HIPS printing improvements

Filament
1

Hi all,

I just replaced some cracked printed parts on my Mini and added the damper to the Y axis and replaced the PEI sheet. I figured this would be a good time to re-hone my filaments to make sure I’m getting idea prints.

I’ve been able to get it close, but it seems like the first few layers aren’t quite perfect. Please see the attached progression.

IMG_5210.JPG
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IMG_5211.JPG
IMG_5211.JPG1632×1224 321 KB

The part on the far right is where I am now. The initial layer thickness is perfect. Calipers are measuring 0.43-ish, the 20x20 block is coming in at about 20.1x20.1 which is pretty darn close. However, it seems like the first few layers don’t match the rest of the print. It appears the corners bow up a bit.

My guess is this is a cooling fan issue. Currently it’s set to the Lulzbot HIPS recommended 50% in their profile. Does this corner curve indicate I need to turn cooling down a bit?

Thanks
Jim

2

I had what looked like similar issues when trying to print the 3DBenchy. I lowered the bed temp 10-degrees to 100 and (along with increasing the filament diameter to 3.00mm (using eSUN HIPS)) that seemed to help. This is all from memory so you get what you pay for…
To your question, I think the cooling doesn’t kick in until the 5mm height or so, so maybe check that as well. I’ve found that since purchasing my Mini, experimentation is the best teacher.

3

Just checked Cura, the defaul HIPS profile has the fan kick on full at 0.5mm. Might be causing my corners to lift due to cooling. I’ll mess with increasing that height and see if I notice a difference. If nothing there, i’ll try lowering the bed temperature a bit.

Thanks!
Jim