Thread: Ferodo Drilling Chuck - tell me more?

It seems to be an adjustable depth stop, with a combined counterbore, countersink, or other finishing device. Yours is set up to produce counterbores. Different inserts would be used for the other features.

Have you taken it apart yet?

Cheers,
Joe

Hi,
As a wild guess, for drilling rivet holes in Ferodo break linings.
Regards

Originally Posted by joe greiner

It seems to be an adjustable depth stop, with a combined counterbore, countersink, or other finishing device. Yours is set up to produce counterbores. Different inserts would be used for the other features.

As long as the bit is flat - which seems to be an unusual feature of the device. The bit supplied is the same one, apparently, as the one in the patent drawing.

Originally Posted by joe greiner

Have you taken it apart yet?

Just got it apart after a few hours soak in WD40. See pics next post.

Originally Posted by A Duke

As a wild guess, for drilling rivet holes in Ferodo break linings.

Seems like a reasonable guess to me ... so it might be an old automotive tool, from the 1930s.

It didn't show up at all on Google for me ... though they say we all get different results from Google depending on what Google knows about us ... maybe someone else will find something else about it. Or else this thread could be all there is.

- Ian -

The pull-apart pics:
(thread is left-handed)

repeated post - snafu - can't delete.

The brake shoe theory seems to check out correct.


I found a little bit about such tools in a book "Dyke's Automobile and Gasoline Engine Encyclopedia", 1920 (Google Books). If anyone is going to read this book outside the USA, they're going to have to use VPN set to a US IP address (I used Opera, the latest versions of which now have free unlimited VPN built in without adware - nice). Here's a clip from the relevant page (note that this is a slightly different US tool):
ykes Automobile and Gasoline Engine Encyclopedia 1920 p690 clip.JPG


And a fellow called kelsham on a forum thread brake lining material | MIG Welding Forum posted some years ago "I used to carry out this sort of job [i.e. relining brake shoes] in the 1960s I worked for a Mintex agent. We used to clamp the material to the band and drill a suitable sized hole using the rivet hole as a guide. We had countersink bits to sink the hole down to the right depth. I think I still have a couple of the bits in my toolbox." and later mentions Ferodo - though it's only a loose association.


Not a lot on this topic on the net. Seems to be a very obscure tool curio.


- Ian -

Brake linings and woodwork.
Reminds me of the Wadkin DR30 bandsaw a mate's father bought from a brake relining business down the Southern Highlands.
Great saw with about 10mm coating of asbestos all over it.
H.

I'll stop posting about this, I promise. But before I do, I'll pass on for posterity what I've learned about this little chuck, especially since it has never made it onto the web before. If I was to give a name to it, it would be a "drilling and counterboring tool for brake-lining rivets". Even though it would be possible to swap the bit for other functions (like straight drilling) it really seems to have been made for this one operation in old-time drum-brake lining replacement.

As the patent says, the tool is composed of three separate parts, the body (the inside part); the collar (i.e. the covering shroud that is screw-threaded onto the body); and the bit. The tool has two operating positions: 'lock' and 'release'. The bit is held fast when in the lock position. When you want to adjust the depth of the bit (or remove it), you turn the body 1/4 turn (90 deg) clockwise with respect to the collar, which is the release position.

When in the release position, you have aligned the edges of the flat shank of the bit with two wide axially-oriented grooves, diametrically opposite each other, on the inside surface of the collar (seen in one of the pics above), and that allows the bit to slide out along the grooves. You'll also see that the shank of the bit has serrations along its side edges, with the same pitch as the screw thread inside the collar. So when you turn the collar to the 'lock' position, the bit is turned away off the wide grooves, and onto the screw threads inside the collar, which engage these serrations. When in lock position, the engagement of the serrations with the threads stops the bit from moving.

In the pics below, you can see firstly the tool in 'lock' position; and secondly in 'release' position, with the bit removed. Note too in the 2nd photo, the serrations along the shank of the bit.

Ferodo chuck lores 12.jpg Ferodo chuck lores 11.jpg

In practice, when adjusting the tool, you hold the 'collar' because that's the biggest external part to hold, and then turn the knurl on the 'body' to lock and release the bit. Due to the left-handed thread, which is counter-intuitional, it is easy to get confused and turn the body too far one way or the other, and get it all jammed up. So it seems easier to hold the collar so that the stamped word 'lock' is facing up at you, and that way, you can see the stamped arrow for the locking direction. That eases any confusion. And that's how I've photographed it too.

Finally, as you can imagine, the whole thing works a lot better if the screw threads are thoroughly greased by working a moderate amount of grease with your finger into every thread on both collar and body, and into the serrations on the bit. Since mine had been lying unused for, I'd say, at least 60 years, it was dry and jammed easily. But now with a good clean and a grease, it's quite smooth.

Well that's it ... who knows, someone else may have one of these, and now it's got a write-up here that they can read.

-Ian-