Back to Basics: Micrometers

By Jim Tapp
GOODSON Tech Services Manager

We're going to back up a little this month to something that's an essential skill to have in engine machining or any kind of machining for that matter. You MUST know how to operate and read and care for a micrometer. It sounds, elementary, I know, but sometimes it pays to go back to the basics for a quick review. For the sake of this article, I'll be talking about an inch micrometer. For more on using metric micrometers, check out the Goodson Technical Library.

Most people think of an outside micrometer when they hear the term "micrometer". An "outside micrometer" is one that measures the outside of something such as diameter, length, thickness. But there are other types of micrometers, including depth micrometers and inside micrometers. As the names imply, they measure depth and the inside diameters, respectively. Often other tools (such as bore gauges) are used with micrometers to determine sizes so knowing how to read the micrometer is absolutely necessary.

How to Read a Micrometer

A micrometer is a measuring gauge operated by a screw with 40 threads per inch. This means that one complete revolution of the screw advances one thread exactly or one-fortieth of an inch. 1/40” equals 25 thousandths of an inch or 0.025". The beveled edge of the thimble is divided into 25 equal parts. Each line equals 1/25 of .025” or .001” (one thousandths of an inch). One complete revolution of the thimble therefore equals .025” or one line on the barrel scale. With that in mind, here's a quick quiz: What is the reading shown in the picture to the right? For a larger version of the image, click on the picture. A new window will open with an enlarged view. >>Get the answer and read the rest of the article >>

Chemical Concentration essential to performance

By Chris Jensen,
GOODSON Techxpert™

We're back talking about cleaning again. We continue to get calls from shops wondering why their cleaning solution isn't working as advertised.

The first question we'll ask is, "What's your mix ratio?" Vitrually every cleaning solution will have an optimum mix ratio of chemical to water. Our recommendation is that you start on the weak side and see how that cleans for you.

Let's say you're using our D-AL50 Detergent for non-ferrous metals. The mix ratio is 1/4 pound per 1 gallon of water. Start out just a little under that and work your way up.

This is NOT an instance where a little more will make it better. An overly strong cleaning solution won't work any better than one that's too weak. Remember too, that if the solution is a little weak, you can add to it, but if it's too strong, you're going to have to start from scratch (and you've just wasted your time and chemicals and, ultimately, your money).

We recommend using pH test strips (HT-PH) to check the concentration. Your target for most cleaning solutions is a pH of 11.5 to 12.5.

For more cleaning tips, check out the Goodson Tech Library.

Microbiostat controls fungus and bacteria in coolant reservoirs

Jim Tapp,
GOODSON Tech Services Manager

We talked last time about the odor that can sometimes take over the shop as the temperatures warm up. As you probably know, that odor is caused by the bacteria and fungus that are living in your coolant.

That's why I strongly recommend using Microbiostat to keep the stench to a minimum. Now, don't get me wrong, this is not a cover-up or fix-all. You're still going to have to perform basic maintenance and clean the coolant sump, the hoses, etc. Once your machine is clean, you can use the microbiostat to keep the little beasties (the ones that stink) from multiplying again.

You use 1 ounce of microbiostat per 10 gallons of coolant about every 10 days so this 20 ounce bottle should easily get you through the summer.

Want to know more?
Download the product's MSDS or visit our online store for more details.

Dates to remember:

April 20-23 , 2009
2009 SAE World Congress
Focus of this conference is "Racing to Green Mobility." For more information or to register, visit www.sae.org/events
Cobo Center, Detroit, MI

September, 2009
PERA Fall Technical Conference
The '09 Fall Conference will be held in Savannah, Georgia. As details become available, we'll pass them along.
Find out more

November 3-6 , 2009
SEMA Show 2009
The SEMA Show is the premier automotive specialty products trade event in the world. In addition, the SEMA Show provides attendees with educational seminars, product demonstrations, special events, networking opportunities and more… Las Vegas, Nevada Find out more

December 10-12, 2009
22nd Annual PRI Trade Show
Don’t miss the three biggest business days in motorsports when the worldwide racing industry gathers in Orlando, December 10-12, 2009, for the 22nd Annual Performance Racing Industry Trade Show. Orlando, Florida
Find out more