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Prosock Machine Shop Talk

April 14, 2009

Prosock Machine featured in Cutting Tool Engineering Magazine

Recently, Bill Kennedy of Cutting Tool Engineering magazine interviewed our shop Foreman, Claude Kennedy, for his monthly piece called, “Part Time.”  Bill asked Claude to describe a particularly challenging CNC machined part that would be an example of our long line of success stories.  Here’s the article:

Holding Firm

John Prosock Machine, Inc. is a Quakertown, Pa., job shop that handles prototype machining as well as production and assembly jobs. Founded in 1982, the shop today has 10 mills, 13 lathes, and about 30 employees. Typical production runs range from 100 to 2,000 pieces, and the shop serves a wide range of customers; “we pretty much do anything,” said plant manager Claude Farrington, “medical work, driveline components, heavy equipment, parts for remote-control cars, you name it.” The shop machines a variety of materials including common steels and aluminums as well as plastics, titanium, and other exotic alloys.

Describing the machining of a prototype aluminum trunion housing for a powerboat steering system, Farrington said the actual machining of the complex-appearing part was not too difficult; “it was a matter of trying to figure out how to hold it.”

The roughly 11 ½”-long, 5 ½”-wide housing was intended to be mounted on a boat’s transom and house an electronic linear actuator. It is part of a system designed to provide instant steering response when activated by controls at the helm, eliminating the slow reactions of a cable system.

Prosock Machine received a DXF file from its customer and loaded it into the shop’s Mastercam CAM package to program milling operations. Lathe work was programmed at the machine.

The housing was machined from a 12″ x 6″ x 3 ½” 6061T6 aluminum block. It was clamped with the long dimension standing vertical in a Kurt vise with aluminum soft jaws on an Excel 810 VMC. One end of the finished housing would feature a single 1.850″-dia., 3.850″-long boss, but to start, two identical bosses were machined side-by-side. “We machined two so that when we flipped it over we could use them to align the part in the vise. Later we cut the one off that we didn’t need,” Farrington said.

The twin bosses were machined with a 1 ½”-dia. HSS endmill, run at 3,000 rpm and a 30 ipm feed rate, taking a 4″ length of cut. Farrington described the toolpath as “a figure 8 around the bosses,” stepping down 0.200″ on each pass.

Then the housing was flipped over in the vise and one of the bosses was located against a stop. On the other end of the finished housing would be two bosses that were not identical, being of different diameters and offset from each other by 70˚. One boss, in line with a boss machined earlier, was 2.100″ in diameter. The other boss was 1.514″-dia. Because this second set of bosses were closer together than the first pair, smaller endmills were used to machine them. The bosses were roughed with a 7/8″-dia. HSS hogmill and finished with a ¾”-dia. HSS endmill, both run at 1,200 rpm and 10 ipm with a 4″ loc. The two bosses were 1.360″ long, but one was set back (x “?) deeper in the part than the other.

Water-soluble coolant was applied throughout the machining process. Farrington described the HSS tools the shop employs as “generic,” and said all the solid-carbide tools it uses are from Mill Monster, while inserted milling and turning tools are from Kennametal.

When milling of the second set of bosses was complete, the smaller diameter one was drilled and reamed. A 1 1/16″-dia. HSS drill, run at 600 rpm and 4 ipm feed and pecking each 0.200″, drilled to a depth of 7.7″. As the tool pecked in and out of the workpiece, flood coolant from the spindle cleared the chips from the hole. A 1.103″-dia. reamer then finished the hole to a tolerance of +/- 0.0004″. At this point, the housing was removed from the mill and the extra boss created in the first operation was cut off with a band saw, leaving a short stub to be faced off later.

Next, the part was clamped horizontally in the vise and a 3″-dia. shell mill, run at 2,500 rpm and 20 ipm, face milled the housing to height of the next feature, a 3.5″-wide, 2.7″-long, 0.72″-deep pocket that would hold the actuator electronics. A ½”-dia. carbide endmill run at 3,500 rpm and 25 ipm, roughed out the pocket, leaving 0.050″ extra stock on the sides and 0.010″ on the floor. Then a ¼”-dia. carbide endmill finished the side profiles and bottom. A very small pocket in the bottom of the larger feature required the application of a 1/32″-dia. carbide endmill. Outside each corner of the pocket a hole was drilled 0.433″ deep with a 0.114″-dia.(?) drill, and tapped with an M3.5 x 0.6 tap.

The next operation involved milling the back of the housing. The part was flipped over in the vise, the 3″-dia. shell mill faced away excess material, and a ½”-dia. carbide endmill roughed and finished the details. The sharp edges of a lug created in the operation then were rounded with a radius mill.

Next, the housing was moved to a Eurotech turning center for turning, facing, and boring. With the 2.100″-dia. boss clamped in the chuck, the (now) single 1.850″-dia. boss on the other end of the part was turned down to a 1.765″ diameter for a length of 1.653″, using a DNMG 431 insert run at 700 rpm and a feed rate of 0.008 ipr. The same tool then faced off the remaining stub of the extra boss removed earlier. Farrington said the eccentric shape of the part posed no problem in the lathe; “It was a pretty good size diameter to hold on to, and we didn’t spin it at very high rpm.” A NTF2R threading insert then cut an M45 x 1.5 thread at the end of the boss.

Next, a 1-5/16″-dia. drill, employed at 400 rpm and 0.010 ipr with a 0.250″ peck cycle, drilled the boss out to a depth of 9.665″. A 1″-dia. KMT boring bar run at 500 rpm and 0.007 ipr finished the bore to a diameter of 1.37″, +/- 0.002″.

The part then was turned end for end in the lathe and chucked on the 1.850″-dia. boss, behind the thread. A 13/16″-dia. drill made a 2 ¼”-deep hole in the 2.100″-dia. boss at 500 rpm and 0.005 ipr, employing a 0.250″ peck. Then a 5/8″-dia. boring bar created a chamfer and a counterbore in the front end of the hole, and behind that cut a bearing diameter of 1.0004″, +/- 0.0004″.

For the final operation, the housing was clamped horizontally in a Haas indexer mounted on the table of the Excel VMC, again held on the 1.850″-dia. boss. A ½”-dia. carbide endmill, run at 2,000 rpm and 18 ipm, milled a series of lengthwise flats, positioned via the indexer at 10˚ intervals. Then the same endmill circular-interpolated two 0.775″-dia., 0.354″-deep counterbores in the end of the 2.100″-dia. boss. After machining, the housing received a 0.005″ – 0.010″ thick blue anodized coating.

Farrington said that total machining time for each part was roughly 1½ hours. He termed this job a typical small volume (“The customer wanted three, we made five”) prototype job, involving ongoing consultation with the customer’s engineers as the design evolved during the prototyping process.

For more information about John Prosock Machine, Inc., call (215) 804-0321 or visit

February 25, 2009

The 5th Annual Lean, Six Sigma & Business Improvement Summit will take place in Chicago, June 23 – June 26, 2009

I think all of us that are in manufacturing are looking for ways to stand strong during these tough times.  As a CNC mill and lathe shop we are looking for ways to cut cost and increase efficiency.  It’s one thing to create tight tolerance machined parts, but this must be complimented with a creative strategy of navigating through the radical change in how our business will now need to function in the new era we are in.  It can’t be business as usual.  Just as airplanes can’t fly without proper aerodynamics, business – especially machine shops – can’t sustain flight in business without a resdesign and a new phylosophy.

The upcoming Lean & Sixth Sigma Summit may indeed provide answers for us all.
Book now for the event that helps you buck the economic slowdown trend and ensure your company’s costs remain stable – or fall
WCBF’s 5th Annual Lean & Six Sigma Summit gives you the unique opportunity to confront the fundamental challenges for the integration, sustainability and expansion of Lean and Six Sigma as a combined approach of performance excellence, business growth and innovation. Over 200 of the globe’s most prominent Lean Six Sigma practitioners, representing a variety of industries are preparing to gather in Chicago to share their experience, knowledge and wisdom with you. Giving you an unprecedented opportunity to learn from the likes of Wal-Mart, Motorola, Johnson and Johnson, BMW, General Cable, Baxter Bioscience and many more.
No matter where you are in your Lean Six Sigma initiatives – whether you are one of the early adopters whose Lean Six Sigma strategies are central to the overall business plan, or new to the whole concept this is the single most important event of the year. As you will see when you come to examine the Summit agenda, we are examining Lean Six Sigma from the viewpoint of key industries that find it the most valuable, including healthcare, pharmaceuticals, government, and services – and showing how to apply those best practices to other verticals.
Join your peers at this landmark event that brings you face to face with world class experts to discuss the still-untapped potential – and challenges of Lean and Six Sigma.
Benchmark and learn from practical experiences:
• More than 30 case studies
• 6+ interactive panel discussions
• 20+ dedicated tracks
• 13 Pre and Post Summit hands-on workshops
ALL LEVELS COVERED – Beginners, Intermediate and Advanced Practitioners
ALL INDUSTRIES COVERED – Manufacturing, Service and Transactional Environments
If you would like a reminder nearer the event please click here.
Or just print this page for future reference.
Based on the enormous success of WCBF’s Six Sigma event series to date, it is expected that this will be the largest senior-level conference to focus on Lean Six Sigma & Business Improvement. Nowhere else will you find such an exceptional array of speakers and organizations willing to share their experience with you.
Pick One. If you plan on attending just one Lean, Six Sigma & Business Improvement conference, then this is the one to select. WCBF currently averages over 200+ senior-level attendees at its Six Sigma Conferences. This is the highest number of senior-level attendees per a Six Sigma niche focussed conference than any other organization.
Book now and save up to $575.
Hosting The Global Six Sigma and Business Improvement Awards
The Global Six Sigma and Business Improvement Awards are given to the most outstanding organizational achievements through the deployment of business improvement programs.
The focus of this elite awards program is to demonstrate to the global business community the real results and excellence which organizations achieve through the successful deployment of Six Sigma and other business excellence programs.
After extensive reviews by an independent panel, the Lean Six Sigma CEO of the Year Award 2009 will be presented to Karen Strauss, CEO, Masco Builder Cabinet Group. Karen Strauss will accept the Award on the morning of June 24th at the Lean & Six Sigma Summit, including a short acceptance speech. See our testimonials for further evidence of the quality of our events.
Get your personally signed copy of books by leading business authors to takeaway at the exclusive book signings during the Summit including:
Books by Thomas Pyzdek:
The Six Sigma Handbook
Quality Engineering Handbook
The Handbook for Quality Management
Books by Pete Pande:
The Six Sigma Leader
The Six Sigma Way
Implementing Six Sigma: Smarter Solutions Using Statistical Methods: Second Edition. By Forrest W. Breyfogle
Pull Thinking®: Harness the Power of Pull to Fuel Growth and Ignite Performance by Aligning People, Culture and Purpose. By Kenneth E. Meyer
Testimonials from our recent six sigma events:
“Thank you for such a great Conference. Over the years, I have attended 25+ Six Sigma Conferences and I have never participated in one better. We appreciate you and your team’s hard work!”
Dr Neal Mackertich, Founder, Raytheon Six Sigma Institute, RAYTHEON
“As a new deployment leader, I attended three Six Sigma conferences last year, and yours was by far the best! I found the sessions to be varied and informative, and they were supplemented by opportunities to mingle with other participants and industry specialists. I look forward to making the WCBF conference an annual event!”
Linda Bowyer, VP Service Quality, TD Canada Trust
“The orchestration of the key leaders – CEO, CIO, VP – to tell their success stories; the sprinkling of “new and refreshing thinking” and the caliber of the attendees made this one of the most outstanding learning events of the past 2-3 years.”
Wanda Sturm, SigmaPlus Engagement, HP
“The event was first class — outstanding speakers (especially Jim Collins), exhibits, and meals. It was a great week!”
Stephen J. Wittig, Vice President Six Sigma, QualityCabinets/Merillat
“WCBF’s Global Six Sigma Summit offers a great opportunity to meet thought leaders in a variety of industries. The presentations are first-rate, and the “sideline” interactions are incredibly valuable to me.”
Mike Richman, Publisher, Quality Digest
“The conference attracted a high percentage of organization leaders as well as Six Sigma practitioners providing an excellent opportunity for sharing/networking. You were successful in attracting several high level people and engaging speakers that brought this summit to a higher level than similar ones.”
Don Baker, Rochester Institute for Technology
“Vijay Bajaj and his staff at WCBF consistently produce premier, high-value conferences related to Six Sigma, Lean, Design for Six Sigma and Innovation. WCBFЃfs attention-to-detail, adherence to sound ethical standards, high degree of collaboration and responsiveness, commitment to post-conference follow-up and focus on maintaining long-term, excellent business relationships sets it apart from other conference organizers. Their ongoing commitment to objectively gauging the needs of their diverse, world-wide customer base and quickly responding to changing market trends enhances WCBFЃfs ability to attract the most talent speakers in their respective fields. For these reasons, Air Academy strongly supports and thanks WCBF for their contributions.”
Lee Pollock, Senior VP, Director of Lean Sigma Programs, Air Academy Associates
“The summit was outstanding Ѓ] great networking and process improvement sharing!”
Wayne R. Potter, Electrical Value Stream Leader Process Excellence, Northrop Grumman Corporation
“I always enjoy networking with professionals leading in problem solving. This year’s conference was a good sharing of lessons learned and fresh practical ideas.”
Rick Morrow, Director of Continuous Improvement, United Airlines
“I’ve attended six sigma conferences over the past few years and this WCBF event was the best. I look forward to the next WCBF six sigma conference.”
Chris Kargula, DFSS Engineering Manager, Cooper Standard
“The WCBF Global Six Sigma Summit and Awards Conference was our most successful marketing event for 2007. This was largely the result of the personal interest WCBF staff took in finding ways to optimize our visibility and facilitate contact with key prospects.”
Wayne Caccamo, VP Marketing, Instantis
“The conference last week was fantastic. Jim Collins and Mikel Harry were outstanding and provided unique perspectives for the profession. The mix of track speakers was also the best I have seen.”
Paul Hesselschwerdt, President, Global Partners Inc
“A Summit very well organized where the aim of the program is the content and the real research of best Practices. It was a hard job as an Awards Judge due to the real top level of competitors and their great results.”
Fabrizio Majorana, Deputy CEO, UniCredit
“I am extremely pleased with BMO’s breakthrough performance in Lean Six Sigma deployment across Product Operations in North America. Winning two prestigious Global Six Sigma Awards has validated the hard work and dedication of our people, and significantly stimulated interest from other BMO businesses to leverage Lean Six Sigma for delivering strategic initiatives.”
Richard Lam, Deployment Leader, Quality & Productivity Management Office, BMO Financial Group

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