guran Posted May 27, 2013 Share Posted May 27, 2013 If you have a steel plate bent in several directions and with non-perpendicular ends, designed in 3D Auto Cad. For example, the plate can be curved with a certain radius in the vertical direction and another horizontally. How would you, or what software would you use, to get the plate flattened to the exact measurements of how it should be cut. Quote Link to comment Share on other sites More sharing options...
tzframpton Posted May 27, 2013 Share Posted May 27, 2013 AutoCAD cannot do this OOTB. There may be a 3rd party that can accomplish this automatically. I do know Autodesk Inventor has sheet metal tools that will generate a flat pattern, including the bend tolerances, etc. Quote Link to comment Share on other sites More sharing options...
JD Mather Posted May 27, 2013 Share Posted May 27, 2013 Can you attach the dwg file here? Quote Link to comment Share on other sites More sharing options...
guran Posted May 28, 2013 Author Share Posted May 28, 2013 Sorry, I have nothing to show. This is something we planned to do and wondered how to do it. We have solved these problems in 2D before but it should be possible to get these measurements directly from a 3D drawing. Quote Link to comment Share on other sites More sharing options...
JD Mather Posted May 28, 2013 Share Posted May 28, 2013 Sorry, I have nothing to show. This is something we planned to do and wondered how to do it. It is not possible to answer your question if you have nothing to show. The first step would be to create 3D model that represents something typical of what you need. What is the manufacturing process used to produce the parts? (Brake press? Die press? Progressive strip?) Quote Link to comment Share on other sites More sharing options...
tonyj Posted May 30, 2013 Share Posted May 30, 2013 (edited) JD, have one for you. Its a sheet part similar to the one mentioned above. I was asked to create the part from a 2d drawing and put in folding lines for the press. Now there was no problem creating the part in autocad. But when it came to figuring out the fold lines, I just tried and tried for about 6 hours and then gave up. (which is something I don't normally do) I can create ordinary sheet metal parts in auto cad and create a dxf/2d drawing with fold lines that are identical to the ones created in pro-e, which some of the other lads in the office use. Say for example we use the same part and we both flatten it and impose one over the other, they are identical. But this particular part is a probleym. One of the pro-e lads said that he would do it in pro-e, but he could not do it either. Its a propeller blade. That was about three months ago and I didn' t hear any more about it since. I will pull out the 2d drawing tomorrow and post it here if you are interested in taking a look at it and letting me know your thoughts on it. Sorry about my typing, I'm on an android phone. Edited May 30, 2013 by tonyj Quote Link to comment Share on other sites More sharing options...
neophoible Posted May 31, 2013 Share Posted May 31, 2013 Sorry, I have nothing to show. This is something we planned to do and wondered how to do it. We have solved these problems in 2D before but it should be possible to get these measurements directly from a 3D drawing.Perhaps you at least have some sort of image of the final product, or something equivalent from the past that was solved 2D? Quote Link to comment Share on other sites More sharing options...
JD Mather Posted May 31, 2013 Share Posted May 31, 2013 JD, ... I can create ordinary sheet metal parts in ..... Sheet metal stretches on the outside of a bend and compresses on the inside of a bend (bend allowance) resulting is a flat pattern and bend locations not where you might expect. Bend allowance is dependent on 4 variables, material, thickness, bend radius, and bend angle (and perhaps a fifth - grain direction). Programs like Inventor and Pro/E can calculate the bend allowance for you, but AutoCAD cannot. The usual process is to model in the finished form as you know the finished dimensions you need. Then modern programs with sheet metal tools will create the flat pattern for you calculating the bend allowance. Quote Link to comment Share on other sites More sharing options...
guran Posted May 31, 2013 Author Share Posted May 31, 2013 What I'm after is just not that complicated, it can be as simple as in this image. I would like to be able click on it and get it flattened. Quote Link to comment Share on other sites More sharing options...
ReMark Posted May 31, 2013 Share Posted May 31, 2013 You can flatten it in AutoCAD alright (via the FLATTEN command) but you won't get the result you are looking for. Quote Link to comment Share on other sites More sharing options...
JD Mather Posted May 31, 2013 Share Posted May 31, 2013 What I'm after is just not that complicated, it can be as simple as in this image. I would like to be able click on it and get it flattened. Are you a student? If so, you can download Autodesk Inventor for free from http://www.autodesk.com/edcommunity or download 30-day trial or attach your dwg file here and indicate the thickness (inside, outside or midplane) and material. Quote Link to comment Share on other sites More sharing options...
tonyj Posted June 1, 2013 Share Posted June 1, 2013 (edited) What I'm after is just not that complicated, it can be as simple as in this image. I would like to be able click on it and get it flattened.[ATTACH=CONFIG]42173[/ATTACH] What is the thickness of the material? What type of material is it? What is the radius of the arcs? Where are the arcs in relation to the material? ie. are the arcs that you have drawn, to the inside of the finished plate, or the outside, or are they at some point in between? When you answer those questions your problem can be solved in autocad.? Ps. You can never get autocad to 'click on it' and give you the result you want. How-ever with a few elementary lessons in metal rolling and folding you can create accurate flatstates in autocad. This normally takes about 6 times longer than it takes in pro-e or inventer. Average sheet metal parts for conveyors, hoppers, chutes and guards in autocad after been modelled, in solids, can take 2 to 8 minutes to flatten out per part, with fold lines, in autocad. Not only that, but you can create flat states in autocad more accurate than pro-e or inventer can and I can explain why that is. Edited June 1, 2013 by tonyj Quote Link to comment Share on other sites More sharing options...
JD Mather Posted June 1, 2013 Share Posted June 1, 2013 .... but you can create flat states in autocad more accurate than pro-e or inventer can and I can explain why that is. Start explaining. Quote Link to comment Share on other sites More sharing options...
tzframpton Posted June 2, 2013 Share Posted June 2, 2013 Start explaining. +1. I'd love to hear this one too. Quote Link to comment Share on other sites More sharing options...
tonyj Posted June 2, 2013 Share Posted June 2, 2013 Start explaining. Right. I work in autocad and when i'm creating mild steel sheet metal parts I use a k-factor of .44 We have three engineers in our company using pro-e. Now pro-e has got a y-factor (which is unique to pro-e) and the y-factor is : Y-factor=k-factor(pi/2) and by default the y-factor in pro-e is set to .5 and therefore leaves the k-factor set at about .3 Now anybody using pro-e that is not aware of this and working in mild steel is using the wrong k-factor. BTW the k-factor for mild steel should be .44 and I have tested this on our press and found it to be suitable to the machine. Most people using pro-e or inventor are grads, and you can tell them nothing. Quote Link to comment Share on other sites More sharing options...
JD Mather Posted June 2, 2013 Share Posted June 2, 2013 You still haven't explained how your AutoCAD solution can be more correct than Pro/E or Inventor. Can't the bend allowance be edited in Pro/E or Inventor. Can't Inventor use a Bend Table based on data from actual production machine (I don't know Pro/E sheetmetal) in place of general k-factor formula? Quote Link to comment Share on other sites More sharing options...
tonyj Posted June 2, 2013 Share Posted June 2, 2013 I'll put it to you this way. I know three design engineers using pro-e and 100% of them are not not creating sheet metal parts correctly, who is to blame for that? I am creating sheet metal parts more accurately in autocad than they are in pro-e. Quote Link to comment Share on other sites More sharing options...
tzframpton Posted June 2, 2013 Share Posted June 2, 2013 I am creating sheet metal parts more accurately in autocad than they are in pro-e.I assume you are doing this on a manual basis because to my knowledge there is no flat pattern tool in the OOTB AutoCAD software. I remember in my early early early CAD days when I actually used Inventor, the flat pattern tools where nice but my boss required me to use AutoCAD and manually calculate the bend tolerances. I don't know if there are discrepancies in the Inventor and Pro/E tools or not, but that's what I remember. My initial prodding for an example was directed to how AutoCAD creates flat patterns.... it sounded like you used some type of tool that would automatically produce flat patterns or vice versa. Quote Link to comment Share on other sites More sharing options...
neophoible Posted June 2, 2013 Share Posted June 2, 2013 You still haven't explained how your AutoCAD solution can be more correct than Pro/E or Inventor. Can't the bend allowance be edited in Pro/E or Inventor.Can't Inventor use a Bend Table based on data from actual production machine (I don't know Pro/E sheetmetal) in place of general k-factor formula? Right. I work in autocad and when i'm creating mild steel sheet metal parts I use a k-factor of .44 We have three engineers in our company using pro-e. Now pro-e has got a y-factor (which is unique to pro-e) and the y-factor is :Y-factor=k-factor(pi/2) and by default the y-factor in pro-e is set to .5 and therefore leaves the k-factor set at about .3 Now anybody using pro-e that is not aware of this and working in mild steel is using the wrong k-factor. BTW the k-factor for mild steel should be .44 and I have tested this on our press and found it to be suitable to the machine. Most people using pro-e or inventor are grads, and you can tell them nothing. I'll put it to you this way. I know three design engineers using pro-e and 100% of them are not not creating sheet metal parts correctly, who is to blame for that? I am creating sheet metal parts more accurately in autocad than they are in pro-e. I'd say he explained what he meant, it just doesn't have to be quite the overarching problem it sounded like initially. The problem sounds more like trusting the computer too much. GIGO. Maybe the factor could be adjusted, but you'd have to have the expertise/experience to be able to do so, and to realize that what you currently have isn't right. If you only go with the defaults, then it sounds like tonyj is making his point quite clearly. "The proof of the pudding is in the eating!" but if you never try the pudding, then 'My recipe is clearly the superior.' Add 'IMAO' to finish that one. I think we all know of plenty of people who will argue to the death (yours, if they can arrange it!) based on supposed superiority rather than fact. Quote Link to comment Share on other sites More sharing options...
tonyj Posted June 2, 2013 Share Posted June 2, 2013 Just to be clear. You can adjust the k-factor in pro-e and the y-factor gets adjusted in relation to that. The main point is that, unless a person using pro-e has a decent understanding of sheet metal bending they will be using the wrong k-factor. So I would say that there is a high percentage of pro-e users out there doing drawings of metal parts that are not correct, and I can produce these more accurately in AutoCAD than them in pro-e. Stykface, I am doing this on a manual basis. I have done metal parts in pro-e (with the k-factor set correctly) made the flatstate and then imported the model into AutoCAD and made a separate flatstate in AutoCAD. The results are identical. Quote Link to comment Share on other sites More sharing options...
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