This Hole Saw Extension is 7/16 Hex and 12 inch Long
And Comes with our New 7/16 (1/2") Style Quick Change
Push Pull Locking Pins Arbor, For Hole Saws from 1 1/4" to 10" Dia.
1/2" Arbors are Technically 7/16" but known as 1/2"
So if you have a 1/2 in Arbor they do fit 7/16 Extensions etc.
Comes with 2 Pilot Bits and Hex Key To Change Out.
So You Don't need to go looking for One.
There is an Option to Purchase Without an Arbor
Also a 22" Long Extension
This Arbor fits a Regular 1/2 inch Drill Chuck
Adaptors / Arbors / Mandrels
Whether you call the Adaptor that holds the hole saw in the drill an arbor a mandrel or an adaptor, there are only 2 thread sizes which coincides with the 2 sizes of threads in All Hole Saws one has 1/2 inch Thread and one has 5/8 inch Thread.
Then you have a choice of whether you need a Hexagonal Ended Arbor which fits a regular 1/2 inch Drill Chuck or an SDS Plus Arbor which is the one with Grooves on it that Slides and locks into an SDS Plus Drill instead of a Chuck.
Hole Saws Over 1 1/4 inch Need this Bigger Style Threaded Arbor and must have the 2 Locking Pins and a 5/8 inch Thread, these Arbors fit all hole saws up to about 10 inches Diameter.
(Not to be confused with Diamond Core Bit Adaptors which although they have a 5/8 size thread its different so they will only fit Core Bits)
Thread the Hole Saw onto The Arbor as far as possible then unscrew until the locking pins can be fully inserted into the 2 holes you might get lucky and not have to unscrew too far but they MUST be inserted.
We have started selling and supplying our Quick Change Arbor / Quick Release Arbor with spring loaded pins so it is a push pull into the holes instead of a screw into the holes, these do not loosen like the older screw in style.
If the locking pins are not engaged in the back of the hole saw it puts huge amounts of pressure onto the screw threads and will destroy them, especially when using carbide hole saws so it is extremely important to use them correctly.
The Adaptor with a 1/2 inch Thread is for all Hole Saws up to and including 1 1/8 inch Diameter. These smaller diameter Hole Saws used with these adaptors do not put a huge amount of torque / pressure on the threads of each other so they do not need locking pins.
The Pilot Bit used with Carbide Grit Hole saws and a Hammer Drill for Masonry should be TCT (Tungsten Carbide Tip) Which is the Drill Bits with a Piece of Tungsten Carbide Welded into the tip - my wife calls it the little house shaped piece.
If you are Drilling through softer material like Drywall Fiberglass Hardie Board Etc. use the HSS Type Pilot ( High Speed Steel) This is the same design Pilot Drill as the TCT but without the House Shaped Piece of Carbide welded in the tip, HSS is the type of drill usually used for drilling steel and wood. Although Carbide Grit Hole Saws can cut Hardwood they should not be used on soft non abrasive materials like softwoods as that will just clog the grit and not work very well. They are also not the choice for cutting metal or steel. I have had some success with Cast Iron etc. but not soft metals.
