Sounds like that bit of Heath Robinson (since you're in the UK) mess was just to avoid paying royalties to Clarence W. Spicer. https://www.machineservice.com/products/universal-joints/history-behind-the-universal-joint/ On Wednesday, July 7, 2021, 7:30:05 PM MDT, andy pugh <[email protected]> wrote: On Thu, 8 Jul 2021 at 00:39, John Dammeyer <[email protected]> wrote:
> But for metal a spiral, or at least spiral point is a must I think. Time to > do a bit more tuning but impressed as how well it works. I power-tapped a bunch of holes into EN24 with a conventional straight-flute hand tap at the weekend, though it was a bit heart-in-mouth. Bit of a story here. a slightly epic field repair. (literally, in a field) I play with an old fire engine. (US: fire truck). It belongs to the students of my old university (Latin: Almer Mater). They were invited to an event about 50 miles from their base in South Kensington last weekend, by someone they know from the Kew Bridge Steam Museum https://en.wikipedia.org/wiki/London_Museum_of_Water_%26_Steam (home to the second and third biggest steam engines extant). [1] When I say "old" I mean that the fire engine was built in 1916. The fire engine has an overhead worm drive differential, and drive into that is via a "box joint" which is a crude sort of universal joint where a square "knuckle" on the differerential input shaft is driven by a hollow square. The outer faces of square knuckle are radiused, and two bronze "slippers" fit between those and the outer box (it's odd that there are only two, but the knuckle is rectangular, with the slippers on the long faces, to make it square) The knuckle mounts on a taper, pulled up by a nut. There are two keyways at 90 degrees. But we only use one, as two keyways is stupid. (It took about 30 years of our ownership to realise this, but with two keys and a taper either only one key fits, or the taper can't pull up. It is kinematically redundant, in a bad way) _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
