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Speaking of Precision

Speaking of Precision is a knowledge preservation and thought leadership blog covering the precision machining industry, its materials and services. With over 36 years of hands on experience in steelmaking, manufacturing, quality, and management, Miles Free (Milo) Director of Industry Research and Technology at PMPA helps answer "How?" "With what?" and occasionally "Really?"

Grinding Advice You Probably Didn’t Know

Posted August 19, 2014 10:30 AM by Milo
Pathfinder Tags: finger cots gloves grinding tips

Our post on No Gloves When Working on Grinders has prompted a number of responses.

Here are some additional reasons why you should not even need gloves when working on grinders and grinding machines.

Issue: "There are sharp edges or burrs that will cut me if I hold the part. The grinding will be to remove the burrs."

Response: Use a file to knock down the burrs so that you can safely hold the part for grinding. Or use leather finger cots to grip the part for grinding.

We permitted these for use on belt grinders for holding small parts.

Issue: "The part gets too hot to hold."

Response: Then you are grinding wrong. Here is a list of some of the things that can go wrong by letting the heat of grinding get out of control:

  • Remove the temper from Steel. Especially on tools, loss of temper means loss of tool hardness and edge life. A drop from Rc63 to about Rc48 for a couple of tenths (0.0002-0.0005) can contribute to side wear and edge failure.
  • Crazing or checking on Carbide can be caused by burning during grinding.
  • Work Hardening. Overly shiny surfaces are usually the clue that work hardening has occurred.
  • Creation of untempered martensite.

Untempered martensite can be formed in high carbon and alloy steels by getting high surface temperature from grinding- red heat- then quenching in water.

  • Untempered martensite is very brittle and reduces toughness.
  • Keeping the work cool continuously while grinding is an important aspect of preventing damage to work, the wheel, and injury from occurring to the worker. Hogging off material and infrequently quenching is a great way to destroy a tool by grinding
  • Water needs to be plentiful to absorb the heat from grinding, and frequently used to reduce heat buildup in the work.
  • Take multiple small passes and cool in between in a large bath of water while grinding to minimize heat build up.

Of course, wearing the required PPE, making sure the grinding wheel is properly dressed, all guards are in place and properly adjusted are also key to safe grinding in our shops.

Bottom line: If the work is too hot for your fingers, it may be approaching the danger zone regarding loss of mechanical properties and function in end use.

8 comments; last comment on 08/20/2014
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Gloves and Grinders – UNSAFE OSHA

Posted August 15, 2014 10:00 AM by Milo
Pathfinder Tags: gloves grinders osha Tools

If there is a worse combination than grinders and gloves, I don't know what it is, except perhaps for gloves and a drill.

We posted a really cool video on our career blog about making a light saber sword here. But we were shocked to see the guys in the video wearing heavy leather gloves while working with grinders.

Never wear gloves with grinders. Or operate grinders with guards removed.

By "grinders," we mean abrasive belt grinders, bench grinders, pedestal grinders, surface grinders, and also abrasive cutoff machines.

No Gloves!

Sanders, polishers, and buffers that involve rotating wheels or transversing motion are also included in this classification for the purposes of hazard analysis.

Here are 6 reasons to not wear/not permit the wearing of gloves while working with Grinders or Grinding Machines

  • Amputations
  • General duty of employer to provide a workplace free of recognized hazards
  • Gloves can catch on rotating equipment and pull operators hands into the equipment
  • Rotation of grinding wheels is at high RPM's
  • Operator cannot get hand out of glove when it catches
  • Equipment horsepower and machine material properties exceed those of the operators flesh

We did a quick calculation and a 12″ grinding wheel and 3600 rpm and arrived at a speed on the periphery of 120 miles per hour.

No time to react.

More info on preventing amputations from OSHA


Editor's Note: CR4 would like to thank Milo for sharing this blog entry, which you can finish reading here.

38 comments; last comment on 08/20/2014
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Carbon Steel Without Manganese?

Posted August 05, 2014 11:00 AM by Milo
Pathfinder Tags: manganese manufacturing roll steel

Manganese ties up Sulfur before it can chemically combine with Iron to form Iron Pyrite. Iron Pyrite occurs at grain boundaries and leads to hot shortness (brittle behavior) at rolling temperatures.

More than fools gold, Iron Pyrite can prevent steel from being hot worked by inducing "hot shortness."

We saw that several people found our blog with the search term "Carbon Steel Without Manganese."

So we'll take this opportunity to answer that.

We have already written about 5 Facts about Manganese in Steel which explains the contributions of Manganese to a steel's properties.

But lets answer the question - is there a Carbon Steel without Manganese?

The answer to that is No.

Here is the primary reason why. Iron Pyrite.

There are always small amounts of sulfur in steel, and Sulfur combines with the iron in the steel to form Iron Pyrite. Iron Pyrite is also known as iron sulfide, though a more descriptive name might be Iron persulfide.

Regardless, this material is formed as sulfur in the melt reacts with iron , and this material segregates at grain boundaries., causing intergranular brittleness. This causes it to break, rather than behave in a ductile fashion and reduce under the pressure of the rolls.

By adding Manganese to the melt, Manganese preferentially ties up the available sulfur, forming manganese sulfides. this prevents the formation of iron pyrites in the grain boundaries, preserving the ductility of the steel at rolling temperatures.

That is why every steel that we have encountered contains enough Manganese to react with the sulfur in the melt.

Steel without Manganese? Nope, I've never encountered it. And that is a good thing!

Photo credit


Editor's Note: CR4 would like to thank Milo for sharing this blog entry, which you can finish reading here.

7 comments; last comment on 08/08/2014
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How Does Your State Rank for Manufacturing?

Posted July 29, 2014 10:30 AM by Milo
Pathfinder Tags: census manufacturing map

The 2014 Connexus Indiana Manufacturing and Logistics report is a clear, easy to understand 6 page document with graphs and a single Data table report card to give you great insights into the "state of Manufacturing in your state."

We were pleased to find a treasure trove of state by state data on Manufacturing at the 2014 Manufacturing and Logistics report prepared by Connexus Indiana, CBER Ball State Muncie Indiana.

Think of this as a useful piece of "Business Intelligence" to confirm your feelings about your particular states Manufacturing performance.

Manufacturing Health

From the report:

"Manufacturing is the production of both consumer durable goods (e.g. automobiles, electronics, and home appliances that last for years) and consumer non-durable goods (e.g. clothing, processed foods, and other goods that are consumed after use).

To measure manufacturing industry health, we include three variables: the share of total income earned by manufacturing employees in each state, the wage premium paid to manufacturing workers relative to the other states' employees, and the share of manufacturing employment per capita.

Sources: U.S. Department of the Census and Bureau of Economic Analysis. "

On this site you will also find indicators grading states for:

  • Human Capital,
  • Worker Benefit Costs,
  • Tax Climate,
  • Expected Fiscal Liability Gap,
  • Global Reach,
  • Sector Diversification,
  • Productivity and Innovation
  • And Logistics.

Here's that link: 2014 Manufacturing and Logistics report

About Ball State CBER

The Center for Business and Economic Research (CBER) is an economic policy and forecasting research center at Ball State University. In addition to its analysis and data delivery offerings, CBER organizes the annual Indiana Economic Outlook and quarterly meetings of the Business Roundtable.

Center for Business and Economic Research

2000 W. University Ave. (WB 149)Muncie, IN 47306765-285-5926http://www.bsu.edu/cber


Editor's Note: CR4 would like to thank Milo for sharing this blog entry, which you can finish reading here.

18 comments; last comment on 08/14/2014
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It Takes a Factory to Make a Manufacturer

Posted July 18, 2014 11:00 AM by Milo
Pathfinder Tags: factory manufacturing

How can you call yourself a manufacturer if you don't manufacture anything?

If they don't really manufacture, why should we call them manufacturers?

The Economic Classification Policy Committee (ECPC) of the Census Bureau is considering changing the definition of manufacturing to include "Factoryless Goods Producers" (FGP's) as part of an update to the North American Industry Classification System (NAICS) 2017.

They say "A factoryless Goods Producer (FGP) establishment outsources all of the transformation steps traditionally considered manufacturing (i.e., the actual physical chemical or mechanical transformation of inputs into new outputs), but undertakes all of the entrepreneurial steps and arranges for all required capital, labor, and material inputs required to make a good." Factoryless Goods Producer Fact Sheet

Buying stuff from other manufacturers isn't manufacturing, it's wholesale trade.

If an establishment doesn't actually manufacture something, why should it be classified as a manufacturer?

If a company doesn't have a factory and means of transforming inputs into goods, why should that be classified as manufacturing?

If a firm doesn't employ workers to transform inputs into finished goods, why is that manufacturing?

We submitted our comments on this issue.

You can too go to http://www.regulations.gov then

  • Type in "NAICS for 2017″ in quotes in the search box labeled 'Rules, Comments, Adjudications or Supporting Documents'
  • Click search;
  • Click the Comment Now!
  • Follow instructions for submitting your comments.

There are many reasons to oppose the creation of a type of manufactuirer called a Factoryless Goods producer. I put a bunch of them in my comments.

But you only have to ask one logical question, really- How can you call yourself a manufacturer if you don't manufacture anything?

And how does that help create statistics we can use if manufacturer no longer means "company that manufactures?"

Photo credit:

We've covered this before:

http://pmpaspeakingofprecision.com/2014/03/17/manufacturing-defined-making-things/


Editor's Note: CR4 would like to thank Milo for sharing this blog entry, which you can finish reading here.

8 comments; last comment on 08/07/2014
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Time to Review the Precautions for Heat Stress

Posted July 11, 2014 10:30 AM by Milo
Pathfinder Tags: heat osha

I was reminded of the possibility of heat stress in our shops when I started the car the other day.

Early in my career in the blast furnace casthouse and on the ore docks staying safe from the effects of high heat was a daily event.

On top of the coke plant batteries it was a minute by minute struggle.

While we do not face these same levels of heat in our precision machining shops per se, the summer can bring high, unaccustomed temperatures. Temps of over 100 degrees are easily attained in places with high solar gain and stagnant air.

Unloading trucks outside or doing external work on roofs or even landscaping can put even the most fit worker into some form of heat stress if precautions have not been taken.

Here is the OSHA pocket card for Heat Stress Awareness

Click here for link to the PDF


Editor's Note: CR4 would like to thank Milo for sharing this blog entry, which you can finish reading here.

5 comments; last comment on 07/13/2014
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