# Modeling question: How to achieve smooth transition between solid body and closed end surface for a bike saddle?

**URL:** <https://discourse.shapr3d.com/t/modeling-question-how-to-achieve-smooth-transition-between-solid-body-and-closed-end-surface-for-a-bike-saddle/41661>\
**Category:** Modeling Questions\
**Tags:** discourse, featured\
**Created:** [September 19, 2026, 5:25am UTC](https://discourse.shapr3d.com/t/modeling-question-how-to-achieve-smooth-transition-between-solid-body-and-closed-end-surface-for-a-bike-saddle/41661 "2026-09-19T05:25:15Z")\
**Posts on this page:** 1\
**Showing post:** 17

<div class="post-metadata">

**Author:** ![istvan\_u\_Shapr3D](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.shapr3d.com/istvan_u_shapr3d/32/37910_2.png) [@istvan\_u\_Shapr3D](https://discourse.shapr3d.com/u/istvan_u_Shapr3D)\
**Post date:** [October 23, 2026, 11:22am UTC](https://discourse.shapr3d.com/t/modeling-question-how-to-achieve-smooth-transition-between-solid-body-and-closed-end-surface-for-a-bike-saddle/41661/17 "2026-10-23T11:22:56Z")

</div>

Hey, we’ve released the Fill tool which can be used in exactly these situations.

While it’s not surfacing as you might know it from Rhino, it’s a tool that should let you create forms that weren’t possible before in Shapr.

We are still working on improving this tool and we’ll soon add a couple of new features like bridge curves that will make it more powerful.

You can read more about it here: [26.190 - Introducing Fill Tool (Beta)](https://discourse.shapr3d.com/t/26-190-introducing-fill-tool-beta/42386)

Give it a try and let us know what you think!

---

_[View the full topic](https://discourse.shapr3d.com/t/modeling-question-how-to-achieve-smooth-transition-between-solid-body-and-closed-end-surface-for-a-bike-saddle/41661)._