[sambo67]

Looks to me if he had to but that chuck he would quickly learn what a drill chuck is designed for (here is a clue , almost $400 )

[sti2011]

Truthfully we have all done things we shouldn't have out of neccessity or ignorance. And gotten away with a few here and there.....
I agree with the poster that given the fact that R8 collets were available and the machinist's experience level was sufficient....Then this had to be a case of either sloth, indifference or both. Either one would have you on the carpet or bringing your toolbox out the door at my shop.
If that was in fact a Jacobs taper, which it looked like...Knocking it off the taper at the 2600 to 3500 rpm he would, or should have been running that end mill, is capable of hurting alot more then just the part and tooling.

[NEATman]

I recall seeing someone doing that very same trick on thier second day of work - except that he had the three jaws tightened up good and tight on the 4 flutes of a double ended 3/8" endmill!
Needless to say, he didn't finish his first week. He did however destroy the chuck, the end mill, and the part he was "reworking".

Keith

[Shotout]

My point is that it is not always valid to jump on someone for doing something wrong; I would rather have a guy who knew enough to know when 'wrong' is okay, rather than someone who is totally hidebound.

You're right of course. I've done some unorthodox things myself because I've needed to and just took a little extra care until I felt confident of the outcome and have learned some "cheats" from much more experienced machinist that I've tried a time or two when I was feeling brave or just had to get it done.

What I didn't get into in the original post is this isn't the 1st time he's done this, nor the largest diameter end mill I've seen him do this with. This is also the second one of those drill chucks we've bought in less than a year. The last one is still sitting on a shelf to be sent out for rebuild. Nor the first time I've talked with him about using the quill for a knee, nor about spinning a handle on a cnc machine and crunching an electronic height setter etc etc.

Something else I didn't get into those of us in the engineering dept where all feeling particularly grumpy that day and I got elected to post this. We all need to scream at the heavens at times and as this place feels as much like home as anywhere else to me and my lead also uses this site we thought of ya'll. After all what are friends for, other than borrowing money from <snork>

@morehelium My cell phone camera isn't that fancy and believe it or not that is actually WD-40 in the bottle

@sti2011 It is poor work ethic I think. I really like the guy personally and since I changed shops last year and moved across the state no one here knows where I am (or cares) so there is no chance of him being embarrassed in real life by the post. As I said to Geof this was after a really frustrating week last week and a poor start to this week.

My Karma or Feng Shea or what not is much better now as I ran that mill for the better part of the day working on some critical stuff for a job. I like tramming a mill, indicating a vise and making chips, I just don't get to do as much of it anymore.

[sti2011]

Interestingly some the posters questioned what was wrong with the pic...Could be a good thread to start for the less experienced.(pics of what not to do and why..)
I am not into ridiculing people, or needing to have my ego fed. I suspected that if that was done by someone in-experienced you would not have posted it. But it could be helpful to others if these faux-pas are posted and debated.

[Geof]

....What is wrong with the setup?"......

.... using a 3 jaw Jacobs chuck.....

As I mention above there is nothing specifically wrong with a setup using a drill chuck to hold a small end mill; provided the drill chuck is an integral shank style.

Using a Jacobs type chuck is very bad practise and can be dangerous. Drill chucks are intended to take an axial load, not radial. The Jacobs taper that is commonly used to mount a chuck onto the spindle of a drill press or onto an R8 adapter for the mill is a small angle self locking taper. Under an axial load it is forced on tighter and is perfectly capable of transmitting the torque load for the largest drill the chuck can hold.

However, a taper connection, whether it is the short Jacobs or the longer Morse taper is not suitable for holding a cutter subject to an axial load; no matter how smal the axial load is. The combination of rotation and constant side loading will eventually work the taper loose, the chuck will fall off still spinning and can turn itself into a spinning projectile carry a very sharp cutting tool.

Holding an endmill in an integral shank chuck is not good practise but it is acceptable. The difference between a drill chuck and a proper collet chuck is that the jaws of a drill chuck only make contact with the cutter over a small area so the localized forces are high. If a heavy cut is attempted these high forces can cause deformation or chipping of the jaws. Also the drill chuck jaws are unlikely to run as true as a collet; although I have been surprised at how true a godd integral chuck runs.

I notice while I have been dithering about typing this additional posts have made it a bit redundant.

[jbarcelo]

I'm a novice. Could anybody explain what is wrong?

[mopar]

He did not learn that one at Tech school ,believe me!

[Shotout]

Interestingly some the posters questioned what was wrong with the pic...Could be a good thread to start for the less experienced.(pics of what not to do and why..)
I am not into ridiculing people, or needing to have my ego fed. I suspected that if that was done by someone in-experienced you would not have posted it. But it could be helpful to others if these faux-pas are posted and debated.

Your right. We've got a couple of inexperienced guys, one fresh out of school and one good tool and die man that has moved over to the cnc side of the force and I'd never discuss their transgressions with anyone but them. Although I do like to watch the tool and die guy work on the manuals. He's really in his element then and is pretty danged good, certainly better than myself.

I've been very fortunate so far in my career and have received guidance from others, Geof being one of those people here online, as well as in shops. I try and pay that back whenever I can. I was once told by a mentor that it is a sin for a man not to pass his knowledge along. I try and live by that.

[coop2005]

I am no machinist, i am more on the design side, if I gave you a part to make i don't really care how you made it but does it meet the specification on the drawing (tolerance surface finish etc.) if so is there a problem? I do some work in our shop on the cnc mill and have always wondered about the runout on this type of chuck. Is it unacceptable?

[Geof]

......I was once told by a mentor that it is a sin for a man not to pass his knowledge along. I try and live by that.

I agree. We would still be living in caves and hunting woolly mammoths with stone tipped spears if knowledge had not been passed from generation to generation

[packrat]

While I am a "manual" person, the - BASIC - shop practices do not change. I tried teaching in the apprenticeship program where I worked, but got frustrated fast. I learned in a jobshop and the other teachers learned in house.

The difference was no one in house was ever taught "common shop practice" They didn't think stuff like make sure there was no chips under your parallels meant any thing!

cary

[Shotout]

I am no machinist, i am more on the design side, if I gave you a part to make i don't really care how you made it but does it meet the specification on the drawing (tolerance surface finish etc.) if so is there a problem? I do some work in our shop on the cnc mill and have always wondered about the runout on this type of chuck. Is it unacceptable?

That chuck is a drill chuck. Drill chucks as the name implies are for drilling. Used and maintained properly no it won't have a lot of run out until long into it's life, right up to the end of it's useful life in fact. It can be rebuilt or replaced at that point. As an end mill holder it is a spinning mass of potential doom or injury. I also know that if it is spun up to fast the shank will come loose, probably from being used as an end mill holder in it's short past. If you look at the picture you can see it has a collar to hold the shank on above the body. That is so it can be attached to a suitable shank, be it a morse taper or straight shank as in this case.

[Pressfit]

I've never seen an Albrecht chuck head that did'nt come with a tapered bore for mounting to some style of machine arbor. Every one I ever dealt with either came with a No.2 or No.3 Morse taper and that one in the pic looks like a 1/2 chuck.

Even though there are points here about the technical aspects being right or wrong, there's a glaring consequence I would be concerned about more than anything else, and that is the (time) it takes to do it that way when there may be collets available there at the machine or tool crib.
It's a completely different story if that's the ONLY way one has to get it done and/or you have all kinds of time. It works but it's incredibly slower like that than simply putting a full size, 2 flute, 1/2 inch endmill in a collet and plowing thru that aluminum at 1500 RPM like it was butter.

Anyway, besides cutter torque causing more flexing into the work on conventional and pushing away on climbing, it's also likely it will suck-out of the chuck towards the work. You will see that happen even on collets.

[joepuppy]

Well, some of my greatest machining "lessons" were learned at the butt of a joke or even with good old fashioned sarcasm. Those tend to be the ones I never forget. Endmills have no place in a drill chuck. End of story, as far as I'm concerned. I'm sure Mr. Albrecht is rolling in his grave. Of course, some people are satisfied with "close enough" or ' whatever works", but this goes against the very basic principals of machining: accuracy.

[RomanLini]

No no! Don't give away all the secrets!

Zeeshan and his Chinese co-workers are now all running around removing the Albrecht chucks from their X2 mills that they use to make car engines.

[lgalla]

Whats wrong with these 2 pictures?

[sti2011]

First thing that comes to mind is, I noticed a few other pcs. of junk lying around that were not somehow worked into the fixturing of the part. ;0

[MyCattMaxx]

First I see a DP being used. Second I don't like the way he raised the work. Looks not to stable.

[Delw]

Whats wrong with these 2 pictures?

Thats an easy one.
the laptop key board has chips on it in the first picture and in the second picture the lap top screen shows NO porn WTF is up with that?