Hole Saws and Arbors
Contents
Consumable Hole Saws
Facing the hole Saw
The paint must be removed from the back of the hole saw so that it meets the arbor as square as possible.
A light lapping shows that this saw would have been prone to a slight wobble.
Sharpenable Hole Saws
Arbors
Most hole saw manufacturers provide some way of holding the saw. This is usually done in a less than precise way.
The natrual solution is to take some precision shaft and thread the end for what ever hole saw size you need. This has the advantage of being able to make an extended arbor.
Here is one that I made years ago.
For improved precision and more ridgid foundation to your saws, use an arbor For threaded drill chucks. These are available from several suppliers, but one of the cheapest I found was Victor Machinery Exchange, Inc.
VME threaded drill chuck arbor:
DCA-1/2-1220 1/2" Straight to 1/2"-20 Drill Chuck Arbor $5.90
The BIG PROBLEM! Hole Saws are threaded for 5/8"-18 not 5/8"-16 as is commonly available for drills.
Then we look at threaded shanks for mounting boring bar heads.
Index of 5/8-18 Threaded Shanks by Everede available from MSC Shank Mfr's P/N MSC P/N Price 1/2" Straight Shank SHK-5818-500 04103453 $45.75 5/8" Straight Shank SHK-5818-625 04103461 $45.75 3/4" Straight Shank SHK-5818-750 04103479 $45.75 1" Straight Shank SHK-5818-1000 04103487 $45.75 R8 Shank SHK-5818-R8 04103495 $45.75
http://www.sevcal.com/shanks.htm
Also, for an extended R8 mounting a 5/8-18 thread saw, you can cut an R8 blank from Allied Machine. At $156 for the smallest model, this is not an option at this point. Plus, you would need a 24mm collet to hold the R8 in a lathe.
If you mitre on a lathe and need a 5C chuck arbor, a 5C Plug Chuck with 1-3/4" Extended Nose Length and no pilot hole should be ordered. It can be threaded for what ever saw you need. Available from Hardinge, P/N 10150000000000, $30.25.
Personally, I prefer to use either a R8 or 5C tool whenever I can. They are the most ridged and accurate way of mounting a tool.
Truing Hole Saws
Hole saws may not end up perfectly round. A frame builder may have to true the saw by spinning it on a lathe and cutting material from behind the tips that extend past the cut area.
