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+--- Thread: Clutch toggle lever pins (/showthread.php?tid=1868)
Clutch toggle lever pins - Ian M - 11-10-2018
Would anyone object to an Austin 10 question? It's just that I'm struggling to obtain information via the relevant club and forums, and feel that the Austin 7 folk are more inclined towards technical discussions, so might be better placed to advise. I do own a couple of Sevens, by the way!
The car is a 1934 10/4, a late chrome rad model. I'm nearing the end of a clutch rebuild, but there's one point of detail that isn't quite right and I don't want to put it all back together until I'm 100% happy with it all.
The three clutch toggle levers have hardened steel pins, similar to a 7, but of smaller diameter. The ones on my car are badly worn and must be replaced. These are tricky things to get hold of, but I did find one supplier. The original pins have a radius on each end, which ensures that there are no edges that would protrude from the toggle lever post. This is important, in order to prevent any possible fouling of the recesses of the pressure plate. However, the replacements lack the radius, although they do have a slight chamfer. I've tried putting one of the pins in my lathe and using a small sharpening stone to form a radius, but the metal is just too hard to make any real progress.
One suggestion is that I try making a set myself, out of silver steel. However, I'm not sure that my lathework skills are sufficient to get the pins just right, plus I've not worked with silver steel before. I presume that heat treatment would then need to follow, for hardening, but I have no prior experience of this.
Any advice, please? I've attached a couple of pictures, one showing the new and old pins, and the second illustrating how the edges of the pin-ends protrude slightly from the post.
Many thanks.
RE: Clutch toggle lever pins - Ian Williams - 11-10-2018
Silver steel is easy to turn, heat it to red and quench in oil, polish and temper down to what ever colour you desire then quench again. However why not just case harden some bright steel, that is even more straight forward and case hardening powder should not be hard to obtain in the UK.
RE: Clutch toggle lever pins - jansens - 11-10-2018
I think I would just grind the ends to the curve, just slowly not to over heat them? On my 7 the new clutch pins were too long and fouled the clutch so I did just that. Just slowly ground them down till they fitted.
Not sure it that was a bad thing now you've asked!
Simon
RE: Clutch toggle lever pins - Ruairidh Dunford - 11-10-2018
Quite a few of the pins supplied today are slightly too long - I grind them down to suit, they work fine after this in my experience.
RE: Clutch toggle lever pins - Ian M - 11-10-2018
Thank you, chaps!
I'll first try the idea of grinding the ends of the pins to the desired radius. Should I persevere with my lathe and sharpening stone method, which clearly requires a fair bit of time and patience, or resort to something more brutal? The other idea I considered was the use of an electric grindstone and offering up the pin in a small chuck, which could be rotated. However, that latter would offer less control in terms of material removed. A pity that I don't have more than three of these pins at my disposal just now, as there isn't really any margin for error unless I get some more!
RE: Clutch toggle lever pins - jansens - 11-10-2018
Practice technique on something else first. Brutal seemed to work for me. Just a flat linisher with sandpaper on it!
RE: Clutch toggle lever pins - Steve Bryant - 11-10-2018
Put the pin in a drill and grind the end to a radius on a grinding wheel while the drill is turned on. Easy fix.
Stephen
RE: Clutch toggle lever pins - Hedd_Jones - 11-10-2018
Angle grinder!. One of the most versatile tools in the shed when used with thought and care.
I'm hoping to machine about 1inch of rubber off the back wheels of my traction engine with one this winter. We shall also use a lathe in this excercise but as a mount for the grinder rather than to turn the wheel.