Arno Burnisher

[Tony Zaffuto]

I'm not familiar with the Two Cherries burnisher, however years ago I bought a burnisher made by one of the British makers, and the rod was bright & shiny, however that was due to chrome plating! After a few uses, it began to peel. Carbide is by far the best, but I've also had good results with polishing HSS dowels.

[Richard Jones]

Not chrome plated, and sparks like HSS. I certainly agree that harder seems like it would be better, assuming good scraper material.

[Phil Mueller]

John, I have little experience with curved scrapers and would appreciate any feedback on the Arno. Is there also a need for a burr on an inside curve...or is that essentially a true “scraper”? I have to say my shavings are still not perfect, but far better than before. Like any tool, it just takes a committment to spend a few hours and try, repeat, try, repeat. I’m getting there! I also quickly tried the cylindar side vs the triangular side on one straight scraper last night. Might be technique, etc., but the triangular side might have done a slightly better burr. But I’m still working with so many variables with my technique, that it isn’t a good indication. I’ll be very interested in what you think.

Tony, I think that was a major problem with my previous burnisher...I think it is plated. The surface isn’t any where near smooth after a few uses and was getting me nowhere.

[Derek Cohen]

Add to the cabinet scraper armoury a scraper made from thick O1 steel. I made the following out of the end of a 3/16" thick O1 plane blade. It must be flat (as above).

Take it to the grinder (I use a 180 grit CBN wheel for this) and create a hollow around the edge.








And you are done. This is a fantastic tool for removing a large amount of waste. Think of it as a jack plane. And yet it can be good enough to leave a finished surface.





Regards from Perth

Derek

[John K Jordan]

Add to the cabinet scraper armoury a scraper made from thick O1 steel. I made the following out of the end of a 3/16" thick O1 plane blade. It must be flat (as above).

Take it to the grinder (I use a 180 grit CBN wheel for this) and create a hollow around the edge.


Derek

For those who can't make their own, buy them from Stewart McDonald:
https://www.stewmac.com/Luthier_Tool...e_Scraper.html

They aren't cheap but they are well made. I like the dished sides which make them easier to hold. 1/8" thick.

SCRAPERS_StewMac_IMG_20171019_081858_098.jpg scrapers_platter2_IMG_20171111_161724_603.jpg

I bought O1 steel and plan to make some different shapes with the plasma cutter. Maybe this summer...

JKJ

[mike holden]

Congratulations Derek! you have recreated a patternmakers scraper. Primary use that I had for them was to remove parting lines on fiberglass splashes. Make the model in mahogany ply, apply dimensional thickness wax to the surface to account for metal thickness (models and prints are drawn/built to inside of metal), then make a fiberglass copy of the outside of metal. Due to having to use clay to fill in the seams between sheets of wax, there were parting lines on the fiberglass. A scraper with a hollow ground edge laid flat on the surface would remove the parting lines quite nicely.
BTW mahogany ply had 1/8 thick plies with the grain all running the same way, made for a very dimensionally stable block of wood.

[John K Jordan]

Phil,

I got the Arno Burnisher last week and gave it a quick test today. It's well made and the handle is comfortable. There was some gunk on the carbide (looked something like dried oil or lacquer) but it cleaned off OK. The leather case is nice.

I tried my other smaller round carbide rod burnisher and both the cylindrical and triangular sides of the Arno. I applied them to three similar edges of a freshly honed curved hand cabinet-type hand scraper. I tried to use the same force for all three. I tested each edge on a piece of madrone right off the bandsaw.

As expected, the triangular side (having a small radius) took much less force to raise a cutting burr. The burr was more aggressive than the two cylindrical carbide burnishers. I didn't look at the burr yet with the microscope but it felt rougher. If so, it wouldn't be a problem since I follow the curved scrapers with fine sanding.

My smaller carbide rod burnisher turned a burr that felt smoother and was almost as aggressive as the triangular one. The round side of the Arno raised the smallest burr with the same force, as expected since the diameter is larger. It felt considerably smoother than the burr from the triangular side.

I liked the use and scraping edge from the triangular-burnished edge but wonder if it will hold up as well if it is not as smooth as it seemed. It may work differently if angled a little (rotated around the handle axis). When I get time I'll do more careful testing and compare the edges under the microscope.

JKJ

[Phil Mueller]

Thanks, John, appreciate the feedback. I was thinking about you as I was taking some nice shavings on a piece of burl, wondering if you had received it. I’ll be interested in any further observations and comparisons to your smaller round burnisher. I’ve been eyeing one, but kind of waiting to hear your thoughts.