Fan Shroud too big?

[teoman]

Could it be that i have a slight calibration issue?

The fan shroud that i printed seems to be just a little bit too big. I would say about 2 mm or so. The fan just pops in, it is not a snug fit, and while trying to assemble it to the hot end, it seems like it may also be a couple of mm to tall.

It also seems to me that it is bending the hotend supports to the sides, they still fit, but i feel some stress on the nuts and bolts.

Any ideas?

[RegB]

If that picture is shown with the two bolts for the aluminum spacers fully tightened the shroud is WAY taller than the aluminum spacers, then yes, it is definitely TOO tall.

I would take it out, pre-heat the bed and extruder, check the scripts VERY CAREFULLY, then do a complete calibration.
See my thread at; http://forum.seemecnc.com/viewtopic.php?f=37&t=5930

That missing minus sign was SO easy to miss the first time around.

BTW, another thing with mine was that the Onyx screws loosened up after a few prints.
I know the manual says something like slightly more than finger tight, but one person's "slightly" may be another person's "barely" (-:
Anyway, as a firm believer in thermal expansion, I tightened mine up a "tad" more while everything was up to operating temperature.

[teoman]

I did the calibration twice.

Script 1
G28
G0 Z0 X0 Y90 F3500

Script2
G28
G0 Z0 X77.94 Y-45 F3500

Script 3
G28
G0 Z0 X-77.94 Y-45 F3500

So they seem to be good.

[teoman]

The nuts were not done up, but i was holding it tight. I saw no reason to do the nuts as clearly it would not have fit together.

[emile1138]

Yikes! That doesn't look right...

The fan should be a pretty snug fit in the shroud. Usually I have to really jam those suckers in there.
That being said, I'd say double check your scaling in your slicer software, if you're using it. Too tall+too snug+too wide=scaled too large I would think.

[teoman]

Not snug at all. There is a 1 mm gap between the side of the fan.

I am reprinting the part using mattercontrol. From the looks of it, size should be normal. I am noticin a lot more stringing though.

[Mac The Knife]

The spare fan shroud I have measures 24.95 mm tall

[teoman]

The new print turned out to be exactly the same size

[teoman]

I printed a calibration cube. 1.5mm.

It seems that the X and Y dimensions are OK. (I will get to my caliper today and do more precise measurements) It will do for a fan shroud. However the Z height of the cube is 1.65mm. About %10 too tall. :@

[guanu]

If you want to eliminate a possible slicing issue, print https://github.com/seemecnc/Orion_Delta ... DE/FAN.GCO
This is tested and working gcode for the fan shroud, if that file comes out too big as well, it would prove that its either a mechanical or firmware (such as steps per mm) issue. If it prints the proper size, this will tell you theres something up with either the model or your slicing settings.. give it a shot and post a pic of that with your previous one side by side to see how they look...

Guanu

[RegB]

If you want to eliminate a possible slicing issue, print https://github.com/seemecnc/Orion_Delta ... DE/FAN.GCO
This is tested and working gcode for the fan shroud, if that file comes out too big as well, it would prove that its either a mechanical or firmware (such as steps per mm) issue. If it prints the proper size, this will tell you theres something up with either the model or your slicing settings.. give it a shot and post a pic of that with your previous one side by side to see how they look...

Guanu

Not to beat up on the manual, but I think it would be a good idea to have it suggest that new builders use THAT FILE for their first print, thereby eliminating any slicer software issues.
Just get slicer variables out of the equations until the rest of the build is verified.

[teoman]

Had time to do a 3cm calibration cube. This one was recommened on the other thread.

X : 31mm
Y: 31mm
Z: 34.3mm

I will implement the G-Code when i get home.


What parameters should I be weary of in order not to destroy the PEEK component of the hotend.

[Mac The Knife]

Keep the extruder temperature below 240 C.

[teoman]

thanks, just made it back home and I have fired up the GCODE.


And so far, the semi intrusive calipering indicates that the part indeed is smaller.

So far %10 complete...

This is some funky G-code.

21% complete.

I can hear some pops coming, almost as if some wires were touching and creating a little spark. (I probably do not have the best filament in the world). ABS.

Print failed Part got detached.


Unfortunately the part was coming out to be the same size...

[teoman]

Redoing everythign now...

Erased the EEPROM and reloaded repetier 91.

I am running on a mac btw.

I noticed that before I had entered radius instead of diamater so corrected that...

Do I need to edit the X min and X Max?

[teoman]

Redoing everything now.

Z height was 336.98
now it is 389.385

[teoman]

I used artexmg's method for calibrating and i feel that it was not only easier but also more accurate.

--

Part started printing fine. Finest print i have ever printed. But at %96 the part got detached.

But the dimensions were accurate and the fan fit in snugly.

Trying it again. This time slower.