<p>The basic concept is that one part is attached to a base and the other part attached to the other part (this can have a base as well on the plate, but this is not the case in the example). The idea is that by allowing the printer to print over a gap (so basically bridging) the parts are printed separately or with a minimum of adhering to each other.</p>
<p>When taking a cross section, this looks like the following:</p>
<p><a href="https://i.sstatic.net/kQpZ04b8.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/kQpZ04b8.png" alt="Cross section of a hinged print-in-place object" /></a></p>
<p>It is up to you to instruct the slicer how to print the (bridging) layers over the different parts.</p>
<p>The slicer isn't specified, in the queestion, therefore, this answer provides a solution based on Ultimaker Cura. This slicer has experimental settings how to treat the bridge layer:</p>
<p><a href="https://i.sstatic.net/LhY1qE4d.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/LhY1qE4d.png" alt="Snapshot of the Experimental settings in Cura" /></a></p>
<p>Note that you can now control the amount of cooling you want for the bridging layers (up to 3). If we look at the generated G-code with this option enabled, the bridging layer is printed at a low speed. Combined with the extra cooling, you can solidify the deposited filament before it has time to stick to the already printed structure:</p>
<p><a href="https://i.sstatic.net/U4RuRAED.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/U4RuRAED.png" alt="Slice with &quot;Enable Bridge Settings&quot;" /></a></p>
<p>Without this option enabled, the speed would be unaffected and the filament would not have time to solidify:</p>
<p><a href="https://i.sstatic.net/IxxCUyAW.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/IxxCUyAW.png" alt="Slice without &quot;Enable Bridge Settings&quot;" /></a></p>

CC BY-SA 4.0
2024-08-04T18:28:17.393Z
Thank you for the detailed answer! I was not aware that bridging could create such complex structures or about the technique to cool the filament before it can attach to lower layers.
louis
CC BY-SA 4.0
2024-08-04T18:29:47.540Z
One follow up question... do you know why there is not a continuous outer blue perimeter on the hinge piece in your photo? AKA, why the speed increases when the perimeter is not straight lines? I imagine bridging might not be possible here, but if that is the case, is there anything stopping these curved parts of the perimeter that aren't treated like bridges from attaching themselves to the base?
louis
CC BY-SA 4.0
2024-08-04T18:45:06.900Z
I added two photos to my original question at the bottom. It shows how the hinge is attached to the oblong base in the bottom right hand corner. So the bridge becomes the perimeter of the complex hinge shape, which seems much more complex than a straight-line bridge with two bases/foundations, one at each side. In this case, it seems like the bridge would be made, dry in mid-air using the technique you described, but then sag down ~1mm to rest on the base below. I imagine that would mess up the rest of the print around this hinge since it essentially increases the Z-offset of each layer by 1mm
louis
CC BY-SA 4.0
2024-08-04T18:46:28.950Z
(I know that isn't actually what happens, I'm just trying to understand why so I can use this technique in my own designs)... thank you again!
louis
CC BY-SA 4.0
2024-08-03T12:05:59.997Z
2024-08-04T19:29:35.923Z
2024-08-04T19:29:35.923Z
0scar
<p>I've been looking into print-in-place models, and am having trouble understanding how some pieces are printed, they look almost like they are printed out of thin air.</p>
<p>One example is the <a href="https://www.printables.com/model/299532-chip-clip" rel="nofollow noreferrer">Kaiser clip</a>. As shown at <a href="https://youtu.be/qcDRJvX-qbQ?si=72zFIC2t-6lswJ7r&amp;t=125" rel="nofollow noreferrer">minute 2:05 in this 3D Printing Nerd YouTube video</a>, there are two hinges that rotate around pins. These pins are attached to a base, however, the hinges are not (which allows them to rotate). I do not understand how these two hinges could be printed without also being attached to that base.</p>
<p>When I slice it, it wants to add bridges in the 4 mm gap between the base and hinge. I can't understand how the print would be successful without these bridge infills, but I also imagine these bridge infills will stop the hinge from working.</p>
<p>To say it another way, in my mind, when the hinge begins printing around the pin, it must have some clearance from the base and pin itself so that it doesn't adhere to them. I don't understand how this is possible without creating supports within these moving mechanisms.</p>
<p>How are prints like these meant to be printed?</p>
<p><a href="https://i.sstatic.net/FyvIbz5V.png" rel="nofollow noreferrer" title="Screenshot of PrusaSlicer's Preview of the Kaiser clip model"><img src="https://i.sstatic.net/FyvIbz5V.png" alt="Screenshot of PrusaSlicer's Preview of the Kaiser clip model" title="Screenshot of PrusaSlicer's Preview of the Kaiser clip model" /></a></p>
<p>TWO NEW PHOTOS for my comment below.</p>
<p><a href="https://i.sstatic.net/JpJ4Hzj2.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/JpJ4Hzj2.png" alt="Layer before bridging" /></a>
<a href="https://i.sstatic.net/FyPEYQNV.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/FyPEYQNV.png" alt="First layer of bridging" /></a></p>

<print-quality>
How should this print-in-place hinge be printed?
louis
# How should this print-in-place hinge be printed?

(Asked by: username_0 on 2024-08-02)

I've been looking into print-in-place models, and am having trouble understanding how some pieces are printed, they look almost like they are printed out of thin air.

One example is the [Kaiser clip](https://www.printables.com/model/299532-chip-clip). As shown at [minute 2:05 in this 3D Printing Nerd YouTube video](https://youtu.be/qcDRJvX-qbQ?si=72zFIC2t-6lswJ7r&t=125), there are two hinges that rotate around pins. These pins are attached to a base, however, the hinges are not (which allows them to rotate). I do not understand how these two hinges could be printed without also being attached to that base.

When I slice it, it wants to add bridges in the 4 mm gap between the base and hinge. I can't understand how the print would be successful without these bridge infills, but I also imagine these bridge infills will stop the hinge from working.

To say it another way, in my mind, when the hinge begins printing around the pin, it must have some clearance from the base and pin itself so that it doesn't adhere to them. I don't understand how this is possible without creating supports within these moving mechanisms.

How are prints like these meant to be printed?

[![Screenshot of PrusaSlicer's Preview of the Kaiser clip model](https://i.sstatic.net/FyvIbz5V.png "Screenshot of PrusaSlicer's Preview of the Kaiser clip model")](https://i.sstatic.net/FyvIbz5V.png "Screenshot of PrusaSlicer's Preview of the Kaiser clip model")

TWO NEW PHOTOS for my comment below.

[![Layer before bridging](https://i.sstatic.net/JpJ4Hzj2.png)](https://i.sstatic.net/JpJ4Hzj2.png)
[![First layer of bridging](https://i.sstatic.net/FyPEYQNV.png)](https://i.sstatic.net/FyPEYQNV.png)

**Tags:** print-quality


---

## 1 answers

### Answer by username_1 on 2024-08-03. Score: 0 | Accepted answer

The basic concept is that one part is attached to a base and the other part attached to the other part (this can have a base as well on the plate, but this is not the case in the example). The idea is that by allowing the printer to print over a gap (so basically bridging) the parts are printed separately or with a minimum of adhering to each other.

When taking a cross section, this looks like the following:

[![Cross section of a hinged print-in-place object](https://i.sstatic.net/kQpZ04b8.png)](https://i.sstatic.net/kQpZ04b8.png)

It is up to you to instruct the slicer how to print the (bridging) layers over the different parts.

The slicer isn't specified, in the queestion, therefore, this answer provides a solution based on Ultimaker Cura. This slicer has experimental settings how to treat the bridge layer:

[![Snapshot of the Experimental settings in Cura](https://i.sstatic.net/LhY1qE4d.png)](https://i.sstatic.net/LhY1qE4d.png)

Note that you can now control the amount of cooling you want for the bridging layers (up to 3). If we look at the generated G-code with this option enabled, the bridging layer is printed at a low speed. Combined with the extra cooling, you can solidify the deposited filament before it has time to stick to the already printed structure:

[![Slice with "Enable Bridge Settings"](https://i.sstatic.net/U4RuRAED.png)](https://i.sstatic.net/U4RuRAED.png)

Without this option enabled, the speed would be unaffected and the filament would not have time to solidify:

[![Slice without "Enable Bridge Settings"](https://i.sstatic.net/IxxCUyAW.png)](https://i.sstatic.net/IxxCUyAW.png)

> **Comments:**
> **username_0**: Thank you for the detailed answer! I was not aware that bridging could create such complex structures or about the technique to cool the filament before it can attach to lower layers.  
> **username_0**: One follow up question... do you know why there is not a continuous outer blue perimeter on the hinge piece in your photo? AKA, why the speed increases when the perimeter is not straight lines? I imagine bridging might not be possible here, but if that is the case, is there anything stopping these curved parts of the perimeter that aren't treated like bridges from attaching themselves to the base?  
> **username_0**: I added two photos to my original question at the bottom. It shows how the hinge is attached to the oblong base in the bottom right hand corner. So the bridge becomes the perimeter of the complex hinge shape, which seems much more complex than a straight-line bridge with two bases/foundations, one at each side. In this case, it seems like the bridge would be made, dry in mid-air using the technique you described, but then sag down ~1mm to rest on the base below. I imagine that would mess up the rest of the print around this hinge since it essentially increases the Z-offset of each layer by 1mm  
> **username_0**: (I know that isn't actually what happens, I'm just trying to understand why so I can use this technique in my own designs)... thank you again!  

---

