# Spline around curve

**URL:** <https://discourse.shapr3d.com/t/spline-around-curve/25659>\
**Category:** Modeling Questions\
**Created:** [May 5, 2023, 10:04pm UTC](https://discourse.shapr3d.com/t/spline-around-curve/25659 "2023-05-05T22:04:07Z")\
**Posts on this page:** 8\
**Page:** 1

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**Author:** ![bigwix](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.shapr3d.com/bigwix/32/20578_2.png) [@bigwix](https://discourse.shapr3d.com/u/bigwix)\
**Post date:** [May 5, 2023, 10:04pm UTC](https://discourse.shapr3d.com/t/spline-around-curve/25659/1 "2023-05-05T22:04:07Z")

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I’m sweeping a ramp shape around a curve, but Im having trouble figuring out how to sweep the last leg of my form. I need / want to have it follow a spline sort of down to a surface but at the same time it needs to follow a curve on another place.

 ![Screenshot 2023-05-05 at 1.59.54 PM](https://us1.discourse-cdn.com/flex002/uploads/shapr3d/original/3X/4/d/4ddb1ef6495f7eb61d2ea0de428fca6dedf48564.jpeg)

Im trying to figure out how to possibly curve the spline on two planes

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**Author:** ![KPeter](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.shapr3d.com/kpeter/32/7644_2.png) [@KPeter](https://discourse.shapr3d.com/u/KPeter)\
**Post date:** [May 8, 2023, 10:14am UTC](https://discourse.shapr3d.com/t/spline-around-curve/25659/2 "2023-05-08T10:14:24Z")

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Can you please share some pictures of the end product? It would help a lot in finding a solution

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**Author:** ![bigwix](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.shapr3d.com/bigwix/32/20578_2.png) [@bigwix](https://discourse.shapr3d.com/u/bigwix)\
**Post date:** [May 8, 2023, 12:36pm UTC](https://discourse.shapr3d.com/t/spline-around-curve/25659/3 "2023-05-08T12:36:02Z")

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![Screenshot 2023-05-08 at 7.12.41 AM](https://us1.discourse-cdn.com/flex002/uploads/shapr3d/original/3X/0/a/0a9e945568ea44d24f6161503c0eee81be19771b.jpeg)

Here’s roughly the same idea from a different angle. I changed the approach from trying to loft that face along the spline in the first pic to just sweeping the same spline around a different axis which I think is what I wanted without realizing it.

The net effect is that the exterior side profile is just a concave curve instead of a combination of convex at the top and concave at the bottom, but I think it’s better in the long run.

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**Author:** ![bigwix](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.shapr3d.com/bigwix/32/20578_2.png) [@bigwix](https://discourse.shapr3d.com/u/bigwix)\
**Post date:** [May 8, 2023, 12:36pm UTC](https://discourse.shapr3d.com/t/spline-around-curve/25659/4 "2023-05-08T12:36:09Z")

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The end goal is a contoured tractor seat for a stool something like:

 ![image](https://us1.discourse-cdn.com/flex002/uploads/shapr3d/original/3X/b/1/b10d497a103639273bf46a81b3a69c9d194dc4f8.jpeg)

but with a bit different contouring

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**Author:** ![TigerMike](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.shapr3d.com/tigermike/32/32650_2.png) [@TigerMike](https://discourse.shapr3d.com/u/TigerMike)\
**Post date:** [May 8, 2023, 4:37pm UTC](https://discourse.shapr3d.com/t/spline-around-curve/25659/5 "2023-05-08T16:37:18Z")

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Here is an approach that might work for you. Note that my finished seat does not exactly replicate the stool seat. I used an ellipse for the sweep and the overall fillet radii can be adjusted differently. Anyway, this might give you some ideas.

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**Author:** ![Stephen](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.shapr3d.com/stephen/32/16350_2.png) [@Stephen](https://discourse.shapr3d.com/u/Stephen)\
**Post date:** [May 8, 2023, 6:13pm UTC](https://discourse.shapr3d.com/t/spline-around-curve/25659/6 "2023-05-08T18:13:59Z")

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That’s really cool Mike. You always come up with something worth waiting for 👍

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**Author:** ![bigwix](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.shapr3d.com/bigwix/32/20578_2.png) [@bigwix](https://discourse.shapr3d.com/u/bigwix)\
**Post date:** [May 8, 2023, 6:51pm UTC](https://discourse.shapr3d.com/t/spline-around-curve/25659/7 "2023-05-08T18:51:34Z")

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Nice. I’ll play around with this approach and see if it gets me closer, as the bottom of that oval is bringing a contour into the model that I started trying to put in after my other contours and was proving complex.

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**Author:** ![TigerMike](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.shapr3d.com/tigermike/32/32650_2.png) [@TigerMike](https://discourse.shapr3d.com/u/TigerMike)\
**Post date:** [May 8, 2023, 9:30pm UTC](https://discourse.shapr3d.com/t/spline-around-curve/25659/8 "2023-05-08T21:30:01Z")

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I played around with this and made some tweaks. This version looks closer.

[https://us1.discourse-cdn.com/flex002/uploads/shapr3d/original/3X/2/5/25af0886b3abd782f08e1acc74d3f9ed79a8ab1a.mov](https://us1.discourse-cdn.com/flex002/uploads/shapr3d/original/3X/2/5/25af0886b3abd782f08e1acc74d3f9ed79a8ab1a.mov)