The Evolution of Turning Man-Made Materials

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Since the beginning of woodturning time, the woodturners’ worst enemy has been a dull edge on their turning tool. If a conventional turning tool was not sharpened properly, or the edge did not hold up, the tool would not cut and surface finish would be sacrificed. Never before has the sharpness of the tools edge been more important than with the recent enormous surge in popularity in turning man-made materials such as resins like Alumilite or Polyester Acrylic.

Man-made materials, or resins can be very brittle and hard to turn with tools that do not hold a sharp edge. Carbide tipped turning tools have quickly become the go to tools for turners of these materials due to the fact that the edge on a carbide insert can be ground to an extremely sharp edge, and will typically hold up as a sharp edge by a factor of at least 10x that of the edge on a high speed steel tool.

Since the inception of carbide tipped tools in woodturning in 2008, carbide tools have been touted as being the easiest tools to learn, and the safest tools to use. The tools have a very short learning curve that includes three simple rules to follow; 1) always hold the tool flat on the toolrest. Never tip the tool on an angle to the left or the right. 2) Always hold the tool horizontal, or parallel to the ground, and 3) introduce the cutting edge of the tool on center with the workpiece. As long as these three rules are always followed, carbide tools are proven to be the safest tools to use.

As more and more people enter into turning man-made materials with carbide tipped tools, a new challenge was found with the way the tools were being used. Turners quickly learned that carbide inserts, with their long lasting sharp edge can actually cut too aggressively for some materials and can cause other issues like chipping, or catches. Severe catches could lead to blow-outs in resin pen blanks, ruining a project completely.

In an attempt to remedy the issue of cutting too aggressively, turners have tried many things including tipping the tool on a variety of angles. The most successful of these attempts was found to be lifting the back end of the tool up in the air so that the top surface of the carbide cutter would taper down to the workpiece. Many turners experiencing the issue of chipping and catches reported that by taking the angle off of horizontal, the tool would cut less aggressively and the chipping could almost be controlled. The theory behind tapering the top of the carbide is what is known as rake. With the tools being tapered downward to the workpiece, they were introducing a negative rake angle on the tool. The caution in turning with this method comes from the fact that this was breaking one of the three rules of turning with carbide tools that makes them the safest tools to use.

Recently, this issue was solved with the introduction of negative rake carbide inserts. These new inserts have the optimum tip angle geometry engineered in so that the tool can once again be used in a horizontal fashion. The benefit of the negative rake carbide cutters is that they virtually eliminate catches and chipping in resin materials and give a smooth finish to most woods while still employing the three rules of turning with carbide tipped tools. Since their introduction in August of 2018, the negative rake cutters have taken the market by storm as the way to successfully turn man-made materials.
 
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cozee

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Good information. However, I am not sure where the inception date of of 2008 of carbide tipped tools came from. I know the introduction of woodturning turning tools with replaceable carbide bits, or cutters, was around the date mentioned though. Several years ago I was gifted the old Atlas/Craftsman wood lathe and tools of a close friend's father who had long passed. He stated his Dad had not turned since the late Seventies. Several of the tools, many handmade, had been braze tipped with carbide.
 

mecompco

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I suppose I should try a negative rake cutter, but honestly, I've not had a problem using my favorite R2 cutters in the diagonal orientation when necessary. I tend to swap back and forth between cutting and scraping. Like anything, I think it's mostly practice. Just what I do, everyone's MMV.
 

Pierre---

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Chris, I guess it would have been fair, before or after this long advertising for Easy Wood Tools, to say you are the owner.
Anyway, I wish you good luck selling your tools. They avoid us to feel the proper - but soooo difficult - way to hold them: every invention that take us away from learning the hard way to be craftsmen is good to take. :)
 

randyrls

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I have no problem with normal carbide tooling on the hardest TruStone or chippiest acrylic. I just adjust the tool geometry and position relative to the blank.
 

leehljp

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I agree with carbide inserts for beginners because of the jump it allows them to go into pen making without having to invest in and learn proper sharpening procedures for HSS. And in general for most pen turners, even experts, it will work, but it is not quite the end all that is purported in your description. I learned several years ago that literally razor sharp blades is a necessity in some cases for fine work (I did not say razor THIN blades as some try to make fun of). I have 3 carbide cutters and whether round or square (or radiuses square) I haven't found one yet that I can not pick up the tool by squeezing the carbide insert blade between my fingers, but I dare anyone to try to squeeze the blade of my skew against the opposing side and pick it up without cutting your finger. AND my HSS does last through fine turning to the point that NO SANDING is needed. (Anyone here familiar with fine wood finishes with hand scrapers that are so much better than sandpaper? A properly sharpened HSS does that on a pen or bowl). And I can go about 30 minutes of turning before re-sharpening is needed, however, I do swipe it twice, about once a minute against .5 micron sandpaper to keep the edge razor sharp.

Most people don't need that kind of sharpening and with new techniques, carbide is getting to be almost as sharp as HSS can get. But not quite there yet.

Again, I have carbide insert, use it and recommend it.

Chris, If you want to advertise your tools, just go ahead and post it in "Vendors".
 
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