J611 chuff rates

Four chuffs per one revolution of the drive wheels is prototypical. It's constant across the entire speed range. 

Lou1985 posted:

Four chuffs per one revolution of the drive wheels is prototypical. It's constant across the entire speed range. 

Thanks, will see what the J chuff is set to.

Now that is four chuffs per wheel revolution on one side but other side is quartered ahead/behind, so in reality, wouldn't someone hear 8 chuffs total by time both wheels completed their revolution circuits?

There are only two chuffs for each cylinder for a driver rotation, so the other two chuffs come from the other side.  Thus a non-articulated steamer with two cylinders would have a total of four chuffs for the driver rotation, one at each quarter rotation.

Check this video for operation of a typical locomotive steam engine, the useful stuff starts past the 2 minute mark.

rrman posted:

Lou1985 posted:

Four chuffs per one revolution of the drive wheels is prototypical. It's constant across the entire speed range. 

Thanks, will see what the J chuff is set to.

Now that is four chuffs per wheel revolution on one side but other side is quartered ahead/behind, so in reality, wouldn't someone hear 8 chuffs total by time both wheels completed their revolution circuits?

No. All two cylinder steam locomotives have 4 chuffs per driver revolution, i.e. 2 chuffs on each side, with chuffs happening every 90 degrees of rotation. No ifs, ands, or buts!

A 2-cylinder steam locomotive = 4 exhausts per revolution of the drive wheels.

A 3-cylinder steam locomotive = 6 exhausts per revolution of the drive wheels.

N&W 611 is a 2-cylinder steam engine.

A locomotive steam engine is a "Double Acting Engine" meaning that the piston is pushed BOTH WAYS as  it moves back and forth in the cylinder. Because it has one power stroke in each direction, it also has one exhaust stroke in each direction.

Rich Melvin posted:

A 2-cylinder steam locomotive = 4 exhausts per revolution of the drive wheels.

A 3-cylinder steam locomotive = 6 exhausts per revolution of the drive wheels.

N&W 611 is a 2-cylinder steam engine.

A locomotive steam engine is a "Double Acting Engine" meaning that the piston is pushed BOTH WAYS as  it moves back and forth in the cylinder. Because it has one power stroke in each direction, it also has one exhaust stroke in each direction.

Got it! Thanks.