On Thursday, October 1, 2015 at 8:22:33 PM UTC-7, John Doe wrote:
You want friction-cutting blades. The blade gets cherry-red, the workpiece
gets yellow, and the blade wins. Not good for a bandsaw, though,
the tires don't like heat. Usually seen in table saw, with lots of
precautions against sawdust accumulating in the spark path.
I've heard somewhere about arc cutting with a band saw. Alleged that
U-Haul did it in trailer fab. Use wood-cutting speed on a large band
saw, insulate the workpiece from the table with masonite, connect one
welder lead to the workpiece and one so that the blade is live. Blade
said to stay cool enough due to speed.
Never heard of it again, too chicken to try to do it with my antique
24" flat-belt drive saw.
Anybody actually do this?
The band might stay "cool enough", but arc erosion would be exactly the
same on the blade as it was on the material being cut (+-). So, if you
had (say) 1 square inch to cut, then you'd better have one square inch's
worth of blade to waste before it wears down too far to be able to clear
the guide bearings.
This is sort of along the lines of "friction heat cutting" with a
bandsaw. Yeah... right! You're going to keep the whole length of a band
at yellow-white heat continually... Really?
Well, maybe if your bandsaw can run at a couple-hundred feet per second!
On Sun, 04 Oct 2015 20:10:11 -0500, "Lloyd E. Sponenburgh"
The business about the band getting yellow hot is nonsense. The body
of a friction blade gets barely warm to the touch. 6000 FPM (100 FPS)
is fast enough for most uses, but some machines run up to 15000 FPM. I
used to have a 36" saw that ran around 6000 FPM, and it made quick
work of 1/4" stainless, was acceptable for 1/2" SS plate, and would
sever 3/4" bar stock in a pinch. My 16" DoAll tops out at 1500 FPM,
and will cut 1/8" SS, but it's a stretch.
On Mon, 5 Oct 2015 09:07:47 -0700 (PDT), " email@example.com"
It is, if the polarity is right and the relative melting points don't
It's possible to get "zero wear" on an EDM electrode (the electrode
wears, but the workpiece material is re-deposited on the electrode at
the same rate). It's tricky and not something to try with a bandsaw
blade. But there will be a difference in relative wear based on
several factors -- which I'd have to look up, but for which I don't
have the time.
I've stayed out of this thread because I saw no mention of workpiece
material hardness, only that it's "tool steel." Annealed tool steel is
commonly cut with a variety of HSS sawblades, typically the bimetal
type. Hardened tool steel can be cut with a carbide-toothed blade but
that requires a very rigid saw, hydraulic downfeed, and a bit of
Or, if your band saw can handle it you can friction saw it. They make,
or made, special friction sawing blades or for occasional use you can
just weld a blade the "other way" so the teeth point up. It takes more
than the usual pressure to get the cut started but once it starts to
cut feed pressure seems a bit less then conventional sawing.
I've cut 1/2" HSS tool bits by friction sawing with no problems.
Look up a company that makes bandsaw blades to order and ask them.
Bandsaw blade stock in many sizes and is available in both tungsten
carbide grit coated and diamond grit coated so one of those will likely
do. I know a chap that cuts up truck tyres with a TC grit coated blade
and it slices through the steel belting easily, didn't cost a great deal
to have it made either.
Buy M42 tipped blades and cool them before, during and after the cut.
Tool steel is often ground to size.
TC is good as well.
You don't say what you are cutting - just tool ?? steel ??
On 10/2/2015 3:00 PM, David Billington wrote:
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