# Preform not repairing model

**URL:** <https://forum.formlabs.com/t/preform-not-repairing-model/12141>\
**Category:** General Discussion\
**Created:** [March 2, 2017, 2:22am UTC](https://forum.formlabs.com/t/preform-not-repairing-model/12141 "2017-03-02T02:22:14Z")\
**Posts on this page:** 6\
**Page:** 1

<div class="post-metadata">

**Author:** ![Scote](https://sea1.discourse-cdn.com/flex025/user_avatar/forum.formlabs.com/scote/32/8838_2.png) [@Scote](https://forum.formlabs.com/u/Scote)\
**Post date:** [March 2, 2017, 2:22am UTC](https://forum.formlabs.com/t/preform-not-repairing-model/12141/1 "2017-03-02T02:22:14Z")

</div>

Look like every time I import a model. It’s asking to repair. But the repair buttom do nothing. Is it not suppose to display a progress bar or something?

---

<div class="post-metadata">

**Author:** ![Dudemeister](https://sea1.discourse-cdn.com/flex025/user_avatar/forum.formlabs.com/dudemeister/32/13812_2.png) [@Dudemeister](https://forum.formlabs.com/u/Dudemeister)\
**Post date:** [March 2, 2017, 2:51pm UTC](https://forum.formlabs.com/t/preform-not-repairing-model/12141/2 "2017-03-02T14:51:44Z")

</div>

usually it does show a progress bar, unless the repair was so minor and took so little time, that it didn’t have time to display it.

Does the model look OK ? Does it print OK?

---

<div class="post-metadata">

**Author:** ![CraigBroady](https://sea1.discourse-cdn.com/flex025/user_avatar/forum.formlabs.com/craigbroady/32/6106_2.png) [@CraigBroady](https://forum.formlabs.com/u/CraigBroady)\
**Post date:** [March 2, 2017, 9:00pm UTC](https://forum.formlabs.com/t/preform-not-repairing-model/12141/3 "2017-03-02T21:00:46Z")

</div>

You mean that the model doesn’t show up in PreForm at all? I have this happen sometimes, too. The bug relates to an unusual edge case for some STL files.

Using Netfabb basic (free), I convert the STL to OBJ and the problem is solved. Not a perfect solution, but it works until the larger issue is solved in a future PreForm release.

---

<div class="post-metadata">

**Author:** ![Scote](https://sea1.discourse-cdn.com/flex025/user_avatar/forum.formlabs.com/scote/32/8838_2.png) [@Scote](https://forum.formlabs.com/u/Scote)\
**Post date:** [March 3, 2017, 12:05am UTC](https://forum.formlabs.com/t/preform-not-repairing-model/12141/4 "2017-03-03T00:05:18Z")

</div>

Thanks guys,

So no the progress bar doesnt shjow and the model doesnt show. So I guess the model never get repaired.

ANy way I will try the Netfabb approach. Let’s see

---

<div class="post-metadata">

**Author:** ![sloh](https://avatars.discourse-cdn.com/v4/letter/s/f19dbf/32.png) [@sloh](https://forum.formlabs.com/u/sloh)\
**Post date:** [March 17, 2017, 2:35pm UTC](https://forum.formlabs.com/t/preform-not-repairing-model/12141/5 "2017-03-17T14:35:02Z")

</div>

Yeah,happen to me a couple of times too,  
before you use netfabb, check if your stl files are extracted from zip files. Preform cannot repair if it is not extracted yet.

Sometimes i have to use netfabb to repair, saved it to new name, Then open with preform.

---

<div class="post-metadata">

**Author:** ![Digitalsmithy](https://sea1.discourse-cdn.com/flex025/user_avatar/forum.formlabs.com/digitalsmithy/32/16725_2.png) [@Digitalsmithy](https://forum.formlabs.com/u/Digitalsmithy)\
**Post date:** [March 20, 2017, 11:39pm UTC](https://forum.formlabs.com/t/preform-not-repairing-model/12141/6 "2017-03-20T23:39:32Z")

</div>

I’ve had this happen and found out there was some inverted normals on part of my mesh. Once I flipped them it worked like a charm.