Attitudes in Machining

[dapoling]

The reason I am writing this as for years and even today to include in the forum you can see several views on attitudes.

We have the follow traits:

1. Don't care
2. Just do enough to get by
3. Just take short cuts
4. Just get it done and out the door
5. Want it done right the first time
6. Overly nit-picky

You may have your own categories and well I place my self in between 5 and 6.
I like to see those that take the extra steps it takes to setup clean and accurate and use those tools you have to make it right to begin with.
I strongly believe that tolerances are for production not in your setup or programing.
I have seen people fired for doing what they were told, as we know there are some of those out there that talk a good game but have no clue.

One incident I ended up being involved in and not by choice.

There were several difficult parts well at least management thought so and took stock into 2 machinist one being a lead and the other considered the head machinist.
Over a 3 month period 3 machinist that followed this head machinist were fired and all said when they left they did not do the scrap and did what they were told.
Then the Shop Manager came to me and placed me into the position following this head machinist, I thought oh boy.

The first part that was up and running was a casting that had 5 different setups and had a true position tolerance of .005 and he had them convinced that they could not get any closer then .006 true position, do to the machine.
After inspecting the part off it was out of tolerance.
I brought the test indicators and went through the setup and corrected it, next part off was in tolerance and there after.
I left message explaining what I did and the results.
When I came in the next day it was the attitude of "what you did, did not change anything" so when he left I setup a part and inspected it and it was again out of tolerance at .006 true position.
The indicator came out and the setup was fine, I checked the program and it had been changed to make the part wrong.
At this company we kept a hard copy and then one on the server, the server program had been over written.
The next day he was pulled off those jobs and 2 days later him and his friend the Lead were fired.

After the rest of the hard jobs were straight out they all became easy to run.

This is my point take the time to do it right it will make your life easier and will avoid others being accused of poor work or worse fired.

This is why I also have my signature as it is.

[handlewanker]

Hi DA, you'll find that #4 is the most important attitude you can have, that is if your the boss and you're paying by the hour.

Too many people take "great pride" in what they do instead of getting the job done and out the door.

Couple of firms back that I worked for had an old feller that spent most of his time polishing the job to make it look nice, as he was close to retirement and not in the best of health, so he just got by on what he did.

This meant the boss, (both of them), were constantly breathing down your neck to see the job finished.

Most of the bosses I've worked for went for production, what went out of the door was money in the bank.

It goes without saying that the job must be right, IE if you bodge it, it's going to bounce back on you, so then you just gotta learn to not pissball about and keep your mind on the job.

One guy I worked with was a real pain in the rrrs, he would spend the first half hour of any job cleaning the machine down and beeching about the calibre of those that worked on it before him.
Ian.

[Geof]

Originally Posted by handlewanker Hi DA, you'll find that #4 is the most important attitude you can have, that is if your the boss and you're paying by the hour.....

You may find a lot of people have this attitude; that doesn't mean it is the most important. Even if you are the Boss this is a good way to go out of business; the correct way to stay in business is do it correctly in the most efficient time and with the most efficient use of materials and tools. And don't overdo it; if a tolerance calls for +/-0.001" don't waste time going for +/-0.0002". Between 5 and 6 is okay so long as you don't start drifting too far toward 6; going any diistance from 5 back to 4 is not okay.

[dapoling]

Very good points, when I do setups and run my first part I go to nominal and then use part of the tolerance before adjusting.

If one has a +/-.01 then as the tool dulls some adjustments can be made with the idea of
looking at replacing your dull tool when your adjustment exceeds 50% of your tolerance.

One must as well take into consideration of how many operations the part requires and how the referencing surfaces will play into the accuracy of the other operations.

It is possible to use up your tolerances on the first 3 operations and then in the 4th and final one you loose the part do to some over tolerancing engineer or someone that has used every bit of tolerance up before getting there.

There are many owners that have no idea nor want to know what it really takes to produce quality parts in a timely manner.
Taking the time to have a proper setup is very valuable and cannot be over looked or one will find themselves in scrap or special handling parts which all cost money.

[Geof]

I thought a bit about the attitude(s) people do have versus what they should have and came to this conclusion: The attitude you should have is the one you want in the guy who repairs the brakes on your car or who maintains the airplane you are going to fly in.

[cam1]

I second Geof's comment, I work with AME's, and were you aware that Aircraft mechanics earn about the same amount as automotive mechanics?
PS I do my own brakes, as I've seen some of the talent that shops use to repair brakes......

regards

[handlewanker]

Hi Geof, I get your point, I still maintain, and that's MY opinion, that if you spend too much time polishing the family silver the kids will only sell it off when you've gone.

By that I mean, if you want to win in this world it's the first one past the post, no matter how.
By the way being a yank, how do you feel about the dollar now, OOOOOPS, forgot you be yarkshur born 'n bred, now a Canuk.
I've been checking out the USA Ebay, boy what a lot of bargains there are.
Only trouble is the shipping is crap.

After that rant I think I'll lay off the vintage Port I've been sipping for a nightcap, tends to make the screen a bit fuzzy.

Actualy, the whole point of the matter comes down to design.
The tighter you tie up the dimensions the more expensive the job becomes.

When I was quoting for work I always carefully noted the number of high tolerance dimensions, this dictates the price, and usually this is a sign of an inexperienced draughsman or design person.

On one job I quoted for the dimensions were so ridiculous I just had to go back and personally check out the designer/draughsman.
I asked him casually if the dimension to three decimal places,(metric), for a shaft length of 600mm was on a 35 deg C day or something cooler.

I don't know what your drawing designates are in the USA, but in OZ, or at the firm I last worked for, the tolerance to one decimal place is +/- .25mm or .010" in imperial, no matter what the part is for, and to two decimal places it is +/- .01mm etc etc or half a thou.
The tolerances were never attached to the drawing dimension, only the decimal place points being the indicator, unless otherwise noted.

I never saw a drawing with three decimal places to metric, that would have been +/- .001mm or one thousandth of a mm.
I reckon the part would grow out of tolerance if you held it long enough.

One of the golden rules of engineering is K.I.S.S. and this starts with loose tolerances, the moment you start to tighten up the sizes, up go the costs, at least you get plenty for your scrap returns.
Ian.

[Geof]

Originally Posted by handlewanker Hi Geof, I get your point, I still maintain, and that's MY opinion, that if you spend too much time polishing the family silver the kids will only sell it off when you've gone......

You are perfectly correct. But, if you don't follow my approach they are likely to be selling it of earlier than necessary after having you pulled out of a big hole in the ground before putting the bits back into another one.

[handlewanker]

BTW, If anyone thinks I'm just a cheap bodge merchant that would push a job out of the door in any condition just to get rid of it, far from the truth.

I started out the wrong way, being apprentice trained in a cosy environment with all the facilities and time to really ponder on the mysteries of mechanical application.

Five years later it was helter skelter in the rat race as one employer after another drummed it into my head that they weren't paying for spit and polish.

So at their demand, corners were cut and economies were made, but never at the expense of doing half a job, that would have meant dismissal for ineptitude or shoddy work practice.

So #4, you just get it done and out the door, time is money, next please.

Anyone working to #1 2 or 3 is doing so from their own shoddy work habit, which means you wouldn't want them working on a root canal job in your mouth, even if THEY paid you double.
Ian.

[dannystooblue]

I wonder how many people that vote #5 have cut a pinky finger off for their last mistake? How many of them vote that and actually live a #4 but would never admit it? I have worked in the trade for 18 yrs now and have seen so many from one extreme to the other. You tend to see more willing to get it done and out the door that proclaim perfect the first time every time. I have had to help repair some of these perfect parts where a self proclaimed #5 was really asleep at #3's wheel. I think the bottom line is #4 parts = income! If you make a bad part you don't sell it like that, you fix it or replace it, end of story. Don't slow down to cry about spilled milk, just make the parts. The guys that are really #5 tend to turn out about 1/2 the work as #4 in genneral, now and then you run across an exception... I am sure if your a #5 and reading this you must be the one, I am not trying to hurt anyones feelings

Danny

[dapoling]

The categories leave a lot for interpretation and will differ from ones experience to anothers.
I was referring to the setup and I could have been a little more clear on this but I didn't when I wrote "Want it done right the first time" as I have seen those also that claim it but end up with junk for others to fix as well.
The thought I was using is to produce a setup accurate enough to produce good parts in a timely manner with out having to rework or produce scrap. Thus working with feeds and speeds, loading, debur of parts need to locate accurately thus eliminating rework and saving time.

[pixburghenat]

...I was told once I had a 'bad attitude'.

and I told them 'my attitude was just fine until I met you'


I #5

...sometimes #6


enat