||[Apr. 30th, 2003|10:24 pm]
Didn't quite feel like settling down after dinner today, so I profiled and surface prepped a viking sword, and while I had a 36 grit belt on the grinder I profiled 5 knives in a style from the Knives & Scabbards book. All told, this took about an hour. I like my grinders, they make the difficult easy, or at least quick.|
Word to any beginning knifemakers out there: power matters. On the Bader III with a 1.5 hp motor this would have taken hours, and I'd have probably changed belts midway. With the 4 hp grinder I can put much more pressure on the belt, and not only does it do the job much faster, but the extra horsepower means that the belts are useable longer.
Part of this is the nature of the belts themselves. With the modern ceramic belts (I was using Norton ceramic 36 grit) the grit is applied to the belt as a slurry, and as the grit wears away fresh edges of the grit are exposed. With a lower-horsepower motor, though, you can't put enough pressure on the belt to really wear away the abrasive material, and so the sharp edges dull, the belt gets loaded with gunk, and it stops grinding effectively. With the higher horsepower, you can put a lot of pressure on the work without bogging down the motor, and so you can keep using the belts until the abrasive is all gone. A fresh belt still cuts faster, but with 4hp, I can still get quite of life out of a well-worn belt.
For example, for the current belt I'm using, so far I've profiled and ground six tantos, one sword, five knives, and I still have a good amount of grit left.
Between the modern ceramic belts for the coarser grits and the Trizact belts for finer grits, belts are no longer something I need to purchase new for every project. Unnatural, I say, but still preferable to the endless changing of belts I had to do when I first started using larger grinders.
ah, science. got to love it.
at a folk thing last weekend, i was listening to a guy talk about using
various power shop tools, on curly maple, specifically to carve spoons,
and some of the cuts he considers dangerous (in general, esp with hardwoods).
what i found interesting was that some of the cuts he was describing would
probably be trivial with a different kind of tool, something more modern
perhaps, like a table water cutter, or laser even.
"dangerous" cuts? what kind of cut in wood would be dangerous? I spend a lot of energy making what I do in the workshop less dangerous, but cutting wood never struck me as one of the hazards. You keep your hand out of the path of the blade, right, and always use pushers or holders to keep the wood in place.
well, let's see if i can describe what he was describing without
visual aids :>
image a big wooden spoon, and you're holding the handle so that
the bowl portion is pointing straight down. you're going to be
moving the current botton edge of the spoon over some kind of
table-planer to smooth it out, and shape it.
my guess is that the grain at that point tents to resist being
cut, and probably bucks about, and if you're not careful, might
really either want to bind and grab or spit out violenty in
some direction (perhaps at your head?).
seems he does all the shaping this way - there's no "hand tooling"
as such. so, there's not a lot of pushsticks or holders, all free
hand, and probably a little twitchy.
one hopes he wears what amounts to what you wear; thick bib,
full face protection, gloves, and a handy deadman's off switch
Sounds like the kind of stuff I rig up a jig for. I do some freehand stuff, but if it's a choice between my art and my fingers, fingers win every time.
Come on, you've got 10 of them...