# New Dynamic Modeler tools: Hollow, Margin, ROI cut
**URL:** https://discourse.slicer.org/t/new-dynamic-modeler-tools-hollow-margin-roi-cut/24422
**Category:** Support
**Tags:** feature, dynamic-modeler
**Created:** [July 20, 2022, 9:39pm UTC](https://discourse.slicer.org/t/new-dynamic-modeler-tools-hollow-margin-roi-cut/24422 "2022-07-20T21:39:21Z")
**Posts on this page:** 6
**Page:** 1
### Author:  [@lassoan](https://discourse.slicer.org/u/lassoan)
#### Post date: [July 20, 2022, 9:39pm UTC](https://discourse.slicer.org/t/new-dynamic-modeler-tools-hollow-margin-roi-cut/24422/1 "2022-07-20T21:39:21Z")
Dynamic Modeler module allows parametric editing of models. In this post we present three new tools have been added to this module some time ago (by @Sunderlandkyl and @lassoan) but they have not been announced yet.
**Hollow tool:** creates a hollow model (with a specified wall thickness) from a solid surface mesh.
**Margin tool:** shrinks or expands the model by moving all points towards inside or outside, along the surface normals.
**ROI cut tool:** Cuts out or crops a model with a markups ROI box
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### Author:  [@mau\_igna\_06](https://discourse.slicer.org/u/mau_igna_06)
#### Post date: [July 20, 2022, 10:13pm UTC](https://discourse.slicer.org/t/new-dynamic-modeler-tools-hollow-margin-roi-cut/24422/2 "2022-07-20T22:13:37Z")
Great… negative margin appears to be just what we need for more accurate guideBases
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### Author:  [@dokay1](https://discourse.slicer.org/u/dokay1)
#### Post date: [September 21, 2022, 3:39pm UTC](https://discourse.slicer.org/t/new-dynamic-modeler-tools-hollow-margin-roi-cut/24422/3 "2022-09-21T15:39:29Z")
This looks like a fantastic tool! Is there a way to apply these alterations on multiple models or invoke such using a script?
I’m specifically interested in using margin to shrink a large number of models (\>100). It would be too tedious to do one-by-one.
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### Author:  [@jay1987](https://discourse.slicer.org/u/jay1987)
#### Post date: [January 20, 2023, 12:40pm UTC](https://discourse.slicer.org/t/new-dynamic-modeler-tools-hollow-margin-roi-cut/24422/4 "2023-01-20T12:40:28Z")
the extension looks awesome, I really want to try the extension.
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### Author:  [@lassoan](https://discourse.slicer.org/u/lassoan)
#### Post date: [January 20, 2023, 12:51pm UTC](https://discourse.slicer.org/t/new-dynamic-modeler-tools-hollow-margin-roi-cut/24422/5 "2023-01-20T12:51:36Z")
> [@dokay1](#):
>
> This looks like a fantastic tool! Is there a way to apply these alterations on multiple models or invoke such using a script?
>
> I’m specifically interested in using margin to shrink a large number of models (\>100). It would be too tedious to do one-by-one.
You can automate by Python scripting. See example in the [script repository](https://slicer.readthedocs.io/en/latest/developer_guide/script_repository.html#create-a-hollow-model-from-boundary-of-solid-segment).
> [@jay1987](#):
>
> the extension looks awesome, I really want to try the extension
Dynamic modeler module is included in the main Slicer application (no need to install an extension).
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### Author:  [@jay1987](https://discourse.slicer.org/u/jay1987)
#### Post date: [January 20, 2023, 12:53pm UTC](https://discourse.slicer.org/t/new-dynamic-modeler-tools-hollow-margin-roi-cut/24422/6 "2023-01-20T12:53:19Z")
lets say i searched all extensions and github , can’t find the dynamic modeler extension , haha ,thank you @lassoan