Thenkt to Mike Clark for telling us about the flickr.com website, here is a pocture of the offside crosshead con rod and crank of the orignal engine from Stanley 7644 before rebuilding. Tou can see the trough for the crosshead roller.

[photos1.flickr.com]

Thanks to you both for your pictures and info. All I have to do now is to decide is it better to roll or ball !! Obviously Stanley prefered to have a roller if they fitted that to later models......

Some of the Stanley parts books list the ball sizes used in current and earlier cars. Check the Steam Auto. Club of America Storeroom page for availibility of reprints.

David, thanks for your info. but I should say that because my engine is not an original, only a reproduction, I am not concerned with total originality. I am only concerned with what is best for smooth running and wear reduction. As a railway locomotive man I am quite concerned with the design of the Stanley crosshead. It only takes the vertical component loads of the connecting rod at the expense of the gland bush! With one ball or roller above and below the crosshead it has freedom to be where it pleases and probably is never where it is needed...and even if it is at the thrust point, the piston rod is used as a lever to take the tilting action of the x-head.

Regards,
Jack.