Introduction: Broaching

a quick easy way to get a keyway on inside diameters

materials needed:

a broach set
an arbor press

(both available at TechShop)

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Step 1:

using the broach set, fit the correct insert into your ID ( this example uses a .375 diameter insert)

grab the broach that goes with the size key you want and get the shim ready.  (this example uses a 1/8 broach)

Step 2:

using the arbor press "push" the broach through the insert into your part.  this will leave only a slight key way in your part.

Step 3:

place the shim into the slot of your insert and run the broach through again.  this will give you the depth you need for your key way.

Step 4:

and there you go - a key way on the id of your part

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    7 years ago on Introduction

    Cute arbor press. Dedicated broaching machines are a tad bigger than that. I ran one that stood over 20 feet tall. Thing was a beast! It could rip a dovetail an inch deep, and as wide in one pass. Trust me when I say you don't want to operate a broaching machine. It can hurt you more ways than you've fingers to count them.

    It was hands down the very worst job in the shop, running the broach.

    The oil nozzle on our broach was twice the diameter of your insert. Imagine all that oil pumping out and spraying off the cutting teeth into yours. It was about the size of a garden hose. We didn't use water based coolant in the broach either, stuff was more like motor oil. Just lovely.