Pearl Way Tools was founded in , by President Mr. Johnny Huang. We has dedicated in developing new products since the company was founded. Until now, we have had more than 20 patented products in the world. Our patent designs improve the inconvenient usage of the conventional tools. During the period from to , for accommodating the demands of the market, we established Chi Te Lung Co.
Neway cutters feature adjustable carbide blades. While the angle is fixed in the tool, the blades adjust inward and outward so that each cutter has its own respective operating range.
The operating range is not the same as the blade adjustment range. Blade adjustment range tells us how far out and how far in the blades can reach for a given cutter, but there is more to finding the right cutter size than simply looking at the reach of the blades more below.
SIZE Use the valve size the valve head diameter to help you find the best cutter diameter. The cutter body diameter the yellow part should be about the same size as the valve. To do a proper valve job you will need three angles : the contact surface and two "narrowing angles" immediately above and below the contact surface. Almost all valves are 45 degrees.
PILOTS Make sure to get pilots that are compatible with the cutters you have selected small series pilots for use with small series cutters, etc. Click here for more on pilot selection. A proper Neway kit should have cutters, pilots, case, wrench, and accessories. Whether you're looking for cutters to do just one valve seat, or putting together a set of cutters to do a range of engines, the process is basically the same: use the valve size s to figure out the appropriate cutter diameter s , and then look for the correct angles.
So how do we use the valve size to find the right sized cutter? It will generate a short list of cutters whose operating ranges include the valve size you enter. We start with the cutter body diameter, this is our reference point with one exception, the Fixed Blade Mini Cutters. Cutter body diameter is not relevant for this special little group of cutters.
This is a general rule of thumb, but it's relatively accurate. The inner operating range is a bit trickier to determine. The actual inward adjustment diameter of the blades is only meaningful when we know the cutter body will be able to fit on to the valve seat, so the amount of clearance around the valve seat area tends to be a more important factor than the actual reach of the blades.
In most cases there will be some surface of the cylinder head - typically a combustion chamber wall or a cylinder head deck - that will limit the cutter size. After all, it doesn't matter how far inward the blades can extend if it's not possible to fit the cutter onto the valve seat.
If your particular cylinder head happens to have very generous clearance around the valve seats then you should take that into consideration. We prefer to use valve size as the reference point because valve size is a term that is clearly understood, whereas valve seat size can mean different things valve seat insert size?
OD of seating surface? ID of seating surface? When the cutter body is bigger than the valve, the chance of success decreases as the size difference increases. Here are the odds of success when the valve is smaller than the cutter body:. These probabilities are not absolute in-stone truth, so please don't drag us into court over them. Every cutter we make has its own page on this website and both the operating range and the actual blade adjustment range are listed on those pages.
The cutter's stated operating range has another consideration baked into it. This one has to do with the role of the specific angle in our 3-angle seat contact angle or narrowing angle. The following example illustrates the point. Let's say we have an old air-cooled VW engine and we're going to cut the following three angles; 15 degrees, 45 degrees, 75 degrees.
In the case of the 45 degree seating surface the outer diameter OD of that surface will be slightly less than the valve diameter, so any cutter that is capable of reaching out to the same size as the valve would be fine.
For the 15 degree top narrowing angle the story is different. In this case we will need a cutter that can cut to a diameter that is slightly larger than the valve size, by some amount we use 2mm.
This calculation is wired into the cutter's operating range. That is, if the blades of a 15 degree cutter will actually reach out to 38mm, the operating range for that cutter will state 36mm as the largest valve. In most cases you will find that there are two or three different cutter diameters that could work for a given valve size. You will narrow your choices down when you consider the angles that you need. As you search through our cutters you will see that we offer both single-sided one angle only and double-sided two-angled cutters.
Double-sided cutters offer the convenience of having two angles on one tool while single-angled cutters make it possible for you to purchase just the angle you need without having to pay for a second angle on the opposing side of the cutter cutter pricing is based on the quantity of carbide blades on the cutter.
Since you will need the ability to cut three angles you may wind up with three single-sided cutters, or one double-sided cutter and one single-sided cutter. It really makes no difference either way, the mission here is simply to cover our size range with the three angles we need.
When there are multiple cutters to choose from, other considerations might help us boil it down. For example, we may have the option of choosing between five-bladed cutters and three-bladed cutters. Five-bladed cutters cost more than three-bladed, as cutter pricing is based on the number of carbide blades on the cutter.
For valve seat work requiring hefty stock removal, such as valve seat oversizing, five blades is definitely the way to go. In terms of accuracy, there is no difference between the two. Neway offers three different series of valve seat cutters and pilots: standard series, small series, and heavy duty series. Standard series cutters work with standard series.
Heavy duty series cutters and pilots. Remember, we prefer to use the valve head diameter as the reference point when we describe the operating range of our seat cutters. Your decision will be influenced first and foremost by the type of engine you are servicing. If you're working on power equipment engines Briggs, Honda, Kohler, etc.
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