Recent Postings

If you are having difficulty manufacturing or burning small/thin rib electrodes or tapping electrodes, give copper-impregnated graphite a try. You still need to use the standard graphite machining conditions, but the copper that is infused into the material makes it easier to machine the electrode to form and prevent chipping during the milling/turning process. The copper also gives added rigidity to the graphite, thus reducing flexure of the electrode during orbiting. This flexure can cause uneven surface finishes and inaccurate cavities or parts. Copper-impregnated graphite is available from several manufacturers, including Poco, Toyo Tanso, Ibiden and others. For information on copper-impregnated graphite materials and applications, contact Single Source Technologies (SST) at www.singlesourcetech.com.

Makino in Auburn Hills, MI welcomes you to attend the Advanced Manufacturing and High-Precision Technology Expo. During this two day event on October 12 and 13, we will have seven EDM machines on display among a total of 17 machine tools. These EDMs will represent Makino’s diversity in the field, from the workhorse DUO-Series wire EDMs, to the ultra-precision UPJ2 horizontal WEDM. If its super fine finishes you require, especially in carbide and PCD materials, we will be demonstrating the new UPV-Series WEDMs that operate with oil instead of dielectric water.

Our newest sinker EDM, the EDAF-Series with ArcFree Technology, will be sporting the latest in on-board program generation, Makino Program Generator (MPG). The larger EDAF3 will be outfitted with our extremely precise Fine Hole option for drilling of holes as small as 11 micron, and L:D capabilities of over 100:1. At the pinnacle of accuracy for Makino sinker EDM technology are the EDAC1 and EDFH1. We will have an EDFH1 machine in our controlled environment room. This machine can be used as both a standard sinker and a precision EDM hole drill, just like our EDAF machines with Fine Hole option. The big difference is that the EDFH1 can achieve the finest of finishes and the smallest of details with ease.

It’s going to be one of the premier manufacturing technology events of 2011. If you’re in the Detroit area, stop in and see what Makino has to offer. Register now at www.makino.com/expo.

If you’re planning on attending imX next week at the Las Vegas Convention Center, I’d like to welcome you to stop by the Makino Experience Zone (#2348) to see the ArcFree Technology and fine-hole finishing capabilities of the EDAF2-FH sinker EDM, as well as the mirror-like surface finishing capabilities of the oil-dielectric based UPV series wire EDMs. Our skilled team of EDM engineers will be on hand to address your manufacturing challenges and discuss the latest solutions in sinker and wire EDM technologies.

You can also “learn more to earn more” at Makino’s micromachining learning lab, where my colleague, John Bradford, will discuss the latest EDM techniques and technologies that are continually expanding the horizons of micromachining.

Stop by and say “Hi.” We look forward to meeting with you and helping you hone your EDM skills and technologies.

Since small hole drilling is becoming more popular for production applications in aerospace, medical, electronics, and other sectors that require very small, extremely accurate holes with good surface finish, Makino is seeing a growing demand for machines that can produce these holes consistently and repeatably. Here are some test results that were produced by the Makino EDM Applications Department in Auburn Hills, MI. 

The Applications Department performed this test to prove the repeatable accuracy of the EDGE2 Fine Hole machine. A series of 15 holes, 0.010" (0.254mm) diameter, was made on the machine using 0.008" (0.203mm) diameter copper pipe to predrill each hole, then a solid copper rod was used for finishing. The holes were measured for entrance and exit size, and also shape accuracy on an OGP Quest Vision System. 

There are several factors that determine the accuracy and speed at which the 0.010" (0.254mm) diameter holes can be produced. When the 0.008" (0.203mm) diameter copper tube is at full length, the machining time is longer and a greater taper is produced from entrance to exit for the solid finishing rod to remove. This is indicated by the values shown for holes 1 through 9. As the roughing pipe electrode becomes shorter, the machining speed and break-through at the bottom of the holes are much faster. The roughing process produced a slight taper of 2 ~ 4 tenths (5-11 micron) which was removed during the finishing process. It was critical to perform these tests in a climate controlled room, and to use only the highest quality copper tubes available to reach these results and times. To maintain the better results shown in holes 10 through 15, the electrodes should be purchased in a maximum of 6.0” lengths. All 15 holes where roughed and finished in approximately 60 minutes for an average of 4 minutes to include dressing between holes.

       Hole #       Entrance        Exit               Difference
        1               0.010032”       0.010432”       0.000400”
        2               0.010090”       0.010242”       0.000152”
        3               0.009993”       0.010127”       0.000134”
        4               0.010033”       0.010131”       0.000098”
        5               0.010048”       0.010145”       0.000097”
        6               0.010040”       0.010320”       0.000280”
        7               0.010065”       0.010569”       0.000504”
        8               0.010025”       0.010348”       0.000323”
        9               0.009994”       0.010336”       0.000342”
        10              0.009962”       0.010039”       0.000077”
        11              0.009966”       0.009984”       0.000018”
        12              0.009956”       0.010038”       0.000082”
        13              0.010052”       0.010064”       0.000012”
        14              0.010056”       0.010066”       0.000010”
        15              0.009996”       0.010004”       0.000008”

Cpk Results of Entrances
Based on specific pre-defined requirements for these holes, Cpk is 1.82. 
This Cpk is considered exceptional based on the following scale:
        0 to less than 1.0 is unacceptable - sometimes called "not capable"
        Greater than 1 to 1.33 is fair
        Greater than 1.33 to 1.66 is acceptable
        Greater than 1.66 is exceptional
These Cpk values and ratings are per QualityAdvisor.com

Hole Shape and Location

The holes shown above were photographed at 166x magnification on the OGP Quest Vision System.  Pitch between center of holes was programmed at 0.0250” (0.635mm)

      

The two photos shown above were taken at 403 magnification.  Back light shown at left, surface and back light shown at right.

For more information on these test results or the Makino Edge2 Fine Hole EDM machine, send an email to bill.paul@makino.com.

I have written here in the past about EDM fine hole drilling, but I have some update info that is very interesting.  Makino recently did some testing for a customer who needed a 0.007-0.008" (0.177mm - 0.203mm) diameter hole drilled through 0.75" (19.05mm) of CPM material.  That's a Length-to-Diameter ratio (L:D) of 125:1.  Some will say "That's impossible, it can't be done.".  However, Makino Application Engineers were able to produce this very thing on the Edge2 Fine Hole machine.  Using a 0.006" (0.15mm) diameter copper pipe and a tooling set-up that allows 90 degree incremental part indexing, they were able to produce a 0.0075" (0.1905mm) diameter hole through 0.75" (19.05mm) of CPM-M4.  Here's a picture of the block of material with a piece of 0.004" (0.101mm) wire running through it, and magnified view of the hole itself.  The hole, drilled from both sides to meet in the middle, took 30 minutes.  When the part was cut open with WEDM to inspect the middle of the part where the 2 holes met, there was no visible line or mismatch at the meeting point.

I have provided a lot of information on the use of EDM in aerospace manufacturing through this blog, trade events, webinars on Makino.com, and a recently published article in Makino's aerospace focused magazine, Radical Departures.  These have produced a fair amount of interest from several aerospace primes and top tier suppliers, as well as MROs in the aerospace sector.  I've completed the testing program to gather data for general, non-specific applications, and have sent out over 2 dozen copies of the complete test results to the companies that have asked for them. 

If you have an interest in looking at EDM as a viable process in parts manufacturing for the aerospace industry, from engine parts to landing gear components, contact me to discuss how Makino can help.  We are ready and willing to provide test cuts on specific materials and geometries that your company can perform metallurgical tests on to verify recast and HAZ thickness, existence of micro cracks, surface hardness, tensile strength, etc.  If you would like a copy of Radical Departures, let me know and I will make sure you receive on.  The test cuts and magazine are free.

There's always a good feeling you get after reading an e-mail like this...

"It is a pleasure to write this e-mail. I wanted to express my gratitude for the support I've always received from all of my contacts with the people from SST Group. Mr. Dan Dotson keeps in frequent contact with me on any consumable items that I may need. He always finds time to call me at least weekly to provide updates on SST product updates or to offer encouragement as we navigate this difficult business cycle environment. Many thanks.

I would also like to tell you about the valuable support I receive from another of your highly qualified people. Kevin Most has probably been the biggest reason I have been successful with the investments I've made with Makino EDM's. Many, many numerous times I have clicked on his speed-dial on my cell phone over the last 2 to 3 yrs and have never not been able get in immediate contact with Kevin. I'm not talking about problems with my machines but rather application issues such as helping me by discussing the best way to burn select materials so I can quote a job, or complete a job or just enlighten me as to the capabilities of the SP43. I have one small customer that asks me to burn a shape in carbide that is actually a spline curve which often trips me up on the programming side and Kevin always finds a solution for me. Did you know that he helped me through one of these projects by exchanging e-mails while he was in Singapore last year? Yep, he found time between meetings, tours and training to get the info to me. Unbelievable. Ask him sometime how he worked me through a 4axis application for an exhaust nozzle on a jet engine that turned into a blanket order that lasted over a year and may repeat again this year.

Lately, I've been moving jobs from other wire edm's over to the Makinos to take advantage of using my 'HEAT' settings on quite thin but very rigid work pieces. I don't think 'Heat' is generally recommended for 1/4" or 3/8" thick work pieces however when the parts are in a rigid set-up and very poor flushing 'Heat' works very well.

I will not extend this email further with any more examples of how I've been supported. So let me conclude with this. Picture me in my shop, standing in front of the control on a SP43, cell phone up against my ear, saying "Kevin, how do I get it (the SP43) to do this" That says it all.

When I purchased my second Makino, I told Nick that I made my decision based on buying not just a good machine but also buying the Makino Team. I'm sure I'll feel the same when I'm ready for my third."

Sincerely,
Jack Lanphier Pres.
Lanko Industries, Inc.
Mentor, Ohio

Thanks for the e-mail Jack. It's a pleasure for all of us at Makino to serve our customers.

Makino has recently done testing for a customer in the medical industry for EDM Fine Hole machining.  Part of this testing compared Fine Hole EDM to Laser and conventional mechanical drilling techniques.  The results of the tests were pretty amazing.  The photo micrographs below show the results of all three processes.  As the demand for smaller holes in medical devices, telecommunications and fiber optics, and aerospace applications increases, Makino continues to develop and refine our Fine Hole EDM machines to meet these demands.  Requirements for many of these projects include accuracy of size and shape, consistency in dimensions and locations of entry and exit, and straightness through high L/D ratios.  Check out these pictures and decide for yourself which process produces a better result in tight tolerance, high accuracy hole drilling.  These photos were machined into 316 Stainless Steel, 0.250mm thick, and captured on a scanning electron microscope.  Magnification levels are indicated on the photos.

This 0.015mm hole was developed using using a PICO second laser. Notice the deformation of the entrance hole and splattering of the exit hole.

The following 0.090mm hole was produced using conventional drilling. Notice the differing entrance and exit hole diameters and inaccurate roundness.



The next 0.020mm hole was produced using Makino Fine Hole EDMing. Entrance and exit holes were of the same quality with little to no deformation occurring to either one.




Makino fine hole EDMing was used to produce this 0.100mm hole as well. Once again the entrance and exit holes were virtually of the same quality. As you can see, little to no deformation resulted.