[boothboy]

Nope.that's not it.
BB

[dinger]

A spare tire carrier for a P51 Fighter.

[boothboy]

Very close but not it.
BB

[John long]

I think Brian is on the right track but suspect it is to scribe the center line on a tire to measure toe in.

John L

[boothboy]

Originally Posted by John long

I think Brian is on the right track but suspect it is to scribe the center line on a tire to measure toe in.

John L

Yeah and a pretty nice one at that!
It's yours John.
BB

[John long]

I hope this is not too off topic I but found it fascinating. I had the good fortune to ride in the cab of the Baldwin Steam locamotive operated by the Tenn Valley Rail Road Musium two years ago and the engineer was explaining to me what he was doing as he operated the engine. There are two main levers that control forward motion. The first is the throttle that controls the amount of steam to the cylinders. The second basically does the same thing the transmission does in an automobile and has the effect of changing gears. This provides more torque at start up and more speed with less steem when cruising.

Question. How is this accomplished?

John L

[MARTINSR]

That is a pretty neat old tool, you have some good ones BB.

Brian

[496CHEVY3100]

with a tapered centrifucal cluch which alters gear ratio with rpm

[John long]

Originally Posted by 496CHEVY3100

with a tapered centrifucal cluch which alters gear ratio with rpm

No. The actual ratio does not change as the connecting rod is connected from the piston to the wheel. The effect however is the same as changing gears.

John L

[boothboy]

I believe the second bar controls the timing of the inlet of the steam and has to do with the amount of steam compression. i think that there is certain boiler tubes that deliver some steam earlier for initial start up and movement.
BB

[Joe G]

Originally Posted by John long

....There are two main levers that control forward motion. The first is the throttle that controls the amount of steam to the cylinders. The second basically does the same thing the transmission does in an automobile and has the effect of changing gears. This provides more torque at start up and more speed with less steem when cruising.

Question. How is this accomplished?

John L

That's the vtec lever...lol.

But seriously, the other lever controls the valve setting. A steam engine uses a complicated variable valve linkage that allows the engineer to adjust the valve duration depending on load and speed. A long duration is used for maximum torque at low speed, and a shorter duration is used once the engine is up to speed. It can even be set to zero, so the valves never open (like neutral), or if you go past 'neutral' the valve timing reverses, which makes the engine run in reverse.

It's hard to explain.....

[John long]

Good answers. I think we have to give this to BB Joe. He is pretty close with his answer and was first. As the engineer explained to me. There are a number of ports along the cylinder. A slide rail determines which port the steam enteres the cylinder through. When the locamotive starts out the engineer sets the control so the steam enters at the far end of the cylinder thus pushing the cylinder for the full length of the stroke. Once the train is rolling the lever is moved allowing the steam to enter with the piston having already traveled part way down the cylinder. Hence you get full effect of the steam on start up and only a short burst of steam when you are cruising. Part of the skill of an experienced engineer is coordinating the two controls to optimize the use of fire and water for work performed. So you can see the search for fuel economy is not new. This technology just fascinates me.......How can a few gallons of water and some firewood move that much weight down the tracks?

Your floor BB

John L

[boothboy]

Well I got to tell you that about an hour away from where I live is the Calif State Railroad Museum. My wife won't go with me anymore as I drag any new visitor we get first to the Empire Gold Mine ( biggest producing gold mine in the world up until the 1990's , and the Empire shut down in 1957!) here in Grass Valley and then down to the Train Museum in Sacramento. It's one of the best museums in the USA. I love trains! The control bar your referring to is called "The Johnson Bar" I had to look that up as I couldn't remember it's name. Here's my old desk top picture. I saw this old guy passing through Lawrence Kansas a couple of years ago. It had been a static display in Cheyenne WY. for years in a park but finally got back on the rails. It was on its way back East. Fifteen years ago or so Sacramento hosted a Rail Fair. Old steamers came fron all over the USA to attend. There were Locomotives that were shipped from England! Can you imagine that! And we think we have a expensive hobby! It was absolutely wonderful. There are alot of people who collect private coaches and the hooked up with some of the Engines that were attending. I got my lawn chair and cooler and sat at a crossing out in farm land and watched them arrive. Absolutely breathtaking!

BB

[boothboy]

How about another old tool. I'll bet most of you guys have this one!
What is it and what do you do with it?
BB

[BruceKoukalaka]

Looks like a thread gauge/chaser to me