to see some more active CAM stuff…because I’m selfish. Somehow I was moved from my design only position to something closer to “Continuous improvement”. My first big continuous improvement is to attempt to reorganizing the wreak of a programming system we have here to something more resembling what a company with multiple millions in sales should look like rather than what might result from “Bob” attempting to print out a various repair parts for his remote controlled airplane in his garage.
My personal experience in CAM is pretty narrow, but I’d love to see more CAM related stuff, and in particular what CAD people can do to make CAM work better and give better results. Maybe you could start out by writing something about that? What sorts of things do CAD operators do that make you want to bust a monitor over someone’s head?
Like 0.06" rad on all internal and external corners?
ALL CAD people should have a working knowledge of manufacturing prior to ever being allowed to release something to manufacture.
The list of things that “CAD” people do to make parts more difficult, more expensive or just down right impossible to make is fairly endless.
Well, then that sounds like a great place to start a great discussion. Educate some CAD users! 
I programmed and help make a part out of a solid chunk of 316SS. Hard to describe but it had .03-.06 rad essentially everywhere there was a corner. The part had a bunch of “Ears” on it that formed a pocket of sorts. In one area the shortest reach we had to get to the corner from any direction was 3 1/2 inches. It was a military aerospace part and the customer refused to change the radius despite the fact it could have been 1/2" rad. That was fun…06" radius in 316SS with a 4" tool. We ended up making special extensions and breaking a whole lot of tools.
Here’s a few
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Always think “How is that going to be made?” If you don’t know how to make don’t design it or find someone that might actually know if it can be made.
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Watch your reaches. Making a feature that needs a 1/8" end mill to make and you can only reach it with a 10" long tool is bad, very bad.
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Ask yourself “Do I REALLY need”
a) ALL those threads?
b) That tight of tolerance
c) All those radii -
How many setups - Goes back to “How and I going to make this”. If you can make a part that works with features on three sides…don’t put features on four sides.
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“Pretty” is expensive.
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Pay attention to materials. Making a part out of a tougher material may be necessary, but if it really isn’t you just double the cost of your part.
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You can’t ever have enough information on the drawing. No one ever walked into my office, plopped down a drawing and said “Dude there is absolutely everything I need on this print to make the part and then some”. A view takes seconds to add in a CAD system, ADD THEM. Notes, dimensions, reference dimensions, more views. Make the views clear, large enough for an old 60 year old machinist to see and understand.
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Fancy is expensive. Don’t over design something because you’re being clever and putting that expensive engineering degree to work. If a block with four holes fits the design requirements, don’t turn it into something else to make it “Better”.
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Know enough about making parts so that when you’re done with the part the person making the part can look at the drawing and know how you want it made.
For a start…
I’ve made lists like this for designing plastic parts. Some of the plastic manufacturing process goes through the machine shop. Sometimes it’s hard to think that far ahead - thinking of the part design and function plus the mold and the mold making process. It can be a lot to think about all at once, but it comes with experience, and usually with the memory of a red-faced machinist yelling some unintelligible at you before you can sit down at your desk in the morning. It’s good to hear what other people need, though.
I worked in production before i started to learn SW. That is most helpful thing i have today while designing 
Also , i really try to have good communication with our production , and i am not ashamed to ask questions what is easier for them to make.
Amen to all of the points in this thread so far; I used to train new “Essentials” users on Inventor and by far the best users were those who had previous machining experience.
In one class in particular, I had a CNC machinist sat alongside a Mechanical Engineering under-graduate and when I mentioned ISO Limits/fits & Tolerances all I got was a blank stare from the University chap.
One point I would add is this:
Specify fewer bolts; a standard 5mm bolt can support a 1000kg mass. In fact, the material the bolt is attached to is likely to fail before the bolt does.
PS. if you ever wonder why Herman Miller chairs are so expensive, it’s because a) they make great chairs but also:
(I know because I had to clean their CAD models for use in CET Designer - man that was painful)
That’s an excellent start!
One thing I would add right off the top of my head is to dimension your model to the mean of the tolerance. Most CAM programmers who use the model, create their toolpaths right on the model. If the dimension is 1.000 +.010 / -.000, model it at 1.005. When you model it to the high or low the CAM programmer has to make changes to get the toolpath on the mean. Yes, you can have the machinist on the shop floor use offsets to get the part on the mean but I prefer to give them a clean program.
Does a plasma count as CAM too?
Sure. Plasma, waterjet, laser… all CNC driven.
That’s a great list MJuric .
I frequently run out to the floor and measure tools to see if we have a certain size drill already in stock, or if a standard ER32 toolholder will clear a sidewall, or if a standard tap will reach XX deep, or what the corner rad is on CCMT32.50.5 inserts…you get the idea. An engineer who has no experience in machining or doesn’t bother checking tooling capabilities will make life very miserable for the machining dept.
And nothing ruins your day quite like having and angry, smelly, likely hung over grumpy old machinist standing over your shoulder foaming at the mouth and teeth grinding all because they broke off a tap in a part because you made them use some ungodly length tool or tool extension.
One of the things we used to do to machinist was create a “Scrap tree”. We’d hang a chain off their machine and every part they scrapped we’d tac weld it to the chain. To this day I keep a well stocked pile of “things I screwed up recently” on my desk as a reminder to pay attention to what I’m doing.
I’m afraid I don’t know anything about CAM, but I could go on for hours about engineers with no practical experience designing things that are much more complicated than they need to be to achieve the goal, spec a material that’s only made in limited quantities on February 29th, or call out rebar bent to 1/16" tolerance.
This is actually quite a challenge for me when designing machines. On one end of the spectrum you’re designing something like a spindle where tolerances reach down into the .000X" range and sometimes less. Then you switch to the enclosure and you drop a tolerance down that is +/-.03 and you think you’re giving all the tolerance in the world.
I always have stop, switch gears and realize that I’m now dealing with a guy at a break press using scribe lines not a highly accurate machine with glass scales and linear rails. That guy is NEVER going to be able to make four bends on two parts and have them fit inside of each other +/- .06"…not going to happen. Well maybe it might, but it would be more luck than being able to hold tolerances.
Another challenge I run into is one of scale. At one time I was working on two different projects at the same time. One was a desktop unit with eight lanes that processed chemicals and media for the medical industry. LOTS going on in a tiny area. At the same time I was working on a project that filled three stories of a building. In one I would drop an M16 bolt in and it would be WAY to small. I’d then switch over to the other and drop in an M8 and it’s cover half the screen
Or call out surface flatness 0,1mm on sheet plate 1000x1000mm ,1mm thick, becase “i need this side to be flat”. 
I’m trying to see what your problem is with this…
You really boiled my blood ,than i had a click for font colour