Are you tired of cutting corrugated high-speed steel knife blanks for moulding knives that get severely burnt on the edges during the cut? Sometimes the burning can be so severe it takes the temper out of the profile area on the knife blank. Over the years we have had the ability to use and test many different styles of chop saws and cut off wheels. We want to share some firsthand knowledge of what chop saws and cut off wheels we feel work best for the moulding industry.
First, we recommend a chop saw capable of utilizing either a twelve or fourteen-inch diameter cut off wheel for a one-inch arbor. Keep in mind that a twelve-inch wheel will result in less cuts per wheel, costing you more money over time for replacement blades. Something else you should consider is how much horsepower you will need on the motor. The higher horsepower motors develop cleaner, straighter cuts and generally have a longer service life. A decent chop saw could cost anywhere between $300.00 - $2,000.00. Purchasing decisions will greatly depend on how much knife steel you will cut over time. We have cut thousands of high-speed steel blanks for manufacturing moulding knives over the years. We proudly own a Kalamazoo KM-14” (made in the USA) five horse power, 4400 rpm chop saw, and a Kalamazoo dust collection system (to help keep our lungs clean along with the 3M N95 respirator mask). Most moulding production shops would not justify spending such a lofty amount just to cut high speed steel blanks, but for us, cutting thousands of knife blanks over the years the price is rationalized. For most small moulding companies any of the big box store brand of chop saws such as Makita, Milwaukee, DeWalt, or Porter Cable will work just fine for hundreds if not thousands of cuts.
Let’s briefly discuss which cut off wheel we use for the best overall success in cutting high speed steel blanks for producing moulding knives, over the years we have tested about a dozen different manufacturers abrasive cut off wheels with limited success. After many attempts and years of finding the best cut off wheel for our industry, we have always returned, and currently use the Makita Noritake 14” diameter, by 1/8” thickness, and a one inch bore with a max operating speed of 4400-rpm, (part # 724603). Over the years, Makita has phased out these wheels at 4400 rpm’s and replaced them with a 3900-rpm wheel, (part # B-10849). It is in our opinion, that the change in max rpms of this cut off wheel, is not as good as the # 724603 Noritake that we have become fond of. In more recent years we seen a change in the thickness of some of the wheels made by Makita, from 1/8” to 7/64” (part # A-93859) 3900 rpm. This thickness change causes the wheel to wobble a bit while making cuts, until it loses a little of the wheels diameter from cutting, it’s a little nerve racking and unsafe.
There is a type of cut off wheel we would advise you to avoid. The internally reinforced wheels that have checkerboard fiberglass mesh that you can see in the images we provided, these types of wheels severely burn the edges of the steel, they also chip, and begin to fall apart after twenty or thirty cuts. This excessive burning not only looks bad, it is decreasing the milling life of your knife by altering the temper, as well as chipping of the edge while milling. You will have better results with a cut off wheel where you can’t view any mesh on the wheel, as we described in the paragraph above.
Most cut off wheels for chop saws are available at your local home or industrial supply center. If you would like to purchase the cut off wheel we use, they are offered single packs of five per box. Please feel free to contact us, we would be glad to help you experience better overall cuts on your steel knife blanks.
