topic Re: Need help with patches and stitching in Fusion Support Forum

Need help with patches and stitching

jonavark — Thu, 14 Aug 2025 20:30:17 GMT

I am trying to model a guitar neck.

The transitions at the head an heel have been very tough for me.

A while ago I did something to my project and broke the end of the timeline for the neck.

I get a 'modeling error' now at that stitch feature but for the life of me I have no idea what it is.

Also, in this neck model the stitched portions still show seams. ?

I am wondering if I can upload my project file for some input or should I do this via a support ticket?

It should be a private upload as my client doesn't want the file made public.

Thank you.

Betreff: Need help with patches and stitching

g-andresen — Thu, 14 Aug 2025 20:45:39 GMT

`Hi,

You ask for help in a public forum and at the same time state that you do not want this to be made public.

What are we to make of this?

günther

Re: Need help with patches and stitching

Warmingup1953 — Thu, 14 Aug 2025 22:10:53 GMT

The forum works as a forum as you would imagine...

"Forum....a meeting or medium where ideas and views on a particular issue can be exchanged."

If there is IP you can't share publicly but still need assistance, what often works is if you create a proxy file that reveals your problem or area you need assistance without compromising your desired privacy.

Don't forget to include your Fusion file as well as any screen captures to illustrate the issue. Inserting photos is better than attaching them!

Edit: Apologies for the initial non-inclusive AI generated image!

Betreff: Need help with patches and stitching

jonavark — Fri, 15 Aug 2025 00:19:10 GMT

Understood.

Is there any way to drill down into an abstract error message to get hints on what the cause is?

I can't resolve the issue because I have no clue where the error is. Fusion doesn't return much data on errors.

I will try to extract the problem project from the main file and post it here.

Re: Need help with patches and stitching

jonavark — Fri, 15 Aug 2025 00:21:39 GMT

unnecessary, somewhat arrogant.

I would never have known what a forum is without your help.

Betreff: Need help with patches and stitching

g-andresen — Fri, 15 Aug 2025 08:21:02 GMT

Hi,

@jonavark schrieb:

I will try to extract the problem project from the main file and post it here.

That would make sense.

günther

Re: Need help with patches and stitching

jeff_strater — Fri, 15 Aug 2025 12:25:39 GMT

as discussed, having your design or a cut-down version of it is the best way to get support. However, you can maybe get some ideas from other Forum users. This topic has come up quite a lot over the years (I have done some guitar modeling myself, so I pay special attention to that topic). Those two transitions (neck heel and headstock) seem, for some reason, to be particularly difficult surface modeling challenges. Everyone who tries to do this seems to encounter issues. A quick search of the forum returns a fair number of articles. I just searched for "guitar neck": https://www.autodesk.com/search?qt=guitar%20neck&sn=en_US&us_op=forums

Re: Need help with patches and stitching

jonavark — Fri, 15 Aug 2025 17:15:19 GMT

Thank you. Yes. I don't know why it becomes such a problem given all of the amazing designs from Fusion. I had loft transitions that worked but they just weren't right. I followed a few tutorials and it seemed like it was working with spline rails and patches but eventually fell apart. I wish I could get more info from Fusion when errors occur.

I will look at the other posts and will eventually get a file uploaded here. I really appreciate the help.

Re: Need help with patches and stitching

jonavark — Fri, 15 Aug 2025 22:48:58 GMT

I've uploaded the file .

My main questions are:

On the head transition... did I do that correctly? Should the seams disappear?

I had some trouble with a toolpath for that area so I assumed I had mucked it up somehow.

On the heel transition, same questions. But I think I know where I messed up on the top of the neck, attempting to patch with one patch but the center line points are on the neck and the heel.

I don't want anyone to fix it for me but I would love some insight as to what I've done wrong. I will go look at the other posts here regarding this. I've seen so much of this over the past month I am kind of fried, which is why I had to reach out here.

Thank You to anyone who takes a look.

Re: Need help with patches and stitching

anneprom_service — Sat, 16 Aug 2025 11:39:28 GMT

thanks

Re: Need help with patches and stitching

davebYYPCU — Tue, 19 Aug 2025 01:49:37 GMT

Without doing it for you, you should consider the end result needing to be smooth(ish) transitions that accord to the design intent.

Most of your problem areas are as sharp corners, and intersecting curves that are not tangent,

Top - two intersections, only one pair are tangent. Internal curve too many arcs.

Bottom, both radii are not tangent to the straight line.

Panel 1,2,3 should not need intermediate panels here.

This sharp corner (black) point - transitioning a flat plate to the fret point, can do with a curve to smooth it (otherwise a triangle) out.

Patching with tangency, gets a closer result, but the sketches could do with a curved transition. (red curves).

A few clues to work with.

Might help....

Re: Need help with patches and stitching

jonavark — Tue, 19 Aug 2025 20:06:30 GMT

hmmm

I responded to this last night but I don't see it today.

Image 1:

I tried by best to constrain those two cuves but I am up against the outer profile of the head and I couldn't firugre out how to constrain without distorting those lines.

Image 2:

The extra panels come from the curves for the volute mentioned above. My main question here was whether the transition curves were ok. I don't _think_ those extra panels affected them but I also wish they weren't there.

Image 3:

Again I am constrained but the body design and the neck pocket shape. The changes you suggest would likely undercut the neck at the top of the neck pocket.

Can I ask if seams should disappear after a stitch? I couldn't find out if that was always part of a successful stitch or not.

I am an amateur for sure and I really appreciate you taking the time to look into this.

Thanks!

Re: Need help with patches and stitching

davebYYPCU — Wed, 20 Aug 2025 21:34:42 GMT

Pic 3, you really going to have a sharp edge on the guitar body - there?
Keep the corner point and maybe change my black curve to a spline for the suggested result.

To a degree the underside of the neck is decorative and slight change not permitted? You had 2 versions in the sketches.

Display edges or not is a setting - yes a tangent seam will not show, when using Shaded.

Might help….

Re: Need help with patches and stitching

jonavark — Wed, 20 Aug 2025 21:56:33 GMT

Yes. That is the body edge the neck heel has to conform to. Thanks for the info on the seams.

I have to assume then that the stitching actually failed?

I am a little confused by the result I am getting.

Thank you!

Re: Need help with patches and stitching

davebYYPCU — Thu, 21 Aug 2025 00:59:57 GMT

There was a stitch error but going back in the timeline fixed it.

Visible Edges / Shaded.

Not sure what parts you're not happy with, given the design restrictions.

Might help...

Re: Need help with patches and stitching

jonavark — Thu, 21 Aug 2025 22:19:29 GMT

Yes. I did leave that error in the timeline. Apologies. I wasn't using that part of the timeline. My concern is that even after stitching the bodies list still shows 5 bodies. I found this problem while trying to create toolpaths