Noob printing issues

[danilius 118]

I have just bought an ultimaker 2 (yay!)

Having read the visual guide at 3dverkstan.se and hunted around the web, I'm not sure what's causing these problems at the top of the teeth on this small rack. There are small overhangs on one side of the teeth. Any idea what's causing it?

I tried slowing down the print speed to 30mm/s but that did not really make a difference.

Another weird thing was that I also tried slowing down the acceleration speed to 1500 and not enough plastic was extruded to print anything, but that's not terribly important (unless of course it is!).

Anyway, I'm sure one of you can push me in the right direction.

Cheers!

 

[SandervG 1,518]

I think your pictures are labeled as private..

can you make them public so we can see them?

 

[danilius 118]

In my infinite genius I uploaded the images and somehow did not realise that they needed another step to complete the upload. They should be visible now. Thanks Sander!

 

[pm_dude 27]

I think this is a very small print. What is the size of the piece?

The overang you see around the teeth is most probably "frequent" retraction leaks. This happen when the head need to jump from one section to the other. You can play with the retraction settings and material temp to see if it will help.

Try scaling the piece up and see the difference.

 

[danilius 118]

Thanks for that, pm_dude. I cannot scale the piece up since that's the size the component has to be. It's roughly 22mm long, 7mm wide.

I'm such a noob that I'm not really sure what to try in this case - any suggestions?

 

[jameshs 42]

How big is the piece - looks small? - if it is small then it is several things - stringing, plus the fact that the nozzle is too hot and re-melting - difficult to avoid with a piece that small - I was asked to print a cog with similar teeth and it just melted them on each pass - just like that and that is the limitatation of the printer on weeney small pieces.

I would try printing it on its side as you won't have that problem. If that works then you could break the model in 2 and print and join (just sink it into the printbed by 50% of the height.) or use support - but I think support might be worse.

You could also try printing it upside down.

Or re-design so that the teeth have a flat top - often you don't have any contact on that top part - so more like a pinon.

James

 

[pm_dude 27]

I like the idea of printing it on the side but I don't see the need to split the model in half.

 

[visu-al 2]

Maybe just print multiple parts and on the side.. and slower with lower temp

 

[DidierKlein 729]

You probably need to slow down (20mm/s - 30mm/s) and put the lowest temperature possible (this depends on the filament brand and colour). Try to go as low as possible 200°c should be okay but you can go lower (190°c - 180°c).

If the top part seems to be melted then either print two at the same time or print a tower next to it so that it lets the layers cool down more.

 

[danilius 118]

This are superb suggestions. I'm going to have another whirl at it and if anything reasonable-looking comes out of it post the results here.

Cheers!