<p>I have an <a href="https://www.adafruit.com/product/4090" rel="nofollow noreferrer">object</a> and want to construct a part that the object could be slotted into along the Y-axis.</p>
<p><img src="https://i.sstatic.net/YIQKq.png" alt="object to be slotted" title="object to be slotted" /></p>
<p>If I just subtract the object, I will end up with a hollow that is bigger on the inside so it will not be possible to push the object in.</p>
<p>I would like it if there was an easy way to construct the red “hull” so that it can be subtracted from the purple cube.</p>
<p><img src="https://i.sstatic.net/sa8HE.png" alt="side view of the desired shape" title="side view of the desired shape" /></p>
<p>One possibility seems to be the extrusion of a projection of the object into the Y-plane, though that also includes the pins, which would be too much – those are only at the end.</p>
<p><img src="https://i.sstatic.net/el9T5.png" alt="attempt by extruding a projection" title="attempt by extruding a projection" /></p>
<p>Is there some combination/operation that allows “subtraction by imprinting”?</p>

CC BY-SA 4.0
2021-08-09T12:35:17.917Z
Try extruding only faces pointed in -y direction, and using the resulting object in a boolean operation.
Ezra
CC BY-SA 4.0
2021-08-17T11:13:43.153Z
@Ezra how would I get just the faces pointed in -y direction?
Jan Tojnar
CC BY-SA 4.0
2021-08-17T11:13:49.163Z
In the end, I just added a `showPins` parameter to the module and pass `false` to it when extruding.
Jan Tojnar
<openscad>
Creating a hole into which an object can be pushed
Jan Tojnar
# Creating a hole into which an object can be pushed

(Asked by: username_0 on 2021-08-07)

I have an [object](https://www.adafruit.com/product/4090) and want to construct a part that the object could be slotted into along the Y-axis.

![object to be slotted](https://i.sstatic.net/YIQKq.png "object to be slotted")

If I just subtract the object, I will end up with a hollow that is bigger on the inside so it will not be possible to push the object in.

I would like it if there was an easy way to construct the red “hull” so that it can be subtracted from the purple cube.

![side view of the desired shape](https://i.sstatic.net/sa8HE.png "side view of the desired shape")

One possibility seems to be the extrusion of a projection of the object into the Y-plane, though that also includes the pins, which would be too much – those are only at the end.

![attempt by extruding a projection](https://i.sstatic.net/el9T5.png "attempt by extruding a projection")

Is there some combination/operation that allows “subtraction by imprinting”?

**Tags:** openscad

> **Comments:**
> **username_1**: Try extruding only faces pointed in -y direction, and using the resulting object in a boolean operation.  
> **username_0**: @username_1 how would I get just the faces pointed in -y direction?  
> **username_0**: In the end, I just added a `showPins` parameter to the module and pass `false` to it when extruding.  

---

## 0 answers

