Things they don't tell you about hole saw arbors #23

[David]

Having bought a hole saw and arbor from Screwfix and put them together in what I think is the correct configuration I was frustrated by the fact that the pilot drill was barely longer than the depth of the hole saw which made it very difficult to align it with the mark for the centre of the hole.

I located a screw on the side of the arbor and removed the drill to check the size and look for a longer one.

Turns out that the drill had 3 little notches in the shaft to allow pre- setting different drill lengths.

Who knew?

Still a bit of a fiddle to make sure the grub screw located properly in one of the three notches, but at least a variable length pilot drill.

Cheers

Dave R

[John Rumm]

Not all of them have the notches... you can also substitute the supplied drill for a longer one if it helps. (I also realised you can stick a long drill in it, and leave a bit poking out of the back, so you can grab it with the chuck. Handy when the shank on the arbour is 12mm and you want to use it in a drill with a 10mm chuck).

[Tim Lamb]

I want a hole saw manufacturer to design a tool that doesn't require considerable effort to extract the waste!

How about putting holes in the top so you could use a punch rather than fiddling around with various screwdrivers.

[Steve Walker]

Don't try and drill on the mark with it. Use a separate drill or use the arbor and pilot drill without the hole saw first - then you've got a positive location for the pilot to locate in.

SteveW

[billyorange007]

Go to 1.16 to see tyhe feature you desire. Works good. We have one

[billyorange007]

CMT sold by Scott and Sergeant

[Tricky Dicky]

I recently had to holesaw some awkwardly placed holes in trunking, like Steve I drilled all the pilot holes with a normal 6mm drill first then all the pilot drill had to do was locate in the pre-drilled hole. Alternatively in material where the pilot drill may wander or drill an off centre hole, make a template, secure it in position and drill without the pilot drill. Worked for me when I had to match the entry points on a CU with holes in the trunking. Also worked for me when core drilling for some conduit and I did not have a long enough pilot drill.

Richard

[Tim Lamb]

In message [e-mail], Tricky Dicky [e-mail] writes

I've done this using core drills too small for a guide drill.

[Tim Lamb]

Now why didn't you tell me that before I bought the set I use:-)

[ARW]

Worked for me when I had to match the entry points on a CU with holes in the trunking.

Was it you that came down in conduit from trunking up at ceiling height to the knockouts?

[Tricky Dicky]

Yes Adam, I used conduit couplers with brass bushes to connect to trunking from the CU.

Richard

[ARW]

I don't forget everything I read then:-)