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Post by chuckb on May 20, 2019 13:45:17 GMT
Approximately 35 years ago my brother invested in a set of 10 Sorby turning chisels for a project we were working on. These chisels were far better than the tools I was working with. I am now in possession of the set and they need sharpening. Since the steel composition determines the best grinding wheel to use l want to know when Sorby began using HSS for their chisels. I could do a spark test but hope there is a more definitive answer.
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Post by Pete on May 20, 2019 21:53:39 GMT
Hi chuckb First question since I became moderator, and I can't answer it  But I have bumped it up the line, and hopefully you will have your answer soon. |
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Post by Clive Brooks on May 21, 2019 7:15:33 GMT
Hi chuckb...Thank you for your great question...As you say in your post the spark test would tell you as HSS would give orange glowing Star like sparks where as Carbon will give sparkler / firework style sparks...Please can you send me images of the tools and I will be able to tell you if they are Carbon or HHS...Cheers Clive
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Post by chuckb on May 22, 2019 20:52:10 GMT
Clive,
I am attaching two images. One shows the original box label with the faded numbers enhanced. The other is of the chisels themselves. I will clean them up once sharpened. I just put in an online order for a Sorby 3/8" Bowl Gouge.
chuck
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Post by phoneman on May 23, 2019 8:44:53 GMT
Well done, Pete. Being a good moderator does not mean that you have to know all the answers, as long as you have a good pipeline to those who do know.
Clive, in the past, the typical Sorby response has often been to request the poster send an email to Sorby sales. That defeats the benefit of a forum by presuming that the poster is the only one interested in the subject.None of these questions are proprietary business information. Please share the answers online.
My turning tools are a combination of carbon and high speed steel. I inherited my grandfather's 1930s vintage set of Sears Craftsman eight carbon steel tools. Over the years I have added about the same number of mostly Robert Sorby high speed steel individual tools. In addition to sentimental value, the rarely used tools in the carbon set are quite adequate for occasional service. They do not need the endurance of the heavy lifting tools.
One of the side effects of my spark and dust free, cool grinding wet grinder is no sparks. Sorry, I can't help you with that. On a practical level, I don't know why you would need different grinding wheels for high carbon and high speed steel. My standard test of how a wheel cuts is to place a metal lathe bit in my square edge jig at a 30° bevel and grind for five minutes. CBN, diamond, and the 46 grit Norton 3X wheels do remove metal more quickly than the aluminum oxide wheel which came with my wet grinder. However, as Pete has correctly stated, it is often more practical to purchase a second tool of the desired shape than to do major reshaping. Routine sharpening of hss is well within the parameter of aluminum oxide wheels as long as you avoid the ibexpensive hardware store gray wheels which typically come with new grinders.
There is a mistaken idea that carbon steel tools should not be sharpened on CBN wheels. Mild, not heat treated steel will clog CBN wheels. (This can be cleaned up by grinding on hss steel.) However, my other test procedure involves 3/4” high carbon steel bench chisels. I have never had a problem with these, sharpened wet (with anti oxidant) or dry.
I am curious to read Clive's answer.
Phoneman
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