What are these metal pins called (Dissasembling my Kity 636 for restoration)

[Phill05]

Where I come from, if you want a swede, you still ask for a turnip.

An when I was on the farm if the farmer wanted one for dinner it was a Turnip but if he wanted you to feed sheep it was Swede, and if he wanted a cotter pin it was the split pin to go through the hole in the nut you bent one leg one way to stop it unscrewing.

 

[Fergie 307]

But not the Screwfix one. Cheap pin punches just produce tears and frustration. The minimum I would buy is Sealey, but Kennedy from Zoro and anything from RS would do.

Not only do they mushroom ike a damp forest, they bend because they are too long for their diameter.

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Just for the record, I offer two ways that I have been told are preferred:

1) start the pin moving with a short parallel punch (e.g. Clarke ET101 8-Piece Short Drive/Pin Punch Set - Machine Mart - Machine Mart) and then drive it out the rest of the way with a long parallel punch (at this stage, the Screwfix one would be OK). The short punch has less inclination to bend.

2) use a proper roll pin punch - see how the end is a different shape (Roll Pin Punch Set 9pc 3-12mm Metric | AK9109M | 1 Year Guarantee | Sealey

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The key point is that the force needed to break the pin loose is a lot greater than that needed once it has moved a little. Once the initial movement is seen, almost anything can be used to finish the extraction.

It is a roll pin. In practice easiest to start it off with a punch larger than the pin. So if the pin is 5mm, start using a 10mm diameter punch. Make sure the end of the punch is flat and thst you hold it straight on the end of the pin. Tap the pin in level with the shaft using the large punch. Now switch to a punch slightly smaller than the diameter of the pin to drive it through and out. If you try and use a small diameter punch initially you will either bend the punch or damage the end of the pin. You can get purpose made punches with a small pin in the end that fits in the hole in the roll pin to keep it aligned, but v expensive and really not necessary.
Ideally you should use new ones on reassembly, but providing the old ones are in good shape and still grip the hole there is really no reason why you shouldnt re use them.

 

[deema]

Cheap tools usually lead to tears……BUT I’ve had a set of Silverlime parallel pin punches for years, they have taken apart a lot of stuff…..many many wood working machines. I’ve pounded in them with all sorts of heavy hammers and they are brilliant. Cheap as chips, and bought from Screwfix. Someone I know bought a very expensive set, beautifully made, very shiny, in fact they are too nice looking to use.

These are the jobbies I would highly recommend to anyone.

https://www.screwfix.com/p/parallel-pin-punch-set-5-pieces/7549v

 

[J-G]

We learn a ton of stuff before we discover that sometimes the name we first learnt is wrong or alternative !

I can go along with that. Many years ago (late 40's/early 50's) my father asked me a 'trick' question - - - What is the salary of the Prime Minister? - His answer was "Zero The office of PM has no salary, he is paid for being 'First Lord of the Treasury'.

This was true up until 1936 but not at the time Dad asked - that fact has annoyed me ever since I found it to be a lie (which I had passed on unwittingly ) it has however, made me question virtually everything that anyone ever tells me is a 'fact'.

 

[Limey Lurker]

It is a roll pin. In practice easiest to start it off with a punch larger than the pin. So if the pin is 5mm, start using a 10mm diameter punch. Make sure the end of the punch is flat and thst you hold it straight on the end of the pin. Tap the pin in level with the shaft using the large punch. Now switch to a punch slightly smaller than the diameter of the pin to drive it through and out. If you try and use a small diameter punch initially you will either bend the punch or damage the end of the pin. You can get purpose made punches with a small pin in the end that fits in the hole in the roll pin to keep it aligned, but v expensive and really not necessary.
Ideally you should use new ones on reassembly, but providing the old ones are in good shape and still grip the hole there is really no reason why you shouldnt re use them.

The only thing I would add, is to put a drop of WD40 on the protruding part; there's often rust there that can benefit from a bit of lube.

 

[okeydokey]

One of my cars (might have been a 2CV) had double roll pins one inside the other definitely need correct sizes punches

 

[Robbo3]

Nothing like a 'Cotter Pin' - -

This is a Cotter Pin :
View attachment 150567
It has a tapered flat, a 'Roll Pin' is hollow spring steel with a split to allow for a small amount of compression.

Agreed.

Turnips, swedes & mangels are different types of root vegetables.

 

[Fergie 307]

One of my cars (might have been a 2CV) had double roll pins one inside the other definitely need correct sizes punches

Renault used the same on their driveshafts. I still have the factory Facom punches fot them somwhere

 

[Scruples]

I don't need to. If Amazon sellers say any different - they are WRONG!

I've known what a cotter pin looks like since I repaired my first bike, sometime in the 50's

Not just Amazon it seems the whole world disagrees. But, if you're happy thinking you know better, then that's OK with me.

 

[deema]

@Scruples @J-G
Since there was debate I thought I’d look it up in the universally accepted bible of Engineering stuff, the Machinery’s Handbook, issue 31 to be precise.

What the pin is that is being questioned is a rolled spring pin. It is not a Cotter pin. A cotter pin is any form of pin that holds two pieces together tightly under compression or tension. J-G has shown a recognised example of a Cotter pin.

 

[dizjasta]

Originally the term "Cotter Pin" was applied to the shear pin used in artillery designed with a Cotter Breech. It looks like the term can apply to a any pin arrangement resisting a shearing force.

 

[XTiffy]

As with all things every country and trade has a different vocabulary. In this case in the Uk the agreed term is a roll pin. The cotter pin referred to was tapered and had a nut/washer to hold it in place and pull it tight. Then we get onto "woodruff keys".....debate!

 

[J-G]

Originally the term "Cotter Pin" was applied to the shear pin used in artillery designed with a Cotter Breech. It looks like the term can apply to a any pin arrangement resisting a shearing force.

Thanks for that - I've been trying to find a decent reference to the etymology of the term 'Cotter' but naturally language corruption has taken its toll

 

[J-G]

As with all things every country and trade has a different vocabulary. In this case in the Uk the agreed term is a roll pin. The cotter pin referred to was tapered and had a nut/washer to hold it in place and pull it tight. Then we get onto "woodruff keys".....debate!

Sorry to dis-abuse your explanation but the Cotter Pin I referenced is in fact a parallel pin with a flat machined at an angle making a taper on a part of it.

Yes, Woodruff Keys are also subject to mis-understandings and incorrect naming!!

 

[MikeK]

Sorry to dis-abuse your explanation but the Cotter Pin I referenced is in fact a parallel pin with a flat machined at an angle making a taper on a part of it.

I don't know why you are so quick to dismiss @XTiffy's comment. There are plenty of examples in this thread, and others on UKW, where names for the same item vary by geography. Does that mean all but one are wrong?

Along a similar concept, an Australian Ford discussion board, with an international membership, became embroiled in "tyre" versus "tire" and "aluminium" versus "aluminum" (similar to sharpening threads here). The owner had to add "tire" and "aluminum" to the censor filter and covert them to the Australian version in order to appease the few members who adamantly refused to accept any other spelling and would not participate in discussions if the foreign member used his or her regional spelling.

You will likely be disappointed if you go into any U.S. or German hardware store and ask for a cotter pin if you are expecting to find a tapered pin with a nut on the end.

 

[sams93]

It is a roll pin. In practice easiest to start it off with a punch larger than the pin. So if the pin is 5mm, start using a 10mm diameter punch. Make sure the end of the punch is flat and thst you hold it straight on the end of the pin. Tap the pin in level with the shaft using the large punch. Now switch to a punch slightly smaller than the diameter of the pin to drive it through and out. If you try and use a small diameter punch initially you will either bend the punch or damage the end of the pin. You can get purpose made punches with a small pin in the end that fits in the hole in the roll pin to keep it aligned, but v expensive and really not necessary.
Ideally you should use new ones on reassembly, but providing the old ones are in good shape and still grip the hole there is really no reason why you shouldnt re use them.

Thankyou to everyone for advice on this! I bought a set of parrallel punches from Toolstation and then this is is exactly what I did in the end and they are out! Got a couple more to remove from some other parts of the assembly so I will bear all of the advice in mind.

 

[XTiffy]

Thank you MikeK,
I worked with the US Navy (with, not in!) for more than five years and never had an argument over spelling/pronunciation of English words or their meanings. If an individual was talking on a technical subject, you would seek to understand what they were saying or describing and compare terms.
The only convention we in the RN used that upset them was U/S to mean un-serviceable. I do not understand why certain individuals wish to create division where none exists or split hairs.

 

[Phil Pascoe]

We always took U/S to mean useless. NFG to mean no f ing good and 4F to mean f ing f er's f ing f ed.

 

[XTiffy]

Phil Pascoe,
I was quoting Royal Navy parlence, never had need of your abbreviations! As I was in electronics, we would routinely put a sticker on a circuit board or component as U/S, unserviceable ie don't use until repaired or replaced.

 

[deema]

The Machinery’s Handbook is a global ‘bible’ of mechanical engineering parlance. You find it in Europe, US of A as well as the rest of the world. I’ve never come across a machinist or engineer anywhere in the world who didn’t have access to a copy. It’s been going since the Stone Age and each new addition just gets thicker to accommodate the latest developments. Just Saying