Re: boat propulsion - miniature computer-controlled steam plant?

On 10/03/2024 16:55, Jim Wilkins wrote:

"Peter Fairbrother"  wrote in message news:usknjc$329n7$1@dont-email.me...
 [*] technically it's a CNC-converted BCA jig borer, but it has hefty
upgraded ballscrews, improved lateral stiffness and is pretty much only
used on ceramics with abrasive diamond tooling; though I can fit an ER20
collet shaft and a slower motor. I also have a manual BCA.
 ------------------------------
 Nice!
I have two Henry Hauser vertical mills of similar vintage

Oooh ... :)
, unfortunately

lever feed for production instead of leadscrew. The seller told me they made WW1 artillery fuses.

I actually have six BCA's, though only two are in working use.  I was picking them up for about £200 each a few years ago and thought to recondition and/or cnc-convert them, but that plan went agley and they are now sitting in my nice dry airing cupboard along with some ML10s and other stuff I have no room to use. Must get a bigger workshop!
The BCA is based on and almost identical to a Boley/Leinen design from the 1930s (which was based on an earlier 1880's design). I only have one WW2 example, badged Excel (apparently they rebadged someone else's work), but I believe it was used to make jigs for anti-aircraft shell fuzes. The rest, like the BCA name, are post-war.
A story I heard, don't know whether it is true or not, is that just before WW2 the British Government ordered Excel to make lots of BCAs. Excel (or whoever) then continued to pay design royalties to Boley/Leinen right through 1940. Ouch! Postwar, the design rights were considered  to be spoils of war.
But Tenga still make them - basically a 1880 design - at £10,500 each last time I checked.
That old cast iron is still going strong - and 50 years of settling can't hurt :)

Did you do the CNC conversion?

Yes.
Peter Fairbrother