3D printed NC: what did I do wrong?

The Rocketry Forum

Help Support The Rocketry Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.


Absent Minded Professor
Aug 22, 2015
Reaction score
I thought that the Pringles can rocket that is available on thingiverse might be a nice beginner 3D printing project. So I went to my University's free maker space and imported the file into Cura. I set the slices to 0.3 mm thickness and printed in PLA on a Prusa i3.

This is what happened. The cone looks pretty good until the tip. Does anyone know what went wrong?

ImageUploadedByRocketry Forum1489514627.491705.jpg

Here is the link to the thingiverse files: https://www.thingiverse.com/thing:887300
Sometimes you have to adjust speed settings so layers have time to cool, I had problems with the tips on some nosecones prior to setting a minimum layer time.
It might be a different problem on yours as mine normally just deformed due to excess heat whereas yours seems to have separated out.
Check fan speed too. Might be the area is too small, and the fan is cooling it all as its trying to extrude..

Although my issues are usually the bottom lifting off the print bed..
Another trick for getting better cooling is to print more than one of the object. The time it takes to go print the other one gives the first one time to cool.

Note with Cura, there's a minimum print speed, I think it's in the machine settings. It won't go below that speed, even if the cooling settings seem to require it. That tripped someone up on the lulzbot forums a while back. With PLA, it's probably already running max fan, but double check that as well.
I worked at a co. that made 3D printers, know a little about it. First of all the unit is less than $400 and made in china.

Too cheap, and source is not the best. We got stepper motors from them with lead screws on them. Cheap, that's about it.
They seemed often to pick rods that were BEND AND TWISTED before cutting the threads. It had to lift the platform, and would bind. The fun part is it cost more to ship them back than what they cost, so boss just threw them in a box in the corner. Thanks, globalization.

The fan is used to cool the extruder, not the part. The temp setting can affect how the strand feeds and lays up.

But the rest of your cone looks good, so the settings are not far off.

Looks like you have voids at the top, that means the extruder was temporarily clogged, or the feed mechanism bound up, strand not coming out, more probable.

Your resolution is: XY axis positioning accuracy 0.012mm
Z axis positioning accuracy 0.0025mm

so you cannot blame that. I suggest a better printer, and people who know how to set it and maintain it.