Problems printing accurate size holes

Good evening!

I printed off some filament clips (http://www.thingiverse.com/thing:282242) and noticed that they all have smaller holes on the side that touches the heatbed. Infact, it looks like it’s causing the plastic to melt. From the side profile, you can see the plastic melted outward.

Do I need to change the heatbed temp? I’m using the default settings for Cura (eSun PLA) which is the filament I’m using.

The autolevelling seems to be working fine from what I can tell.

Infact everything I’ve printed with holes, the side touching the heatbed has a smaller hole than the top side.

The default in Cura is for the first layer to be 125% of normal width, and 2-3x the normal thickness. This helps with bed adhesion. You can adjust this in expert settings under the advanced tab. Look for the “Quality” heading – you can adjust initial layer thickness and width there.

Thank you very much. That’s making a huge difference already!

Huge improvement!

The hole is still a faction smaller on the bottom, but not nearly as bad.
IMG_0194.jpg

Cool – glad it was helpful. :wink:

It’s likely the bottom will be a little different simply because it is pressed to the bed so there is almost a right angle where the plastic goes from horizontal to vertical. For the top layers, the filament will be naturally more rounded creating a sort of fillet at the edge where it goes from horiz. to vertical. You can adjust for this in pieces you make yourself by slightly filleting the edges that touch the buildplate, but doing that directly to an STL file is beyond my software so I don’t have any suggestions on that. The other option is to figure you’re just going to have to ream the holes and make them fit standard drill bit diameters.

I use one of these things to clearance holes as needed. http://www.ebay.com/itm/New-Expanding-Hole-Saw-Opener-0-14mm-Reamer-Installation-Steel-Kit-for-RC-Car-/121645287675?hash=item1c529fc8fb:g:4asAAOSwEeFVTFPF

I actually have one of those for making holes in the plastic bodies of my RC cars. :smiley: