Negative rake scraper angle for box making

[Michael Perez]

Hello,I hope you’re all doing well.
I’m planning to create a new collection of boxes and want to add a negative rake scraper to help clean the inside of the boxes from gouge marks and refine the finish. Initially, I considered the D-Way negative rake scraper but decided instead to buy and modify a Robert Sorby square scraper to fit my needs.
Before I start shaping the scraper, I’m seeking advice on the most effective angles. There seems to be a wide range of preferences and suggestions, even among experienced turners. My understanding is that the choice of angle is less than 80° included angle, however D-Way uses angles like 20°/70° that is an exception to the rule maybe because the kind of steel and treatment.
Given that I work with different kind of woods like Peruvian walnut and purpleheart, I’m considering starting with a simple 25° angle on both sides, resulting in a 50° included angle. This would also allow me to flip the scraper and use the other side if needed.
I’d appreciate any insights or recommendations you have based on your experience.

Thank you!

 

[Gabriel Hoff]

I have the D-Way and I LOVE it! You should reconsider purchasing that one. I do grind it to 20/70 and it works really well, very sharp and controlled. It will work well on the purpleheart and walnut as those are harder woods. Just keep the scraper handle a little but above centerline and you should have no issues with catches. I have attached a photo of my D-Way scraper.....

 

[Michael Perez]

I have the D-Way and I LOVE it! You should reconsider purchasing that one. I do grind it to 20/70 and it works really well, very sharp and controlled. It will work well on the purpleheart and walnut as those are harder woods. Just keep the scraper handle a little but above centerline and you should have no issues with catches. I have attached a photo of my D-Way scraper.....View attachment 66669

Thanks for your response! I’m definitely considering getting a negative rake scraper from D-Way in the future. I’d also like to try a Thompson bowl gouge and a Carter & Son skew (I just ordered a 1” C&S skew). Woodturning can be quite expensive, especially with all the tools and accessories. I started with gouges from Crown and Robert Sorby, but I’m confident I’ll upgrade my tools when I have the opportunity. For now, I’ll be using my Robert Sorby blank.
Greetings

 

[Aaron Harris]

Michael-I love my D-way NRS's. That said, the great platter turner Tom Wirsing grinds his NRS scrapers to 22.5 degrees on each side IIRC. He finish scrapes every single surface, and doesn't power-sand, refreshing the burr edge constantly on 600 CBN I believe. His are of some super-hard steel, maybe Thompson? (I will ask him when he does a platter demo and class for our club next month). Of course you may prefer a different grind deep inside a box. Part of the fun is discovering what grinds work best for your hands and the way you make cuts.

 

[Michael Perez]

Michael-I love my D-way NRS's. That said, the great platter turner Tom Wirsing grinds his NRS scrapers to 22.5 degrees on each side IIRC. He finish scrapes every single surface, and doesn't power-sand, refreshing the burr edge constantly on 600 CBN I believe. His are of some super-hard steel, maybe Thompson? (I will ask him when he does a platter demo and class for our club next month). Of course you may prefer a different grind deep inside a box. Part of the fun is discovering what grinds work best for your hands and the way you make cuts.

Thanks so much. It’s definitely a long learning process, but the beauty is in enjoying that journey as you mentioned.

 

[Bill Alston]

We had a demo at my club some time back and the demonstrator was using one of his signature negative rake scrapers. I don’t know the angle but it was very sharp. You can see it here:

Jason Breach Box Refinement Tool Round Nosed Tool - 19mm(3/4")

These fine tools are the result of collaboration between Jason Breach, one of the country's leading woodturners, and the well respected Sheffield toolmaker, Henry Taylor. Jason specialises in box making and for many years has felt the need for some...

www.axminstertools.com

He explained that unlike normal scrapers that should be used slightly nose down to prevent catches, negative rake scrapers are quite safe used horizontally. I’ve not used a NRS much so no real experience. What I did start to do some time ago was to press, rather than grind a burr on my scrapers with a Burnisher. I made my own version of this:



The resultant burr lasts longer and it can be refreshed on the Burnisher another once or twice before needing to go back to the grinder. My jig sits securely on the bed of the lathe for quick and easy access.

 

[Michael Perez]

We had a demo at my club some time back and the demonstrator was using one of his signature negative rake scrapers. I don’t know the angle but it was very sharp. You can see it here:

Jason Breach Box Refinement Tool Round Nosed Tool - 19mm(3/4")

These fine tools are the result of collaboration between Jason Breach, one of the country's leading woodturners, and the well respected Sheffield toolmaker, Henry Taylor. Jason specialises in box making and for many years has felt the need for some...

www.axminstertools.com

He explained that unlike normal scrapers that should be used slightly nose down to prevent catches, negative rake scrapers are quite safe used horizontally. I’ve not used a NRS much so no real experience. What I did start to do some time ago was to press, rather than grind a burr on my scrapers with a Burnisher. I made my own version of this:

View attachment 66694

The resultant burr lasts longer and it can be refreshed on the Burnisher another once or twice before needing to go back to the grinder. My jig sits securely on the bed of the lathe for quick and easy access.

Hello, thank you so much for all the recommendations and for sharing your experience. I just looked into the gouge you mentioned and watched a video about that tool. The presenter mentioned that the lower bevel is around 45° to 55°. I ground the top at 25° and was about to grind the bottom to the same 25°, but I’m wondering if I should go steeper. I’m not sure what would be the better choice.
Greetings

 

[Bill Alston]

I can’t help Michael, except to say the scraper was passed around the audience to have a look, and it felt very sharp to me.
On the rare occasions I’ve tried/used a NRS I’ve sharpened the top and bottom angles the same, just to make things easier. I’m not alone in this but I don’t know how it compares to using different angles? Let us know how you get on.

 

[robo hippy]

I have almost all D Way NRSs. In part because Dave Schweitzer and Jimmy Allen are friends. I do prefer the M42 or V10 which Doug sells. I don't think Doug makes the smaller tools like D Way does, but don't know for sure. All of my NRSs are ground to 30/60 degrees on my old robo rests, which turns out to be 25/55 degrees actually. I do prefer that grind to the skew chisel grind, which does work, but the burr is gone in seconds compared to a burnished burr (small diameter carbide rod) which can last for several minutes at least. They can leave a surface that 400 grit roughs up. One can never have too many tools! I do love the box tool rest from D Way as well. I have many different profiles/shapes. Some more round nose, a few square nose, but angled back a bit on the inside for square bottom boxes, some with a small radius on the left side, some on the right side, and many other variations. I had Jimmy send me a bunch of blanks so I could experiment....

robo hippy

 

[Michael Perez]

I can’t help Michael, except to say the scraper was passed around the audience to have a look, and it felt very sharp to me.
On the rare occasions I’ve tried/used a NRS I’ve sharpened the top and bottom angles the same, just to make things easier. I’m not alone in this but I don’t know how it compares to using different angles? Let us know how you get on.

Thanks so much, definitively you’ve helped me a lot and of course I’ll be posting my negative Scraper and my progress

 

[Michael Perez]

I have almost all D Way NRSs. In part because Dave Schweitzer and Jimmy Allen are friends. I do prefer the M42 or V10 which Doug sells. I don't think Doug makes the smaller tools like D Way does, but don't know for sure. All of my NRSs are ground to 30/60 degrees on my old robo rests, which turns out to be 25/55 degrees actually. I do prefer that grind to the skew chisel grind, which does work, but the burr is gone in seconds compared to a burnished burr (small diameter carbide rod) which can last for several minutes at least. They can leave a surface that 400 grit roughs up. One can never have too many tools! I do love the box tool rest from D Way as well. I have many different profiles/shapes. Some more round nose, a few square nose, but angled back a bit on the inside for square bottom boxes, some with a small radius on the left side, some on the right side, and many other variations. I had Jimmy send me a bunch of blanks so I could experiment....

robo hippy

Thank so much. I really want to take a decision today and you’ve helped me, since I already have the 25º top angle I’ll grind a 55º beneath angle and start trying it .I need to learn more the principles of angles, the importance of the beneath and top angles, how to combine them and what results could I achieve.

 

[Mike Novak]

I suspect that the best angles depends on what you want to do with it. Mine is at about 20 top and bottom, 30 included angle on edge. I use for finishing.

I suspect that generally a smaller top angle with bigger included angle would be better for stock removal and a bigger top angle with smaller included angle would be better for finishing. Could anyone comment on this hypothesis?

 

[John Whitley]

It's worth noting that there are some different schools of thought regarding scraper application, which affect the scraper's overall form and grind style. For example some scrapers (e.g. Ashley Hardwood's line) are intended solely for surface refinement/finishing cuts, held level, and with full tool rest support. Traditional scrapers and the D-Way/Boxmaster negative rake scraper line are used for anything from hogging away material (think box hollowing) to fine shaping, with more versatility in edge presentation. I recommend giving the D-Way negative rake scraper sharpening video a watch.You'll see a range of scraper usage, and Eric Lofstrom's tips on refining scraper edges and burrs are priceless, particularly in how he relates the resulting edges to the type of wood (or other turning material) that you're working with. Especially valuable given your stated interests in wood species.

 

[Kevin Jenness]

Cyndi Drozda sells some box scrapers made by Doug Thompson to her design that may work for you.

 

[Bill Alston]

It's worth noting that there are some different schools of thought regarding scraper application, which affect the scraper's overall form and grind style. For example some scrapers (e.g. Ashley Hardwood's line) are intended solely for surface refinement/finishing cuts, held level, and with full tool rest support. Traditional scrapers and the D-Way/Boxmaster negative rake scraper line are used for anything from hogging away material (think box hollowing) to fine shaping, with more versatility in edge presentation. I recommend giving the D-Way negative rake scraper sharpening video a watch.You'll see a range of scraper usage, and Eric Lofstrom's tips on refining scraper edges and burrs are priceless, particularly in how he relates the resulting edges to the type of wood (or other turning material) that you're working with. Especially valuable given your stated interests in wood species.

Thanks for that, a very interesting video. 😉

 

[Kent Reisdorph]

We had a demo at my club some time back and the demonstrator was using one of his signature negative rake scrapers. I don’t know the angle but it was very sharp. You can see it here:

Jason Breach Box Refinement Tool Round Nosed Tool - 19mm(3/4")

These fine tools are the result of collaboration between Jason Breach, one of the country's leading woodturners, and the well respected Sheffield toolmaker, Henry Taylor. Jason specialises in box making and for many years has felt the need for some...

www.axminstertools.com

He explained that unlike normal scrapers that should be used slightly nose down to prevent catches, negative rake scrapers are quite safe used horizontally. I’ve not used a NRS much so no real experience. What I did start to do some time ago was to press, rather than grind a burr on my scrapers with a Burnisher. I made my own version of this:



The resultant burr lasts longer and it can be refreshed on the Burnisher another once or twice before needing to go back to the grinder. My jig sits securely on the bed of the lathe for quick and easy access.

I use this. $27 at Amazon. The Veritas definitely has some advantages and isn't much more money.

 

[Bill Alston]

I bought the Veritas 10° pin, it was £14.99 at the time I think. I made the rest from a piece of steel in my scrap bin. It’s made to be a snug fit when dropped into the ways of my lathe. You can apply a lot of pressure to produce a good size burr if required.

 

[robo hippy]

My theory on burr durability is that you need a certain amount of metal under the burr to support it, which is the reason that I use the 55 degrees on the bottom. A standard card scraper burnishing tool does work on M2 high speed steel. The triangle version works better, I am guessing because of the smaller surface area. With the M42 HSS and the V10, it is extremely difficult to get the burr raised, which is why I use carbide. A small router bit will work fine. I think the Veritas burnishing tool you screw down to a bench top is carbide, but not handy to keep in your pocket. It really doesn't take much pressure to raise a burr, more often, just repeated strokes to turn it gradually rather than in one pass. Note here, have your thumb on the tool you are burnishing and curl your fingers and hand to make the pass. I have slipped several times when burnishing, and your hand and fingers will always go across that freshly turned burr...... ALWAYS!

robo hippy

 

[Michael Perez]

I suspect that the best angles depends on what you want to do with it. Mine is at about 20 top and bottom, 30 included angle on edge. I use for finishing.

I suspect that generally a smaller top angle with bigger included angle would be better for stock removal and a bigger top angle with smaller included angle would be better for finishing. Could anyone comment on this hypothesis?

Thank you so much! I’m planning to use it for finishing boxes and cleaning up gouge marks. I initially intended to start with a 25° top bevel and a 55° bottom bevel, but after checking, I ended up with around 27° and 60°. Now I’m working on the handle.

 

[Michael Perez]

It's worth noting that there are some different schools of thought regarding scraper application, which affect the scraper's overall form and grind style. For example some scrapers (e.g. Ashley Hardwood's line) are intended solely for surface refinement/finishing cuts, held level, and with full tool rest support. Traditional scrapers and the D-Way/Boxmaster negative rake scraper line are used for anything from hogging away material (think box hollowing) to fine shaping, with more versatility in edge presentation. I recommend giving the D-Way negative rake scraper sharpening video a watch.You'll see a range of scraper usage, and Eric Lofstrom's tips on refining scraper edges and burrs are priceless, particularly in how he relates the resulting edges to the type of wood (or other turning material) that you're working with. Especially valuable given your stated interests in wood species.

Hello, thank you so much for the detailed explanation. I just checked out Ashley Harwood’s line, and it does seem quite short. After reading your response again, I now understand it’s mainly for surface work. I’ve seen D-Way’s videos, which is why I’m curious to try their scrapers. I’m now starting my first shaping with a Robert Sorby square scraper that I purchased as a blank.

 

[Michael Perez]

Cyndi Drozda sells some box scrapers made by Doug Thompson to her design that may work for you.

thanks! Yeah, I’ve seen those too, and I’m really curious about Thompson tools as well. I’ve never tried them, but I keep hearing great things.

 

[Michael Perez]

I bought the Veritas 10° pin, it was £14.99 at the time I think. I made the rest from a piece of steel in my scrap bin. It’s made to be a snug fit when dropped into the ways of my lathe. You can apply a lot of pressure to produce a good size burr if required.

That’s great! I just checked the Veritas scraper burnisher, and it’s around $58, so after importing to my country, it will be about $80. I really appreciate you sharing this info—I’ll definitely check out the pin. Thanks again

 

[Michael Perez]

My theory on burr durability is that you need a certain amount of metal under the burr to support it, which is the reason that I use the 55 degrees on the bottom. A standard card scraper burnishing tool does work on M2 high speed steel. The triangle version works better, I am guessing because of the smaller surface area. With the M42 HSS and the V10, it is extremely difficult to get the burr raised, which is why I use carbide. A small router bit will work fine. I think the Veritas burnishing tool you screw down to a bench top is carbide, but not handy to keep in your pocket. It really doesn't take much pressure to raise a burr, more often, just repeated strokes to turn it gradually rather than in one pass. Note here, have your thumb on the tool you are burnishing and curl your fingers and hand to make the pass. I have slipped several times when burnishing, and your hand and fingers will always go across that freshly turned burr...... ALWAYS!

robo hippy

Thank you so much! I really appreciate your help and the time you’ve taken to explain everything in detail, especially considering the type of metal and giving me safety recommendations. When I buy from the USA, I’ll try the Veritas pin and make a base as Bill mentioned. I have a very thin 2mm carbide bit that broke, and I also have a DMT card at 600 grit—hopefully, this will help me for now.

 

[Michael Perez]

Hello everyone, this my progress, now I keep working in the handle

 

[Michael Perez]

I use this. $27 at Amazon. The Veritas definitely has some advantages and isn't much more money.

View attachment 66722

Thanks, It’s nice and made in USA. I have something similar is a rod that I bought from Ron Hock for card scrapers, I don’t know if it will also work for my HSS woodturning scraper.
Greetings

 

[Kevin Jenness]

I use this carbide rod burnisher from Lee Valley for turning a burr on scrapers. burnisher The fixture mentioned above works but it enables a lot of leverage and a large burr which is not really what you want for finishing.

 

[Michael Perez]

I use this carbide rod burnisher from Lee Valley for turning a burr on scrapers. burnisher The fixture mentioned above works but it enables a lot of leverage and a large burr which is not really what you want for finishing.

Thanks so much. I have one tungsten carbide end mill broken, I think is 2mm, tomorrow I’ll look for it and take a picture maybe I can make a handle for it.

 

[Adrian Wilson]

Hello, thank you so much for all the recommendations and for sharing your experience. I just looked into the gouge you mentioned and watched a video about that tool. The presenter mentioned that the lower bevel is around 45° to 55°. I ground the top at 25° and was about to grind the bottom to the same 25°, but I’m wondering if I should go steeper. I’m not sure what would be the better choice.
Greetings

I know you are already into your project, but just to say I bought this tool (Jason Breach NRS) recently, and like it. I don't have enough time with it to have any great insight, and it's my first NRS, but from what I see so far I don't see any need to vary the grind angles.

 

[Bill Blasic]

When you speak of scrapers for boxes I mainly think of the Jimmy Clewes Box Scraper. These are Thompson tools and I had Doug grind this one up for me (pics 1 thru 4). You can see that it is not negative ground but it has a very slight roll from left to right and is cut on the side to give ability to cut the inside wall. What is unique is that you can go across the bottom right up to the wall and continue up for a nice tight corner. The second tool (pics 5and 6) is a Thompson negative rake round scraper again done by Doug. Cutting with these tools is a little different as the box scraper is held at a downward angle where the negative rake scraper will work catch free at any angle

 

[Bill Blasic]

Pics 5 and 6

 

[Michael Perez]

When you speak of scrapers for boxes I mainly think of the Jimmy Clewes Box Scraper. These are Thompson tools and I had Doug grind this one up for me (pics 1 thru 4). You can see that it is not negative ground but it has a very slight roll from left to right and is cut on the side to give ability to cut the inside wall. What is unique is that you can go across the bottom right up to the wall and continue up for a nice tight corner. The second tool (pics 5and 6) is a Thompson negative rake round scraper again done by Doug. Cutting with these tools is a little different as the box scraper is held at a downward angle where the negative rake scraper will work catch free at any angle

Wow, when I first started looking for a scraper, I was torn between the Jimmy Clewes, D-Way, and Robust box scrapers. But I decided to invest in a premium skew first since I use it the most.(Carter and son 1" skew)
Thanks so much for the picture, explanation, and recommendations. There’s definitely a lot to learn, and with practice and experience, you find what works best for your preferences and the specific task at hand.
greetings

 

[Michael Perez]

I know you are already into your project, but just to say I bought this tool (Jason Breach NRS) recently, and like it. I don't have enough time with it to have any great insight, and it's my first NRS, but from what I see so far I don't see any need to vary the grind angles.

Thanks so much! I didn’t know about Jason Breach, I’ll check out his tools. For most of my gouges, I also keep the factory grind and haven’t had the chance or need to change it. However, I’d like to take the time to experiment with different angles to better understand how they work.

 

[robo hippy]

Any piece of carbide should work for a burnisher. Given the cost of importing, I am sure your 2mm piece will work. We gringos need to get on the metric system.....

robo hippy

 

[Michael Perez]

Any piece of carbide should work for a burnisher. Given the cost of importing, I am sure your 2mm piece will work. We gringos need to get on the metric system.....

robo hippy

This is my carbide tip in inches.

 

[robo hippy]

The pins I got were 1/8 inch. Eric Lofstrom liked a slightly smaller one. That pin should work fine.

robo hippy

 

[Michael Perez]

The pins I got were 1/8 inch. Eric Lofstrom liked a slightly smaller one. That pin should work fine.

robo hippy

Thanks so much after I finish my handle I’ll be making a handle for the endmill bit.
Greetings

 

[Bill Alston]

I made a 10° tapered pin from some O1 tool steel for a guy at my club to try using as a Burnisher but he’s not reported back. I may have to make another to try myself. After turning and polishing the pin I hardened it but didn’t temper it, I left it “glass hard”. As such the Rockwell hardness should be slightly higher than HSS? The pin is 10mm diameter at the base.

 

[Don Wattenhofer]

Any piece of carbide should work for a burnisher. Given the cost of importing, I am sure your 2mm piece will work. We gringos need to get on the metric system.....

robo hippy

You maybe are right about that but carbide mills or router bits usually have a polished shank verses the slightly rough surface on a carbide blank.
About 15 years ago I bought some scrap "up cut / down cut" CNC router bits that had been sharpened beyond their useful range for about $20.00 per pound. I have been using them ever since and they do not show any surface scratches.

The tool to the right of the burnisher is the only one with a negative rake grind and the only one that would be commonly used flat on the tool rest. The second and third from left work well in end grain vessels doing a shearing cut on rounded inside bottoms by rotating the tool off the flat but never flat. The use of the burr is dependant on the way you present the burr/cutting edge to the work. I recently made a video with my Iphone but I have not figured out how to make one of those recurring videos that are often seen on this forum.

 

[Kent Reisdorph]

I have not figured out how to make one of those recurring videos that are often seen on this forum.

Al can probably give you the specifics, but Google "video to GIF".

 

[hockenbery]

video with my Iphone but I have not figured out how to make one of those recurring videos that are often seen on this forum.

Those are gif photos.
Easiest for me is finding a 14 year old and have them set it up.

I can tell you how I did it but probably don’t know enough to tell you how
I make gifs on the iPad. Just set up my phone to do it.

I installed a shortcut called “make gif” it’s not a regular App its a widget whatever that is.

I Opened the shortcuts app then select all shortcuts then select “make gif”. It is pink on my phone.

I save a 4-6 second video clip using iMovie in photos. That’s where they go if you do the save.
Click “make gif” it looks in the photos for any videos. I pick the iMovie I saved
Watch a preview and save it.
Then I have the gif in photos.

The widget has other features. It lets you select part of a too long video but I haven’t gotten good results with that
Easier for me to select the video part in iMovie and save that