, as you see in the video...manually changed the fan speed in the Ulticontroller in steps of 10

No error messages in this test.



Now after this, I loaded one of the small test print files. It printed the first layer then the second one, the fans kicked on and the error message halts the print.

A couple of comments on this...

These fans do not like either PWM or 19V...
There is almost no difference between 80 and 255, and even at 6/7 they are already fast.

The other thing is the Error, and it is most probably caused by the PWM noise on the line. That should be solved if you use the 'Slow PWM' option of the builder.

My recommendation would be -- in that exact order:

1. Build and install a 'Slow PWM' firmware, all other fan option set to default -- use the Experimental branch as we need one of the features there.

2. Test the firmware to see if you get error while printing. I yes, don't go further, we first need to solve that.

3. Find the lowest value your fans are still running once started. It is important as your fans are going hard at low PWM, we want to use the full range.
So you go to let's say 10 to get them running -- you might expect different values from your tests in the video, since 'Slow PWM' is now enabled -- and then go down one by one until they stop.
If they are still running with '1', then go to 4a, otherwhise do 4b

4a. Re-build a firmware with 'Slow PWM' and kickstart (300ms should be enough)
go to 5

4b. Re-build a firmware with 'Slow PWM', kickstart and 'Fan Minimum PWM' set to the lowest value your fans were running.
It will probably be '5' -- This is currently the lowest granularity in the builder (I could increase granularity)
For kickstart 300ms should be enough
go to 5

5. Make a test, your fans should start now at 1 and continue to spin
If they don't start, go back to 4 and increase kickstart delay
If they start but stop after a while, goto 4b and increase 'Fan Minimum PWM'

6. In Cura (Advanced properties in Cura Legacy), set the Max Fan to reflect the maximum speed we want. I might be different with the 'slow PWM', but based on the video, it does not look to me that we get much more flow beyond 80, so I would set the Max in Cura to about 30%)

That way we should be able to use the best range for your fans.

Very thorough response that I really appreciate

I'll do some testing and record!

Okay did Step 2

New Firmware with Slow PWM

Cura fan settings are as follows
Expected to hear fans come on....did not

I decided to continue to print without fans (to see how the new pulley is working to combat the Y axis leaning prints)

Print result (note left side artifact)
Better view. Not sure if that's an nGen setting or what. But nice to see it's an OK print despite fans not being on.

(Left side view shows artifact on both ends)

More results...

3. Find the lowest value your fans are still running once started. It is important as your fans are going hard at low PWM, we want to use the full range.
So you go to let's say 10 to get them running -- you might expect different values from your tests in the video, since 'Slow PWM' is now enabled -- and then go down one by one until they stop.
If they are still running with '1', then go to 4a, otherwhise do 4b

Printer fan engage/disengage test. Print head and bed not running temps

Slowly going from 0 to 32 very audible noise/buzz (not terrible)

Right side fan starts turning when fan speed set to 34
Left side fan at 36

Slowly changed settings to see when fans shut off.

Both fans stop at Fan Speed 0

Can you hear the high pitched sound?

Trying to do as much as I can late tonight so you will see it in the morning (your time)

6. In Cura (Advanced properties in Cura Legacy), set the Max Fan to reflect the maximum speed we want. I might be different with the 'slow PWM', but based on the video, it does not look to me that we get much more flow beyond 80, so I would set the Max in Cura to about 30%)

Fans now start at fan speed 1 (per step 5)

Fan speed 10 puts out some low airflow.

Fan speed 25 seems to be about what the old fan output

50 on up seems quite a bit...these guys move a lot of air

Based on that I am setting the following but not sure 50 fan speed = fan % in Cura?

I'm about to put this printer in the trash. More leaning prints

LePaul wrote: (Left side view shows artifact on both ends)

Probably the z-scar...

LePaul wrote: Based on that I am setting the following but not sure 50 fan speed = fan % in Cura?

Should be 50/255 * 100
But that would be quite low -- I would go for the 30%

LePaul wrote:I'm about to put this printer in the trash. More leaning prints

Mmmmmh...

Although this is a common problem, it never happened to me. Double check that your axes are still square (as something might have slipped since last time) and ensure that all pulley screws are tight (not only on the short belts).
The screwdriver provided with the printer is small and it is not easy to apply enough torque on the set screws; I always use a bigger one (I appreciate metric tools is are not easy to get in the US, but a good 2.0 mm hex wrench will help...)

Thanks for more feedback

I think 30 is plenty high given the power of the fans. I'm trying to sort out the math. What values should I put in the Cura and fan speeds?

The axis squaring is pretty impossible given when things seem square you can't reach the set screws i seem stuck in a loop of unresolved issues on this machine with so much to print. Frustrating!

LePaul wrote:I think 30 is plenty high given the power of the fans. I'm trying to sort out the math. What values should I put in the Cura and fan speeds?

Cura uses percentages, so if you set the max to 30% it will be 30% of 255 which is 76 on the Ulticontroller.

LePaul wrote: The axis squaring is pretty impossible given when things seem square you can't reach the set screws

There are enough notches on the gauge to have at least one where the set screws are well placed. The trick is to have the set screws (more or less) at the same place on both sides when you initially put the belt around them...

Ah so I need to sort out the algebra so fan speed 30 gives me a proper percentage to enter