Office of Steam Forum for Model & Toy Steam Gas & Hot Air Engines

Gil, fine machine!

What's the phasing on the engine?

I'd be very interested in seeing the difference between air vs steam.

 
What I noticed when running my make shift Märklin compound: When 180 phase I don't think running on air  impact performance badly* even though under steam the subsequent expansion wouldn't be there. But at 90 degrees,  noticeable impact. My setup has a timing chain but your fine engine is more suitably engineered.

*My air compressor regulator isn't very accurate so it wasn't exactly the same pressure.

Gil, fine machine!

What's the phasing on the engine?

I'd be very interested in seeing the difference between air vs steam.

 
What I noticed when running my make shift Märklin compound: When 180 phase I don't think running on air  impact performance badly* even though under steam the subsequent expansion wouldn't be there. But at 90 degrees,  noticeable impact. My setup has a timing chain but your fine engine is more suitably engineered.

*My air compressor regulator isn't very accurate so it wasn't exactly the same pressure.

I believe all triples are constructed with crank arms 120 degrees apart. Compounds are 90 degrees apart. I am ready to be corrected if wrong. Receiver size (volume) is also important in delivering the correct charge to the next cylinder in line. All scale model triple expansions I have seen have the same 120 degrees offset of crank arms whether built for air or steam. Remember they also should get some power from the final expansion from a vacuum created by the condenser. You can replicate this by putting a vacuum on the exhaust of your compound.

that is a very finely crafted piece of machinery, it would be a treasure for anyone's collection.

Quote from: CBWho on October 02, 2019, 11:19:40 pm

Gil, fine machine!

What's the phasing on the engine?

I'd be very interested in seeing the difference between air vs steam.

 
What I noticed when running my make shift Märklin compound: When 180 phase I don't think running on air  impact performance badly* even though under steam the subsequent expansion wouldn't be there. But at 90 degrees,  noticeable impact. My setup has a timing chain but your fine engine is more suitably engineered.

*My air compressor regulator isn't very accurate so it wasn't exactly the same pressure.

I believe all triples are constructed with crank arms 120 degrees apart. Compounds are 90 degrees apart. I am ready to be corrected if wrong. Receiver size (volume) is also important in delivering the correct charge to the next cylinder in line. All scale model triple expansions I have seen have the same 120 degrees offset of crank arms whether built for air or steam. Remember they also should get some power from the final expansion from a vacuum created by the condenser. You can replicate this by putting a vacuum on the exhaust of your compound.

Gil !
Thank you for your reply. Food for thought!

I haven’t thought of vacuum making a power boost except in Newcomen engines. Are the condensers with vacuum simply a can with a 1 way check valve? I suspect the effect would boast even simples?

I have an RPM gauge, pressure gauges, dynamos and generators so could record a lot of numbers to see if such a device would boost power. I think I have a metal can with a cover and I know I have metal check valves... mmm...

Quote from: RedRyder on October 03, 2019, 07:19:04 am

Quote from: CBWho on October 02, 2019, 11:19:40 pm

Gil, fine machine!

What's the phasing on the engine?

I'd be very interested in seeing the difference between air vs steam.

 
What I noticed when running my make shift Märklin compound: When 180 phase I don't think running on air  impact performance badly* even though under steam the subsequent expansion wouldn't be there. But at 90 degrees,  noticeable impact. My setup has a timing chain but your fine engine is more suitably engineered.

*My air compressor regulator isn't very accurate so it wasn't exactly the same pressure.

I believe all triples are constructed with crank arms 120 degrees apart. Compounds are 90 degrees apart. I am ready to be corrected if wrong. Receiver size (volume) is also important in delivering the correct charge to the next cylinder in line. All scale model triple expansions I have seen have the same 120 degrees offset of crank arms whether built for air or steam. Remember they also should get some power from the final expansion from a vacuum created by the condenser. You can replicate this by putting a vacuum on the exhaust of your compound.

Gil !
Thank you for your reply. Food for thought!

I haven’t thought of vacuum making a power boost except in Newcomen engines. Are the condensers with vacuum simply a can with a 1 way check valve? I suspect the effect would boast even simples?

I have an RPM gauge, pressure gauges, dynamos and generators so could record a lot of numbers to see if such a device would boost power. I think I have a metal can with a cover and I know I have metal check valves... mmm...

This engine has 3 pumps..... 2 water pumps and 1 vacuum pump.
The 2 water pumps can be used to pump cooling water through the condenser and pump the condensed water back into the boiler. The vacuum pump will help maintain the vacuum in the condenser and exhaust plumbing.


I once had an Elliot Bay Triple (weighs about 400 lbs) that would run at a tick over on 6 psi air.
With my large shop vac plugged into the exhaust, It would run the same on 5 psi.


You could replicate this with a home vac on any model steam engine set up. Just remember to do it for short runs because the vacuum cleaner depends on massive air flow volume for cooling and the motor will overheat quickly if left on too long with most of the flow blocked.

After a few hours run time with the new piston at the Yankee Steam Up at the New England Wireless & Steam Museum in Rhode Island, it is running much better yet.


Will now go in both directions on 9-11 psi..!!


Gil

Making great progress