Making Bearing Shims

| May/June 1996

  • Shim to be Drilled
    1/4 inch steel plate. Shim to be drilled, placed between the two pieces of iron-bolted tight together. Then drill the hole in the shim.
    Drawing by John M. Edgerton
  • bearing shim
    Main bearing shim for a 6 HP IHC Model M.
    Drawing by John M. Edgerton

  • Shim to be Drilled
  • bearing shim

I don't know if this tool is worth writing about but it sure worked for me!

I'm sure other restorers have had to make bearing shims one time or another. Cutting the outline of the shim is no problem, but how do you make the hole through the thin shim stock? I don't have any punches that will work on metal, so I came up with this idea.

I took two pieces of steel bar 5- by 1-1/2- by 1/4-inch thick, clamped them together and bored two 17/64 inch holes 2 inches apart and about 3/8 inch in from one edge. These two holes may vary with the shape of the shims you're making.

In the middle of the 5 inches (at 2-1/2 inches) I bored a 21/32 inch hole, which is the size of my bearing bolt, through both pieces. By drawing a circle where I want the hole bored in the new shim, I can now line the hole up with the 21/32 inch hole, clamp the two pieces together using two 1/4 inch bolts in the 17/64 inch holes. Put this in your drill vise and use the 21/32 inch drill to  drill a hole in your shim. Of course not everyone has the same size bearing bolts, so the 21/32 inch will vary. My bolts are 5/8 inch, but I like to drill the shims a little bit larger.


Gas Engine Magazine A_M 16Gas Engine Magazine is your best source for tractor and stationary gas engine information.  Subscribe and connect with more than 23,000 other gas engine collectors and build your knowledge, share your passion and search for parts, in the publication written by and for gas engine enthusiasts! Gas Engine Magazine brings you: restoration stories, company histories, and technical advice. Plus our Flywheel Forum column helps answer your engine inquiries!

Be sure to take advantage of the Square Deal Subscription Program.

  • No Missed Issues.

  • No Renewal Notices.

  • No Additional Cost.

The Square Deal Subscription Program is designed as a paperless transaction with automatic renewals at a preferred low rate.   With advanced electronic notification, a 100% satisfaction guarantee and an easy opt-out plan, the Square Deal Subscription Program is the best value, risk free, eco-friendliest way to subscribe.

Facebook YouTube