topic Re: Sheet Metal Unfold Rule Error after modifying in Inventor Forum

Sheet Metal Unfold Rule Error after modifying

RAndersonB5C66 — Mon, 20 Jan 2025 16:12:32 GMT

I have an unfold rule made using an imported bend table that works according to a previous shop managers unfold parameters. Now we're going back to the original way and so I tried changing the unfold method from "bend table" to "custom equation" and adding in those parameters as seen in attachment "error-1". Although, when I try saving that error pops up and haven't found a related article on the topic. The bend table method has worked just fine, so it can't be referencing that. Only does this error when I try adding another unfold method to the existing rule. Would greatly appreciate the help!

Secondly, we're receiving customer parts from canada so they're using metric settings/inputs for everything and tucked corners instead of corner-corner it should be (per our bid). Trying to find the easiest way to get the custom equation into their models and adjust without it messing up all their sketches and flanges created, but finding it hard to do. I tried testing the bend table on their part and it still wasn't matching the flat layout dims it should have with a 90 & 45 degree flange like it does with the same part if I make from scratch. Will I need a metric version of the equation in attachment, or does going to "document settings" in their part file and changing units to inches not solve this?

Re: Sheet Metal Unfold Rule Error after modifying

hollypapp65 — Mon, 20 Jan 2025 17:48:04 GMT

@RAndersonB5C66 wrote:
Will I need a metric version of the equation in attachment, or does going to "document settings" in their part file and changing units to inches not solve this?

Why would bend allowance be different in metric and imperial?

Why are you using custom equation? What equations are you using?

If bend table works, why you don't want to use it?

Re: Sheet Metal Unfold Rule Error after modifying

RAndersonB5C66 — Mon, 20 Jan 2025 19:02:40 GMT

1) Because metric conversion of .085in is a different number? So I'm asking if it needs to be converted to that number for the equation on a metric .ipt file from customer, or if changing units (mm to inches) in document settings takes care of that, since there's no readily available manual for sheet metal settings I can dive into and figure this out myself. Another factor on the error I'm wondering is the cause; if it won't allow an equation method put in if there's already an imported bend table for an unfold rule, but idk why inventor would not separate from each other if it's a different method to toggle between.

2) Why not use the equation? It's simpler/faster to create for the bend allowance we're using within a given range of degrees as seen in the prior attachment included.

3) Bend table represented the prior method with varying growths at every degree, so like stated before it's no longer relevant to the correct bend deductions for angles.

Re: Sheet Metal Unfold Rule Error after modifying

hollypapp65 — Mon, 20 Jan 2025 18:54:11 GMT

1) Inventor use mm for all internal calculation.

0.085in metric conversion? 1in =25.4mm 1mm=0.039in

I'm in Canada. Using imperial and metric. k-factor is the same for both. Bend allowance is the same also, in proper unit.

2) Since IV didn't accept your equation, there is something wrong with your equation.

Don't know what's since I've never used equation.

Can't fix different corner miter with bend allowance.

Got a model we can look at?

Re: Sheet Metal Unfold Rule Error after modifying

RAndersonB5C66 — Mon, 20 Jan 2025 19:29:36 GMT

1) I was asking if it needed to be converted not how to convert between the two lol

2) Nothing wrong with equation, I referenced it from a prior employer's input and that never had an issue. Also, I ended up just creating a new style for the unfold rule and input the equation there and it works so must be something to do with trying to input a second unfold method to a style using a bend table.

3) Sorry, only willing to send files to one of the "autodesk elites" on here that work for autodesk.

4) Based on the results from messing around with adjusting customer's files, best I can hope for is adjusting the unfold rule to my new equation method and adjust all the notching in AutoCAD. All of the sketches are referenced to profiles that used a tucked corner settings, so everything gets messed up and a pain to fix. Included examples of customer's notching style vs my part made from scratch the correct way.

Re: Sheet Metal Unfold Rule Error after modifying

johnsonshiue — Tue, 21 Jan 2025 22:56:29 GMT

Hi! The error does not seem to be related to the Bend Compensation (Equation) styles. It is from one of the Bend Tables. It seems that there are duplicate rows or columns. Please share the ipt file here or send it to me directly (johnson.shiue@autodesk.com). I would like to understand the error better.

Many thanks!