[cncwhiz]

After many years of headaches and dumming down my programs, the big bosses have decided to let me train the machine operators. Some or most of these guys are green as can be. Some came from Walmart etc, you get the picture. I will have different levels of triaining as that some people know more than others. I will be teaching only the "G and M" codes that we use here in house. They will be learning what and how to do work and tool offsets and basic reading of programs. After almost 30 years of machining I'm sure there are things I will overlook. I will be showing them the difference between a dull and sharp cutter etc. I would like to teach them what dull and sharp tools sound like but how to do this and how much time would it take to do this? I am looking for input from people who have or are doing this in the "real" world. I will be doing this in both the classroom and at the machine.

TIA

[electromech31]

Start by finding out exactly what you need to teach. Second find out were you students are at with their skills. I have found a great site http://www.jjjtrain.com/vms/, I have used it for examples to my students. Also look for some industrial standards, http://www.nims-skills.org/downloads/downloads.htm, so you can say that the students were taught such and such. (save your ass later)

[ImanCarrot]

The jjjtrain site is tops for general info.

What a sharp/ dull tool sounds like- What I do is use a microphone which I took apart and blu- tacked to the spindle housing. I use headphones to listen to the tool cutting- it's a huge advantage. I daresay you could stick the output into your PC or even a tape recorder to play it back to your students?

[cncwhiz]

electromech31,
That first link is good stuff. I will be using it a lot. That second site is pretty good too. There is so much to think about for this issue as that not everybody is at the same level. You don't want to waste production time training someone that could be making parts that allready knows the topic that you are teaching at the time.

ImanCarrot,
Your idea sounds pretty good if all things are taken into the sound ie; tool type, material type etc...

[MazakMikeO]

One of the ways I have used in the past to train apprentices is to show them a certain task, say taking a tool length offset, then let them try. Usually they won't pick it all up straight away, but as they are going through, I would watch for a mistake, and if it won't do any damage let them carry on, then stop them, point out the mistake and start again.

The best way to learn things like this is by doing, and doing again in my experience. Let them make mistakes, but not ones that damage anything. But you definately need to sort out different levels first.

That in my opinion is the hardest part.

[cncwhiz]

I'm starting to get an idea of how I need to go about this task. These guys all push buttons everyday, so I think the first order of business is to actually learn the basic concept of what the program is doing. They have a very general idea as that they are running the machine.

[tauntdesigns]

One thing alot of mill operators seem to have problems with, is making workpiece offsets. Some have to look on the machine at the labels (X+, Y+, etc..) and then use their hands to help them try and picture in their mind which way to go... and some still make the wrong change. Some think it matters what type of machine it is (table moves or spindle moves) which I say it doesn't matter.

If you're running part and you have a 1 inch dimension from the left edge of the part to a hole and it checks .990. I look at as the feature (hole, web, etc) needs to move right .010. When you move right on a X,Y graph, that's in the plus(+) direction, so make a plus offset in X workpiece offset. It doesn't matter what type of mill machine you're on.

So, if a feature needs to move right(X+), left(X-), up(Y+), down(Y-), deeper(Z-), and less deep(Z+)

Now I'm confused
Jack

[cncwhiz]

I'm always the spindle, this makes it better for me to understand. It gets worse for those kind of people in my shop. We use hex tombstones and machine two parts and six sides for most of our setups. We do not have verticle machines in our shop so it can get a little crazy.

[tauntdesigns]

Being the spindle is same as I was saying... to get a feature to move to the right you'd have to move the spindle right. All mills are programmed like a X,Y graph... even horizontals.

Right(+), left(-), up(+), down(-), in(deeper(-)), and out(less deep(+))

Horizontals are basically a vertical laying on it's back. The X,Y graph is taken in from the operator's positions, point of view.

The only difference I've found with Horizontals are the direction table rotates. Some I've run rotate clockwise with (+) direction and some counter clockwise.

[cncwhiz]

tauntdesigns,
That will be down the line for most of these guys. Like I said in the begining of this thread, most of these guys arn't even button pushers. My main idea at this point is to have them understand what the programming is doing so they can set an offset or start the program back up after the weekend or intrruption. I use "G10's" so they won't be setting to many work offets. My programs use subroutines and are all over 2,000 lines.

[tauntdesigns]

cncwhiz,

Do they mount their own tools, if they do.... this was something we addressed with some of our button pushers. How to draw the end mill up in the holder with the set screw so if the tool holders set screw loosens up a little the tool has a better chance of not cutting to deep. I know it sounds simple but ........... Do you G10 the tool offsets too from a tool pre-set area or do they set them on the machine.

Cheers,
Jack

[Mitsui Seiki]

One thing that helped me when I was new to this and the ones I have trained is this, -(Minus) = more chips , +(Plus) = less chips.

[cncwhiz]

I don't use "G10's" for tool offsets. We manufacture our own product so the tool in the magazine and machines pretty much run the same parts. Other than minor revisions which I handle myself or the supervisor they just push buttons and load parts. I know that all I really need to do is teach them to read a program enough to get them up and running, be able to tell a dull tool and check the offset to get the machine back up and running. I will be doing much more than that. This professon has treated me well so I want to give as much to other people as I can to be able to do the same. I will tech them as much as they can learn so they can be able to leave this shop and go anywhere.

[MazakMikeO]

That's a good attitude to have, I hope they have the same attitude towards learning.

[cncwhiz]

Their supervisor does not want to teach them anything. Everytime I go to the floor to prototype a job they pick my brain so I thnk they will enjoy it.

[billystein]

Hi,
I like to have the guys make setups. I mean indicating vises, edge/center finding. setting tools and offsets. even on there first day. I believe that cnc operation and even programming can be learned in 1 year or so. machining however can take a lifetime. when a person makes setups all the time they get faster. i don't have them run the programs until they are ready.
by that time they are really good at indicating fixtures and vises and setting tools. I ususlly run the first part for them and check everything out.
after a few months you should see who is definitely not going to be a machinist. the guys that i have trained have usually been very fast at setups. i mean faster that most guys that come through the door. to this point only about half a dozen guys that i have trained have gone on to programming. I don't push it on people and i make them decide if they want to do it. it seems that most guys are not willing to take the next step.
I had to learn most everything by myself except for a couple of training days at machine dealers. I was hungry to learn and always had some nc book in my back pocket. I would read while my machine running,during break and lunch and always in the bathroom. my bathroom at home looked like a nc library. I don't see that in most people. I see them reading the newspaper daily. they never miss the sports section. one freind of mine has been waiting 20 years to learn programming. he is a good operator and setup guy. he can programming some drill cycles and makes fly cutting programs. he still wont take the time to read any of the programming books. the computers were always available at lunch and break time but everyday he would sit 4 feet from the computer and have his lunch and read his newspaper.
I taught him a few lessons about machining but he will never put the effort into learning programming.


billy

[tauntdesigns]

Great attitudes guys,

I've always enjoyed helping others at work. It sounds cornie/korny but, I get a kick out of seeing the look on someone's face when they finely get it.

Happy machining,
Jack

[cncwhiz]

Billy,
Your idea will work good for a job shop making "simple" parts. No one can "correctly" program in a year. They need to know method, sfm and ipr for cretin tool and materials etc... In the company I work in we make our own product so all are parts for what we make. We have for the most part machines and fixtures dedicated for what we make. I don't use any vises. I use tombstones with pinned and bolted sub plates. I use "G10's" that are pre-programmed. The tools stay in the magazine. This makes for a simple way to run production but a not so great place to train. I have been dumming down for so long with macros and safegards all over the place that they don't need to think. This is great for the bean counters and money people but does not help the people learn how to "correctly" setup and operate the machine. The only good way to learn this trade is to go from shop to shop over many years with different conditions, money etc to become a good machinist.

[dumptruck]

Start with The Green button, the little red button, and BOZO's NOSE !!!!
Try explaining that cutter comp "D" value is actually radius. That's because "R" was already in use for G02,G03 circular interpolation. C.N.C. milling is programmed for the spindle to be "offset" from the parts outline in relation to 1/2 the cutters dia. To adjust a side g41/g42 the "d" value is actually the radius. That's because "R" was already taken for g02,g03 etc. Then go on to circular interpolation and then the hole size doubles the "D" value because on a circular path the tool cuts on both sides so the "D" value offset doubles. Now how many fingers ? HA HA !!!