Mallard vs Flying Scotsman performance
Good Morning!
As you can also read in my "scientific approach" post, I recently had the chance to get hands on a Flying Scotsman in very good condition for a reasonable price. Of course the loco will also be included in my testrun program.
Here are some questions about the Scotsman from the first steamings:
- The Boiler in the Tender is engraved with a number. Is this normal for the A3s? My Mallard does not have this.
- The A3 seems to be much more responsive an controllable then the A4. The acceleration and slow speed performance are so much better. Is this typical for the A3 model with their smaller cylinder volume or does it show a different status of cylinder seals? I do not think both locos had a lot of steamings before and most likely had no exchange of the cylinder seals. Mallard is from mid 2004, Scotsman from end 2005.
- Also the reverse performace is so good, that you can couple to a standing train without spilling all drinks in the restaurant car. Impossible with my A4, which is completely uncontrollable when starting in reverse without a load.
Looking forward to your thoughs
Martin
Boiler numbers first:
The very early Mallards didn't have a boiler number. I'm not sure when they did start numbering the A4s, but the club roadshow has a Seagull with number 10252, which is the highest boiler number I have seen. The A3s all have boiler numbers starting A3_xxxx. Not sure what the highest A3 boiler number is, probably somewhere between 4000 and 5000.
The difference in performance will be down to the timing settings (different adjustment screws for forwards and reverse) and the state of the seals or other tiny steam leaks. One turn of the timing adjustment screws can make a big difference in performance - adjust them to get the performance you require (slow speed controllability vs high speed power). Sounds like your A3 is better adjusted than the A4, but there's no reason why you can't get the A4 to be as good as the A3.
David