CR4 - The Engineer's Place for News and Discussion®
Login | Register for Engineering Community (CR4)

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?"

Amputation Hazard Follow Up: Logan Clutch Door Interlock

Posted September 22, 2015 2:00 PM by Milo
Pathfinder Tags: amputation hazard machining osha

Our recent post on the latest OSHA Emphasis program on Amputations brought us a comment from Michael Krizmanich at PMPA Technical Member Logan Clutch about avoiding violations (and potential amputations) through door interlocks. "Some screw machine customers use the Logan Clutch control for machine guarding. The CS2001 Microprocessor Control has two pairs of inputs for two Door Interlock Switches."

As staff providing member assistance to companies when OSHA visits and cites guarding, we have found that typically OSHA insists on door interlocks, despite the Kershaw Exemption which we have written about here.

So the Logan Cutch Door interlock is a potential solution to the OSHA identified guarding issue.

Door interlocks make the OSHA folks happy.

CS2001 Door Start Interrupt Switch Inputs: How They Work

The CS2001 Microprocessor Control has two pairs of inputs for two Door Interlock Switches. Each pair of is designed for one normally opened switch contact and one normally closed switch contact. The control senses both inputs together and has an override/defeat checking feature to monitor door input functionality.

CS2001 Safety Features & Safety Relay
The CS2001 Control has a stop circuit which integrates a Pilz Category 4, EN 954-1, model PNOZ X2.1 Safety Relay. The safety relay, provides dual-channel E-STOP with monitored manual reset. One channel of the Pilz Safety relay is connected to an output of the CS2001 microprocessor control. One channel of the Pilz Safety relay is connected in series to multiple, maintained contact, red mushroom head push buttons. A second separate contact of the red mushroom head buttons is wired in series into a CS2001 Microprocessor Control input. The reset input of the Pilz Safety relay is connected to an output of the CS2001 Microprocessor Control. All control power outputs to all external machine devices are wired thru the Pilz Safety Relay Safety Contacts.

Additional functionality included:

  • Stock Load Position Selector Switch
  • Thread Check Failure System
  • Short Part & Broken Tool Detectors
  • Stock Depletion Detector Inputs
  • Machine Lock-up Detection

Here's a link with more information:

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

1 comments; last comment on 09/22/2015
View comments

Twenty-Five Years of Software Success--Henning Software

Posted September 18, 2015 11:00 AM by Milo
Pathfinder Tags: machining manufacturing software

It's not every post that I write that I can start with a reference to DOS desktop computing, but in 1990 that was the engine for Henning Software's Job Estimating Software.

This is how we got our music in 1990 when Henning started writing job shop software.

After successfully creating job estimating software, Henning Software realized it would need to keep expanding their software offerings into a fully developed ERP system in order to grow in the market.

"At the time, most of ERP software available was minicomputer based and priced upwards of $50,000, which was too expensive for smaller shops," Mrs. Henning says, co-owner of Henning Software. "We thought we could make something better, but we needed more than job estimating software. We needed our software to manage all operational and accounting areas of a manufacturing business."

In their 25 years in the job shop manufacturing business, the Henning's and their company have been active participants and supporters of PMPA, especially through our technical conferences where, as likely as not, they are presenting on IT and leading edge technological developments.

Today, Henning Software's customer base spans all across the U.S. and Canada. And at PMPA conferences, many of the Henning's customers will be in attendance. Job shops, contract manufacturers, screw machine shops, tool and die shops, and metal fabricating companies are among the kinds of manufacturing companies that rely on Henning Software for their ERP, Estimating, and Accounting software needs.

For more information about Henning Software and their ERP solutions click here

Article in September issue of Production Machining on Henning Software Long Time Success

How do you remember the 1990's?

For some PMPA members, 1990 was when they first started managing their shop using Henning Software.

You do remember the 1990's right?

Discman photo courtesy wikimedia

Fashion photo credit

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

OSHA National Emphasis Program on Amputations Updated

Posted September 15, 2015 1:00 PM by Milo

"The intent of this NEP is to target workplaces with machinery and equipment that cause (or are capable of causing) amputations, while maximizing the Agency's inspection resources."

OSHA updates NEP for amputations.

OSHA recently issued an updated National Emphasis Program (NEP) on Amputations. The NEP has been in existence since 2006 and is targeted to industries with high numbers and rates of amputations.

In this latest update NAICS code 332710 Machine Shops and most other 332 NAICS code Categories are listed as Targets.

See Appendix C in the PDF

What else did we note when we looked at this?

-They will be asking for your DUNS Number

-They will be checking compliance on the new requirements for reporting work-related fatalities, hospitalizations, amputations, or losses of an eye.

Updated Directive

Change to Reporting requirements that went into effect January 1, 2015: Updated Employer Reporting Requirements 2015.

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

Heat Treat Colors of Steel Chart

Posted September 11, 2015 11:00 AM by Milo
Pathfinder Tags: chart heat treating machining steel

Our Temper Colors for Steel Chart Post remains very popular. So here is a chart of Heat Treat Colors for Steel.

Heat treat colors for steel by Temperature

These days pyrometers are affordable. But it is the mark of a craftsman to be able to tell temperature by eye, if only to validate the instrumentation (or suspect it!)

These colors were obtained from a 0.40 wt. % carbon, alloy steel, as seen through a furnace peep hole during average daylight conditions.

Temper Colors for Steel Chart

Art of the Craft

Knowledge Retention

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

4 comments; last comment on 09/14/2015
View comments

30 Potential Causes of Part Length Variation On Screw Machine Parts

Posted September 08, 2015 1:00 PM by Milo
Pathfinder Tags: machining part length variation

There are many different ways that part length can vary when using a cut-off tool on Multiple Spindle Automatic Screw Machines.

Here are some of the major reasons grouped into a rough classification by where the cause exists.

The Cut-off Tool itself

  • Tool is dull
  • Tool is improperly ground (point angle too large)
  • Tool loose / improperly inserted into holder
  • Tool Blade too thin
  • Cut-off tool hitting while in high speed
  • Cut off tool being hit by die head or chasers

The Cut-off Tool Holder

  • Tool holder itself is loose
  • Tool holder is hitting work spindle
  • Tool holder is hitting tool post
  • Tool holder is warped or bent
  • Tool holder is worn

The Work Spindle

  • Spindle has end play
  • Spindle has worn bearings
  • Spindle carrier has end play
  • Index Lock Pin Spring is broken
  • Finger holder not adjusted properly
  • Broken pins or fingers in finger holder
  • Feed tubes bent or beat up
  • Wrong stock feed cam- Overfeeding stock will cause bounce back from stock stop resulting in short part
  • Incorrect collet tension

The Cross Slide

  • Cross slide play
  • Cross slide loose
  • Cam is loose
  • Cut off cam too large causes too much feed
  • Cam Drum is loose

Other Tools

  • Stock pushed back into collet by drill (dull drill pushing stock rather than cutting chip)
  • Stock pushed back into collet by reamer
  • Face-off tool is loose
  • Face-off tool is dull
  • Face-off tool holder is loose
  • Die head pulling stock out of collet making part long

Part length can occasionally go awry when using cut-off tools on automatic screw machines.

This post lists over 30 reasons that I can think of- what did we miss?

Photo Credit- Acme Gridley Multiple Spindle Bar Machine Manual First Edition 1961 page C11.

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

2 comments; last comment on 09/15/2015
View comments

Metalworking Fluids: Learn How Latest Trends Will Impact Your Company

Posted September 04, 2015 11:00 AM by Milo
Pathfinder Tags: fluids machining metalworking

The 5th International Conference on Metal Removal Fluids will explore the latest trends and advances in the Metal Removal Fluids and Lubricants industry. And it will have a session focused on Impact of Regulations.

Topical Tracks include

  • Health and Safety Effects/Occupational Medicine
  • Exposure Measurement and Guidelines
  • Managing Metal Removal Fluids in the Plant Best Practices
  • Impact of Regulations
  • Practitioner Focus

PMPA is a sponsor of this conference and will be participating.

The conference is presented by ilma, STLE, and UEIL

If you have someone in your shop that is responsible for managing Metal Removal Fluids, handling the regulatory impacts of Metal Removal Fluids, assuring the use of best practices for Metal Removal Fluids, this conference will provide the latest intelligence.

Here is the link: 5th International Metal Removal Fluids Conference

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

Previous in Blog: It's Not One Thing  
Show all Blog Entries in this Blog