Third Axis Levelling by Wendy Rowell

Step 1 - Level the Jig

Firstly ensure that the third axis jig is levelled by turning the levelling knob so the spirt level bubble on the jig is in the middle.

Step 2 - Level the Sight

Mount the sight on the jig and ensure that it is level with the jig in the horizontal plane. The metal mounting block will be level against the edge of the jig as shown in the circled area above. The scope on the sight should be level with the bubble on the jig. If not then use the 2nd axis levelling feature of your sight to level it off before proceeding.

Step 3 - Tilt the sight Upwards

We now need to simulate an uphill (or downhill shot) this will show if the sight is correctly levelled in the 3rd axis. When checking the bubble on the scope it should remain in the middle when tipped up, there should be no left or right movement of the bubble in the scope.

Any left or right movement of the bubble will indicate left or right error in your shots when aiming up or downhill. If the bubble is off then it will be necessary to move the scope unit in the third axis till it is level again.

Step 4 - Adjusting the Third Axis (1)

The adjustment of the third axis will depend upon the sight used. You will be moving the scope unit and not the sight itself. It is possible that your sight doesn't have third axis levelling. Most such as Sure-loc, Copper John and Axcel can be adjusted easily and the instructions should be followed. I use the Axcel 4500 which has independant removable third axis units allowing spare scopes to be pre-third axis levelled.

Step 5 - Adjusting the Third Axis (2)

Here you can see the third axis adjustment on the Axel. By unlocking a Hex Screw the scope unit can be easily moved within its third axis until level. The hex nut is tightened up and the sight moved back to the horizontal position. If the bubble remains in the middle in the horizontal and tilted up positions, then third axis levelling has been achieved.

Another way....

It is possible to use a small bow level and a tool such as the Sure-loc sight level to set third axis, however this is not as accurate as the first method because you cannot guarantee that the string will be level.

Step 1 is to level the bow in the vertical and horizontal plane by attaching the string level as seen above.

Now attach the Sure-loc sight level and check the bubbles are level in the horizontal plane. Make adjustments to 1st and 2nd axis to ensure the bubbles are matching.

Now either tilt the bow back in the bow vice or draw the bow back pointing down or up making sure to thread the elastic of the sight level through your D-Loop so it pulls straight. Check to make sure the bubbles on the scope and sight level match. If they do not then you have to adjust the bubble using the third axis adjustment of your sight.