The Science of Shear Scraping *LINK*

Excellent job

Re: The Science of Shear Scraping

robo hippy

I agree, good stuff...

robo hippy

I like the shape ground on the scraper.

I believe thats a Ray Key designed shear scraper

Re: I believe thats a Ray Key designed shear scrap *LINK*

john lucas

Many years ago I made a left and right hand shear scraper like he shows in the video. then I took a class with Ray Key and he had the spear point looking shear scraper so I built one of those. I finally got a John Jordan shear scraper and prefer it to my homemade ones that I gave away. John's holds a burr for a surprisingly long time. If you have the ceramic stone he uses to polish off the burr and raise a new burr it works really well. Here's my video on shear scraping showing John't tool.


https://www.youtube.com/watch?v=7oeiVQLeOd4

Re: I believe thats a Ray Key designed shear scrap

John K Jordan

John, I couldn't quite tell from the video - did you grind that big Henry Taylor scraper with a small negative rake? The grind on the flat scraper you used was pretty obvious.

I bought the John Jordan scraper some years ago but I have never used it! I will have to get it out the next time I do some face turning.

I've been wondering if a smooth radius ground on the lower edge of a shear scraper would be useful. As I mentioned earlier, I love using a small negative rake scraper I ground from a 3/8" Thompson rod and another I ground from one of his shallow detail gouges. The radius seems to make it "feel" just right and I think a little easier to control compared to another small scraper I made from flat Thompson stock. I like rotating the round rod scraper better than pivoting on the 90 deg edge to shear scrape with the rectangular one. These little scrapers leave end grain on a box lid almost as smooth as glass.

JKJ

Re: I believe thats a Ray Key designed shear scrap

john lucas

John I don't know if that big scraper had a negative rake when I did that video. It does now. I like the negative rake when using the tool flat to clean up tool marks or a knot that wants to fight you. In shear scraper mode I don't think the negative rake does anything other than the included angle is narrower which I kind of like for scrapers that are used as finess tools.

Re: Excellent job

robo hippy

I don't care for the straight edges on that type of scraper. One reason is that you can't use it inside a bowl. I prefer swept back on the left side scrapers for the outside. Use the nose for heavy roughing, and the wing for outside shear scraping. You drop the handle when using, and can not get on the high side and catch. I use a ) nose scraper for the insides. Drop the handle a bit and you can not get above the center and catch in shear scrape mode.

robo hippy

Re: Excellent job

john lucas

I like the straight edges for shear scraping the outside. It helps fair the curves.

Re: Excellent job

robo hippy

The swept back/inside scrapers have a long flat on the side. Hog with the nose, shear scrape with the wing.

robo hippy