Negative Rake Scraping by Stuart Batty the Pioneer of this Amazing Technique - Part 1 (4k)

Part 1 of our Negative Rake Scraping (NRS) Series, showing how effective this technique is at refining and perfecting shapes, while creating an exceptional surface finish. 0:00 - History & Development 04:48 - NRS on End Grain 15:37 - NRS on Mixed/Alternating Grain 20:55 - NRS on an End Grain Box 40:54 - NRS on a Sphere Why Stuart Batty Developed Negative Rake Scraping: In 1983, Stu ran a sawmill in the UK, turning bowls from every wood species they sold. When it came to turning Western Australian Goldfield Burls, a very dense eucalyptus species with highly figured grain, the gouge would always tear the grain on the wide flat surface of the winged bowl, no matter how it was sharpened. Note: This species is far too dense for safe use with Conventional Scrapers. Stu decided to try an old ivory-turning technique using a double-bevel chisel that was honed to create a burr free sharp edge. However, unlike all other woodturners at this time, Stu had stopped honing the edge & used his tools directly from the grinder. This meant his double bevel chisels naturally had a burr left on the edge. So when used on the wing of the bowl it created a Smooth, Flawless Finish, but only for a few seconds before it wore down & the tool started to tear the grain. This led Stu to deliberately create & maintain a burr & use wider blades made of superior edge holding steels like 10V & 15V. This enable a much longer working time to refine final shapes and created an exceptional surface finish that only needed fine grit sandpaper to complete. What is Negative Rake Scraping? (NRS) NRS is a non-aggressive shaping technique that uses a chisel with two bevel angles. The key feature is the trailing negative angle created by the top bevel with a burr facing upward along the cutting edge. How It Works • The burr does the shaping & creates the final finish • Once the burr is worn off, the technique loses effectiveness, especially for the final surface finish • A dull tool can still be used for rough shaping, but resharpening is required for a smooth final-finished surface & no torn grain Important Note: A properly formed burr is essential for NRS to work effectively & for the final surface finish. The burr must be created directly from a wheel or belt grinder. Using a burnisher or ticketer creates a curled edge, & is a more difficult approach, requiring exponentially more time to create a burr and showing no benefit in the finish. Why NRS is Different from Conventional Scraping Conventional Scraping has been used for centuries, always executed with a single-bevel and included angles of 50°–80°. These can be used with or without a burr, but they are aggressive & self-feed, especially on end grain & dense woods, & require careful control to avoid catching & grain tear-out. Just pointing a Convention Scraper downhill does not make it Negative Rake. Negative Rake Scraping uses a double-bevel with included angles of 40°–70° & always requires a burr to function properly. Unlike conventional scraping, NRS is a Neutral Technique—it neither pulls the wood in nor pushes the wood away when being used correctly, making it far more controllable, even on dense end grain surfaces. Why Negative Rake Scraping So Effective 1. It’s Not Actually Scraping—It’s Form of Hard Abrasion Despite the name, NRS isn’t traditional scraping. The burr acts like grinding wheel, removing wood fibers &, unlike sandpaper, it does so without flexing. This makes it the most effective & efficient technique for refining final shape and creating an exceptional surface finish. 2. Superior Control & Wider Blades • Conventional Scraping (CS): Requires the highest overhang ratio of all woodturning tools at 7:1 and can be highly aggressive & self-feeding on end grain • Gouges & Chisels: Require a 5:1 overhang ratio for full ergonomic control, especially with performing heavier volume cuts • Negative Rake Scraping (NRS): Requires the overhang ratio of 3:1—the lowest of all woodturning tools this is because it’s a neutral & easy to control technique • Unlike Conventional Scraping, NRS doesn’t become more aggressive on denser woods and works well on all grain types, densities and direction • No limit to NRS Blade Width – this is why we manufacture the widest NRS & biggest range of shapes, enabling turners to match the work they create 3. Efficiency and Exceptional Surface Finish with NRS • Significantly reduces sanding time & sanding materials • Enables sanding to start with a finer grit • Enables exceptional fine detail, thin work, crisp edges all without tear-out • Works well on softwood but is best on medium to dense woods (not good for spalted or rotten wood) Stuart Batty a 3rd-Generation Master Production Woodturner who Pioneered: • 40/40 Bowl Gouge • Bottom Bowl Gouge • Vortex Tool • True Push Cut • Negative Rake Scraping #woodturning #turning #woodturningtools #stuartbattytools #negativerakescraping