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View Full Version : Is it OK to use a stainless screwdriver as burnisher?



Osvaldo Cristo
12-24-2016, 5:23 PM
I am buying a couple of Bahco scrappers - they will my first ones... I am considering to purchase a stainless steel PH2 to work with my very rare stainless screws and to use the same screwdriver as burnisher when sharpening the scrappers.


It sounds logical to me as stainless steel is very hard but perhaps I am missing something.


Your experience and advice is very welcome.


Thanks in advance for your input.

george wilson
12-24-2016, 5:38 PM
STainless steel need not be very hard at all. It depends upon which stainless the tool is made from,and how it was hardened and tempered. 440 C is one stainless that can get quite hard. 440A on the other hand,contains much less carbon. Those cheap Chinese Marbles repro ,Rough Rider,and other Chinese pocket knives(and a LOT more,not necessarily Chinese) are made of 440A. They are not very hard.

When I was teaching shop in a school with only a little money,I was using a NON STAINLESS Proto brand screwdriver quite well as a screwdriver,to put a nice burr on scrapers I taught the class to make from large lumber mill bandsaw blades. Likely made from L6 steel,not terribly hard,since bandsaw blades need to be flexible. This was in the 60's,so I don't know if Proto brand screwdrivers are still of the same quality. Or,even still made in USA,for that matter.

Mel Fulks
12-24-2016, 5:39 PM
Can't hurt to try it ,but I don't think it will work. Even some of the things sold as burnishers are too soft. A 1/4 inch solid carbide laminate cutter router bit makes a good burnisher when mounted on a handle. I use the Goop type glue to hold the bit in a shallow cut in center of a wood handle. Sometimes friends will just give you bits too dull for laminate .

george wilson
12-24-2016, 5:57 PM
You can buy round rods of HSS from places like Manhattan Supply co. These rods are intended to be broken off and ground into cutters for boring bars. HSS is,however,not really as hard as some other steels. Samples I tested were about 63 RC. Even Chinese HSS,which tends to be harder(and more brittle) than USA made cutters,were not much harder. W1 reaches right at 67 RC when hardened,and needs to be drawn back a bit,as it is brittle as glass! But can still be over 63 RC even after tempering. Depends upon how hot you get it when tempering. You can also buy rods of solid carbide from the same source,and it IS as hard a burnisher could ever be,and then some. Up in the 70's of Rockwell hardness. It is brittle,but burnishers don't really need to be long. 1" will really do,with the rest of the rod set into a wooden handle.

Glen Canaday
12-25-2016, 6:51 AM
The screwdrivers I tested were too soft. The scraper cut the screwdriver rather than accept a burnishing from it. Modern screwdrivers just don't have it going on in the hardness department.

I bought a carbide rod and inserted it into a wooden dowel to use as a handle. Works great and there isn't a scraper made that will hurt it. The rod cost maybe $6-$12 from a carbide supplier.

Osvaldo Cristo
12-25-2016, 7:26 AM
Thanks guys for your fast answers even for my first post! I really appreciate.

The carbide idea looks me promising. Anyway I will try to use a Wera PH2 stainless steel screwdriver as I was looking for one for my occasional stainless screws... at around US 10 it is cheaper than virtually all burnisher offers I found... and I like the idea of "multi purpose tools"... :-)

Have all of you a great Christmas!

Rob Luter
12-25-2016, 7:31 AM
I'll echo what the others are saying...screwdrivers will likely be too soft. An inexpensive solution is a hardened and ground dowel pin used in the machine and tool industry. One company that makes them in Holo-Krome. They're readily available from an industrial supply store that carries nuts and bolts and the like. Here's one source in the US (https://www.fastenal.com/products/details/1126753;jsessionid=I89cninbkvYwK1k3PHBXvGv1.385364 38-9c19-3947-9017-bf77ad0514fd?r=~|categoryl1:%22600000%20Fasteners% 22|~%20~|categoryl2:%22600108%20Pins%22|~%20~|cate goryl3:%22600111%20Dowel%20Pins%22|~). You may have someone similar in Brazil.

Bill White
12-26-2016, 3:07 PM
Plain old drill rod?
No way I'm gonna try to burnish with a screw driver.
Then again, most of my scrapers (SCRAPPERS?) are of different hardness. Why? Beats me!
Bill