# Simple way to taper a cylinder by setting diameter

**URL:** <https://discourse.shapr3d.com/t/simple-way-to-taper-a-cylinder-by-setting-diameter/38578>\
**Category:** Modeling Questions\
**Created:** [June 29, 2025, 3:17pm UTC](https://discourse.shapr3d.com/t/simple-way-to-taper-a-cylinder-by-setting-diameter/38578 "2025-06-29T15:17:18Z")\
**Posts on this page:** 8\
**Page:** 1

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**Author:** ![I-AM-THE-BORG](https://avatars.discourse-cdn.com/v4/letter/i/3e96dc/32.png) [@I-AM-THE-BORG](https://discourse.shapr3d.com/u/I-AM-THE-BORG)\
**Post date:** [June 29, 2025, 3:17pm UTC](https://discourse.shapr3d.com/t/simple-way-to-taper-a-cylinder-by-setting-diameter/38578/1 "2025-06-29T15:17:18Z")

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Hi, i am really new to Cad stuff, I’ve been looking on you tube but I cant work it out please can you help.

I believe it should be a really simple task, but is made un-necessarily hard buy cad programs. (i am old ish 52)

I can create a cylinder.  
I want the bottom to be 75mm  
the top to be 89mm

Once I have created the cylinder, why cant I just click each top then bottom face and set the diameter separately and the walls automatically align?

I Did manage to crate a tapered cylinder, but then I cant see anyone of ensuring the diameter of the top and bottom is what I want. such a simple task.

any help or advise please.

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**Author:** ![Xdrakosha](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.shapr3d.com/xdrakosha/32/24881_2.png) [@Xdrakosha](https://discourse.shapr3d.com/u/Xdrakosha)\
**Post date:** [June 29, 2025, 3:28pm UTC](https://discourse.shapr3d.com/t/simple-way-to-taper-a-cylinder-by-setting-diameter/38578/2 "2025-06-29T15:28:05Z")

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30 sec task

To change sizes:

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**Author:** ![I-AM-THE-BORG](https://avatars.discourse-cdn.com/v4/letter/i/3e96dc/32.png) [@I-AM-THE-BORG](https://discourse.shapr3d.com/u/I-AM-THE-BORG)\
**Post date:** [June 29, 2025, 3:50pm UTC](https://discourse.shapr3d.com/t/simple-way-to-taper-a-cylinder-by-setting-diameter/38578/3 "2025-06-29T15:50:02Z")

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Thank you very much, even after seeing your video, I had a hard time getting the copy bit to show, it didn’t just pop up like in your video.

You solved the issue and I have created thank you.

But in a program like this, don’t you think it would be “easier” just to be able to create a cylinder then amend the top and bottom diameter? seemed quite long winded.

thank you very much for your help, and patience.

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**Author:** ![SCALEMODEL](https://avatars.discourse-cdn.com/v4/letter/s/77aa72/32.png) [@SCALEMODEL](https://discourse.shapr3d.com/u/SCALEMODEL)\
**Post date:** [June 29, 2025, 3:54pm UTC](https://discourse.shapr3d.com/t/simple-way-to-taper-a-cylinder-by-setting-diameter/38578/4 "2025-06-29T15:54:39Z")

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There is another method, since we have the calculator you can scale it (but has disadvantages).

The disadvantage is when you scale it, it turns mathematical circle into SPLINE circle so you can’t get diameter from the measurements.

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**Author:** ![Xdrakosha](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.shapr3d.com/xdrakosha/32/24881_2.png) [@Xdrakosha](https://discourse.shapr3d.com/u/Xdrakosha)\
**Post date:** [June 29, 2025, 3:56pm UTC](https://discourse.shapr3d.com/t/simple-way-to-taper-a-cylinder-by-setting-diameter/38578/5 "2025-06-29T15:56:21Z")

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> [@I-AM-THE-BORG](#):
>
> But in a program like this, don’t you think it would be “easier” just to be able to create a cylinder then amend the top and bottom diameter? seemed quite long winded.

No, I don’t think so. What you’re describing would work for very simple tasks, but for serious modeling, this approach is much better.

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<div class="post-metadata">

**Author:** ![Xdrakosha](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.shapr3d.com/xdrakosha/32/24881_2.png) [@Xdrakosha](https://discourse.shapr3d.com/u/Xdrakosha)\
**Post date:** [June 29, 2025, 4:00pm UTC](https://discourse.shapr3d.com/t/simple-way-to-taper-a-cylinder-by-setting-diameter/38578/6 "2025-06-29T16:00:35Z")

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> [@SCALEMODEL](#):
>
> There is another method

I thought about showing this approach, but decided not to. 🙂

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**Author:** ![SCALEMODEL](https://avatars.discourse-cdn.com/v4/letter/s/77aa72/32.png) [@SCALEMODEL](https://discourse.shapr3d.com/u/SCALEMODEL)\
**Post date:** [June 29, 2025, 4:06pm UTC](https://discourse.shapr3d.com/t/simple-way-to-taper-a-cylinder-by-setting-diameter/38578/7 "2025-06-29T16:06:16Z")

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> [@Xdrakosha](#):
>
> I thought about showing this approach, but decided not to. 🙂

Ya popped in my head because I see Tigermike scaling to achieve similar results, it is less steps but still what you showed would be considered correct.

Because when you scale, I found mathematical circles turn into splines when you project, and sometimes splines are not clean.

Even though more steps, its just the way its done in 3DCAD in this side of things.

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**Author:** ![Xdrakosha](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.shapr3d.com/xdrakosha/32/24881_2.png) [@Xdrakosha](https://discourse.shapr3d.com/u/Xdrakosha)\
**Post date:** [June 29, 2025, 4:08pm UTC](https://discourse.shapr3d.com/t/simple-way-to-taper-a-cylinder-by-setting-diameter/38578/8 "2025-06-29T16:08:35Z")

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> [@SCALEMODEL](#):
>
> Because when you scale, I found mathematical circles turn into splines when you project, and sometimes splines are not clean.

Even worse, sometimes during scaling, four decimal places aren’t enough — and as a result, the shape ends up being slightly off in size.