I would love to see a video designated to the different uses of scrapers. You use a scraper a lot more than I ever have and would like to see it in more depth, thank you
Hello Richard, I really enjoy your videos. As a matter of fact I still refer back to a video you did in 1985 and will continue to as long as my vcr lives on.
I had no idea that the scraper could have such a steep angle. I was grinding mine upside down to get a burr that would last more than a few minutes, but I’m wondering if I steepen the angle maybe it would last even longer?
@@RichardRaffanwoodturning thank you so much for your response. Much much respect to you sir for publishing these awesome videos. Just made a spinning top today after watching your video as a matter of fact. Although I just cannot use the skew chisel without bad catches. That said, a bowl and a spindle gouge did magic.
No is the short answer. The 80-grit CBN wheel I grind/sharpen on absorbs most of the heat, but overheating doesn't affect HSS provided you don't dunk it. Even when I did I didn't find it made much difference. Sharpening carbon steel on a friable white wheel, is a different matter and it's much easier to burn the steel. The secret to sharpening on a HS grinder is not to push the tool hard against the wheel, just as in turning when you shouldn't push the tool hard against the wood. You let the wood or wheel come to the tool.
Richard I notice you have only one CBN and one coarse carbide wheel. What grade is the CBN please Also could you suggest some good brands of scrapers and perhaps appropriate sizes width and thickness as there seems to be some wide but pretty thin scrapers around. Once again thanks so much for educating us. Cheers
The CBN is 80 grit. The gray wheel has no label but is probably also 80, whereas 60 grit or even 36 would be better for shaping. Most of my tools are Henry Taylor who make the Raffan Signature Tools. I also use Sorby, D-Way, and Gurtool. Here are my essential tools: ua-cam.com/video/qAz1FfAtqmE/v-deo.html
I think putting a negative rake on a scraper is a complete waste of time. This partly because I’ve never come across anything a negative rake does that a standard scraper can’t do as well or better. Their chief benefit is that they are more difficult to catch, although not impossible. To achieve a negative rake all you have to do is raise the tool handle and possibly the rest. On internal cylinders I find a standard square-section scraper is far superior, especially for getting into corners when turning boxes, because the bevels tend to ease the cut towards centre. The best box tool is a bedan with a slightly radiused edge used as a scraper.
Grinding as you see here produces a burr on top. HOw big a burr depends on how hard you push the tool against the grinding wheel. The less pressure the better the edge.
thank you for the video, I have a question for years. I dont understand the reason for honing with diamond only the upper face "to refresh" recommended from all, including Robert Sorby videos. If you honing only the upper face, the burr dissapears and I dont kwnow if the scraper is sharper again. Not convince me. Whats wrong with my appreciation. Thanks for your proverbial patience.
Honing the top of a scraper before regrinding removes the old burr. The advantage when sharpening on a CBN wheel (where there are no sparks) is that honing leaves a highlight on the end of the tool. The highlight vanishes when the edge is sharp.
@@RichardRaffanwoodturning yes I understand your video, before regrinding, but the maker's advice is "after use, honing only the top",... for the RS Hollowmaster cutters, for example, my question is if you agree that only the top refresh the edge.
@@tallerpinocho Here's my 2 penneth worth: The Sorby Hollowmaster has small, (admittedly) replaceable, HSS tips. If you take it to the grinder every time you wish to renew the edge, you're going to get through them very quickly and will constantly find yourself buying replacements. Also, it's worth noting that you don't need a burr on a scraper to make it cut. Look at the carbide tips you can get these days, they cut without a burr - some would argue a burr on HSS helps helps (personally, I'm not sure I agree), but the point is that by dressing the top edge of the tool with a diamond hone, you can get a good edge AND your tool will last much longer...
I think grinding a negative rake on a scraper is waste of good tool steel: I've never seen anything that can't be done with a single bevel scraper provided the angle between the surface being cut and the top of the tool is less than 90 degrees. There are plenty of situations where a single bevel square-end scraper is vastly superior to a negative rake - for instance turning an internal cylinder or corner. A negative rake for cutting is easily accomplished by adjusting the height of the tool rest and raiing the tool handle.
I would love to see a video designated to the different uses of scrapers. You use a scraper a lot more than I ever have and would like to see it in more depth, thank you
Hello Richard, I really enjoy your videos. As a matter of fact I still refer back to a video you did in 1985 and will continue to as long as my vcr lives on.
Thanks for your time, and your tips are very much appreciated.
Just found your channel. Really enjoying your videos. You're a great teacher.
Thank you Richard. I value your experience and suggestions!!!
Thanks for you reply to my query about your Signature series scraper, now I understand your deign, must try and replicate from my 75 degree bevel
Thanks
I had no idea that the scraper could have such a steep angle. I was grinding mine upside down to get a burr that would last more than a few minutes, but I’m wondering if I steepen the angle maybe it would last even longer?
Great video richard - if I may ask - what grit are your wheels in this video?
Both wheels are 80 grit. I'd prefer a 36 grit carborundum for shaping but will use up the existing wheel first.
@@RichardRaffanwoodturning thank you so much for your response. Much much respect to you sir for publishing these awesome videos. Just made a spinning top today after watching your video as a matter of fact. Although I just cannot use the skew chisel without bad catches. That said, a bowl and a spindle gouge did magic.
Sir, I have mot seen you cool any tools while grinding; are you not concerned for the temper?
No is the short answer. The 80-grit CBN wheel I grind/sharpen on absorbs most of the heat, but overheating doesn't affect HSS provided you don't dunk it. Even when I did I didn't find it made much difference. Sharpening carbon steel on a friable white wheel, is a different matter and it's much easier to burn the steel. The secret to sharpening on a HS grinder is not to push the tool hard against the wheel, just as in turning when you shouldn't push the tool hard against the wood. You let the wood or wheel come to the tool.
Did a search online and could not find a source for a round bar tool rest for the grinder. Do you know where you got yours? or have a resource?
Make one.
Richard I notice you have only one CBN and one coarse carbide wheel. What grade is the CBN please Also could you suggest some good brands of scrapers and perhaps appropriate sizes width and thickness as there seems to be some wide but pretty thin scrapers around. Once again thanks so much for educating us. Cheers
The CBN is 80 grit. The gray wheel has no label but is probably also 80, whereas 60 grit or even 36 would be better for shaping. Most of my tools are Henry Taylor who make the Raffan Signature Tools. I also use Sorby, D-Way, and Gurtool. Here are my essential tools: ua-cam.com/video/qAz1FfAtqmE/v-deo.html
Thank you for sharing. How do feel about using the negative rake scraper and what is your preferred angle for it?
I think putting a negative rake on a scraper is a complete waste of time. This partly because I’ve never come across anything a negative rake does that a standard scraper can’t do as well or better. Their chief benefit is that they are more difficult to catch, although not impossible. To achieve a negative rake all you have to do is raise the tool handle and possibly the rest.
On internal cylinders I find a standard square-section scraper is far superior, especially for getting into corners when turning boxes, because the bevels tend to ease the cut towards centre. The best box tool is a bedan with a slightly radiused edge used as a scraper.
Thank you. You are helping rethink my turning in several ways.
when sharpening scrapers I put it upside down so that the burr is lifted to the top.
Grinding as you see here produces a burr on top. HOw big a burr depends on how hard you push the tool against the grinding wheel. The less pressure the better the edge.
thank you for the video, I have a question for years. I dont understand the reason for honing with diamond only the upper face "to refresh" recommended from all, including Robert Sorby videos. If you honing only the upper face, the burr dissapears and I dont kwnow if the scraper is sharper again. Not convince me. Whats wrong with my appreciation. Thanks for your proverbial patience.
Honing the top of a scraper before regrinding removes the old burr. The advantage when sharpening on a CBN wheel (where there are no sparks) is that honing leaves a highlight on the end of the tool. The highlight vanishes when the edge is sharp.
@@RichardRaffanwoodturning yes I understand your video, before regrinding, but the maker's advice is "after use, honing only the top",... for the RS Hollowmaster cutters, for example, my question is if you agree that only the top refresh the edge.
@@tallerpinocho It's sensible to follow the manufacturers advice. The probably know what's best.
@@RichardRaffanwoodturning thanks !
@@tallerpinocho Here's my 2 penneth worth: The Sorby Hollowmaster has small, (admittedly) replaceable, HSS tips. If you take it to the grinder every time you wish to renew the edge, you're going to get through them very quickly and will constantly find yourself buying replacements. Also, it's worth noting that you don't need a burr on a scraper to make it cut. Look at the carbide tips you can get these days, they cut without a burr - some would argue a burr on HSS helps helps (personally, I'm not sure I agree), but the point is that by dressing the top edge of the tool with a diamond hone, you can get a good edge AND your tool will last much longer...
Your opinion on negative rake?
I think grinding a negative rake on a scraper is waste of good tool steel: I've never seen anything that can't be done with a single bevel scraper provided the angle between the surface being cut and the top of the tool is less than 90 degrees. There are plenty of situations where a single bevel square-end scraper is vastly superior to a negative rake - for instance turning an internal cylinder or corner. A negative rake for cutting is easily accomplished by adjusting the height of the tool rest and raiing the tool handle.
Thanks Richard!