Post by mbrown on Sept 13, 2020 20:13:48 GMT
Back to work on the handbrake this evening....
The first thing was realizing, after careful scrutiny of my photos, that I had mounted the ratchet too far the left. I had wondered why, having made the parts to the measurements taken from the prototype, why the centre of the ratchet didn't coincide with the centre of the support angle as it appeared to do in "real life". Looking again at the pictures, I saw that I had interpreted the perspective wrong and that in fact, the right hand edge of the ratchet overlapped the tool box on that side instead of coinciding with the edge of the angle.
So I filled the rogue hole by tapping it 5 BA and screwing in a stub of steel with some high strength Loctite, then gently peening the ends over into small countersinks. When it was filed flush it was invisible on one side and only slightly noticeable on the other.
IMG_20200913_174931 by malcolm brown, on Flickr
The pawl was filed up from a tiny piece of 1/8" gauge plate and pressed onto a 3/32" pin.
IMG_20200913_195640 by malcolm brown, on Flickr
... and the thumb lever for releasing the pawl is a piece of 3/16" rod with a tab silver soldered onto it and filed to shape. It was then pressed onto the other end of the spindle. I don't think anything more permanent is needed, given the small forces involved.
IMG_20200913_195731 by malcolm brown, on Flickr
Finally, the "?" shaped pull lever was made from 1/8" plate. I have left this over length and it will, in due course, be silver soldered to a length of LH 3 BA threaded rod to go into the turnbuckle.
IMG_20200913_204645 by malcolm brown, on Flickr
And finally, a shot intended to be as close to the close up picture of the full size handbrake as possible. It shows that I haven't got it perfect, but I think it is a decent representation of a classic Orenstein and Koppell brake lever.
IMG_20200913_204540 by malcolm brown, on Flickr
More next week, I hope.