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sumu
15th January 2010, 05:10 AM
Hello,

Some time ago I found an interesting plane iron. It was made by Billnäs Bruk (http://billnas.fi/en/index.html) in Finland. So far, it is the only specimen of it's kind I've seen.

After some searching, I found a patent document (http://v3.espacenet.com/publicationDetails/biblio?CC=FI&NR=13022A&KC=A&FT=D&date=19300822&DB=EPODOC&locale=en_EP) from Esp@cenet archives. (In the case link does not work, the patent number is FI 13022, and the Date of publication is 22. Aug. 1930.)

There is basically three parts, and a nut and a bolt keeping parts together. The blade bed is machined (looks like it). The chipbreaker is punched from a steel sheet and then bent and grinded into shape. Both of these seem to be made of usual low carbon steel alloy.

The blade is really interesting. It is reversible, having two edges with bevels on the same side of the blade. This blade is clearly made of something else than carbon steel. My best guess is that it is some special high carbon tungsten-vanadium-chromium alloy of the era, one of those fancy early tool steels there was around during '30's. Might be even tool steel made by Poldi. Anyway, one could say it's a real tool-yuppie steel of it's age.

The chipbreaker has a grip to the blade bed in the upper end of the package. This system is ment to operate so that by loosening the screw and moving it, blade slides in between the chipbreaker and blade bed. That is how the distance between blade edge and chipbreaker edge is adjusted. Otherwise it works as a common wooden plane iron.

To be honest, it seems to be not that convenient or practical to use. I am truly wondering what went through the minds of Billnäs/Fiskars factorymen when they invested in the production of such a piece. For a plane iron, it has surely been quite complicated to manufacture, and that tool steel blade has been expensive stuff.

Perhaps it was something like that Fiskars wanted to see what's Billnäs good for, and therefore tested out all possible fields of markets and manufacturing methods for everyday tools. Could be there was a certain room for more peculiar inventions, too.

But as a piece of history of hand tools, I think it really has a rightful place there.

At least I would say there is even more delightful mousetraps around, too. Like Stanley 55. :)

Kippis,

Sumu

bsrlee
15th January 2010, 08:42 PM
It was probably meant for a tradesman working away from a shop, so he would have 2 sharp edges available without needing to set up his sharpening gear. Just loosen the bolt, turn the blade around & he's back in business.

I was reading Chris Schwarz latest book 'The Joiner & Cabinetmaker', where it is mentioned that in the early 1900's (and before) lots of tradesmen took their hand tools to a specialist to have them sharpened once a week, only giving them a quick touch up if needed the rest of the time.

sumu
15th January 2010, 09:47 PM
That's quite possible, too. At that time, Fiskars/Billnäs area was loaded with different kinds of craftsmen. There was a lot of industrial furniture and cabinetmaking, foundry patternmaking and other woodworking related business activities. It's possible that there was an exclusive target group segment for this kind of tool gear.

I have not thoroughly tested the blade yet (I need a suitable woodie body for it, preferrably a nice Fiskars/Billnäs factory made smoother body), but during the cleaning process I did a quick touch-up with fast cutting performance stones, and based on that single experiment it is at least 5 times tougher to sharpen than any carbon steel of the era I've had in my hands. There is obviously quite a high special carbide content involved in there, or at least the behaviour and feel implies so.

Kippis,

Samu

KimFinland
15th February 2011, 11:29 PM
Being very new in this field of research, I've been trying to investigate Finnish manufacturers of plane blades. I've got nothing else to add, than that the manufacturer Billnäs does mention the blade in question in trade catalogues published in 1936. I've yet to see one with my own eyes though, and having rummaged through different lots of old hand tools, I've never stumbled upon a plane iron other than those of Swedish or other origin. So my guesstimation is that however advanced the iron and chipbreaker was, it never sold all that much. Anyway, for those interested, here's a chunk of a illustrated trade catalogue that I found on the excellent digital collection maintained by the Helsinki University Library, Nationalbiblioteket - Digitala samlingar - Småtryck (http://digi.lib.helsinki.fi/pienpainate/secure/query.html?language=sv)


For those who can't read Swedish or Finnish, I suggest trying Google translate. Obviously you need to know what you're searching for, but if you do, they keep a pretty nice collection of old hand tool catalogues