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@david pierce wrote:
The drawing is excellant and very professional looking. When drawing a mechanical part it is good to keep in mind that everything in the drawing has to be made by a machinist with their available tools. For example, if a piece of 1/4″ crs has a square hole in the middle, it is less expensive and time consuming to require that the hole has rounded corners if the square hole is to be milled. Square ID corners are easier to draw but more time consuming to machine. With outside corners the opposite is true. Square outside corners are less time consuming than rounded outside corners. Tight tolerances are also expensive. If a drilled hole is good enough to make the part function properly then it should not be toleranced to .0001 inches. Different tolerances require different machining processes in order to produce a part.
Thanks david. When we did contract design documnts we always listened to those who did the work in the field as sometimes they could do something better and cheaper than what the engineer of record had specified in the design. So… I do understand that I have a lot to learn. Yet, this kind of commentary is super helpful for me and I really appreciate it. I’ll try to remember all of these points as I go.
@david pierce wrote:
If you get the HF mill and begin to make the part that you drew, you will begin to rethink the design. You will ask yourself: How do I make this angle? Do I machine it out of a solid block of material? Do I take a piece of flat stock and bend it? Do I fabricate it from two pieces of flat stock? All of these issues affect the cost of the part. The only way I know to get a feel for this is to jump in with both feet and cut some metal.
I thought about if I had that HF mill, how I could mill the bottom of that plate – or, how would I make the angled edges that fit on top of the lathe bed bar.
Regarding the grade of steel… is what I have shown even in the ball park? If you were making this part, what grade of steel would you use?
I really appreciate every you post.