What is a hole saw arbor?
What is a hole saw arbor?
Some hole saws are sold with attached arbors, while others are sold with detachable arbors. Some hole saws may be sold without any arbor and you may have to purchase one separately. Read our full guide on what is a hole saw arbor to increase your all round knowledge of hole saws and drilling.
Attached Arbors
Attached arbors are fixed (welded) to the hole saw blade and cannot be removed. The advantage of this is that you don’t need to dismantle the hole saw and the arbor every time you need to change saw size.
Because an attached arbor cannot be removed, it can be said to have an ‘integral shank’.
Integral Shank
A shank is the shaft that runs through the middle of the arbor and the part that the drill bit is attached to. An integral shank is when the shank piece is integral to the saw blade.
Put simply, this means that an arbor with an integral shank may only be suitable for use with a particular make, model or range of hole saws. One manufacturer’s arbors may not fit another manufacturer’s saw blades.
Detachable Arbors
Detachable arbors are not fixed to the hole saw but, instead, can be removed so that they may be used on a variety of different saw blades.
Although a detachable arbor can be removed, it may also have an integral shank.
Which is best?
Detachable arbors are not fixed to the hole saw but, instead, can be removed so that they may be used on a variety of different saw blades.
Although a detachable arbor can be removed, it may also have an integral shank.
Arbor Sizes
There are two main sizes of arbor: large and small.
Small arbors have a shank size of 1/3 inch (8.75mm) and are suitable to fit a 3/8 inch (9.5mm) chuck.
The smaller arbors are used with hole saws that have diameters between 14mm – 30mm (1/2 – 1 inch).
Large arbors have a shank size of 7/16 inch (11.1mm) and are suitable to fit a 1/2 inch (12.7mm) capacity chuck.
These larger arbors are used with hole saws that have diameters between 32mm – 210mm (1 – 8 inches).
An arbor’s hexagonal shank is measured by its diameter across the flats (AF). This is the distance between one flat face to another in a straight line.
1/4 inch arbor
It is worth noting here that hole saw arbors are chiefly for use in 3/8 inch and 1/2 inch drill chucks. Some manufacturers, however, are beginning to make arbors that will fit 1/4 inch chucks (typically found on impact drivers) though they are still uncommon.
Arbor Adaptor
Some hole saws and hole saw sets come with an arbor adaptor. An arbor adaptor is a simple threaded attachment that allows you to fit smaller sized hole saws to your large arbor.
The arbor adaptor fits over your drill bit and screws onto to the large arbor’s collar threads. You can then attach a smaller hole saw to the adaptor’s threads. The advantage of this is that you will not have to swap your arbor everytime you need to use a smaller hole saw.
