AnsweredAssumed Answered

How to use SW 2D drawing to form parts

Question asked by Frederick Wolf on Jun 6, 2009
Latest reply on Jun 10, 2009 by Frederick Wolf

Like • Show 0 Likes0
Comment • 10

Hello

I have a sheetmetal forming company, and recently several customers have provided me with SW 2 D drawings that only provide dimensions to some feature in the bend (maybe center of bend radius), angle of bend, direction of bend, and radius of bend. I have to go back and ask them to dimension the formed drawing in x,y, and angles.

This is time consuming and I suspect if I can learn how to use these drawings in setting up the backgage dimensions that my setups will be much quicker.

What I need is information on how to use the SW 2D drawings to actually make real parts. Can anyone help or point me to a resource that can help?

Thanks much

Frederick

No one else has this question

Outcomes

10 Replies

Kenneth Barrentine Jun 6, 2009 6:23 PM
Mark Correct
Correct Answer
are you saying all they give you is a flat-pattern drawing?
if yes, just give them a flat part and enjoy the reaction!

is the customer responsible for the K or bend deductions?
if not they shouldn't be giving you any information pertaining to the flat-pattern development. after all, as a sheetmetal forming company that's your job.

tell the customer you need a drawing that is dimensioned in the formed state.
after all, that's what they really want right?

another option, ask for the model (part (.sldprt)).
Like • Show 0 Likes0
Actions
- Anna Wood @ Kenneth Barrentine on Jun 6, 2009 10:16 PM
  Mark Correct
  Correct Answer
  Frederick,
  
  I agree with Ken. If we recieved a drawing like you describe we would be asking our customer for dimensioned and toleranced forms of the final part. We would politely tell them we do not use their flat patterns and will develop our own to meet their final formed part requirements.
  
  What exactly is the file type your customer sent you? Is it a pdf, EDrawing, or actual SolidWorks files.
  
  Also there are multiple ways SW can set up the bend lines. Was the drawing created using Bend Deduction or Bend Allowance? What is being shown on the drawing.
  
  You can figure this out for yourself if you had the actual SolidWorks part files and the SolidWorks drawing files.
  
  Do you have SolidWorks installed on your computers so you could reverse engineer their part requirements?
  
  Cheers,
  Like • Show 0 Likes0
  Actions
  - Frederick Wolf @ Anna Wood on Jun 6, 2009 11:27 PM
    Mark Correct
    Correct Answer
    Anna
    
    Often my customers only send me a fax, I am lucky when I get a pdf. I have SW 2007 and went through the sheetmetal tutorial this afternoon. From what I can see, if the customer does not input the correct parameters, such as material, gage, and K factor, the flat drawing is not going to be very accurate. It looks as though I need to train my customers that although SW can do flats from geometry, they will need to provide me with a fully dimensioned and toleranced print.
    
    Interestingly enough, I have prototype development companies that provide me with solids only and have agreed on a set of tolerances (usually +/- .005" and +/- 0.5 degrees) so I can easily and quickly provide them with parts.
    Like • Show 0 Likes0
    Actions
    - Anna Wood @ Frederick Wolf on Jun 7, 2009 1:38 AM
      Mark Correct
      Correct Answer
      Frederick,
      
      We never, ever trust a customer flat pattern. The reason you state is why, most likely they do not input the correct bend parameters for k-factor, bend deductions, etc. Trust but Verify.... :-)
      
      We can work from solids only and have vendors that can handle that also. But we always make sure to provide or get enough info to do the job, like you, with agreed upon tolerances, etc.
      
      Looks like you have some customer education to do. We seem to do that pretty regularly with our customers also.
      
      I spent quite a bit of time this week remodeling some parts to send back to a customer. Wanted to show them what they were really going to get for sheet metal parts. Their models had no basis in metal reality.
      
      Most all of our customers are very appreciative to get manufacturing input on what really can be manufactured. Or how to make a few changes to get the functionality they desire at lower cost, with quicker delivery, by using more conventional manufacturing techniques.
      
      Cheers,
      Like • Show 0 Likes0
      Actions
    - Carter West @ Frederick Wolf on Jun 8, 2009 1:40 PM
      Mark Correct
      Correct Answer
      
      Frederick Wolf wrote:
      
      ...It looks as though I need to train my customers that although SW can do flats from geometry, they will need to provide me with a fully dimensioned and toleranced print.
      
      Absolutely correct. Fredrick, my brothers and I closed our precision sheet metal shop of over 30 years in 2004. We went through a period which customers (Varian) sent us flat patterns and what our tooling did to their calculations never ever came out right. We had to institute a policy of making parts only from a fully dimensioned draft with front, side, and top views. ISO nice, but not required. On some occasions we would need a sectional view as well.
      
      Without the three view dimensioned drawing, you will never win the argument about a reject batch of parts.
      
      Like • Show 0 Likes0
      Actions
      - Frederick Wolf @ Carter West on Jun 10, 2009 12:24 PM
        Mark Correct
        Correct Answer
        Do I have this correct? From a sheetmetal manufacturer's point of view, designers using the sheetmetal feature of SW are usually wasting their time by creating flat patterns for the following reasons:
        
        1. The materials chosen may not exactly match the materials used due to lot to lot variation.
        2. The choice of Bend allowance or bend deduction will ultimately be done by the person making the part.
        3. K factor, enough said.
        4. The form tools called out in SW may not be the tools that the manufacturer will use.
        5. The designer would be much better served by spending their time dimensioning the formed part as that is what we will work from regardless.
        Like • Show 0 Likes0
        Actions
        Anna Wood @ Frederick Wolf on Jun 10, 2009 2:35 PM
        Mark Correct
        Correct Answer
        
        Frederick Wolf wrote:
        
        Do I have this correct? From a sheetmetal manufacturer's point of view, designers using the sheetmetal feature of SW are usually wasting their time by creating flat patterns for the following reasons:
        
        1. The materials chosen may not exactly match the materials used due to lot to lot variation.
        
        2. The choice of Bend allowance or bend deduction will ultimately be done by the person making the part.
        
        3. K factor, enough said.
        
        4. The form tools called out in SW may not be the tools that the manufacturer will use.
        
        5. The designer would be much better served by spending their time dimensioning the formed part as that is what we will work from regardless.
        
        Frederick,
        
        That sounds about right. One caveat being if you are the designer that is designing the parts for your own manufacturing shop. If you are doing that, you will have all the info above and can design your parts accordingly based on the tools, materials and shop practices of your manufacturing environment.
        
        If not that flat pattern you create for some other manufacturer to use is a waste of time. It is only good to give you an approximate idea of material usage needed.
        
        Cheers,
        
        Like • Show 0 Likes0
        Actions
        Devon Sowell @ Anna Wood on Jun 10, 2009 2:40 PM
        Mark Correct
        Correct Answer
        Hello Frederick-
        
        Anna is correct.
        
        I ran into this situation 2 years ago: a company I was designing for wanted to inspect both the flat pattern and the bent part. First, I asked them why? I don't care about the flat pattern, only the finished bent part, inspect that one only. They were using different vendors and tweaking the material each run too.
        
        It took them a few weeks of wasted time and they finally agreed to only inspect the bent part.
        Like • Show 0 Likes0
        Actions
        Frederick Wolf @ Devon Sowell on Jun 10, 2009 11:06 PM
        Mark Correct
        Correct Answer
        Certainly in the case of my company, the form tools are simply not available anywhere. We form very small to small dimension thin gage parts and all of my tooling has been modified to work with these small parts. I have now prepared a letter with my suggestions for customers who are using CAD to create parts and I will be using the information you folks have been so kind to share with me.
        
        Happy trails
        Like • Show 0 Likes0
        Actions
Josh Brady Jun 10, 2009 12:35 PM
Mark Correct
Correct Answer
I would agree with those statements as well, Frederick. If the shop making the drawing and the shop manufacturing the part are the same, the sheet metal flat pattern could be useful as long as the person who knows the process can work with the CAD admin to get the all the data tables, etc. set up correctly. Otherwise, tell the fabricator what you want him to give you, not how to do his job.
Like • Show 0 Likes0
Actions

How to use SW 2D drawing to form parts

Outcomes

Related Content

Recommended Content