# Advice asked: Small indentation at the bottom of my print
**URL:** https://discourse.shapr3d.com/t/advice-asked-small-indentation-at-the-bottom-of-my-print/41562
**Category:** 3D Printing
**Created:** [August 31, 2026, 1:21pm UTC](https://discourse.shapr3d.com/t/advice-asked-small-indentation-at-the-bottom-of-my-print/41562 "2026-08-31T13:21:52Z")
**Posts on this page:** 17
**Page:** 1
### Author:  [@margriet](https://discourse.shapr3d.com/u/margriet)
#### Post date: [August 31, 2026, 1:21pm UTC](https://discourse.shapr3d.com/t/advice-asked-small-indentation-at-the-bottom-of-my-print/41562/1 "2026-08-31T13:21:52Z")
Hi everybody!
I designed this model in Shapr3D on my iPad. In the model, the side walls are completely straight and smooth.
However, when I print it on my Bambu Lab A1 mini, I always get a small indentation where the bottom transitions into the vertical walls (see photo). I’ve tried several different print profiles, but the result is basically the same every time.
Has anyone seen this before or have any suggestions on what could be causing it? Is there something I could change in the design, or is this more likely a slicer/printing issue?
Thanks!
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### Author:  [@DrKronos](https://discourse.shapr3d.com/u/DrKronos)
#### Post date: [August 31, 2026, 1:42pm UTC](https://discourse.shapr3d.com/t/advice-asked-small-indentation-at-the-bottom-of-my-print/41562/2 "2026-08-31T13:42:19Z")
That is called a “hull line”. This happens when the layer that is full filled out (the bottom of you tray) contracts a bit more than the section where there’s only walls on cooling.
A very common problem in FDM printing, not always that easy to solve.
Here’s a few ideas on how to avoid it: [https://www.youtube.com/watch?v=ITighzYPTTs](https://www.youtube.com/watch?v=ITighzYPTTs)
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### Author:  [@margriet](https://discourse.shapr3d.com/u/margriet)
#### Post date: [August 31, 2026, 2:36pm UTC](https://discourse.shapr3d.com/t/advice-asked-small-indentation-at-the-bottom-of-my-print/41562/3 "2026-08-31T14:36:24Z")
Thanks, it was a long movie and the best tip was at the end. I have changed the design. Will try to print it again. I will let you know.
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### Author:  [@Fawksey3D](https://discourse.shapr3d.com/u/Fawksey3D)
#### Post date: [August 31, 2026, 9:38pm UTC](https://discourse.shapr3d.com/t/advice-asked-small-indentation-at-the-bottom-of-my-print/41562/4 "2026-08-31T21:38:52Z")
Nice design though. Like the splayed finger gap. Good job.
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### Author:  [@margriet](https://discourse.shapr3d.com/u/margriet)
#### Post date: [September 1, 2026, 2:49pm UTC](https://discourse.shapr3d.com/t/advice-asked-small-indentation-at-the-bottom-of-my-print/41562/5 "2026-09-01T14:49:54Z")
Hi Everybody,
I have made a second one. Used chamber and fillet at the bottom. I preferred the first one. Perhaps I should make the bottom much thinner and very little wider?
Which one do you prefer?
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### Author:  [@Fawksey3D](https://discourse.shapr3d.com/u/Fawksey3D)
#### Post date: [September 1, 2026, 3:24pm UTC](https://discourse.shapr3d.com/t/advice-asked-small-indentation-at-the-bottom-of-my-print/41562/6 "2026-09-01T15:24:11Z")
The smaller has nicer proportions to my eyes.
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### Author:  [@michelpiazzini](https://discourse.shapr3d.com/u/michelpiazzini)
#### Post date: [September 1, 2026, 3:50pm UTC](https://discourse.shapr3d.com/t/advice-asked-small-indentation-at-the-bottom-of-my-print/41562/7 "2026-09-01T15:50:42Z")
Good afternoon,
I mostly make a small recess at the bottom of the box. This reduces the tension around the bottom layers and the wall.
Off course I would also add a chamfer outside and a fillet inside the box
It makes a big difference and the ugly line disappears nearly completely.
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### Author:  [@margriet](https://discourse.shapr3d.com/u/margriet)
#### Post date: [September 1, 2026, 5:06pm UTC](https://discourse.shapr3d.com/t/advice-asked-small-indentation-at-the-bottom-of-my-print/41562/8 "2026-09-01T17:06:35Z")
Thank you, Michel. Great tips! I will try that. I did remove the fillet inside the box, because I was afraid, the businesscards wouldn’t fit. The recess, are that two stripes, or four, like a square?
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### Author:  [@margriet](https://discourse.shapr3d.com/u/margriet)
#### Post date: [September 1, 2026, 5:08pm UTC](https://discourse.shapr3d.com/t/advice-asked-small-indentation-at-the-bottom-of-my-print/41562/9 "2026-09-01T17:08:05Z")
“The smaller has nicer proportions to my eyes.”
I agree!
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### Author:  [@DrKronos](https://discourse.shapr3d.com/u/DrKronos)
#### Post date: [September 1, 2026, 5:09pm UTC](https://discourse.shapr3d.com/t/advice-asked-small-indentation-at-the-bottom-of-my-print/41562/10 "2026-09-01T17:09:04Z")
> [@margriet](#):
>
> erhaps I should make the bottom much thinner and very little wider?
Making the bottom thinner will also help avoid that hull line. If you bottom is thin enough that there isn’t any infill between the bottom and top (only fully filled layers), the bed adhesion on your print will make your fully filled layer contract less aggressively. And you won’t have a shift from infill height to top layer height.
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### Author:  [@margriet](https://discourse.shapr3d.com/u/margriet)
#### Post date: [September 1, 2026, 5:20pm UTC](https://discourse.shapr3d.com/t/advice-asked-small-indentation-at-the-bottom-of-my-print/41562/11 "2026-09-01T17:20:09Z")
Yes! I did already tried that this afternoon. I will also try the solution of Michel.
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### Author:  [@margriet](https://discourse.shapr3d.com/u/margriet)
#### Post date: [September 1, 2026, 5:31pm UTC](https://discourse.shapr3d.com/t/advice-asked-small-indentation-at-the-bottom-of-my-print/41562/12 "2026-09-01T17:31:23Z")
Another question: what if I dont use an infill but made the bottom fully filled layers, like you say with a thin bottom. Does that also work with a thicker bottom?
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### Author:  [@DrKronos](https://discourse.shapr3d.com/u/DrKronos)
#### Post date: [September 1, 2026, 5:47pm UTC](https://discourse.shapr3d.com/t/advice-asked-small-indentation-at-the-bottom-of-my-print/41562/13 "2026-09-01T17:47:19Z")
That depends how many fully filled layers you want to print. It quickly becomes a game of diminishing returns, as the contract forces will still make the full layers contract more than your container’s walls. The effect of the bed adhesion diminishes the higher you go.
You may also introduce another problem: warping. The more material you heap on, the more likely the piece will start to warp, to the point where it can bend itself off the plate.
PLA isn’t too problematic with this, it doesn’t warp a lot. With other filaments it’s something to keep an eye on, for example ABS is notorious for warping.
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### Author:  [@markse](https://discourse.shapr3d.com/u/markse)
#### Post date: [September 1, 2026, 8:44pm UTC](https://discourse.shapr3d.com/t/advice-asked-small-indentation-at-the-bottom-of-my-print/41562/14 "2026-09-01T20:44:20Z")
That looks good. At some point, you’ll have to accept that you’ve got it.
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### Author:  [@margriet](https://discourse.shapr3d.com/u/margriet)
#### Post date: [September 2, 2026, 4:00pm UTC](https://discourse.shapr3d.com/t/advice-asked-small-indentation-at-the-bottom-of-my-print/41562/15 "2026-09-02T16:00:49Z")
Thank you @michelpiazzini I made this model with your tips. Small lines in the bottom and a small fillet at the outside bottom. I am happy now. Thank you all so much. It was very helpful. I have placed it on
[https://makerworld.com/en/models/3252922-businesscardholder-90-x-50-mm#profileId-3686712](https://makerworld.com/en/models/3252922-businesscardholder-90-x-50-mm#profileId-3686712)
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### Author:  [@Oregonerd](https://discourse.shapr3d.com/u/Oregonerd)
#### Post date: [September 2, 2026, 4:49pm UTC](https://discourse.shapr3d.com/t/advice-asked-small-indentation-at-the-bottom-of-my-print/41562/16 "2026-09-02T16:49:59Z")
The other thing that would have possibly worked is to fillet the bottom inner edge, raise the center of the bottom and put vertical guides (2 per side).
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### Author:  [@margriet](https://discourse.shapr3d.com/u/margriet)
#### Post date: [September 2, 2026, 5:02pm UTC](https://discourse.shapr3d.com/t/advice-asked-small-indentation-at-the-bottom-of-my-print/41562/17 "2026-09-02T17:02:05Z")
I will that remember for my next design. Now the business cards fits!😍