Common Machining Problems

[MecInd]

Could anyone tell me the main machining problems from milling, turning and grinding and how they are over come. Stuff like chatter, poor size holding, surface finish and stuff like that please.

[PixMan]

I believe the single most-common machining problem encountered is that the guy running the machine only knows 1/2 of what he should know. Solve that, and the world will be a better place.

[aaron p]

Originally Posted by PixMan I believe the single most-common machining problem encountered is that the guy running the machine only knows 1/2 of what he should know. Solve that, and the world will be a better place.

It takes a lifetime to learn 10% of this trade. Proper training and the understanding of the physics of machining will produce a good machinist. There is no such thing as a "master machinist" in my book. Thats like saying your perfect at every single type of machining known to man. If your in a production shop like myself and make alot of the same product line, youve gotta know how the final product is used and the areas on your print that are most crucial to the products performance in its use. I do 5 axis machining, and ive made mistakes before, but never made the same mistake twice. My leadman the other day said, "A real machinist is part engineer, part mechanic, and part machinist".

I guess what im trying to say here is, the biggest problem I see in machining is bad habbits being passed on to new machinist coming into this trade and the lack of interest in the real world of machining from new machinist. Most guys just want to get their check and go drink beer at home.

[aaron p]

Originally Posted by MecInd Could anyone tell me the main machining problems from milling, turning and grinding and how they are over come. Stuff like chatter, poor size holding, surface finish and stuff like that please.

In regards to chatter on the lathe, use the biggest tool holder you can and the right inserts for the job. Milling chatter also usually comes from bad fixturing and feeds/speeds or DOC. Lathe surface finish issues usually come from using the wrong insert or SFM for finishing. Dont be affraid to experiment, not every feed/speed chart will be right on for every job you encounter. Spindle horsepower will also affect things like this. As an example, I was running a special Buttress thread on a I.D. the other week and they programed it to finish the O.D. 1st (wrong to begin with, but they didnt want to change the program). I ran the 1st part and it had mild chatter on the threads, so I thought on the next part ill leave the OD rough and big so it isnt soo thin with the threads. Sure enough, it worked. Like my signature says, "think outside the box"
Im only 24 and enjoy my job alot! Got alot to learn though!

[Mcgyver]

Originally Posted by MecInd Could anyone tell me the main machining problems from milling, turning and grinding and how they are over come. Stuff like chatter, poor size holding, surface finish and stuff like that please.

I'll be harsher; main problem is people aren't willing to buy and read a couple of books and spend the time at it to learn; they expect instant knowledge and gratification like its a video game. Its almost unbelievable the parade of people expecting good results who've put more effort into say learning to drive than this complex craft.

anyway, its something that you only improve at not master even after a lifetime; how can that be distilled down to a paragraph other than to say one must be enthusiastic about learning and seek it out to do well at this.

[DareBee]

Agreed, there is no way in hell we can answer a broad base question like that.
As mentioned it takes a lifetime to get good at this stuff and there is still always things that F U up and make you scratch your head.
Technology and materials are constantly changing and so are the methods of the trade.
It's live and learn

[Thrasher]

I heard someone ask a friend of mine one time: "What is the key to successful business?" My friend without a minute of hesitation said: "years of losing money." It takes a lifetime to learn "All" the tricks, tip and processes. Funny thing is.... I KEEP learning new things..... every day!! I Love it!!! There are now easy answers, and an answer for one my not work for the other!