Is flatten view must when making a drawing for sheet metal part? Because in this drawing there is no flatten view.
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For manufacturing of the part I would say yes. In the flatten state it shows the proper locations of the bend lines for the press brake operators to accurately achieve your part.
Some companies will put the flattened view on the second page of the drawing.
I always show a flattened view.
todd
In such a case what will be the size of the paper? I have seen here 6 views are paced in B size paper.
We use paper size B because we do not have a big plotter. So the biggest paper we use is 11" x 17". If you have access to a plotter that will plot bigger drawings, a bigger paper size would definitely help with a better detailed drawing.
Most of our stuff is A size, which is why I often put the flat pattern on page 2.
Depending on the part, it is usually 3 views, isometric, flat pattern.
(Simple parts might be one or two view, no iso, and if it doesn't get bent, it doesn't need a flat pattern.)
To obtain the Flattened view you must specify it in the "orientation" menu...
If Sheet Metal part is intended for manufacturing I think so two views are enough 1)isometric view and 2)flatten view. What is in common place?
It really is your preference. If you think the press brake operator can do the job properly with those 2 views then great but I usually do most all of my parts like this, or similar, depending on how complicated the part is. Of course with dimensions, just threw this together for a visual.
Maha Nadarasa wrote:
If Sheet Metal part is intended for manufacturing I think so two views are enough 1)isometric view and 2)flatten view. What is in common place?
No.
The customer (contract) pays for the dimensions of the finished folded model.
Because of bend allowance (material stretches on outside of bend and compresses on inside of bend) the flat pattern could be considered "reference" geometry - not the contract geometry.
Bend allowance can depend on material, bend radius, bend angle, thickness and the machine tooling used.
We never use a flattened view because different suppliers use different methods and "K" factors to manufacture the sheet metal piece. What we show on the drawing is enough views to properly define the piece because in the end, that's what we're buying.
Steve C
I work at a shop where your place of employment sends stuff to, a job shop. I redraw your drawings with the proper K factors we use for production of the part. This is the way, I myself send a drawing to my guys out in the shop. Because we are a "metal fabrication shop" the press brake guys ask for as much detail on a drawing as possible to ensure the part made as close to the customers specifactions as possible.
This is why I use the default K factor on designs. The problem is, as you've seen, we go to many places for our work and sometime even have the flats (with a few bends) sent in and we do the final bending. Kind of makes it tough but in the end we get a good part.
Steve C
Depends on the vendor (if known) some vendors/ fabricators prefer to calculate the bend tolerances themselves to suit their machinery, making your lay-flat redundant. If you supply a lay-flat, then you're responsible for the outcome/revisions. If you supply the formed part, the vendor is more likely to do the work to deliver the formed part you specified.
Actually, I would be inclined to say that unless you're working with a known vendor and you're set-up to use their bend tolerances, and you have a list of their tools, I would leave the lay-flat off the drawing.
EDIT,
Obviously supply them with a parasolid of the formed part.
Exactly - I can show the flat pattern because:
1) We do all of the forming in house
2) They know that the formed view dimensions are the important ones, flat pattern is for reference and only has bounding dimensions for rough material usage.
