No. 1 Taper Pin: What is it?

[Colin Rush]

Here is a question for the machine tool and old iron types.

My 1923 IHC Model M motor uses an ignitor. The factory parts book describes it as a "Number 1 Taper Pin."

So, my question is: what is a Number 1 pin, and how do I learn the dimensions and/or specifications of this piece?

Over the weekend, I looked in SAE handbooks going back to the 1920s, and found nothing (I found everything else, so I bought two), so I suspect it is even older than that, and possibly more of a hardware item that was readily available in the late 1800s and early 1900s.

I know these are available new from the vendors, but if it was available then, I wonder why it is not available now. Or maybe it is, and the terminology has changed since then.

If anyone can help out here, please, jump right in.

[LeRoy IHC]

No. 1 taper pins are in the McMaster-Carr catalog. You should be able to go online to their website and look up taper pins. They have pins from No. O up to No.10 Their phone number is 732-329-3200 or www.mcmaster.com

Hope this helps

[Greg Downard]

They used these a lot on old farm equipment for shear pins. A #1 I beleive is about 11/64" on large end and depending on the length as to the smaller size on the other end. Usually were made from soft steel so they could sheer off. Tapered so they could be tapped (wedged) in and not fall out. Tractor Supply, ACO, Ace hardware still carry them in those little drawers of odd bolts. Grainger, McMasters carry a larger supply. I'm not sure but think you can get them hardened and stainless now too.

[Jonathan Widelo]

Colin,
I was able to get a taper pin for my Fairbanks Morse Early and Later Tripper device for my 3 HP Bosch Equipped Engine at a local Hardware store.
So a Larger hardware store might have them in stock.
~ Jonathan

[Gasengn]

Where can you get a drill or reamer to make tapered pin holes?

[Colin Rush]

For a second, I thought your question was a joke.

Along the line of "I was told to buy a box of muffler polish", or the camp favorite "snipe hunt".

I do not know about where you live, but Palm Abrasive in Portland, Oregon sells them. However, any place that sells machine tooling should have the taper reamer you need. If you live in a town of any size, there should be someone near you.

[Greg Downard]

Well Grainger, McMaster has both drills & reams. But they are pricey! Check the yellow book for a Industrial Supply near you. They can get them. May be cheaper to drill straight hole and use a roll pin.