Tooling Advances Drive New Product Designs

The Vollmer erosion machining center measures the dimensions for teeth of a PCD blade.

Major manufacturers are eagerly adopting designs and production techniques that reduce the weight of their finished goods, in order to increase operating efficiencies. Aircraft builders have replaced stainless steel with carbon fiber-reinforced plastics (CFRP) materials to reduce the weight of their jets and planes. It’s a switch that is improving fuel mileage and the crafts’ durability because this product is much lighter and stronger than stainless.

A more obviously, example perhaps is automotive OEMs, who are aggressively seeking ways to reduce the weight of their products, in order to achieve better fuel mileage. For car and light truck engines, as well as for heavy equipment designs, the shift from gray or ductile iron to compacted graphite iron (CGI) is accelerating. It not only decreases the weight of the components but improves the structural integrity, too.

Replacing traditional materials with newer composites and alloys accomplishes various design and performance goals, but the new materials create additional machining challenges due to their hardness and the abrasiveness of the individual materials.

For example, silicon-aluminum engine blocks and transmission housings have enabled the producers to reduce the weight of these components up to 40% by comparison to their predecessor components. The inclusion of silicon metal in aluminum castings reduces tool life for existing carbide cutting tools and carbide-tipped saw blades. The price will be seen in the labor costs and production time lost to tool changes: some carbide tools may need to be changed 30 times for each tool, and some changes may take 1-2 hours to complete.

Replacing carbide blades
Polycrystalline diamond (PCD) tools and saw blades have successfully replaced some of these carbide cutting materials, increasing tool life, improving finishes and decreasing unit costs for the producers. RKO Saw and Tool manufactures and supplies carbide and PCD saw blades, and has had considerable success at converting its customers’ operations from carbide to diamond tooling and saw blades. One particular customer, a producer of cast aluminum engine manifolds, realized a 30X improvement when converting from carbide to PCD saw blades.

A saw blade is loaded into a Vollmer erosion machine prior to finishing.

Three brothers established RKO Saw in the early 1970s, about the same time that polycrystalline diamond was developed and introduced to the metal industry. The second generation of owners, Ron and Carey Wiesner, took over in the 1990s, and the past 20 years or so have been paced by significant growth in the business.

The Wiesners attribute much of the growth to ongoing investments in new equipment and technology. For example, they have installed six robotic work cells to the operation, each one capable of unattended grinding to produce up to 150 saws. “This gives us a dramatic increase in capacity and reduction in labor cost,” according to the Carey Wiesner.

Automation was introduced to to eliminate costs and reduce variability in blade processing. Carey states that purchasing the first piece of robotic equipment was the hardest decision he had ever made, but the next five choices were much easier. “The quality and consistency pays for the equipment over and over,” he now realizes. The Wiesners’ strategy of continuous improvement has helped RKO to become a leader in the supply of PCD tools and saw blades today.

The present operation in Cullom, Ill., covers 16,000 ft², with 22 employees producing and servicing 40,000 carbide and PCD saw blades per year, in addition to PCD tools. Although the average blade size contains 60 to 80 tips, RKO has produced PCD blades up to 36 inches in diameter for specialized applications.

The emphasis on growing the PCD blades portions of the business has been grounded in applications relating to aluminum casting. However, applications continue to evolve in industries as diverse as window manufacturing, printed circuit boards production, and construction of composite components for naval and aerospace equipment.

Successful conversions
RKO has been very successful at using its knowledge of PCD materials and tool designs to assist its customers to improve their plants’ productivity. Four years ago, RKO successfully converted an engine manifold manufacturer from carbide-tipped saws (300 mm, 80 teeth, 4 mm kerf), to PCD tipped saws (300 mm, 40 teeth, 5 mm kerf). The manifold manufacturer uses the saw blades to remove risers and over pour on the finished aluminum castings.

Because of the high-wear rate of diamond cutting tools when cutting PCD blades, erosion machining is the most cost-effective finishing process for the blades.

“We approached the manifold manufacturer because of the success we had with a piston manufacturer,” Carey explains. “The materials are similar and we felt PCD was suited to their operation.

“The end user was extremely hesitant about the change because of the initial cost,” he continues. “We had to give them free samples just to get them to test. At that point the tools sold themselves and the engineer took full credit for the savings.”

Using the carbide saws, the customer was averaging 1,000 parts per turn: once PCD blades were adopted, that average increased to 30,000 parts per turns, and now after further optimization of PCD grade and geometries they currently average 38,000 turns per blade. The 38X improvement in production also cut downtime associated with blade changes by a significant amount.

“The PCD blade does have a higher per unit cost of $950 when compared to the $145 carbide-tipped blade,” Carey Wiesner allows. “However, the cost per part is reduced from $0.145 with carbide, to $0.025 with the PCD blades.”

Due to the abrasive nature of the diamond or PCD portion of the tool, specialized equipment is required to shape or machine the diamond cutting edge. Traditional grinding can be used in the fabrication of certain diamond tools; however, the diamond grinding wheel wears quickly when tasked with grinding the PCD. As a result of this excess wear, erosion machines are the most cost-effective choice today.

Vollmer is the technology leader in this machine tool niche, with several types of equipment that use various rotary and wire erosion methods. “They can manufacture or sharpen just about any PCD tool that exists,” according to Ron Wiesner. “We are constantly looking for new industries where we can introduce PCD tooling, and the Vollmer equipment is so versatile that there is no limit to the markets we can enter.”

The erosion process takes advantage of the conductivity of the PCD layer to “arc” or erode the diamond, in order to obtain the desired geometry for the finished tool. In 2008, RKO invested over $1 million in new capital equipment including erosion machines. “We first purchased a Vollmer QM ECO which can sharpen profile as well as straight tools,” Wiesner now recalls. “Six months later we purchased Vollmer’s QR and QF models, with robotic loading capability. This cell gives us the ability to erode the outside diameter and the side geometry of PCD saws with one set-up.”

New applications for PCD
The Wiesners credit these investments and the PCD industry with sustaining them during the recent economic downturn.

As the manufacturers continue to develop new grades of PCD, additional applications are identified. These new applications call for finer grades of PCD that will be used with various grades of titanium; veined PCD drills and end mills that create major advantages in the aerospace and automotive industries; and some of the multi-modal grades destined for various solid surface applications in erosion. Knowledge and awareness of these materials continues to spread through the various industries where the applications lie, so the potential end-users worldwide continue to learn about their opportunities to become more competitive — thanks to PCD cutting.

Diamond has always been the hardest substance on earth, as most people realize. Their awareness of its excellent application as a cutting tool material continues to grow. And, the applications for PCD continue to emerge as production demands evolve and tighter tolerances are requested in all industries.

Demand for lighter and stronger products promotes the development of new materials that are more and more difficult to machine. Global competition increases the need for production efficiencies. And, opportunities for PCD tooling continue to grow, as forward thinking companies like RKO Saw lead the advance.

source by http://www.americanmachinist.com/

How to cutting Cutting Plywood with saw blades

Here is How to cutting plywood with saw blades, When cross-cutting a plywood panel, the bottom layer of veneer often splinters out along the cut line. But there are steps you can take to prevent this.

Perhaps the easiest way to avoid splintering is to use a blade that's made just for cutting plywood. These blades have lots of teeth (typically 80), and the teeth are ground in a pattern that creates a clean, shearing cut.

But what if you don't want to spend the money for a single purpose, rarely used saw blade? There are a few tricks you can use to get a clean cut with a combination blade.

First, if the blade is crusted with sawdust or pitch, clean it before cutting the plywood. Sometimes, however, even a clean blade will splinter the veneer. There are two reasons for this. One is that a combination blade has fewer teeth than a plywood-cutting blade, so it doesn't cut as cleanly.

The other reason is that the cutting edge of the teeth may be pushing the veneer down rather than slicing it off.

One way to avoid this is to change the cutting angle of the teeth by raising or lowering the blade. If your panel is splintering on the bottom, lower the blade. If it's splintering on the top, raise the blade.

The most common way to get a clean cut is to score the panel along the cut line before making the cut. To do this, cut through the veneer layer with a sharp utility knife.

While this method works, it's sometimes difficult to line up the saw blade with the scored line. An easier way is to score the panel is to use the saw blade itself. The idea is to make the cut in two passes. On the first pass, set the blade just high enough to cut through the veneer layer. Then raise the blade to finish the cut on the second pass.

Another way to keep the veneer from splintering on the bottom is to use a backer board. This is a piece of plywood or Masonite that's placed below the workpiece when making the cut. This way the veneer layer is fully supported and the plywood can be cleanly cut.

The Different Varieties of Scroll Saw Blades Used for Intricate Cuts

A scroll saw is used to generally cut intricate cuts. To help the scroll saw perform these types of cuts you will find the need to have a variety of scroll saw blades. These blades which are available from hardware stores are designed for many different purposes. For this reason you should either have a large variety of scroll saw blades or depending on your crafting abilities a few specialized blades.
There are about six different major varieties of scroll saw blades that are available. These blades are generally about five inches long. A brief look at the different scroll saw blades will let you see how these blades are different in nature. The first one we will look at is that of the Skip tooth blade. The skip tooth blade is named due to the saw teeth being positioned with a gap distance between each tooth.
The next type of scroll saw blade to be looked at is the Crown or two way saw teeth. In this blade type the teeth of the blade are facing both upwards and downwards. This double direction facing teeth on these scroll saw blades allows you to make cuts in the material. You will have the option of cutting in a downward stroke. You could also cut using an upward stroke. This is very handy as there may be times you will need to cut the wood in either direction. Another of the scroll saw blades is that of the Double Skip tooth. In this the teeth of the blade is fashioned in a manner that is similar to that of Skip Tooth blade. You will find however that the gap is located after two saw teeth have been found. In other words the arrangement of the teeth for this blade is two teeth, a gap and then another set of two teeth. You can use the Metal cutting scroll saw blades for the purpose any cutting any type of metal. Here the blade is made from hardened metal. Now if you are cutting any other substance such as glass with a scroll saw it is best if you use a Diamond blade.
This particular blade has a diamond coated wire blade. This is truly the blade to use when you need to cut through glass. The final major scroll saw blade that we shall look at is that of the Spiral blade. This blade is formed in an unusual way. This blade is a flat blade that has been twisted so that the teeth of the blade are facing in every direction. This makes using this type of blade perfect for the tasks where you need cutting ability in just about any direction. You will find all of these saw blade useful. While these are a brief look at the major scroll saw blades you will find that there are many other blades to use. See what the various saw blades are like. You might find a few more useful ones.

Sawblades with Different Machines and Applications

This Table to explained about kind of sawblades with different machines and applications. maybe you can select the best for you project.

Kinds of Blades	Machines	Applications
Aluminator	Compound Miter Saw	Aluminum & extrusions 3/16 "- 1/2"
Compound Miter Saws	Contractor	Aluminum & extrusions 1/2" - 1"
Contractor	Double Miter	Aluminum & extrusions over 1 1/2"
Dado Chippers for Fine Dados	Gang Rip	Average Ripping
Dado chippers for Superfine Dado Set	Jump Saw	Combination - Rip & Cross
Dado Saws (Outside L&R)	Miter Saw	Combination - Mostly Rip
Double Miter	Panel - Horizontal	Combination - Mostly crosscut
Fine Dado Set	Panel - Vertical	Copper, Brass to 3/8"
Gang & stright Line rip	Portable Table Saw	Copper, Brass over 3/8"
General Purpose	Radial Arm Saw	Copper, Brass over 1 1/2"
Glue Joint Rip	Rip - Glue Joint Rip	Crosscut to 1"
Heavy duty metal	Rip - Heavy Duty	Crosscut to 2 1/2"
Heavy Duty Rip	Rip - Safety Rip	Crosscut over 2 1/2"
Horizontal Panel	Sliding Table Saw	Double Laminate
Jump Saw	Special machines	Double Miiter
Laminate - Veneer	Straight Line rip	Laminate on particleboard to 1"
Melamine Veneer	Table Saw	Laminate on particleboard to 2 1/2"
Miter Box	Vertical Panel	Laminate on particleboard over 2 1/2"
Plastic & trim		Miter / non-ferrous
Plymaster		Miter / Plastic
Precision support collars		Miter / Wood
Precision trim		Non-ferrous metals
Radial Arm Saw		Particleboard
Rescue		Plastics general
Rip - Glue Joint Rip		Plastics hard / brittle
Rip - Heavy Duty		Plastics medium
Rip - Safety Rip		Plastics medium / soft
Safety Rrip		Plywood
Saw Bushings		Plywood veneer
Scoring Blades - 2 piece split		Ripping - Rough
Scoring Blades Conical Grind		Ripping - Smooth
Sliding Table Saw Blades		Ripping green Lumber
Solid Surface		Wood
Stainless Steel Dado Shim Sets
Super finish Trim Saw
SuperFine Dado Sets
TFE Bandit - Coated blades
Thin Line
Vertical Panel Blades

How To Use Saw Blades Correctly

follow the below rules in order to reach the best cutting results:

• Machine must be in good condition without vibrations
• Flanges used to tighten the saw blades must be of the same diameter (about1/3 of the blade size)
• Flanges must be clean and it is important to check their side run – out
• Check the spindle of machine. It must be absolutely straight (picture 1)

(picture 1 Check the spindle of machine)

• Tips must always be sharpened with the original angles
• See the most appropriate way on picture 2

(Picture 2 Tips must always be sharp)

• If rebored by over 20mm, the blade loses its original attributes and its stability (picture 3)

(picture 3 bore of saw)

• It is needed to grind the top of chip limiters together with tip grinding and keep the oversize as picture 4

(picture 4 op of chip limit)

Setting Height of Saw Blade

Setting height of the saw blade on the machine is very important to produce a good piece of Aluminum, while the distance of the height setting is a good chainsaw :
1. Tipped of Saw blade out of the object in a piece is 3 to 6 mm
2. Setting the saw blade must be done on both spindle machine (Right spindle and Left spindle)

Note : A = 3 mm ~ 6 mm
B = Thickness of Aluminum
C = A + B

Maintenance of Saw Blades

1. For longer life with your saw blade, your saw and equipment must be in proper condition. Whenever you install a new blade, check your arbor shaft for radial and axial play. Try moving the shaft back and forth, and in and out. Any movement indicates the arbor shaft needs adjustment, new bearings, or replacement.
Lapidary blades are manufactured with the arbor hole .005" oversize to provide a snug fit on the shaft. If the shaft is worn, the blade will not spin concentrically with the arbor.
The machine should be located on a level floor or platform so that it will not vibrate during operation. All belts should be properly tensioned.

2. Flanges support the blade over a large surface area and help prevent deflection at the beginning and ending of a cut where there is little or no workpiece support. They must measure at least one quarter of the blade diameter. Make certain the flanges are smooth, flat and parallel, without gouges or burns on the surfaces. Flanges must be recessed about three quarters of their diameter from their center. This provides support to the blade around its outer area while avoiding distortion of its center core.

3. A lapidary diamond saw blade requires a lubricant which also works as a coolant. An ample supply must be directed into the saw cut to lubricate the blade rim and workpiece, and to flush out all debris. A light cutting oil is best, and is required for most slabbing operations. A water soluble oil or plain water can sometimes be used in trimming operations. Rust inhibitors should be used and extra care taken to prevent rusting of the blade and/or saw.

4. With a new blade it is best to make your first cut using a soft, abrasive material. This will assure that the blade is properly broken in by bringing the rim into concentricity with the arbor and will open up the rim, increasing diamond protrusion.

5. Start cuts by feeding in the workpiece when the blade is running at operating speed. Make sure the surface of the workpiece will not cause the blade to deflect at point of contact. If the blade starts cutting to either side of its plane of rotation, you will get a nonparallel cut and even damage to the blade.
When a cut is almost complete, a break will often occur, leaving a jagged spur. This spur can damage the blade. To prevent this, in feed pressure should be reduced or stopped near the end of the cut. Saws with automatic power cut-off, when properly set, will do this for you. With screw feeds, the workpiece and vise can be hand fed.

6. A diamond blade should be reversed occasionally to insure even wear and long life. A diamond blade can become glazed over at its cutting edge especially when cutting hard, dense material. To sharpen the blade, make a few cuts in a soft, abrasive material. This will generally abrade away some of the metal bond and rim and expose more diamond.

source : www.diamondpacific.com

Accuracy in Spindle of Machine Saw Blades

Here are easy recommendations to know Here are three easy recommendations to help choose the right tool for high performance in machining operations.
(1) Shaft
Run out (A) within 0.02 mm move to direction of shaft (B) within 0.03
(2) Flange
There are not scratch, burr, dirt run out of outside (C) within 0.02 mm

Picture of Accuracy in spindle machine operation

Follow these easy steps, and you should be well on your way.

Thank you to read for providing these machining tips.