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L1 project
Posted: Tue Feb 07, 2012 4:57 pm
by Solario
There is a new project to build an L1. Good luck to them! I hope that they are able to correct some of the known design flaws.
http://www.l1-locomotivegroup.co.uk/default.html
Re: L1 project
Posted: Tue Feb 07, 2012 5:02 pm
by 52A
Should be a V3!
Re: L1 project
Posted: Tue Feb 07, 2012 6:21 pm
by v3man
I'll go along with the V3 idea!
Re: L1 project
Posted: Tue Feb 07, 2012 8:52 pm
by manna
G'Day Gents
I agree an V3 would be great, but a L1's not a bad idea for a preserved line, they won't get to go fast enough to shake themselves to bits
manna
Re: L1 project
Posted: Tue Feb 07, 2012 9:21 pm
by Greedy Boards
Agree about the L1, as there could also be a Spanish connection known as El Juan!
Apologies to All
Greedy Boards
Re: L1 project
Posted: Wed Feb 08, 2012 1:01 am
by Hatfield Shed
Solario wrote:... I hope that they are able to correct some of the known design flaws.
Produce an L1/2? There's a lot of redesign to do. Bill Harvey's well known summary doesn't need repetition, but what he wrote, coupled with the likely duty of such a loco on a preservation railway would suggest to me four major points of attack.
Increase bearing surface size in driving axleboxes, or go roller bearing.
Reduce cylinder diameter between one and two inches (the reduced starting tractive effort of no significance for a loco which will not be assigned freight workings, reduces load on driving axleboxes.)
Use proven LNER three bar slidebar.
Side tanks: revise construction design to eliminate weld failures causing leaks, reduce capacity circa 20% to save weight as the range requirement will be smaller, allows redistribution of weight to axleboxes.
Or indeed, build a V3...
Re: L1 project
Posted: Wed Feb 08, 2012 11:06 am
by 52D
V1/V3 please.
Re: L1 project
Posted: Wed Feb 08, 2012 3:40 pm
by Trafford Park
I saw the Gorton L1's in their last days before they were transferred away. They used to work the Harwich-Liverpool boat train and other expresses on the few miles between Guide Bridge and Manchester Central. The DMUs had displaced them on the Hayfield and Macclesfield branches. The loco would be a useful tool to heritage lines particularly with the suggested mods by other contributors. The small driving wheels could be handy for hilly routes. I fancy seeing it blasting up to Calden Low.
Re: L1 project
Posted: Wed Feb 08, 2012 7:31 pm
by Bryan
Hatfield Shed wrote:Solario wrote:... I hope that they are able to correct some of the known design flaws.
Produce an L1/2? There's a lot of redesign to do.
Side tanks: revise construction design to eliminate weld failures causing leaks, reduce capacity circa 20% to save weight as the range requirement will be smaller, allows redistribution of weight to axleboxes.
With regard to the above.
On a line like the NYMR water capacity on locos is an issue especially with tank locos so reducing capacity would be a serious issue here.
The problem is fitting in watering within the current timetable and mileage that the locos are working.
Re: L1 project
Posted: Wed Feb 08, 2012 9:55 pm
by bricam5
If an L1 were built ( nice dream) I would hope that the injector bore at the firemans side would be reduced.
For such an engine to work on the NYMR it would have to be fired against the injector for much of the time.
I found it very difficult to fire against the injector on long or uphill runs without dropping the firehole door flap. A practice much frowned upon in the NE region.
Anauxillary exhaust steam valve would be useless on a two cylinder engine loco.
Re: L1 project
Posted: Thu Feb 09, 2012 12:56 pm
by Hatfield Shed
Bryan wrote:
With regard to:"reduce tank capacity circa 20% to save weight as the range requirement will be smaller, allows redistribution of weight to axleboxes"
On a line like the NYMR water capacity on locos is an issue especially with tank locos so reducing capacity would be a serious issue here.
The problem is fitting in watering within the current timetable and mileage that the locos are working.
This is a good detail design question, of the sort which an established steam D.O. would have no trouble working out, but which poses a greater challenge to the reduced experience available today.
My question would be how whatever of the LMS and BR 2-6-4T 4MTT types with 2,000 gallon tank capacity fare on the NYMR? If memory serves the L1 had 2,600 gallon tank capacity, yet based on comparitive performance of locos of Doncaster and Crewe design is likely to have had no worse, and actually probably better, water consumption figures. Thus the suggestion that some of the tank capacity could be lost for the saved weight (both tank structure and less water) to be redistributed into metal elsewhere: to provide more driving axle bearing surface in particular.
The real defect of the design in my opinion was Thompson's ambition to have it excel in everything that could be expected of a class 4 locomotive, instead of making it more specialist: a reasonably fast unit for use on main line stopping and semi-fast passenger service, which was the duty it was really required for. To make it suitable for heavier freight work on lines with low RA it required a higher starting TE, and the additional tank capacity to give it endurance for out of course stops waiting on faster traffic, while still remaining light for a low RA rating. The weight was contained by a lighter chassis construction, and there was where the mechanical trouble started, especially given the relatively high piston loading and the faster rotational rate required by the smaller than usual driving wheels. All compromises directed at a class of work which it generally wasn't employed on...