P2 Locomotive Company and related matters

A very powerful sales aid is being able to say, here's one we made earlier. They also have a very good professional fund raiser in Mark Allatt.

 

Of course you know/remember the old saying......"Success breeds Success!" Having produced Tornado [ is she really 10 years old this year.....], no matter the design, they were pretty well guaranteed success with their new machine. Let's face it they've already started acquired parts for the next locomotive the V4.

 

Amazing progress! This is a huge achievement for the trust. This is all starting to become very tangible!

Think I asked already, but is there any plans for an open day once the wheels are under her?
Tempting to ask if anyone from the office would be keen to go for a look if so...

16 Coaches? More?

 

I reckon the P2 could handle 16 on its own.

They have an open day at the works every 4th Saturday. not sure if it's for members only.

 

Honestly, given the stick Tornado is getting in the railway press from some individuals who should know better (and are doing so purely to rock the boat - make no mistake) I can forsee people getting angtsy about 9 coaches at this rate of varying vintages...!

No really, I just hope we are allowed to enjoy the P2 developments and its tests thereafter. Steam for the future in a measured and compliant way.

 

This is wonderful. It put me in mind of the late, dear Jonathan Minns, who was a true, passionate evangelist for British Engineering. The scale of this project, plus the fact that it is being fronted by a young woman, would have had him whooping with joy! I hope he's up there watching.

 

I would also like to give my biggest thanks to the inventors of the wheel in the late Neolitic period 200o - 4500 BC!

Knut

 

You could also add thanks to the discoverer of fire.

 

Wasn't that Mazda, who stole the secret from the gods? Or did he invent the light bulb?

Sorry, getting silly now!

 

I know he couldn't make radio valves or television tubes for toffee...



In fact, some in the world of TV used to sing "Mazda tubes stay softer longer"...

 

Just looking at the photos of the Driving Wheels, it looks like there are no balance weights. On the originals, were these cast as part of the wheels? Or were they built-up and rivetted with snap-head countersunk rivets? Interested to know, and haven't got my P2 books to hand at the moment!

Richard.

 

I'm not sure about the original locos, but the drivers on 2007 will be balanced by fixing plates to both sides of the spokes and pouring molten metal into the void between them. They've come up with a calculation to determine exactly how much molten material is needed for each wheel and its precise location. I think this is considered more accurate than casting balance weights into the wheels and then drilling bits out until balance is achieved. I think they did the latter with Tornado.

 

"For No. 2007 we are intending to achieve balancing entirely by calculation and by using built up balance weights (crescent shaped plates riveted on both sides of the spokes with predetermined quantities of molten lead/antimony alloy poured into the cavities between the spokes and plates). This was standard GWR/LMS/BR practice. However instead of using a dynamic balancing machine to determine the precise amount of lead required, we intend to do this by calculation. The starting point is the centre of mass of the wheels. The 3D CAD models will predict where this is, however as the wheels are castings which rarely turn out precisely to the shape of the drawing, we need to use other methods to determine the centre of mass. One is to 3D scan the wheels to produce a solid model from which Solidworks 3D CAD can compute the centre of mass. To back this up we will also determine the centre of mass of each wheel in the plane of the wheel by balancing it on a knife edge on the back of the wheel boss and repeating this with the knife edge at 90 degrees."

https://www.p2steam.com/2016/10/31/getting-balance-right/

Its a good way of doing it, and if you are using 3D parametric modelling, its the obvious way of doing it.
The center of mass can be pulled in a couple of mouse clicks, accurate down to a tens of millionths of a gram, something the original designers could have only dreamed of!

 

Do you intend to add any balance for the reciprocating masses or depend entirely on the semi-self balancing of the three cylinder layout?

 

"As all the other components (tyres, crank pins, coupling and connecting rods, pistons, piston rods and crossheads) are fully machined to close tolerances, their masses and centre of masses can be computed accurately, as can any material removed from the wheel centres during tyre and crank pin fitting, the existing surfaces in these areas being already machined. This removed metal will cause the centre of mass to move slightly, but this displacement can be accurately calculated. The final check on hammerblow (the minimising of which is what balancing is all about) using the ‘Wheelchex’ equipment during the main line testing."

That reads as a no to your question, but again, its easy enough to balance the whole rotating machine on the computer, and so be well informed of where and how much correction is required.

One wonders if the Wheelchex bit is just validation work rather than remediation...

I speculate, but I would imagine NR are driving the P2 group on getting the least possible hammer blow in to this machine as practicable. Im sure we would all agree that its in everyone interests that she is as smooth as possible out on the road.

 

The description of the balancing procedure mentions various components including "pistons, piston rods and crossheads". Those are purely reciprocating masses, so are irrelevant if only the rotating masses are to be balanced. So that does suggest some balancing of reciprocating masses.

 

Aha! I knew I'd read something on their site before, but I couldn't quite remember where... Must be the heat jellifying my brain! Thank you for the link, much appreciated.

Richard.

 

That's nothing, I though they had only posted it a few weeks ago...it was in 2016!
Not at all

 

Mandy Grant of the A1 and P2 Trusts has shared some photographs online of Tornados 10th birthday party at Darlington works. These also show the P2 on its driving wheelsets and cartazzi set. Pony truck to follow she reports.

https://www.facebook.com/groups/3034685719/permalink/10160758710700720/



I was having a fairly bad day until I saw the pics, this has cheered me up no end. What an achievement and another big milestone.

 

They only arrived a couple of days ago! They don't hang about, do they?