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I am curious as to how many people/companies are using ProE models as the master specification for driving tooling? When this is practiced to what extent are you detailing the part? How are you meeting inspection requirements?
Our casting drawings only detail the chucking locations. Other requirements are handled in the notes such as the corner and fillet radii, draft and overall profile tolerance of the part. We still detail the machined version and other components. As for supplier prints, we import their drawing inside our titleblock and use their model that they supply to us.
Our drawings call out only critical dimensions for fit & performance. There's a blanket note in the format indicating that the 3D CAD data is the 'master', the dimensional information on the drawing is for quality control.
Thanks for the replies. The company I work for is struggling with definition of our Master Models. I just finished detail a casting that ended up with 6 sheets and approximatley 1000 dimensions. When we had our review with the supplier they could not believe what they were seeing. They said they would rather see key features dimensioned and an overall surface profile tolerance. I am trying to convince my company to start using this method instead of fully defining master models in print. This will be a large battle and I need all the help I can get.
One thing that might help you is that you have comments from two other sources that are using the model as the master.
Another thing I forgot to mention in my eariler post and DGS's post made me think of it. We will also dimension features on the drawing that fall outside of the limits of the blanket notes.
Good luck and I hope that others add to this thread to help strengthen your case. Edited by: audctrl
We maintain the CAD database for one of our customers and they've been doing this for 7+ years (long than I've been here).
If you want to make the case, think through how many hours you (or someone) spent creating that drawing. Likely a week of your time? What does that translate into dollars? Talk to the supplier, what does it cost them to have a drawing like that? They have to pass that on to you.
Multiply that by the number of drawings you do each year. The higher ups always respond better when you talk about saving money.
One question I have about adding a surface profile tolerance. This last part that I done was pretty large. My supplier said they would expect a surface profile tolerance of somewhere around 1.9mm. My question is concerning wall thickness. In a worse case senario I could have a wall move inward on each side by 0.95mm. This would result in a thin wall but would pass a comparison check of 1.9mm. How do you preventthis thin wall condition from being a good part?
I believe there are a few factors involved one is the casting process sand, perm. mold, die cast, etc. Each method has there own characteristics like minimum wall thickness, draft and surface profile, ribs and rounds. So depending on what process we are using determines what wall thickness we should use. For instance one process may call for 4.5mm wall and a 1.6 profile while another only needs a 3.0mm wall and a 1.0 profile. Some parts can have a wrap around core where part of the inside and the outside of the part come from same part of the mold. Thus relocating your core shift to a less critical area of the part.
I understand There are different things that factor into what your wall thickness shall be. My question is how are you measuring your part to insure that your wall thickness has been met. Your laser scan comparisson is just checking for surface movement within your allowed surface profile tolerance. On our master model prints we currently do not call out a minimum wall thickness. Our prints are fully defined and the wall can be calculated by the dimensions on the sheet. I guess what all this boils down to is I think our company is only using part of this technology and wasting money on paying drafters to fully define something that someone else has spent many pain staking hours modeling. It seems that we are doing to job twice. Not only am I up aginst the design and drafting managment but also our measurments department.
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