Cotter pins
 

A question was posed to me and I have no idea what the answer might be.

Did Ford use galvanized cotter pins back when or did he save money and use carbon steel cotter pins?

Thanks.

Re: Cotter pins
 

He used cadmium plating

Re: Cotter pins
 

Originally, Henry used cotter pins with no finish.


Chris W.

Re: Cotter pins
 

I would like to ask another question on this subject. Are the stainless cotter pins strong enough? I have never known if the stainless bolts are as strong as the grade five bolts for example.

Re: Cotter pins
 

Since the whole point of cotter pins is that you can bend them with pliers, or often just your thumb, I would consider their strength to be minimal. You could probably make them out of plastic if you wanted. Their job is to prevent the nut from working loose due to vibration, there's virtually no strength required for that.

Edit: There is a valid debate about whether it's a good idea to re-use cotter pins since the act of setting/bending them fatigues the metal. I try not to re-use unless I don't have a suitable replacement. Not a hard-and-fast rule though.

Re: Cotter pins
 

My dad straightened rusty nails and kept old screws - depression mentality. Times have changed. I would not recommend reusing a cotter pin!!

Re: Cotter pins
 

In a past life, in a pinch, I've used a nail to replace a cotter pin. I'm sure jillions of others have done the same thing.

Re: Cotter pins
 

My question was more toward the nuts and bolts. I have used stainless nuts and bolts where I don't want rust to be seen and wondered if the strength was the same as the standard steel bolts. Jack

Re: Cotter pins
 

Chris is correct. i have used stainless cotter keys. you would think they would be softer, but they are harder to bend. for the most part I used Cad or zinc plated cotter keys.

Re: Cotter pins
 

There are many grades of stainless bolts, just as there are with steel bolts. The ones you get at the big box store are usually as soft as a grade 2 steel bolt. You get what you pay for and stainless is expensive.

Re: Cotter pins
 

A common question is whether stainless steel is stronger that a grade 5 or grade 8 bolt. Stainless commonly comes in grades 18.8 (304) or T316. Stainless steel bolts are rated for corrosion resistance. Bolt strength is rated in PSI (pounds per square inch). A stainless steel bolt has the same PSI rating as a grade 5 bolt (125,000 PSI). A grade 8 bolt has a stronger rating with a PSI of 150,000.


From the above I would say that a SS Cotter Pin is stronger, I personally stay away from the china bolts and cotter pins



the above comes from:

https://www.nutsandbolts.com/v10-sta...eel-grade.html

Re: Cotter pins
 

This is what can happen in a Model A differential if you neglect to install a cotter pin on the end of the drive shaft. The nut came loose and backed off until it hit the rotating carrier. The carrier cut the nut in half (see the two pieces in one of the photos) the nut pieces got between the ring and pinion and did a number on the pinion gear.

Tom Endy

Re: Cotter pins
 

Thanks Holdover, just what I wanted to know. Jack

Re: Cotter pins
 

How about hammer lock cotter-pins? I don't think they were available - at least in the US.

https://en.wikipedia.org/wiki/Split_pin

Joe K

Re: Cotter pins
 

So what colour were the cotter pins again?

Re: Cotter pins
 

Hi Tom,
I had that exact pinion gear failure back in 1964, and it disabled my Coupe for a few years until I could afford to fix it. The pinion in my Coupe broke loose while I was driving at speed on a highway. What a mess it made.
Re stainless steel, it will cause galvanic corrosion of most carbon steels it comes in contact with. So it isn't good to mix stainless with other grades of steel.

As for the various types of stainless / corrosion resistant steels, this site defines the various alloys:
https://continentalsteel.com/stainless-steel/grades/

Re: Cotter pins
 

Seems the older cotter pins were thicker and softer compared to the box I have, even the replacement cotter pins I got from Snyders. Softer let's you form it more to the nut I'd imagine where it can't start loosening at all?

Re: Cotter pins
 

Interesting to note too is that the form of today's cotter pins are not the same as those available during the Model A era. Modern cotter pin heads are kind of diamond shaped, while those made back in the day had rounded heads. You can't get those round head cotter pins today, so if you have an old jar of themlaying around I bet a fine point car restorer would pay good money for them.

Re: Cotter pins
 

But, you can get round head cotter pins. Here's a picture of what I have:

Re: Cotter pins
 

As it relates to cotter pins I agree with Alexiskai. The cotterpin just prevents the castle nut from backing up, so the material technically does not matter. One material may be easier to bend than another. When it comes to bolts, then the material matters.