This will work for many objects and not for others. There are infinitely many ways meshes can be broken and non-manifold. If this isn't working for you, then your mesh likely requires a human to inspect and repair the defects.

You can avoid the double load time by deselecting the "Realtime" view. It is one of the 3 small buttons on the right side of the word "Boolean". If you have the "Realtime view" deselected it only loads once, when you press "Apply"

I am using Blender Version 4.1.0 (4.1.0 2024-03-26) and unfortunately did not have the same luck with this particular approach. The "Self" intersect method is not longer an option. I attempted a similar workaround where I applied the modifier to the cube and used "intersect", and it appeared in the viewfinder to have similar results, but it didn't fix my manifold issues. I am saying this in hopes that this alternate approach works for others and that it was just a personal issue with my particular geometry. Another approach that did work for my geometry was the "Remesh" modifier. I used the "Voxel" approach in the remesh function with a sufficiently small mesh to grab all the fine curvature of my model. This worked, but warning that it was very memory intensive. It took me a couple iterations to find a sufficiently small resolution size such that it (1) captured all of the curves in my model and (2) didn't crash my application because of how small I was refining. Good luck out there!

Man, I watched dozens of videos using face orientation, solidify, shrink-wrap modifier, and a few other ways. This is the only one that worked.

Holy moly you're a genius, I've had so many problems making meshes in blender never once did I think of this

Literally a life saver! Been trying to 3d print some game models that were definitely not meant to be manifold and Cura was going nuclear lol

Perfect solution! Allowed me to print two minfigs that I've spent hours trying to fix. As always the simplest solution is the bet one - Many thanks!!!

I've been struggling with this exact problem for so long when modeling in Blender. I'm not kidding .... this is (jokingly) life saving.

thanks man that was so clear, easy and informative ive been watching videos learning BLENDER and so far you are the best.

Thank you for this tutorial!!! I've been 3d scanning trim pieces in my truck and the output is always non manifold big pile of vertices. I had to ensure I solidifies the faces first and also made sure that materials in the modifier is set to transfer from the cube. 🎉

I kid you not I was converting a Game model into a printable 3D model and only 1, face was broken. I retried converting it many times. You just saved my computer from its first flight.

This is the very stl I was trying to fix. I'm making my daughter a Hobbit bookcase diorama for Christmas. You've earned another subscriber, thanks.

LOL! "Borg Cube this" Seriously I really appreciate this fix. I don't 3D print, but I make a habit of being absolutely certain that ALL my objects are completely free of any Non-Manifold issues before and after doing a Boolean operation. I often work with truly HUGE models (like a ship over a mile long), and with having people walking around in it I've found that pretty much any Non-Manifold issues, although not visible in long shots like (exterior establishing shots) renders look fine, but in comparatively close in shots (like two people walking through where a 50 foot diameter transfer tunnel intersects with a complex object that forms a part of the ship that's more than 1800 feet across) tiny Non-Manifold issues will cause artifacts twice the size of a man and be VERY apparent. Prior to finding your solution this could be a horrendously time consuming problem to fix. Thank you for posting this!

Thank you! Didn’t work for me but this is exactly what I need to fix so I’m getting closer at least…

"What the flapjacks!" lol Great tutorial! Thank you very much!

DUDE! You saved me HOURS of work!

This turned a model that had 30 errors into a model with 106 errors. lol. I don't doubt that it works most times. But I applied it to a file that windows 3d wont even fix so i am not surprised it didn't work. I appreciate the tip though. Typically the windows "3d Builder" does a great job at fixing a few manifold issues but it struggles with really big files regardless of number of errors. But I recommend trying it if this blender method doesn't work. Though the current file I am having issues with won't fix with either of them.

THANK YOU! I have been importing my files into freeCAD or other programs and sometimes it worked and sometimes it didn't. This is way better and works with my own blender-created files that I create and clean up for later distribution. Much appreciate this video.

You saved my life king❤

Wow!! I’ve been looking for this for ages. Thank you 🙏🏻

Man I feel like i owe you more than just a like and sub. This is the best quick fix I've seen to date. Thank you!

Probably check Face Normals are pointing outwards first!

Have you seen the 3D Printing Toolbox add-on that comes with Blender? There is a "Make Manifold" button. Now I do always turn this on but I think I've never hit that button. Maybe quicker way

you saved my life.

there is an addon in blender mesh/print 3D print tool box

Did this on a Apex legends Octane model from CGTrader. It originally had 1933 non Manifold edges. When I used this solver it went up to 12667 Non manifold edges

Amazing! Simple fix to such a pain in the @$$ issue. Thanks for posting this!

BLESS YOU! I had this posed figure from a game I wanted to print and this helped fix the model for printing!!!

Genius. Saved me a lot of time. Thanks!

Nice, I was trying to do this with unions but this is much better. Thank you!!

300 manifold thingies before, 500 after.. Guess it didn't work for me. Sure wish I knew how to fix this.

The only thing I have understood is the ad for the soap that came before.

thank christ bro. good work.

thank you so much you saved me a ton of time with that trick. up until this point i used to remash the model to fix that broblem...

Thank you very much! I've been stuck with an issue for days and this was so easy to fix. Thank you, God bless

Blender is the nipslip of 3d modelling software 😂. Thanks dude

Thank you for this straightforward demonstration. So...much...time...saved.

You are The Man👊

I don't understand a damn thing, but it's very interesting

This increased my non-manifold edges from 240 to 602 lmao

Thanks so much for this. I've been using blender for many years, and somehow this fix had slipped pass through me

Your video saved my project!

Thank you so much!

Did not work - some of the options are different in the boolian setting - wish there was a newer version of this tute.

Many thanx friend, solved my boolean issue due to non manifold, perfect!

Looks like a great tool! Sadly, when adding Boolean I do not have the same options as you. There is no "solver" or "self" check box.

One of these days, I need to learn Blender

Dang, I gotta try this. I learned a lot of blender to fix parts manually, this would have been a lot easier. I guess I did learn a lot on the way though.

when i put the modifier in the object dissapears from wireframe

There is another solution. Import the model into fusion 360 and turn it into a mesh. Then export that file as an stl and it will be manifold.

hello, i tried to do it but the object i am healing disappeared . I would like to know what to do in this case , any advice ?

Thank you VERY MUCH ! Very straightforward method ! all others use a bunh og complicated steps..

It works only partially for me- it only separates the intersecting meshes, without actually removing anything. Help?

THANKS MAN THAT'S A BIG HELP

this didn't work for me unfortunately. when i throw it into a slicer, it comes up still broken and can't be fixed

My Non-Manifolds actually doubled after trying to do that xD xD

Did someone say 🥞's? Great video, thanks!

amazing saved me so much time!

Thanks a lot!

This video explains 7 different non-manifold issues and how to fix them all. See kzfaq.info/get/bejne/bZ6XrKdpmri2mqM.html

you are a life saver man

when I try this with a larger Geometry the model disappears after a long calculation time, any idea what might be happening? the model is an rc shell

Incredible tip brother.

i twitched a bit when you didnt delete the default cube

Thanks Man! Helped a lot! 👍

Thank you so much for 👍👍

Very smart

It worked thank you!

i try this and blender keeps crashing on me :/

Hi,, Thanks for the video, i have downloaded the same file exactly , and i followed your steps one by one, but unfortunately didn't work..Knowing that i am using Blender 4.0

This isn't working for me. I have the object engulfed by the cube, add the boolean modifier to the object, select intersect, self, then select the cube as object, apply and when I go back to the object and select all non-manifold veriticies it's the same as before. .

So, when I hit cube and after it "thinks" the object I'm healing disappears entirely, but its still on the objects menu, I just can see it any longer. Any advice for that? Ive seen no one address it.

work. Thank you bro.

thanks alot for the video

What version of Blender are you using? I'm using 2.8 or 3.00 and neither have the self tickbox.

Thank you for the tutorial

Broh! Really Thanks

great one

that didn't work at all for me. the object just dissapeared. like it had been reduced to 1 pixel

What is ticking on "self" for?

All the controls to perform this manifold operation not showing in my installed version. WHY?

Thank you!

Thank you, sir!!

i love you so much ty

didnt work at all. still had non manifold edges and repairing them still fucked up my model

Help please! I found this video as it's exactly what I'm trying to fix. My issue is that when I try and select the 'cube' in Object, it isn't listed. The original cube from when blender started up.... I did try the operation by selecting my STL object... but the STL did not get repaired. So I'm not sure if it matters whether the cube or my object is selected. Any thoughts on how to get the cube to appear in the Object list?

"WTFjcets" 🤣

YOU ARE AMAZING! THANK UU SOOOOOOOOOOO MUCH! You dont have any idea how you help me

This just doesn't work for my model...

Thankssssss

Which it worked for me on an M18 battery adapter, but did not. Still thanks for doing the video.

so I followed what you did bro and it deleted the whole model and left 1 vertice. Did i do something wrong : (

didnt work

sounds amazing!!! but even disabling the Render my blender Crashes! :( it stays iddle on Apply and then crashes. is any solution to this?

Mine doesnt have that "self" option...or i just dont know how to access it

Will this fix bad geometry data error while printing?

Omg thx

It did not help absolutely...

Didn't work

did not solve the problem, from 2000 non-manifold, it went to 40000 non manifold :) great ...