Wessex crank up

I took my ex B17 APU Homelite (as in this month's SEM) for walkies on Sunday and went to my club's crank up at Nunney Catch in Somerset. It was one of those brilliant hard winter days that make engines run well and the exhibitors look for their Thermos and gloves. As usual, it was well attended and I counted eighty cheerful people and thirty nine engines. There was the usual broad selection of engine types present from a JAP outboard engine to a very nice Blackstone amid the usual plethora of Listers and Wolseleys. There are always bits for sale and I bought a 1930's bolt-on-the-wall garage equipment type battery charger for the fun of seeing if it works and a cheap Dremel type tool (seven quid!) which had lots of unused cutters, pads, wheels, and a wide range of tiny diamond tipped grinders of every shape in geometry.

I think a number of us try to take something unusual along in addition to an engine - there's the petrol tin man with his dedicated trailer display that opens up like a Tardis, the oil can man, the chap that collects insulators and the rarely seen plug man with his huge collection of spark plugs. Last time, I took along a barrel off a Bristol Aero Engines Pegasus XVIII, but on Sunday I took the three cased instruments I've started to collect, a laboratory vane capacitor, a Wheatstone Bridge and my aluminium cased Lightning servo tester. They certainly attracted attention and comment and this has spurred me on to go and look at some more this evening! If anyone on this NG has similar stuff they might want to get rid of for not a lot, please let me know off list. Similarly, I've seen a trader several times at the Sodbury Sortout who always has these instruments for sale and if anyone can tell me who he is and has contact details, I'd be most obliged.

Anyway, the Homelite was not behaving itself at all well. It ran flat out OK, but would not easily respond to regulation of the carburettor. Being a direct lift carb, there is only the one screw which controls the fuel flow and the most careful adjustment would only make it hunt from a couple of hundred rpm to (say) 3,000. It ran like this for a while after I'd decreased the oil/petrol ratio, thus richening the mixture, but no-one could describe it as happy. For the record, flat out is generating over 35 volts, so it is not designed to run that way.

I'd had the carb apart the night before and it is a very well made piece of kit and complicated for one of its type. I found some dirt, but nothing desperate and the non return valves were working fine, so now I'm rather stumped. Any ideas anyone?

Following the usual raffle in aid of club funds, we all went home, all packed up and on the road before dusk.

Regards,

Kim Siddorn

Reply to
J K Siddorn
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Does it have those nice Tungar bulbs in there, or the somewhat less exciting metal rectifers?

Thats what comes orf writing about how well it goes in SE magazine. It could be like the infamous Ford VV carburetter which once taken apart would never ever work properly again!!

Regards

Philip T-E

Reply to
Philip THornton-Evison

The battery charger is about two feet long and has a finned rectumfrier that almost fills the entire frame at the bottom. It's rated at 210 volts, but I don't suppose it will mind a few more volts.

Wot's a Tungar bulb? Do they flower in the spring?

The Peggy 18 barrel came from a crashed Wellington bomber in the Brecon Beacons. I've two of them and twenty years ago started to build a vee twin out of them. Equipped with Pratt and Whitney Wasp pistons and Merlin conn rods, it would have a swept volume of 4.25 litres. I got as far as having a pattern made and a crankcase cast and machined, but ran out of steam at that point.

I'm not going to talk about the Homelite, it might hear me!

Regards,

Kim Siddorn

Reply to
J K Siddorn

Tungar bulb rectumfrier is a thermionic diode with TUNsten cathode and GRAphite anode, so I guess it should be called a Tungra ;-)

Reply to
Nick Highfield

"J K Siddorn" wrote (Snip):-

Eek! Was it destined for a Vincent frame?

Reply to
Nick Highfield

Ah, its got a TUNGsten filament and ARgon filling. hence the name :-) They glow a nice sort of purple colour when running. An early design of low voltage/high current rectumfrier. Got a couple of nice new ones in the shed somewhere.

Regards

Philip T-E

Reply to
Philip THornton-Evison

I stand corrected.

Reply to
Nick Highfield

Talking about Rectumfriers, I've always hankered after a mercury-arc rectumfrier, prefereably a small one producing 50volts (I can use it on my

1930's Strowger then ), but they seem to be impossible to find, I can't even remember the last time I saw a Tungar up for grabs.

Andy G "> >

Reply to
Andy Greening

50 volts is a bit of an odd one, its too low for a conventional hermionic MV rectifier, (yes I do have one or two about my person) and too high for a Tungar one. What sort of current are we talking about here?

Regards

Philip T-E

Reply to
Philip THornton-Evison

I believe that the London Underground still has a few, although probably rather higher ratings than you are looking for...:-))

Note that they can't be handled/sold any more by ye and me as they are classed as a hazardous article due to the Mercury content. Even the old timers with mercury switches (which I was going to suggest to young PTFE the other week) are technically hazardous goods.

Kind regards,

Peter

Peter Forbes Prepair Ltd Luton, UK email: snipped-for-privacy@easynet.co.uk home: snipped-for-privacy@easynet.co.uk

Reply to
Prepair Ltd

Mercury, ah yes, I remember that stuff. It's a swine to machine in the lathe. Is mercury that nasty. What are the restrictions on owning it?

John

Reply to
John Manders

When I was a kid, I broke dozens of these things for scrap. 8-(

-- Die Gotterspammerung - Junkmail of the Gods

Reply to
Andy Dingley

Well the current can be upto 1k amps, but from home I'm after a small one of maybe 10 amps. It would be nice to have a really small Mercury-arc one glowing away on the mantle-piece! This could of course be any voltage!

Lovely technology, you can see what is happening. Not like all this smoke driven black plastic stuff.

AG

Reply to
Andy Greening

The UV would fix SAD too....

If you like mercury arc rectifiers, look up a greek sculptor named Takis.

-- Die Gotterspammerung - Junkmail of the Gods

Reply to
Andy Dingley

We used to have a home battery charging set made up by my stepfather, last seen in about 1970 when it was still working. Used a four-pin mercury rectifier, direct heater anode and cathode. Variable resistor, tranny and two 1/4 paxolin panels for base and front.

Worked for Donkey's years and never had a breakdown.

I think it was chucked out when he died back in '71, but I'll ask my stepsister just in case if you're interested.

Peter

-- Peter & Rita Forbes snipped-for-privacy@easynet.co.uk Engine pages for preservation info:

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Reply to
Peter A Forbes

Sounds , I'm certainly interested.

Thanks

Ag

Reply to
Andy Greening

OK, I'll give her a call and see if it is still there.

Peter

-- Peter & Rita Forbes snipped-for-privacy@easynet.co.uk Engine pages for preservation info:

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Reply to
Peter A Forbes

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