Pacman - Machinist School Tool

Here's a problem - How to locate a corner when the part is at an angle.

Perhaps you have to drill an angled hole or slot a certain distance from the "corner" of a square part. Typically the problem is confounded by the fact that the "corner" has been rounded during deburring. You need a Pacman-Machinist School Tool

Machinist School brother Dave Renfro invented the Pacman to solve this problem. A 1" cylinder with a 90 degree v-groove solves the problem. An edge finder can be used to locate the edge of the Pacman (1/2" from the corner). Using the Pacman, a cutting tool can be also located 1/2" above the corner.

Similar to a v-block, the Pacman has a relief groove cut at the apex of the angle. Of course, the V is cut to ensure the apex of the 90 degree angle coincides with the axis of the cylinder.

Other Pacmen could be made for angles other than 90 degrees. Maybe you envision other uses for the Pacman.

Thanks Dave!

HAAS TM-1 CNC Milling Machine

Here at the Machinist School in Northwest Arkansas, we have a Haas TM-1 CNC Milling Machine. The TM stands for "Tool Room". There is one basic reason for the choice of the TM-1 mill. That reason is because the Haas control panel is standardized ..... Haas uses the same basic control panel for all of their machines and has done so for over 10 years.
Why are you using Microsoft software? Because it is the greatest? No ..... because it is a standard. When you choose Microsoft, you have chosen compatability.
Would you buy a car with the gas pedal on the left and the brake on the right? Not likely, huh?
Same thing with Haas. When an operator has become familar with the Haas control panel, he has become familiar with ALL Haas Control panels.
Of course, there are odd things one would not expect. For instance, Haas has their own version of 5/8 of an inch. A machinist would say .625". Many setups on a Bridgeport mill became standardized to the 5/8" T-slot in the table of the mill. Haas wisely chose 5/8 inch as their T-slot size. Unfortunately, 5/8" is subject to tolerances. In this case, about .011". The 5/8 T-slot on this mill is about .636. Not Metric, not an American standard. So we make custom parallels and keys for the fixtures to accomodate this quirk.

Sharpen Your Knife - Machinist School How to

Here at the Machinist School, we engage in the education and technology involved with the instruction for those who want to learn or sharpen their skills in the field of stones for creating edges that cut.
There's not much magic .... it's a matter of doing it.
There are a number of tools and techniques that are "the ultimate".

In olden times, people rubbed their knife on a rock to create a sharp edge.
Then as time went on technology didn't change much but they changed from using a rock to using a stone.
When things got industrialized, some people specialized in the business of stones-for-sharpening-knives. People that had been stone masons figured out that building stone walls was a lot of work for not very much money. Some of them discovered the concept of jewelry and gemstones. Others discovered the sharpening stone. Either way, the rock became valuable as an individual item of trade rather than simply part of a wall.

Stones-for-sharpening-knives was too much to say in one breath so the search for a better name ensued. Though lots of explanations exist, what we know is that the word "HONE" emerged. Nobody was sure if HONE was a noun or verb. Was the rock a hone or was the process of using a rock "to hone"? Some folks call the rock a hone. Others say it is a hone stone. When used around the house, it is a home hone stone. When used at homes of little people, it is a gnome home hone stone. In certain parts of Italy it is a Rome gnome home hone stone. When an Italian woman throws it at you it is a Rome gnome home hone stone thrown ........... you get the idea, I suppose.
Anyway, manufacturers of hone stones try to differentiate their rocks from other rocks with pamphlets on "How to Care for Your Hone Stone" ........... well, duh ......... how do you take care of a rock?????????????????????????
Anyway, your knife will eventually get sharper if you rub it on a hone stone. It is cutting edge technology.

Stirling Engine at the Machinist School

In the foreground is a traditional Stirling Engine at the Machinist School. Under the torch is a modern Stirling Engine. One reason to be a machinist is so that you can make things you want to make - like a Stirling Engine. One advantage of a Stirling Engine is that there is no steam boiler to blow up. A Stirling Engine can be "Green" .... it will run from the heat of sunlight. The air in the engine recirculates and never exhausts .... it just keeps heating up and cooling down, resulting in a wheel going around in circles and NO pollution. Stirling Engines have been used to power vehicles, boats, and equipment. Variations are used in outer space.

Ceramic vs Styrofoam at NTI

This is a snowman riding a snow duck at NTI - perhaps a new rodeo event? Probably not but it does bring up the topic of material science. The snowman is made partly from styrofoam. The duck is made from snow (ice crystals).
Styrofoam is not edible although it is a carbon-based material. Since it is a light weight material, some folks use it as a "filler". Again, just because it is filling, don't eat it!
Snow is simply water in a solid form. Water is made from a metal (hydrogen) and a non-metal (oxygen). Some folks don't believe that hydrogen is a metal. At room temperature, hydrogen is not only a metal, it is a vaporized metal. Other people wonder why water doesn't burn since it contains hydrogen and oxygen (actually water is burned up, oxidized, hydrogen ..... hydrogen ashes???). Anyway, another generic name for a metal & non-metal combination is "ceramic". Aluminum Oxide is a popular ceramic. Like "Plastic", "Ceramic" isn't really a material. Ceramic is a property - a set of characteristics - if it walks like a duck and quacks like a duck, it must be a duck!
That leaves us wondering ... are Igloos ... are they ceramic houses?

Machining vs Duck Farming

Sometimes things collide. Such is the case with the Machinist School and Rod's Duck Farm. This graphic was sent by Tom Freking in commoration of the Chain Saw Sharpening and Duck Farming exploits. This is the last week of the Free For February Ax & Chain Saw Sharpening. The world is now a little sharper.
Quack, Quack!

See the Zac Lehr Photos .......

Zac Lehr at The Morning News stopped by and captured this image of the Chain Saw Sharpening Process here at the machinist school. Really neat photos. You can see more pictures at his blog:
http://nwabehindthelens.com/2009/02/18/im-a-lumberjack-and-im-okay/

...... the Machinist School: "Everybody's got an ax to grind and we've got the grinder!!!"

Thanks Zac!!!!!!

Free For February - Chain Saw & Ax Sharpening

We had a big ice storm that broke the tops out of all the trees here in Northwest Arkansas. That means a lot of chain sawing is going on. Of course, a number of the elderly & otherwise unable to chop their way out of their yard are dependent on others to help out.
That's where it is handy to be a machinist!
The high school football teams are out carrying tree branches to make piles. Whoever has a chainsaw is cutting the branches into manageable sized pieces.
The Machinist School just sits inside by the heater, sharpening axes, hatchets, and chain saw chains.

Machinist School - How Hard Can It Be?

Measuring hardness is a trade unto itself. At a machinist school, students learn to measure hardness for a couple of reasons - to determine what type of cutting tool to use, to determine if an object is hard enough to perform properly.
For a cutting tool to work properly, it must be harder than the object being cut. If you have butter in a freezer, you could remove it from the freezer. Then, using a pocket knife, you could carve the butter into the shape of a knife. You would have a genuine butter knife. You could use the butter knife to cut and spread soft butter that had been sitting on the kitchen table for a while.
In a similar fashion, hard steel drill bits will cut into a piece of soft steel. To cut a piece of hard steel, one needs a cutting tool that is harder than the hard steel. Aluminum Oxide is harder than hard steel. Aluminum Oxide is a ceramic product often used to cut hard steel.
Sometimes a piece of steel is too hard. When a piece of steel is too hard, it is brittle and easily broken (simply by dropping it on the floor). Other times a piece of steel is too soft. When steel is soft, it is not very wear resistant. A knife made of soft steel would become dull quickly. Springs are medium hardness or above. Springs are hard enough to be wear resistant yet flexible enough to bend. (A spring that is too soft bends and does not "spring" back.)
One way to test hardness is to bend an object. If it fractures, it was hard. If it bends and springs back, it is somewhat hard. If it bends and stays bent, it is relatively soft. (If you bang your head against a piece of soft steel, you will find that soft steel is much harder than your head.)
Maybe it reminds you of "Goldilocks and the Three Bears" ..... "this bed is too hard, this bed is too soft, this bed is just right!" Of course, she wasn't talking about the bed of the lathe.
- And the three bears were not machinists!