My 3 x 5 victorian twin steam engine restoration is plodding on, but have come across yet another stumbling block when trying to assemble everything. Due to subtle internal dimesional differences in the two cylinders, (which I should have accounted for but missed!) I found that one conn rod is now a matter of about 4mm too long between bearing centres!

I can't just re-bore the little end in the new position as that would leave no bearing material at the front. I don't think I can just bore a bigger hole for an oversized pice of PB and re-bore as that would leave little steel support top & bottom. One thought was to sweat in a piece of steel to replace the current PB bearing, then re-bore in the new location for a bearing, But am unsure if this would work.

It was a huge job making these conn rods out of solid, so have no desire to repeat the exercise! Any suggestion please?

Dimensions: (mm) overall 250, little end bearing 22 od x 15 bore. 15 deep.

Thanks for the feedback guys.

JasonB – The piston rod and part of the crosshead are a one-piece forging. I have been trying to retain as much of the original parts as possible, and I've already had to modify the ends where they attach to the pistons as those were completely ruined and had to be re-made, but due to severe wear and missing material I had to modify the connections into the piston which now leaves no room for further change. I do take on board your comments about positioning though.

Ian, Had considered this, but my concern here would be re-aligning things after joining as there wouldn't be any room for error as both ends are abviously currently in line, and the tinyest error would stop the smooth running of the mechanism.

Howard / mart. : I'll have a look at how feasible that idea is. Cheers

regards to all.