Having issues with a pocket

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andy.wpg
Posts: 23
Joined: Sun Jun 05, 2022 1:43 am

Having issues with a pocket

Post by andy.wpg »

I am trying to design stick protectors for my various RC transmitters. This is the first one.

No problem, really, until I get to cutouts to lighten the cone shape.

It won't allow me to attach to the face of the lofted cone. I then created the sketch on the XY plane, and tried positioning it at various heights, both touching the loft, and not touching the loft. What it seems to create is a shell, "enclosing" the shape, as in the screen capture below.
Strange_pocket.JPG
Strange_pocket.JPG (22.67 KiB) Viewed 618 times
I tried exporting it as a STEP, but PrusaSlicer won't even open it, complaining about a zero size file.

Not sure what I'm doing wrong. Any assistance would be appreciated.

Andy
Attachments
Stick protector.FCStd
(69.77 KiB) Downloaded 22 times
"I have noticed even people
who claim everything is predestined,
and that we can do nothing to change it,
look before they cross the road."

Stephen Hawking
Bance
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Posts: 4187
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Location: London

Re: Having issues with a pocket

Post by Bance »

Swap the dim's in Sketch002.....

Bullet point no5.

https://wiki.freecad.org/PartDesign_AdditiveLoft#Notes
Last edited by Bance on Sun Jun 04, 2023 6:58 pm, edited 1 time in total.
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Willem
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Location: Lisse, The Netherlands

Re: Having issues with a pocket

Post by Willem »

In addition to Bance in all 3 sketches the first circle has to be the outer diameter and the second circle has to be the inner diameter. In your model you can see that the circles are twisted
Schermafdruk van 2023-06-04 20-53-35.png
Schermafdruk van 2023-06-04 20-53-35.png (126.31 KiB) Viewed 571 times
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Shalmeneser
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Re: Having issues with a pocket

Post by Shalmeneser »

You can see in your picture that the middle sketch is incorrect.

Do you really need a loft feature ? A PartDesign_Revolution would provide better control.
Your last pocket should be "symmetric" and "through all".
kisolre
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Re: Having issues with a pocket

Post by kisolre »

Your loft is wrong. When lofting between sketches with multiple contours the order of contours in the sketch is important since loft is not smart enough to determine which is inside and whish outside (for now hopefully) and uses them in the order they are created in the sketch. Here your sketches are simple so simply redimensioning should work. Check 5th note here: PartDesign_AdditiveLoft.
Here is a fixed file:
Stick protector_kiss.FCStd
(68.08 KiB) Downloaded 17 times
Edit: Sorry if it looks like a rant, that happens when you leave a tab open for too long :)
andy.wpg
Posts: 23
Joined: Sun Jun 05, 2022 1:43 am

Re: Having issues with a pocket

Post by andy.wpg »

Thank you all! I do know about the order. I must've been tired when I did that.
Correcting the middle sketch fixed it.
I did consider doing it as a profile and revolving it, but i decided doing it this way gave me more control later when I need to refine it. My thinking was that I'm designing this as I go, and a profile might be more difficult to modify. It was probably the wrong choice, but I guess I'll live with it now.
Part of it was also that this is only half, and I need to mirror it to create the other side. So, essentially, I'm building the left half.

Thanks again all!
"I have noticed even people
who claim everything is predestined,
and that we can do nothing to change it,
look before they cross the road."

Stephen Hawking
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