Ray Stubbs wrote on Jun 10^th, 2019 at 7:00am:


Yes,
The N in NRS is for Negative  angle. This means that the only difference is how (at what angle) the cutting edge is presented to the wood. If you change the angle of the handle you do indeed wind up with the same thing.

The diagram usually helps people see what they can't visualize

Like most things, it's a trade off.
You can't remove as much material as quickly as with a standard scraper but a NRS is  much more forgiving and requires much less effort to operate, from you and your lathe.

This subject is going on in another thread as well, I will try to answer what I can.

Mike Nathal wrote on Jun 10^th, 2019 at 5:24pm:


One point I will disagree with Mr Batty on, is that you need a burr on a NRS, you do not.
This is a provable fact not simply my opinion. The other thing is that Mr Batty has decided what angles should be used to be considered to be classified as a positive and negative rake scraper.
In the diagram I posted the included angle of the standard scraper would be too great to be considered a NRS by Mr Batty, even though it is clearly cutting in a negative rake angle.

People have been using everything from a piece stone, to a broken piece of glass to scrape wood for thousands of years without a burr.
Look at a scraping plane which can be used with or without a burr or the scrapers recently discussed Multimedia File Viewing and Clickable Links are available for Registered Members only!!  You need to or . These do not have a burr by design and are used at a negative rake angle. As mentioned in the other thread there are NRS inserts for replaceable tip tools like Easy Wood Tools, these are carbide and do not have a burr.

I don't intend to start an argument but the physics (geometry) of Standard (positive rake) and Negative rake scrapers is clearly visible in the diagram I posted.

Mike Nathal wrote on Jun 10^th, 2019 at 5:24pm:


This is what I have been trying to convey.
A NRS is by design less aggressive, which in turn lends itself to be easier to control.

I want to be clear, a NRS can have a burr, if there is a burr, it is usually just an artifact created by the grinding/sharpening process. Not a work hardened or burnished burr like you would find on a standard scraper.

Don Stephan wrote on Jun 10^th, 2019 at 7:13pm:


This isn't entirely accurate
Here is a section on scrapers cut from Multimedia File Viewing and Clickable Links are available for Registered Members only!!  You need to or I feel this explains the topic well

Pointing a Scraper Downward


It is often suggested that a sure-fire way to avoid the unpleasantness of an aggressive scraper is to raise the handle so the tool points downward at a significant angle. This supposedly puts the cutting edge in trail and makes the tool easier to control.


However, . . . if the burr has a significant curl, pointing the tool downward will have just the opposite effect. The burr will be aimed directly into the wood which will make the problem worse. A heavy cut is likely to follow.


A secondary effect is that a force will be exerted on the tool that tends to pull it across the tool rest toward the workpiece. This is the self-feeding tendency. I think the chances of it causing a serious mishap are small, but it is a bit unsettling to feel.

Here is a video that may answer some of the questions you have. I sure hope so.

Multimedia File Viewing and Clickable Links are available for Registered Members only!!  You need to or

Ed Weber wrote on Jun 11^th, 2019 at 12:06pm:


Like on a card scraper?