finish scraping

[Holmes Anderson]

I turned for over 35 years before anyone "invented" the current negative rake scraper. I bought a negative rake scraper, and now it's in my misfit, unused tool drawer. Most of us used the Irish grind bowl gouge, skew, or freshly ground scraper to do fine scraping in the past. I still think a fine burr on a big scraper is a better tool. A negative rake scraper is NOT a necessity. It is a great way to spend money if that is your goal.

+1. Shear scraping yields a better surface both on the inside and outside of a bowl.

 

[Kent Reisdorph]

+1. Shear scraping yields a better surface both on the inside and outside of a bowl.

I stopped trying to shear scrape inside bowls with an Ellsworth grind. It doesn't work. Do you mean with a scraper?

 

[Holmes Anderson]

I stopped trying to shear scrape inside bowls with an Ellsworth grind. It doesn't work. Do you mean with a scraper?

Yes, shear scraping with a round nose scraper on the inside of the bowl and with a square end scraper reground into a refiner on the outside of the bowl.

 

[robo hippy]

I have seen a number of turners who use a swept back grind on the inside of a bowl with the handle held level. That is NOT a shear scrape, which to me means held at an angle. At best, that use of a swept back gouge would be more of a NRS than any kind of shear scrape. I do have one video dedicated to that topic.

robo hippy

 

[Neil S]

I have some HSS, some M42 and a lot of 10V steel and I have never did a test as to how long they last as I have left that for others. And there have been many of those and it stands that in terms of lasting in sharpness the ongoing conclusion is that (not including 15V) its 10V, then M42 and then HSS. Remember that when a pro tells you that what he is using is the best its because he's getting something for using them or he is selling them.

I'm one of those that has done a lot of my own testing of the different woodturning tool steels and can say with some confidence that tool performance can depend partly on what it is being used for. With heavy push cuts in very hard wood I found little difference between V10 and 15V....

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But M42 did just a little less well on the same test runs...

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However, with fine shearing cuts the M42 outperformed V10...

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Because of its fine carbide structure the M42 also benefited more than 10V from being ground on a finer #1k grit wheel for turning medium to harder woods, as does Tungsten Carbide...

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In my testing V15 always outperformed V10, but only marginally at times. Whether it is worth the extra cost is a judgement for each turner. I've been using V15 for decades now and I have never found it to be chippy and I do spend more time looking at edges under magnification than many other turners.

So, it is not a s simple as this steel is better than that steel. In most non-production workshops there will be very little difference noticed by most turners between these steels. If you want a quantum improvement you have to go to very fine-grained TC and the diamond grinding required with that.

I'm a little less cynical than Bill about pro-turner's recommendations, they have to make a living, but I always reserve my opinions until I've done my own testing. I've lived through all of the hype over the decades with each successive new development in tool steel and I ignore almost everything that retailers 'spruke'.

I think it is Cindy Drosda who says, 'we are just one tool away from turning greatness'. In my time basic HSS was the most significant development in turning tool steels and turning greatness has been achieved with just that by many of the great turners. IMO, the newer super steels are nice to have, but in no way essential to great turning. I believe that @Odie on this forum only uses vanilla HSS tools and it certainly hasn't prevented him from doing some excellent work.