Page:Practical Treatise on Milling and Milling Machines.djvu/168

162 Cutting a Large Spur Gear, Using Gear Gutting Attachment

This operation shows the use of the gear cutting attachment described in Chapter V. The gear being cut is too large to be accommodated by the spiral head centres without using raising blocks, and then the results are not as satisfactory as can be gained by using this attachment.

The gear is supported similarly to that on the opposite page. The advantage of a rim rest is illustrated, and it should also be noted that where the cut is as heavy as that shown, it is advisable to use the arm braces to give added stiffness to the cutter arbor. The table is fed from left to right, or so that the cut is against the rim rest.