problems with extrude

Anonymous · ‎09-27-2021

Hey guys, I need some help. every time I go to extrude a mesh I have made, i get some funky stuff showing into it. Maybe one of you have seen this before and can help me out.

jeff_strater · ‎09-27-2021

without seeing the design itself, this looks like a graphics problem. Try selecting the body, right click and choose "Display Detail Control":

Then, choose "fixed", and try each of the different fixed settings to see if this problems goes away:

Jeff Strater
Engineering Director

Anonymous · ‎09-28-2021

Thank you for trying, but unfortunately it didn't solve my problem.

jeff_strater · ‎09-28-2021

@Anonymous - please share an example model here. At the very least, we can investigate what is going on with this model. Thanks.

Jeff Strater
Engineering Director

TheCADWhisperer · ‎09-28-2021

@Anonymous wrote:
Hey guys, I need some help. every time I go to extrude a mesh I have made,...

I suspect that when you say "mesh" you don't mean in the sense that we normally refer to Mesh features in CAD.

The proper phrase should probably have been, "...extrude a sketch."

I suspect that you created an unnecessarily complex sketch rather than a simple sketch and Pattern Feature or Face (much more robust technique).

I suspect that your sketches are not fully defined (not using best practices in modeling).

Can you File>Export your *.f3d file to your local drive and then Attach it here to a Reply?

Anonymous · ‎09-28-2021

Yes I understand what you mean in the sense of a different kind of mesh, but in fabrication and real world mesh is a sense of hole pattern into something, so forgive me on that. Also, I know it is not ideal to have underdefined sketch, but the deal is that I have created it using rectangular sketch pattern then just deleted what I didn't need, and as far as the main frame goes i copied and pasted from another drawing. I have been using CAD for quite some time now, started with Autodesk Inventor then was using Solidworks before through school, but at my work ive been using bob cad, which is not great so been trying to explore fusion, so kinda new but also not. I appreciate y'all trying to help me out. I've attached the file and maybe you guys can understand what is going on

TheCADWhisperer · ‎09-28-2021

@Anonymous wrote:
I have been using CAD for quite some time now, started with Autodesk Inventor then was using Solidworks before through school...

When I start to diagnose your geometry - none of it makes sense to me in inch or in metric units?

Did you intend for those top lines to be at 0.833256941000621°?

Anonymous · ‎09-28-2021

my units are in inches, and yes, the shape is exactly as it should be.

TheCADWhisperer · ‎09-28-2021

@Anonymous wrote:
... the shape is exactly as it should be.

I'll move on then.

From my experience - I see ~~rubbish~~ (err, I'll call it "art"). Lots of dimensions that cannot possibly be measured in the real world.

Good luck!

Anonymous · ‎09-28-2021

I unerstand, but this piece fits into another that is already set in sizing, they are , we will say.. rough numbers, because i do not have nor can I get the exact piece, and for what I am doing, I do not need say aerospace precision.

Anonymous · ‎09-28-2021

However, because you pointed that out I was looking and I did notice that some of the sides were not of equal length. this part should be mirrored between the two sides straight down the middle.

Anonymous · ‎09-28-2021

But as i have said, this was pulled from a bobcad file, which most people in the cad community knows that program, they understand the struggle. Not a very "strong" program.

jeff_strater · ‎09-28-2021

thanks for sharing the model, @Anonymous - I can verify that what you are seeing here is the graphics bug I was referring to. I was able to get it to work by specifying a "fixed" display detail, set to "Medium":

before:

after setting the detail to fixed/medium:

However, that level of detail is pretty expensive to compute (it took a couple of minutes on my machine). I believe that this is due to a bug that has already been fixed, but not released yet. So, just be aware of that cost.

I was also able to get it to go away using a couple of "split face" features - this just breaks up the face facets, and can help in these cases (this model is attached).

the geometry here is OK, it's just that the top and back face is split

Jeff Strater
Engineering Director

TheCADWhisperer · ‎09-28-2021

@Anonymous wrote:
... they understand the struggle. Not a very "strong" program.

I will try to work up a "best practices" example of how I would model the part (from scratch) within reasonable manufacturing tolerances (I worked out on the shop floor as a machinist for 8 yrs and expect to see nothing beyond 3 decimal places on a part like this. Usually the dimensions are nice "clean" round-offs or common fractions.

I will create one Extrude Thin Feature Hex and then Pattern.

I will Extrude - Intersect to remove excess pattern beyond boundary.

I will Extrude the boundary.

The file will be significantly more robust and easy to edit (if you don't like the dimensions that I settle on).

TheCADWhisperer · ‎09-30-2021

Bump!

Just bumping this to the top so that it doesn't get lost.

I am working on a simplified solution.