I can't make clean holes when slicing with cura

[Tanooki2022 0]

Hopefully someone can help me.

I use tinkercad . I'm a newbie 🙂

I made a simple round base empty inside with 2 small holes (one hole is round and one hole is rectangular).

I can see them in cura but when i slice it, it put's a wall behind the holes. So much for making a hole :0)

I must be missing a setting somewhere. I've looked online and haven't found anything to help with this issue. Your help is greatly appreciated!

See attached pics.

What cura shows/slice  prints exactly the same!

[AndersK 59]

Look in your cad model tree if there are any surfaces left after you cut the holes.

Delete those and export STL again. 

Seen this before causing same issues but from other cad

[gr5 2,167]

Something is strange.  Do you have infill turned off?  Is this spiralize mode?  Maybe you should post your project file (do "file" and then "save project as" or something like that.  Then post the result which will include all your settings and your model(s).

[Tanooki2022 0]

Well I can't explain it for some reason this morning it worked . WOOHOO!!!

I used the exact same settings and same file. I just reslice it now and it's fine.

Thank you for trying to help out!

I'm not sure do I need to delete this post ?

[Tanooki2022 0]

On 2/26/2022 at 8:29 PM, AndersK said:

Look in your cad model tree if there are any surfaces left after you cut the holes.

Delete those and export STL again. 

Seen this before causing same issues but from other cad

So I tried a simple box with 1 hole or 2 holes and I get the same result it outlines the back of the hole.

I use tinkercad. I'm not sure how I can look at the cad model tree. Please explain further.

Is there a dept. preference when you make a hole or can it be any dept?

in Cura i do see the outline of the holes inside the box. fill is UNchecked.

I checked my first project I originally wrote and I didn't alter it and suddenly when I re-sliced it in Cura it was great. perfect hole. I haven't been able to reproduce this with any other project.

[Tanooki2022 0]

Here's the stl file. I'm not sure how else I can save the file using tinkercad

Copy of test hole.stl

[GregValiant 1,248]

When @gr5 refers to a Cad model tree I believe he is talking about the list of operations that have been performed.  There would be the initial extrusion, and you have two holes.  The tree for that model would have those three items in it.

You have a 63mm cube with two 20mm diameter holes.  One hole is 6mm deep to a flat bottom and the other hole is 19.83mm deep to a flat bottom.  I didn't find any errors in the model and it sliced just as it looks like it should.

Edited February 28, 2022 by GregValiant

[gr5 2,167]

Tanooki please show a photo of what is wrong.  It sounds like your model isn't the shape you think it is.  

 

Also, it would be good if you could post a "project file".  In cura go to "save" and "save project as" and post that file here.  That will include your printer settings, your profile, your overrides, your model, and how you positioned your model.  Basically everything we need to replicate what you are seeing.

[Tanooki2022 0]

9 hours ago, GregValiant said:

When @gr5 refers to a Cad model tree I believe he is talking about the list of operations that have been performed.  There would be the initial extrusion, and you have two holes.  The tree for that model would have those three items in it.

You have a 63mm cube with two 20mm diameter holes.  One hole is 6mm deep to a flat bottom and the other hole is 19.83mm deep to a flat bottom.  I didn't find any errors in the model and it sliced just as it looks like it should.

Umm strange. Doesn't work for me. However i figured out something interesting. If I create a shape and remove the "inside"  and make a hole very thin (the size of the wall) then cura allows me to print with a perfect hole.

If I don't empty the inside of the item before I import the stl file cura won't make a clean hole.

Thank you all for helping me

[Tanooki2022 0]

8 hours ago, gr5 said:

Tanooki please show a photo of what is wrong.  It sounds like your model isn't the shape you think it is.  

 

Also, it would be good if you could post a "project file".  In cura go to "save" and "save project as" and post that file here.  That will include your printer settings, your profile, your overrides, your model, and how you positioned your model.  Basically everything we need to replicate what you are seeing.

Please see attached file. I had deleted the previous file because it didn't work. Here's  a new one with the same problem. If I empty the "shape" before I go to cura then it works fine. Is that normal practice?

CE5P_test holes.3mf

[GregValiant 1,248]

"...but when i slice it, it put's a wall behind the holes."

I think what we have here is "expected behavior".

Typically, a model is a solid through-and-through.  When you put a bore in it's like drilling a flat bottom hole into a piece of wood.  If that hole doesn't go all the way through then there will be a bottom.  Setting Infill Density to "0" doesn't change that.

If you want a piece like you show (a cup with two holes in the wall and open into the interior) then it needs to be designed that way.

The smaller model here is your cube and the larger one is my design.  In CAD - I added a "shell" feature (emptied the interior) and ignored the top (so it has a top opening) and then extruded a 24.4mm tube 20mm long through the side wall.  Then I cut a 20mm diameter hole through the tube.  That left the walls of the tube 1.2mm thick.  The other two holes are just through the wall.  Since there is no "interior" because of the shell feature, there are no bottoms in the holes.  The 3mf file I've attached has both models.  My model would require support on the inside to hold the tube up while it is printing.

 

GV_CE5P_testholes.3mf

Edited March 1, 2022 by GregValiant

[gr5 2,167]

Everything looks fine.  You modeled a box with two shallow entries into the box.  And that's what cura wants to print.

 

 

However I think I understand what is bothering you.  You want a hollow box?  If so you need to model a hollow box in CAD.  You can't model a solid box in CAD and expect Cura to slice it hollow for you.

 

The "wall" setting in cura has nothing to do with how thick the walls will be (well sort of - it's confusing you I think).  If you want a box with 3mm thick walls then you have to model that in Tinkercad.  Not set that in Cura.  And by the way keep your walls at least 1mm thick in tinkercad until you are an expert.

 

I think you are independently, slowly coming to that realization already from what you said in your most recent post.  So, "yes, you need to hollow out the box yourself".

[gr5 2,167]

I should mention that it's a little frustrating when we ask you questions to try to help you and you ignore them.  Like "did you turn on spiralize?" and "did you set infill to 0%".  Of course I have the answers now that you posted the project file.  Thanks for that.

[Tanooki2022 0]

On 3/1/2022 at 11:05 PM, gr5 said:

Everything looks fine.  You modeled a box with two shallow entries into the box.  And that's what cura wants to print.

 

 

However I think I understand what is bothering you.  You want a hollow box?  If so you need to model a hollow box in CAD.  You can't model a solid box in CAD and expect Cura to slice it hollow for you.

 

The "wall" setting in cura has nothing to do with how thick the walls will be (well sort of - it's confusing you I think).  If you want a box with 3mm thick walls then you have to model that in Tinkercad.  Not set that in Cura.  And by the way keep your walls at least 1mm thick in tinkercad until you are an expert.

 

I think you are independently, slowly coming to that realization already from what you said in your most recent post.  So, "yes, you need to hollow out the box yourself".

Thanks

[Tanooki2022 0]

On 3/1/2022 at 11:09 PM, gr5 said:

I should mention that it's a little frustrating when we ask you questions to try to help you and you ignore them.  Like "did you turn on spiralize?" and "did you set infill to 0%".  Of course I have the answers now that you posted the project file.  Thanks for that.

I'm sorry I was sure I had answered those questions you asked!

[Tanooki2022 0]

On 3/1/2022 at 6:36 PM, GregValiant said:

"...but when i slice it, it put's a wall behind the holes."

I think what we have here is "expected behavior".

Typically, a model is a solid through-and-through.  When you put a bore in it's like drilling a flat bottom hole into a piece of wood.  If that hole doesn't go all the way through then there will be a bottom.  Setting Infill Density to "0" doesn't change that.

If you want a piece like you show (a cup with two holes in the wall and open into the interior) then it needs to be designed that way.

The smaller model here is your cube and the larger one is my design.  In CAD - I added a "shell" feature (emptied the interior) and ignored the top (so it has a top opening) and then extruded a 24.4mm tube 20mm long through the side wall.  Then I cut a 20mm diameter hole through the tube.  That left the walls of the tube 1.2mm thick.  The other two holes are just through the wall.  Since there is no "interior" because of the shell feature, there are no bottoms in the holes.  The 3mf file I've attached has both models.  My model would require support on the inside to hold the tube up while it is printing.

 

GV_CE5P_testholes.3mf 264.25 kB · 0 downloads

Thank you for the info!