TAVARES, Fla., Feb. 4, 2020 /PRNewswire/ -- GWS Tool Group is pleased to announce it has acquired North American Tool Corporation (NATC). 

"NATC is an exciting add for us," said Rick McIntyre, GWS' CEO. "Their customer service model is one of the best in the business, and their focus in taps and threadmills fits in like a perfect puzzle piece to our dynamic and holistic offering. We are very excited to be continually expanding our value proposition for our customers with highly additive acquisitions like this," McIntyre continued

"North American Tool is very excited to be joining GWS Tool Group, a company that embodies the attributes that have long made us successful," said Curt Lansbery, NATC President & CEO. "A customer-centric approach to business rooted in a commitment to quality and quick delivery marry perfectly with our model here at North American Tool. We have no doubt that this move to join GWS will be positive for our associates and will ensure the continued growth of the legacy that we have worked to develop."

The team at NATC will continue to operate from the Illinois facility as a manufacturing arm of GWS Tool Group, and the company expresses intent toward continued investment in the facility, machinery and equipment, and human resources. Customers of NATC are said to expect continuity of the NATC offering and customer service disposition under cover of the GWS ownership.

About GWS Tool Group
GWS Tool Group is a U.S.-based, vertically integrated manufacturer of highly engineered custom, standard, and modified standard cutting tools, primarily servicing the aerospace and defense, power generation, automotive and medical sectors. GWS Tool Group has acquired multiple businesses in the course of its growth, which now serve as the respective manufacturing divisions of the Company.

by Bernard Martin

Retention Knobs are the critical connection between your machine tool and the tool holder and they are the only thing holding a steep taper tool holder in the machine’s spindle.

​Techniks has recently introduced their MegaFORCE retention knobs that have some rather unique features when compared to standard pull studs.  Before delving into the features of the MegaFORCE pull studs, let's review some things that you may not know, or think about, on a daily basis. 

However, if you're running multiple shifts, 24-7, making lots of tool changes, making very heavy cuts with long reach or heavy cutting tools, and/or have ball lock style grippers instead of collet type grippers used on the retention knob, you will probably need to replace your studs at least every six months.

Given the spindle speeds that we are running at to remain competitive, retention knobs are not an item that you want to take a chance on breaking.  I can tell you firsthand that 5 pound toolholder with a drill in it flying out of the spindle at 23,000 RPM is not something you want to experience. 

Pull studs encounter catastrophic failure as a result of metal fatigue. The metal fatigue can be caused by a number of reasons including poor choice of base material, engineering design, machining process, poor heat treatment, and, sometimes, they have just met or exceeded their service life. We're going to dig into each of these reasons below but first let's look at some threading fundamentals.

That is why the length of engagement of the thread on a pull stud is generally limited to approximately one to one & a half nominal diameter. After that, there is no appreciable increase in strength. Once the applied load has exceeded the first thread's capacity, it will fail and subsequently cause the remaining threads to fail in succession.

The most common failure point for a retention knob is at the top of the first thread and the underside of the pull stud where the grippers or ball bearings of the drawbar engage and draw the toolholder into the spindle.

Remember, bigger Radii are stronger than sharp corners. ​More on that soon.

Not all retention knobs are made from the same material, however, material alone does not make for a superior retention knob. Careful attention to design and manufacturing methods must be followed to avoid introducing potential areas of failure.

MegaFORCE retention knobs are made from 8620H. AISI 8620 is a hardenable chromium, molybdenum, nickel low alloy steel often used for carburizing to develop a case-hardened part. This case-hardening will result in good wear characteristics.  8620 has high hardenability, no tempering brittleness, good weldability, little tendency to form a cold crack, good maintainability, and cold strain plasticity.

There are some companies making retention knobs from 9310. The main difference is the lower carbon content in the 9310. 9310 has a tad more Chromium, while 8620 has a tad more nickel.  Ultimate Tensile Strength (UTS) is the force at which a material will break. The UTS of 8620H is 650 Mpa (megapascals: a measure of force). The UTS of 9310H is 820 Mpa. So, 9310H does have a UTS that is 26% greater than 8620H.

​That said, Techniks chose 8620 as their material of choice because of the higher nickel content.  Nickel tends to work harden more readily and age harden over time which brings the core hardness higher as the pull stud gets older. The work hardening property of 8620 makes it ideally suited for cold forming of threads on the MegaFORCE retention knobs.

​It should be noted that some companies are using H13. H13 shares 93% of their average alloy composition in common with 9310. 

Rolled threads produce a radiused root and crest of the thread and exhibit between a 40% and 300% increase in tensile strength over a cut thread. The Techniks MegaFORCE retention knobs feature rolled threads that improve the strength of the knob by 40%.  

In order to maximize the life of your retention knob and prevent catastrophic failure here are some technical tips to keep your shop productive and safe.

Special thanks for Greg Webb at Techniks and Mike Roden from Fette Tools/ Turning Concepts, for providing technical insights. 

Blue Photon manufactures a patented photo-activated adhesive workholding system in the U.S.

​They also offer fixture design and engineering for milling, turning, grinding, electrical discharge machining (EDM), 3D printing/additive manufacturing, laser, inspection and assembly applications for the aerospace, medical, optical, and robotic industries.

You can view or download the catalog below.

​For a more in-depth visual of how Blue Photon’s UV workholding technology is a solution to your workholding needs, check out their videos HERE. ​

In February of last year we posted Horn USA's Construction Cam. If you check it now, you'll see the new USA Headquarters.

In September 2020, all of the company’s production capabilities were relocated to a new facility 0.5 miles from the original office suite. Interestingly, this substantial expansion has been on the company’s radar for many years.

In 2002, a new management team was established. One of the goals the team set during its first few months was to find a permanent location for Horn USA. Large buildings in the light industrial zone are not commonplace in the immediate area of Horn USA, so it took a while to find the ideal opportunity.

Finally, in 2016, 10.76 acres with a 101,000-square-foot light industrial building became available. In typical Horn fashion, advantages and disadvantages were analyzed and finally one came together to the conclusion that this real estate among other things because of its proximity to the existing plant, provided the ideal solution to the next stage of expansion.

In the third quarter of 2019, construction began to bring the facility to the standards expected of Horn. In total, this meant an investment volume in buildings, conversion and technical equipment of approx. 29,000,000 dollar (approx. 25,000,000 euro). Nearly 400 people in all have been involved in the 14-month construction project. The new building has a total area of 11,000 square meters and can accommodate up to 300 people. Horn USA currently employs 120 people.

According to Andreas Vollmer, President Horn USA,

“The new building in the USA makes a clear statement and demonstrates our commitment to the American market. Other than our home market of Germany, this is our strongest international market and has been for a long time. It is also one that holds huge potential for our solutions in the future. The new building provides us with the space we are going to need for this. We are very proud of taking this step and are convinced that it will ultimately benefit our customers as well — in the form of increased production capacity, larger training rooms and our new demonstration centre, for example.”

​New optical workholding adhesives provide alternate solutions
to the challenges of traditional holding methods
written by Dan Billings & Shannon Osborn, Blue Photon 

New processes 

With new adhesives, traditional holding processes change. First, a thick layer of adhesive is applied between the part and holding device. Grippers are inserted into a fixture and can serve as the interface between the workpiece and holding device if needed. The workpiece is then secured to the grippers with the workholding adhesive, which is cured with UV light transmitted through the core of the gripper. The average tensile holding power of the gripper is between 200 and 605 lbs per adhesive joint and based on the size of the gripper selected. 

When the workpiece is loaded, UV light is either passed through the grippers or the workpiece material for 60 seconds to cure the workholding adhesive. Once cured, the workpiece is held in place securely, which allows for aggressive processing. The parts can then be removed from the holding device by hot water soak with a temperature between 170 and 200 ºF. The high temperature eliminates the need for toxic solvents and allows for faster release of the adhesive. Typical debonding time generally runs 2 to 5 minutes. Residual adhesive is easily removed by applying pressurized steam or hot water spray in conjunction with a gentle peeling action (Figure 4).

1. BUILT TO LAST
Designed to tap even the hardest materials, HSSE taps are made from high speed steel, which contains a higher concentration of cobalt and vanadium. This composition lends incredibly high resistance to wear, resulting in much longer average tool lives. Due to this, you can be confident that you’re purchasing a lasting, durable solution.

2. COLOR CODED
When selecting taps, the number of available options can often be intimidating. To address this, Allen Benjamin color codes all of our products. With six color rings available, you — and your employees — will be able to easily locate the exact tap that they need, when they need it, thus reducing downtime, increasing efficiency, and preserving profits.

3. A TRUSTED SOURCE
When you source from Allen Benjamin, you can rest easy knowing that you’re working with the industry’s most trusted supplier of HSSE and carbide taps. Just like F&L Technical Sales, Allen Benjamin is committed to treating our customers to a better experience, we focus on delivering high-quality products and — more importantly — attentive, knowledgeable customer service.

Our F&L Technical Sales team will work with you to understand your application, recommend potential solutions, and supply you with the taps that you need. So, if you’ve been considering a new supplier for your operation’s carbide taps, HSSE taps, or smart tapping fluid, be sure to browse our website and contact us with any questions you have.

ORIGINAL GMN PARTS
GMN USA utilizes only the best components when refurbishing spindles. The use of GMN ABEC 7 and higher quality bearings assure the best possible accuracy and reliability for their spindle repairs. Motors, clamping systems, sensors and other critical parts supplied by vendors must meet strict GMN quality standards. All this attention to detail ensures that spindles are returned to our customers with “like new” performance and reliability. 

BEST EQUIPMENT
GMN USA is equipped with a variety of grinding machines that cover all of their grinding requirements. All spindle component grinding operations are completed in their facility to ensure high quality and a quick turnaround time. The GMN USA assembly and test departments utilize state of the art spindle drives and vibration analysis equipment to confirm that each spindle meets very exacting demands.

QUALIFIED TECHNICIANS
The experienced team of engineers, machinists and spindle technicians at GMN USA is focused on providing the best possible service and technical advice to our customers.

Their spindle repair service includes an accurate evaluation of incoming spindles, replacement or refurbishment of damaged components, dynamic balancing, extensive testing and vibration analysis. 

Below is a video showing GMN USA in Farmington, Connecticut going through their spindle repair process. It is the most comprensive repair process in the industry.

If you're thinking about getting a new spindle from high speed grinding to high power milling applications, GMN has the solution for all your machining needs.

In addition to a comprehensive range of standard spindle types, GMN also will design and develop special spindles to meet the specific requirements of our customers.

GMN is a market leader for spindle technology worldwide, especially in the field of innovative solutions for precision and high speed machining.

Give us a call with questions! 

by, Bernard Martin

As carbide end mills gain higher and higher speeds and metal removal rates there has also been a trend by round tool manufacturers to tighten up the tolerances on both the cutting diameter and the shank diameter to improve concentricity. At the same time, shrink fit holders have become more and more popular because they hold a tighter concentricity as well.  To achieve this both the shank and the bore now have similar surface finishes and this has led to a problem  The tools pull out in the cut.

Shrink fit holders are the most accurate for TIR as the toolholder engages completely around round shank tools with a bore tolerance of -0.0001" to  -0.0003".  As high performance end mills have tightened shank tolerances to the same range of -0.0001" to  -0.0003" they have used finer and finer grain grinding wheels which give the shanks a 'shiny' appearance. 

Shiny means that the superfinished shank has a lower coefficient of friction. So, although the TIR is tighter, the shank is more "slippery".   End mills traditionally had surface finish of about 8 μin on the tool shank. But that's changed.  It's been recommended that tool shanks used in shrink fit holders should not have a finish finer than 16 μin. for optimum holding power, but tell that to the guy who just superfinished the end mill to a super cocncentric tolerance that you don't want it looking that good.

Everyone know that the last thing you want is for the end mill to slip in the middle of a heavy cut or on the finishing pass of a high tolerance part.  These 'hi performance' end mills, often times have higher helix angles which are great for ejecting chips but also create a higher pull out force on that slippery shank. And reducing the helix angle is not the answer.

We  already know that the gripping pressure is a function of the interference between the tool shank  and the shrink fit toolholder bore. Most shrink fit holders have a already bore surface finish of between 12 μin. and 16 μin.  So they are ground to a very high tolerance and have about the same surface finish as the toolholder shank.

End mill manufacturers and machinist have tried a variety of methods over the years to stop the tools from pulling out. This has ranged from grit blasting the shank to rubbing chalk on the shank, but most everyone in the industry has felt that the problem really needs to be addressed by the longer life toolholder rather than the replaceable cutting tool.

The Challenge 
The challenge was to achieve both hard and soft cost savings, as well as time spent on drilling flanges from one side, chamfering the backside and creating a controlled chamfer on the top surface which was a secondary process.

The Solution
We designed an indexable drill with our rear cutting carbide deburring insert along with a fixed pocket chamfer insert to create the precision top chamfer that was required. The spade drill insert also had a special feature that allowed it to chamfer the top side of the bottom hole that was pre-drilled.

The Results
​Four operations were completed in one pass.

The EZ Burr Burr-Free Drill drilled the hole, deburred and chamfered the back all in one step, thus eliminating the secondary step of chamfering the bottom surface on the top hole.

This saved time as well as money, plus the tool life of the Burr-Free Drill achieved a more consistent result and had a longer tool life than the previous method.

This article is about Blue Photon Technology and Workholding Systems LLC  and how Post Processing; 3D printing presents challenges in workholding for finish machining.
Written by Mark Kirby AM Business Manager, Renishaw Canada

Metal 3D printing can enable rapid, low cost iterations of new medical devices, since no tooling costs are involved. All devices need testing to uncover problems and develop solutions—allowing the product shape to change “for free” is a powerful advantage with Additive Manufacturing (AM). Other benefits flowing from AM besides enabling more complex geometry are improved accuracy with no component tolerance stack up, and a simplified supply chain with reduced part count.

Plastic printed jaws are often a good first option, as they are cheap to manufacture—typically in just a few hours on a desktop printer, and can conform to complex geometries (although the design of the jaws can be more time consuming than a simple Boolean subtraction of the component from the plastic). When the design changes after product testing it is easy to print a new set of jaws.
​
The main disadvantage of plastic jaws is that they will often distort the component as they are tightened. Although the jaws hold the part rigidly for machining, when the component is released from the fixture any machined bores may no longer be perfectly round, and true positions of features will have moved slightly as the component relaxes back into its unloaded shape.

The tracker body was monolithically printed in titanium alloy  Ti6-4, stress relieved and then cut from the build plate ready for finish machining of the kinematic mount and the four posts that hold the optical reflector globes.
​
A plastic set of jaws was designed to clamp the part while leaving the machining areas exposed. Although the plastic jaws clamp the part rigidly, they never clamp the part repeatably, so the exact position of the part must be found using a machine probe and best fitting software such as NC-PerfectPart, from Metrology Software Products Ltd. (MSP). Originally developed for machining of high value aerospace and Formula 1 composite structures, this software is perfectly suited to the challenge of precisely locating an organic-shaped AM part with no obvious datum features.

Points are selected on the component in the CAD environment and the deviations from nominal positions are measured by the probe on the CNC machine. The NC-PerfectPart software then creates a best fit alignment that is a 6-axis coordinate transformation—both translation and rotation. This coordinate shift is automatically recalled into the machine controller before CNC programs are executed.

Unfortunately, the hip tracker component flexed imperceptibly when the plastic jaws were clamped, resulting in true position errors greater than 0.3mm on the machined posts. While the component had been optimized for handling loads during surgery, it had not been designed to resist machining forces.
In order to machine the part accurately it was essential not to bend it with mechanical clamping, but at the same time it was equally important to add rigidity.

The solution was to use Blue Photon’s UV activated adhesive and grippers. By gluing the part onto four gripper posts (that transmit UV light to cure the glue in approximately 90 seconds) the hip tracker was held firmly but still in the free state.

An aluminum block was machined to hold the four gripper posts in the correct positions for the tracker body. Initial machining was successful on the three posts directly bonded to the grippers, but one post was cantilevered above the gripper and vibrated during machining. A plastic support block was printed to hold this post and eliminated this problem. By cradling the part, the support block also allowed for more accurate positioning of the tracker prior to the glue being cured. The glue thickness is optimally around 1mm, and after machining the part and fixture can be separated by simply immersing the assembly in near boiling water for a few minutes, and then peeling apart.

The only disadvantage of using the glue grippers appeared to be the extra work to design and machine the gripper fixture. However, on a subsequent project for an industrial impeller Renishaw used plastic printing to produce the gripper fixture instead of machining. This proved that the manufacture of a robust, custom workholding solution can be reduced to an overnight desktop print.

The procedure for a patient specific medical device like a cranial plate would be as follows. The number and placement of the grippers would be determined by the manufacturing engineer. “Preserve” regions would then be defined around each gripper as a cylindrical “bushing” with obstacle clearance regions extruded axially above and below each gripper to allow for insertion and captive nut placement.

​The cranial plate is also defined as an obstacle that must be avoided. A preserve ring would be defined, and constrained, to enable the completed fixture to be held in a chuck. Loads are added to the gripper bushing preserve regions to represent machining forces that must be resisted. The software can then solve the structural connection of all the parts for maximum stiffness.

One of the barriers to adoption of patient specific solutions is the high design cost typically involved. Using generative design coupled with plastic printing is an innovative solution that largely automates the workholding process with Blue Photon’s adhesive grippers.