Making cotter pin hole in shackles

wrndln

Well-known member
I have a slightly used set of original Ford shackles I need to put cotter pin holes in. I took the shackles to a local one man machine shop to see if he could drill the holes in the shackles. He tried with his milling machine, but said the shackles were too hard. He said maybe a carbide milling or drill bit might work, but he didn't have any carbide bits. I don't have a milling machine, but do have a very well made drill press. If anyone has had the same situation as I have and has put cotter pin holes in the very hard Ford shackles, would you post a response on how you did it. The picture below shows the shackles that need holes in the bottom of the picture. Any help would be appreciated.
Rusty Nelson
 

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I have used a mill with a 1/8 center cutting mill bit before with no problem.
May need to use a carbide burr to get enough thread off to not make the bit wobble and break. Might try a little heat to get red at the entry spot.
 
Rusty, while you are buying a drill, see if you can get a 9/64" to have the correct size. I have included a portion of the original print so you can see where to locate the hole(s).

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there is a guy in Portland that sells carbide drill bits. they are $6 ea, but they do the job. I take a 7/16 hex nut and drill a centered hole in it for a guide. then put the nut on the shackle and set it up in a drill press. by real careful when break through the other side it will twist the carbide right off. his name is Ron 503 881 0178.

he does have the correct size like Brent said
 
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A drill press isn't ridged enough too be poking holes in the shackles...you need a mill.
Use carbide end mills the correct size..
 
I'm just curious. If they're Ford shackles why don't they come with the holes already drilled?

Yea something got overlooked and Charles here caught it... Should of had holes to begin with...

Are you sure someone didnt just undo the nuts and shear off a cotter key thus filling the hole?

Ive done that before and yes it can look like no hole ever existed...
 
Even Ford wasn't perfect all the time. I replaced a shackle recently that was NOS when installed 40 years ago. It was worn badly compared to the other side. Turned out the grease hole had not been drilled.
 
I believe Ford made shackles that fit model A's after model A production was finished that didn't have cotter pin holes - i.e. replacement shackles. I have 4 shackles without cotter pin holes, so it isn't a mistake. I have also seen original Ford shackles on eBay that fit model A's without cotter pin holes. I think maybe that lock washers and regular nuts were used on later cars.
Rusty Nelson
 
Pretty sure that ford made shackles in late 1931 that were not drilled.
Probably used them into the early V-8 era also.

Ray
 

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I think you will find that the replacement shackles made without cotter pin holes also have oversize threads. Hence, the nut is a tight fit on the thread. The nut has to be wrenched on the entire distance and therefore a cotter is not required.
 
I had ten sets of shackles without holes. and I still have four sets left and I have not run into a problem with the threads. all of the ones that I still have and the ones I sold were the latest version why that is beats me. and a drill press works just fine on drilling the holes, where the problem is when you hit hard spots in the shackle and when the drill breaks through the other side it has a tendency to twist the carbide right off the end of the bit.
 
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