Sharpening woodturning scrapers

[graduate_owner]

Hi all,
I know scrapers cut by creating a burr, and you sharpen them by raising the burr on a grinding wheel. Also I remember seeing a sharpening device marketed by Trend which involved pushing the tool against a hardened steel pin, a bit like raising a burr on a cabinet scraper with a burnisher.
So if you can raise a burr by pushing the edge over, is it possible to raise a burr by tapping the edge over slightly with a hammer? Now this may be a really stupid idea, but if I was to hold the scraper in a vice and tap the end with a hammer, would I create a useable burr, or just create a scraper that needs re- grinding!!

Any comments? Anyone tried this?

K

 

[CHJ]

If you try that with HSS you will just as likely shatter the edge (at the same time as you score your hammer).

To raise a Burr you need to force a flow of material without cracking it.
Easy to do on carbon steel tools but not so easy with some HSS variants and needs doing against something like a Cobalt pin, personally having played with it for some time I must have come to the conclusion that I never found it any advantage that's worth the effort over a wheel raised burr because I can't remember the last time the tooling came out. About once a year I have a cut that maybe would have been better tackled with such and it's easier to stop the lathe and use a cabinet scraper.

Maybe it's also because I have now developed more confidence and will attempt shear scraping with a sharp bowl gouge as a norm now.

My excursion into Formed Edge Burrs was in early 2011.

 

[Dalboy]

When I use a scraper unless the edge is bad I don't put it on the grinder. So between cuts I use a diamond card to run over the top and a few circular motions around the taper this I find is enough for the times I use it and with less material removal than a grinder

 

[Paul Hannaby]

I also often sharpen my scrapers with a flat hone. It doesn't produce much of a burr but enough to work effectively.

 

[woodfarmer]

On older steels "boning" would produce the burr you seek. As has been said though much more difficult on HSS.

As an aside, I sometimes use my skew chisel as a negative rake scraper, when sharp cleans really well and is particularly good for working convex surfaces. Hope to convert a big genuine scraper to negative rake, I know using the skew is a bit hard on the thin section of the skew.

 

[graduate_owner]

Ah, so it's called boning.
I can't see though how this is much different to creating a burr using the Trend jig.

K

 

[woodfarmer]

Ah, so it's called boning.
I can't see though how this is much different to creating a burr using the Trend jig.

K

I was taught this expression by an engineer who serviced tools for the tanning industry. Scrapers (mechanical) are used to clean the hides (inside side)

 

[JimB]

I was taught this expression by an engineer who serviced tools for the tanning industry. Scrapers (mechanical) are used to clean the hides (inside side)[/quote]
That's interesting. Back in the old days, (my new days) army boots needing boning to get a gloss on them. We used the back of a hot spoon or fork but I assumed at one time they must have used a piece of bone. When you think about it 'boning up' on a subject does mean polishing it metaphorically.