How to use a wiggler to find the centre of a hole in a part

Shop for Centre and Edge Finding Sets

Step 1 – Insert probe

Insert the probe into the body of the wiggler.

Step 2 – Mount wiggler

Mount the wiggler into the chuck or collet of your milling machine or drill press.

Step 3 – Secure workpiece

Secure the workpiece in a vice or base-plate underneath the spindle of the machine.

Step 4 – Start machine

Start the mill, setting your machine to run at 1000RPM. The ball probe will start to centre itself.

Move the table so that the end of the ball probe finds the outside edge of the part.

As the wiggler moves closer to the part, its wiggling motion will start to subside until the tool appears almost still.

Step 5 – Move the table

Continue to move the table towards the tool until the wiggler breaks away and the probe kicks away from the body.

It will do this when it reaches the part.

Step 6 – Zero x axis

As soon as the wiggler breaks away, zero the x axis on the digital read out (DRO).

Step 7 – Traverse the table in x direction

Traverse the table in the x direction so that the ball probe moves closer to the opposite edge of the part.

Step 8 – Half value on DRO

To find the centre of the part on the x axis, half the value indicated on the DRO.

In this case, the value shown is 9692, so 9692 ÷ 2 =  4846.

Step 9 – Move table until DRO reads zero

Move the table until the x axis reading on the DRO is zero.

The spindle of the machine will now be directly above the centre of the hole in the x direction.