Greg,
The engine and boiler was sold to a chap in Austria and I believe it is steaming up and down a lake outside Vienna.
Back to your Yarrow boiler.
Mark off a center line in your mud drums and mark of the holes as per sketch.
I use a set of draughtsmans small dividers which mark the copper very clearly and center dab all the holes, same for the top drum with the line set out to match the angle of the down tubes.
I didn't flatten the mud drums as K.N.H. I drilled them out on the Mill/drill and after drilling ran a 5/16" dia drill fixed in the hand drill and opened them out so that the tubes went in straight, do the same with the top drum.
Set up the tubes in the top drum but keep them lying horizontal and supported as you braze them other wise the weight of the tubes if held vertical will distort the top drum, do the same with the other side not forgetting to use the steel jig to hold the tubes in position in the holes.
When cool slide the jig to the bottom for the mud drums as you pull it off it will bring the tubes into approx line and then you can fiddle them into the holes and braze up. EASY PEASY.
I am sending you a sketch of hole markings but if it doesn't come out let me know and I will P.M. you the sketch, any further help please ask.
I was down your way 21-07-10 and visited Conniston and D.Campbells grave, I stood at the lake side in peeing rain and in the silence I could imagine the roar of the Bluebirds Engine.
As an aside from steam I have just built a 1/12 scale model of K7 with brushless motor and high power battery and it's going at 27 mph which is just over 300mph to scale.
We came down from Conniston to Torver and then down the A5084 to Penny Bridge and passed a little spot where the road touches the lake side with a couple of parking spots, my ambition is to one day bring K7 and sail it on Conniston at this spot.
I have listed K7 on ANY OTHER BUILDS on a thread by BISCUIT, if you would like a very grainy movie let me know and I will post it via P.M.
George.
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