Seeking Sheet Metal Rule (s) for paper and cardboard.

[drew]

I'm posting in hopes that someone will have or know of 'known-good' Sheet Metal Rules for use with paper, card stock , and cardboard.

Anyone here have a "Rule" or Rules that work well for a particular paper stock thickness? Where bends in real life happen as expected by the model's Rule?

If so, could you please post its name, material, and a list of the field info for it/them? (You know, the user-modifiable stuff in the editing area for a Sheet Metal Rule, like "K-Factor" and "Relief Shape"  etc, etc)

Alternately if anyone knows of some "Repository of User-created Sheet Metal Rules for Fusion360", please link me to it?

Thanks ahead if you can!

[Oswaldo.cancellara]

I'm on the same situation.

I'm trying to get in contact with autodesk support specialist to find out if they can help me to set up the material and the sheet metal rules on fusion to work properly with cardboard.

[k.j.larson]

Was this ever answered?  I too am interested.  

[TheCADWhisperer]

@k.j.larson 

What is most important to you with the finished folded design, the outside dimensions or the inside dimensions?

What is your desired bend radius?

Can you Attach an example design here.

[TheCADWhisperer]

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@k.j.larson wrote:

Was this ever answered?  I too am interested.  

---

@k.j.larson 

Where did you go?

Abandoned efforts are why questions go unanswered.

[mango.freund]

https://youtu.be/1aDN44__L9E

[mango.freund]

https://youtu.be/V5_ZTZ_DTCc

[drew]

Hi, 

I never got a good answer. 

Cheers.

[TheCADWhisperer]

@drew 

Are you now ready to pursue this question to a solution?

[k.j.larson]

Thank you for your support, and for posting the video link.  That answered many of my questions/needs.  I apologize for taking a few days to get back to you.  I am very interested in the respective answers, but we just purchased a new laser and have been busy working to set it up.  Alas, there are only so many hours in the day.  :-).  Again, thank you.  

[k.j.larson]

CADWhisperer:  thank you as well.  While it may seem like I abandoned you and disregarded/disrespected the time you were taking to try and assist, that was not the case.  Sometimes life simply gets in the way of the fun stuff.  But all has worked out, the video links have set me down the path I needed.  Again, tks.  

[drew]

@TheCADWhisperer 

It's been a year since I posted that, and I long ago finished the project and moved on with life... But yeah I guess "I'm ready" (A very weeird thing to ask, btw - sounds confrontational and snarky to my reading ears)

So-

Yeah you can take a sheet metal rule and hack it. It will work for a lot of tasks if you're not fussy. That's what I did last year.

BUT: The sheet metal rules as I understand them do not allow for a common and important behaviour that cardstock and cardboard have: Delamination and sheet shearing at the bending site.  Metal will stretch, and compress. Paper? Not so much, eh? They just don't fold the same way.

Take a good close look at the inside of a greeting card - look at the fold. There's most likely a very defined 'hump'  along the fold where you'd think it would be an inside corner. That's because the surface of the cardstock tore loose from its core because the fold was attempting to compress that outer layer, it wouldn't compress, so it deflected OUT. And because that bulge introduces more layers of paper (right AT the fold site) and it distorts a clean crisp angle. 

This bulging/delamination also happens with cardboard- which behaves differently depending on which way you are folding it- along the core or across the core. Also, cardboard comes in many variants, some strong and some weak. They don't bend alike either.

So my general thought was/is that like the metalworking people who readily share their proven setups for bending metals of many types, the crafters and scale modelers should have a library of proven cardstock/cardboard folding setups that are 'known-good'. (Some of us still actually make small things by hand without a 3D printer.)

So yeah - cheers to you for chiming in on a dead post!  It would be good to sweep the barn every few years.

If you think I should, I'll mark your video post as the answer - will that help? Just say so.

[adhyan1991]

I am using the sheet metal tools of fusion 360 (and in the linkstage 3 branch of Freicad) with non-metaphorical materials such as cardstock, chipboard and corrugated cardboard. While I have not received any official repository for non-metal sheet metal rules, I can share some personal setups that give realistic results, especially for folding cardboard and heavy paper:

📏 My custom rules for 4 mm corrugated cardboard:

• Ingredients: Custom - "Corrugated Cardboard"
• K-factor: 0.70 (cardboard crush instead of stretch, so it folds better)
• Fold radius: 0.5 mm (during any lower cause model failures)
• Relief Size: Strait (does not round the real life tear/crushed well)
• Relief depth: 2.0 mm
• Relief Width: 1.0 mm

For Cardstock (about 300 GSM):

• Ke-Factor: 0.5
• Fold Radius: 0.3 mm

A small trick that I use, doing a test, after every major convenience, quickly catch problems quickly - folds or geometry often to throw results, especially with coarse paper types.

Would also like to see a common rule library for these materials - maybe we should start a one?