A Better Gib Key Puller

Reader Contribution by Staff
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I noticed in a recent issue of GEM where someone was attempting to pull out a gib key with a tapered wedge. This method is not too efficient, as the friction between the flywheel and the head of the key is likely as much or more than the wedging effect. The pullers in the picture (see above and below) are way more efficient, and will pull the most stubborn keys easily. The small puller is for a 7/16-inch thick key, is 3/8-inch thick and is threaded 5/16-24, which is all the room behind the toe of the key. The larger puller is for 5/8-inch thick key, is 3/4-inch thick and tapped 1/2-20. In making a puller, a milling machine is a big help, but they can be made by hand with a little more work.

First determine the width of the key in question; this figure will be the width of the notch in the puller. Make this notch as deep as will reach the shaft. Note that the holes for the bolts are in line with the top of the key. This will keep the puller at the best location. Locate the bolt holes as close to the notch as possible, leaving enough room between them to permit a box-end wrench to fit. Round off and polish the ends of the pulling bolts enough so that if they burr a little, they can still be removed. Use a Grade 5 or Grade 8 bolt and grease the threads well. The small puller is chamfered a little to get the best possible fit on the key. Use a steel bar as big as will fit between the flywheel and the toe of the key for maximum strength. A good soaking of the key with a mix of half ATF and half acetone will go a long way to loosen up stubborn fits. Note that the center line of the cut in the puller body is in line with the center of the bolt holes. These pictures show a sprocket instead of a flywheel, but the operation is the same.

Harold R. Keller, Glouster, Ohio

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