Replies

1. 
   NormKerr | May 17, 2002 01:46am | #1

   the only part I usually sharpen is the straight part.

   gosh, this is gonna be hard to describe without a picture...

   the screw part in the center is fine, leave it alone.

   the little tips on each end of the spade can get dull, but I haven't found any benefit to sharpening them.

   the straight part between them, however, is the "chisel" that does almost all the cutting and is REAL easy to sharpen:

   put the bit in a vise and use a fine file to re-sharpen the edge of that 'chisel' straight portion between the points. The angle you put on it isn't real important, just make it sharp again.

   I found this out after using up lots of spade bits rewiring a 100 yr old house (wood is hard as a rock after that much time). This little re-sharpen made them almost good as new and only takes a minute per bit.

   Now, if you have lots of holes to drill forget about the spade bits. Way too slow.

   Go out and get yourself a good auger bit and the holes cut almost as fast as you can go from stud to stud (needs a powerful drill and a strong arm preventing against kick-back though). After learning this I never went back to spade bits except for rare, onesy twosey hole jobs.

   happy drilling!

1. 
   DavidThomas | May 17, 2002 02:38am | #2

   I agree with Norm that sharpening spade bits is pretty easy, no really precision work. And that for more than a few holes, you want a self-feeding bit. MUCH faster and less effort on you.

   I first read the post as sharpening spades. Which I've only ever done when on a stand-by fire crew. We'd sharpen them so much that they needed duct tape over the edge for safe transport. Around the house, I ony take the dent off of a shovel blade.

   David Thomas   Overlooking Cook Inlet in Kenai, Alaska

1. 
   FrankB89 | May 17, 2002 04:45am | #3

   As far as I'm concerned, the best use of a spade bit is to grind them to a slight taper along the outside edges and use them for "easy-outs"  to remove pieces of broken pipe.  Otherwise, IMHO they're junk, hard on drill motors and make crappy holes.

   They are, however, easy to sharpen. Some people would bitch even if they were hung with a new rope.

1. 
   4Lorn1 | May 17, 2002 06:15am | #4

   I'll hang on to my collection of spade bits. Doing old work I frequently end up drilling into hidden concrete, cinder blocks, large deposits of sand plaster or cut nails.  These things can destroy a $30 auger or forsner bit very quickly. $20 will get you a decent set of 6 from Irwin. They are so cheap and being flat I can tote 2 or 3 sharp spares in a small sack.

   I sharpen them with a 10" bastard file. I hold them in a small vice and approximate the original angles. Anything close will work. Some people use a rat tail file and form an arc between the leading point and the outer edge. This creates a spur that smoothes the exit hole and cuts faster but doesn't last as long.

   I will still be reaching for an auger or forsner bit for more dimension or finish critical work. Both of these also cut slightly faster and with less pressure needed.

1. 
   FrankB89 | May 17, 2002 06:24am | #5

   Point well taken.... Some people would bitch even if they were hung with a new rope.

2. 
   MisterT | May 17, 2002 01:30pm | #6

   Chainsaw fileLayers

   Onions

   Have

   Layers,

   Carpenters

   Have

   Layers