Spade bits

buster · Post by **buster** » Fri Jan 09, 2009 11:04 am

I know this has probably been covered a million times, but I need some help. I understand the rounding of the bit, but where I'm stuck at is sharpening it. How do I do it ? Also, I noticed some talk of the bit has a tendancy to walk or chatter, could this be corrected by shortening the shank of the bit.

Post by **KurtHuhn** » Fri Jan 09, 2009 1:07 pm

The one thing I learned in my very stint working as a machinist is that the shorter your tool, the less chance it's going to wander or chatter. All of my spade bits have *maybe* a 2 inch shank.

ToddJohnson · Post by **ToddJohnson** » Fri Jan 09, 2009 2:00 pm

As for sharpening, you might find you have the most control with a rotary tool and the bit clamped in a vise. A smooth cylindrical stone grinding tool will put a nice edge on it. You can finish up with a whetstone or diamond hone if you have one. It's a must when you do this day-in and day-out, but some sandpaper on a metal, glass or very flat (MDF, Fiberboard) surface will also do the trick.

Todd

buster · Post by **buster** » Fri Jan 09, 2009 6:36 pm

Do you sharpen the side of the bit to look like a knife?

pennsyscot · Post by **pennsyscot** » Fri Jan 09, 2009 6:54 pm

I sharpen to a single bevel. The beveled edge should follow the flat side.

Frank · Post by **Frank** » Fri Jan 09, 2009 7:28 pm

buster wrote:Do you sharpen the side of the bit to look like a knife?

A knife grind angle is probably too extreme. You just need a couple or so degrees off 90 raked back. Make sense?

ToddJohnson · Post by **ToddJohnson** » Fri Jan 09, 2009 7:32 pm

buster wrote:Do you sharpen the side of the bit to look like a knife?

No. You simply relieve the trailing edge. In other words, look at the face of the bit and determine the edge that would actually be doing the cutting when the bit is spinning in a clockwise direction. If you have the bit laying on the table with the shank pointing up, it will be the "right" edge of the face you're looking at. Using that edge as the extreme outside profile of the bit, relieve the back side at about a twenty degree angle. Flip the bit over and do the same thing to the "right" side which, having flipped it over, will be opposite the one you just did. That sounds a little confusing, but just think about relieving the backside of the leading edge, or think about removing material from the trailing edge. All you're trying to do is create a single point of contact, and edge, and remove the material that would create friction.

Good luck,

Todd

Frank · Post by **Frank** » Fri Jan 09, 2009 8:14 pm

A picture is worth... yadda, yadda

buster · Post by **buster** » Fri Jan 09, 2009 9:24 pm

The picture is perfect. Thank you very much.

SimeonTurner · Post by **SimeonTurner** » Fri Jan 16, 2009 1:18 am

I picked up a tool at woodcraft that has made sharpeing my lathe tools and my chamber bits much easier. It's totally unnecessary if you have basically good skill with a standard grinder, but since I didn't have skill or confidence when I started pipemaking, I listened to the advice of some of the sales guys at woodcraft who were raving about a tool called the "jooltool".

http://www.jooltool.com/index.htm

I'm not even going to try to explain the tool; I'll let you look at the website and watch the little video to see how it works. Suffice to say, it is really easy to use, and it gives me the ability to sharpen my tools fast and with confidence (mostly because I can see what I'm doing so much better, and the metal doesn't heat up like it does on a grinder, so losing the temper in my lathe tools is less likely).

I usually finish my sharpening with a diamond hone and that's it!

Frank · Post by **Frank** » Fri Jan 16, 2009 3:20 am

SimeonTurner wrote:...a tool called the "jooltool".

Interesting gizmo, but $280 seems a bit steep for my pocket.

SimeonTurner · Post by **SimeonTurner** » Sat Jan 17, 2009 3:54 am

Frank wrote:
SimeonTurner wrote:...a tool called the "jooltool".
Interesting gizmo, but $280 seems a bit steep for my pocket.

Yeah, that's an outrageous price. I bought it at woodcraft for $80 bucks, I believe, plus the cost of a few extra sanding discs (they look like ninja stars).

No idea why they would be selling it for so much more online (or maybe why woodcraft was selling it so cheap! LOL)