Traction Engine Cylinder Pattern

[Jo]

Ok guys this one has been annoying me.. How do I put together a pattern for a Fowler compound cylinder?

I have found some pictures of one and there is clearly a join mark down the side of the cylinder but then there is that curved flange underneath that goes the other way and yes the valve chest has been cut off the top and rejoined but it looks like it was part of the same casting originally.. and that adds another flange at the top to prevent the pattern coming out of the sand 

I have seen pictures of patterns for full sized Fowler cylinders but they don't give a clue as to the make up or splits for packing the sand for casting. Anyone any ideas?

Jo

[Jasonb]

Jo have you looked at the Fowler Tiger thread on TT, He has posted some pictures of the cylinder pattern there and Edward has some of the GMT cylinder

http://www.littlesamson.co.uk/gmcylinderpics.html

I'll dig out my Superba one and if you are good I'll bring it over with me. You could ask Alan for a look at the A7 compound cyl pattern that goes on the road loco.

J

[Jasonb]

Right had a think and the best way would be to split the pattern at right angles to the boiler and make the pattern as if there were no lagging recesses in the sides but add a big coreprint. Also add a couple of round coreprints for the two cylinders. If you also wanted you could do ones for the valve chest and recess under the cylinder and even link them with passages to get the steam up to teh regulator

Then make a pair of cores to form the lagging recesses.