Relief, Forms and Die Symbols for Sheet Metal

[Dan_Harlan]

I have Googled extensively and have not found any references to any drawing symbols for use in specifying sheet metal operations. Creo has the symbols for indicating bend direction and angle, but things like bend relief, forms, puches or dies can only be defined by detailing.

Does anyone know if their are standard or even examples of symbols used to indicate things like Relief types (Obround tangent, Square w/ depth, etc)? What about anything other than a note when a stamping operation uses a known form for something like a louver? (I would expect to have to put the part number of the form/die/punch into the symbol)?

[TomD.inPDX]

Most of this type of operations is buried in the shop process for making the part. Everyone's tool catalog is different and different for every machine. I think that those who want to capture this with Creo would have to develop the catalog pretty much on their own. Punch directions and sheet-up orientations, nesting and restrike information is completely out of my vision when I design sheetmetal. I don't even dare commit to bend factors since they are not my responsibility. A lot of this is trial and error on the prototype and when they lock in the "formula", a good shop locks it into their process as well. When the shop is changed, the process starts all over again.

There have been a lot of great tools available for ages in the sheetmetal shops. I know that if I delivered a good wireframe model from Cadkey, the shop had software that could reliably unfold it and never needed a print. This was 2 decades ago. I suspect that even the current manufacturing extension for Creo lacks a lot of built-in functionality that sheetmetal shops have already developed..

[Dan_Harlan]

Thanks Antonius.

I'm familiar with all that as we have a sheet metal shop in house and I'm actually looking from their perspective as opposed to from the design side. Part of this is so we can document our process so that our various locations change interchange work as needed and not have to re-develop processes etc.

Bends have a simple symbol in Creo, though we're going ot need to define more than just the bend line and angle (we will end up needed brake type, held/fixed side, tool radius, tonnage etc). What I was hoping was something similar to the the AWS weld symbols.

[TomD.inPDX]

Is that kind of standard even available for this industry?

[BrianMartin]

I'm not sure I've ever seen the kind of symbols Dan is asking about. But if anyone finds them, I'd be happy to assist in creating a new Creo library for public use so we could all share them. This would be similar to surface finish or weld symbols.

Also, if there are features or functions available in specialized sheetmetal software (or in competing products like SolidWorks or NX), let's document them. I'll take them to the next PTC Technical Committee meeting in January and get them in front of PTC developers. In my opinion, Creo sheetmetal has been lagging behind SolidWorks for quite some time. We routinely have shop personnel asking why Creo can't do some of the advanced sheet metal healing, unbending, and measurements available in SolidWorks.

I'd like to identify any functionality gaps and lobby PTC to work on closing them.

Thanks!

-Brian

[pshepherdson]

Hi Brian,

While your'e at it, in regards to a Sheet metal wish list. Can you also bring up flat / flange mating? What I mean is, I have my planar flat (1st wall). I add a flange (or flat), then add another and another (not using chained edge, for whatever reason).

My 1st bend is the full length of the chosen edge. My 2nd bend is the length of the edge, from the inside bend radius, & so on. So, the 1st bent up vertical edge is overlappign the 2nd bent vertical edge, startign at the radius of teh 1st bend, and so on...

I find it a pain to try & manipulate these two edges, because I don't want overllaping edges, but for them to come together, inside edge to inside edge, nice, neat & uniform. I can also then run a quick fillet weld if need to to dress the corner. (you would figure 2 shots of "edge extend" would do this, but sadly, no.) It's very hard to switch / modify the edge overlap after the flange / flat is made.

It seems the only way to do this (easily!) in Creo is to start with a solid, then convert & shell to get nice, mating edges. Although rare, there are times when you can't really start with a solid block. Or, worst, when you need to add a flange to a part after the fact...

As I recall, Inventor had an edge command, quick & simple. Pick edge one, pick edge two, define how the edges are to meet, what gap, overlap, extension, etc.. and what type of releif you want.. OK, done. All in a nice little dialog box.

2nd wish (or gripe) is if I have a bend on a flat, and is not 90° to an edge, I get this littel point, becasue the bend radius has ripped from the edge, because it's not 90°. Why can't teh bend radius roll along the edge?

Paul

[Dan_Harlan]

So, what I've found out is that their is no such industry standard. Carol Tower who is the librarian for SME (Society of Manufacturing Engineers) help me out in this regard. The only reference she could find was JIS B 0122, though very promising by title, turned out to not be applicable (http://translate.google.com/translate?hl=en&sl=ja&u=http://kikakurui.com/b0/B0122-1978-01.html&prev=search)

Nobody even seems to know which organization might make sense to be such an "owner". Though I've been re-routed to other projects at the moment, I will keep looking and will let you know if/when I move forward.

[jwindcoach]

Well, today I went hunting for some punches and form on the web.  Found almost nothing.

I'm not looking for a standard's spec'ed punches and forms, rather I'm looking for exsisting ones that would get me closer to what I can modify for my needs. 

For example, PTC has a neat video on a gusset tool.  BUT, they do not provide the CAD file for this.  It would be great to take the CAD file, tweak it to my use for the shop floor and be happy.  BUT, rarely do these things in CREO-Pro-E are to be found vs. other CAD packages.

I would rather spend my day making parts physically from the CAD data vs. spending my entire day trying to 3D CAD model things up.  CAD is suppose to be fast ... eh?

[jwindcoach]

BTW, here is the link to that neat PTC video with the gusset.

https://learningexchange.ptc.com/tutorial/444/punch-form-features

[jwindcoach]

About 3 years and still not one reply.  wild.

[Pettersson]

If you're looking for the CAD part used in the video, it looks like it's part of a PTC University Sheetmetal class, so if you have access to PTCU you should be able to download the part. Though I'm sure it takes less than three years to model it from scratch ...