Tuesday, August 25, 2009

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!

Monday, June 15, 2009

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.

Saturday, April 11, 2009

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.

Saturday, March 21, 2009

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.

Sunday, March 8, 2009

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?

Monday, February 23, 2009

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!

Wednesday, February 18, 2009

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!!!!!!

Friday, February 13, 2009

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.

Thursday, January 1, 2009

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!

Sunday, November 30, 2008

Educational Career Training School

Some folks go to machinist school for career training. Other folks go to machinist school because they like to make things. Sometimes women go to machinist school because the trade is male dominated. (Either they want to meet guys or to show folks they can do what the guys do.) Other people go to machinist school because their parents say "Either move out or go to school." (They figure machinist school is an easier or more fun education than accounting.)
At least once, a hispanic political activist went to machinist school in hopes of finding discrimination against hispanics. (Instead he learned a trade!) Others go to machinist school because of a free opportunity - they got a scholarship, they got laid off at work and the unemployment office is sending them to school, they are in some kind of disadvantaged (disabled, minority, etc) status that receives educational benefits, or maybe they are using veterans educational benefits. Another group is the offspring of machinists, going to school to follow the trade of their ancestors. If you want to learn to be a machinist (person that makes things using machine tools) you might go to a machinist school.

Thursday, November 20, 2008

Winter??? 30 degrees ........

Degrees can be pretty confusing. A circle can be divided, sort of like a pie, into pieces. If the circle is divided into 360 pieces, the pie is said to be divided into 360 degrees.
Why would this be?
Some folks say it is because of donuts. Donuts are round - they are circular.
Donuts are round circles cooked in hot oil.
The oil is heated to 360 degrees fahrenheit. Thus to keep people from being confused about angular degrees and fahrenheit degrees, donuts have both kinds of degrees equal to each other.
When you stop to think about it, 360 degrees is 30 degrees a month.
That brings up the question, "What is 30 degrees?"
For the answer, you'll need a yardstick (a ruler that is 36 inches looooooonnnnnng).
You will also need a piece of tape or some other nondestructive method to place a mark on the wall.
Step one: from the floor, measure vertically up the wall .... place a piece or tape 18 inches up from the floor.
Step two: lay the yardstick on the floor, perpendicular to (sticking straight out from) the wall.
Step three: the end of the yardsitck against the wall ..... slide it up the wall to the tape/mark
(note: the other end of the yardstick will drag across the floor toward the wall)
Step 4: Announce with glee,"Look everybody, I have invented the 30 degree angle!!!! The yardstick is at a 30 degree angle to the floor. A hotwheels car, driving up the yardstick, would be ascending a 30 degree inclined plane .......... Shazaam, Shazaam, Shazaam!"

The 30 degree angle is a marvelous angle. Now for the test .....
What if you didn't have a yardstick! How far would you have to measure up the wall to make a 30 degree angle if you only had a 12 inch ruler? (ans. 6 inches)
What if you had a 2 foot ruler? (ans. 1 foot)
Can you make a general rule for how far to measure up the wall to create a 30 degree angle?
............. "Half the length of the ruler", you say? Wow! That's right!
What if you took off your belt and found it to be 32 inches long. What if you stretched it from the floor to a point 16 inches up the wall. What if the belt was the same color as automobile tires?
(ans. you'd have a 30 degree blackbelt ..... you'd be a marshall art guy like Matt Dillon)

When people ask, "How do I learn to be a machinist?" ......... tell 'em, "Well, for one thing, you'd better learn how to make a 30 degree angle AND how hot to heat oil to make donuts."

Monday, November 10, 2008

Model Making Involves Machining

Yet another machining activity is making scale models of actual machines.
The "For More Info" Link to Machine Shop Wizard of the World is one such individual.

For Chevy fans, here's one to please:
http://www.moyermade.com/chevyV8.html

Click the picture at the bottom of the link to see the Chevy 327 model engine run.

Sunday, November 9, 2008

The Heart of the Machinist School

Here's a link to Grit In the Gears ......
He's got a twisted heart.
See it live ..... (pronounced with a long I or short i?) ....

http://gritinthegears.blogspot.com/2008/11/heart-gears.html

While people say, "To be a machinist, your heart has to be in it," in truth, it is considered good practice to keep organs and body parts out of the machinery.

Saturday, November 8, 2008

Machinist School Textbook

To download a great machinist school text about forging and the engine lathe see the following link:

http://books.google.com/books?id=iD5IAAAAIAAJ&pg=PA193&lpg=PA193&dq=lathe+cross+slide+thread+stop&source=web&ots=OBgpj8JkSs&sig=S95bUOsIZ8x3sHWSFRGnPoVcPcQ&hl=en&sa=X&oi=book_result&resnum=7&ct=result#PPP1,M1

Machine Tool Operation - Part I - The Lathe Bench Work and Work at the Forge by Henry D. Burghardt is a 1919 text whose copyright has expired and is now available as a free digitized download from Google.

Maybe this IS planet Earth ..... maybe we ARE all in this together .... maybe sharing knowledge IS OK .....

Saturday, November 1, 2008

Micrometer - Mike for Short

To learn to be a machinist, one has to learn about the tools of the trade. One of the tools is a micrometer. The micrometer is used to measure distance. The distance is determined in small increments, parts of an inch ..... smaller than half an inch .... smaller than 1/4 of an inch .... smaller than 1/8 of an inch ..... smaller than 1/16 of an inch .......
The micrometer measures in increments of 1/1,000 of an inch (about half the thickness of a human hair).
I showed my little sister a micrometer. "Charlotte, look at the micrometer," I said.
I could tell by the astonishment in her face that she was impressed.
Then she exclaimed,"Nuh-uh ..... no way! That's not YOUR crometer. That's Daddy's crometer!"