Lancaster Bomb Switch Panel

[dr_gn]

Currently building a model railway for the boy & his Grandad (in other words, me). I'd suggested buying a load of switches and mounting them on a board to operate the points, when my Dad said he'd already bought some "just in case" back in the 1940's from a war surplus shop. Turns out they are bomb selector/arming switches from a Lancaster:





Perfect - beautiful bit of work, but somehow I hope this particular unit wasn't used in anger.

[dr_gn]

Simpo Two said:

Lots of switches there. If I was a Lancaster bomb-aimer I'd just have one switch labelled 'THE LOT'

Apparently....

The switches arm the bombs rather than drop them. When a switch is pressed, it operates a clamp in the bomb bay which grips a wire connected to the individual bomb fuse. Then when the bomb drops, the wire pulls a pin out and away it goes. If the wire isn't clamped, the pin goes with the bomb and in theroy it doesn't explode.

You can select a range of drop patterns with the rotary switch/window, and select individual bombs with the switches. If you remove the jettison clip and push the bakelite bars to the left, the whole lot goes without being armed.

Normally though, after arming with this panel, there's a thumb trigger on a flexible lead that the bomb aimer presses over the target, and that single switch lets whatever bombs/patterns go.

http://jproc.ca/rrp/rrp3/lanc_10mr_armament.html



A really shabby one sold for £250 at auction last year. Didn't think it would be worth that much: would pay for the model railway!

[dr_gn]

perdu said:

There's a definiite "thumb" mark on one of those switches

I'd better look after it for you

(will it do the job for you? If so fill yer boots)

It'll easily do the job - The case is very nice thick aluminium, the external screws are perfectly countersunk and the the switch mechanisms themselves are beautifully engineered. The rotary selector mechanism is a work of art!

Somewhow I don't think the Maplins switches would last quite as long.

[dr_gn]

deadtom said:

Marty63 said:

Would it be monetary valued more if it had been used in anger ??

i got the impression it was more that the OP wouldnt be comfortable making a play thing from a device that has been used to kill (innocent?) people

Exactly. I've seen it kicking around at home over the years, but it never really dawned on me until yesterday that it might, just might, have played a part in killing - as you say - innocent people. Then again it might not. At the end of the day it's just a box of switches. If it ends up getting used as part of a toy railway, so be it: at least it'll be used for something constructive.

[dr_gn]

mybrainhurts said:

Or you could pretend to bomb the railway with it...

I could, becasue I can't figure out how to wire the points switches!

I need an impulse (via. a capacitor discharge unit) to fire the points one way or the other. If I use a normal two way switch, it'll burn the point solenoid out. If I use a centre-return two way switch, I don't have a way of knowing where the points are, well, pointing. I could use a two way switch to select the direction, and a push to make switch to fire the points, but I dunno...I thought it would be easier than this!

[dr_gn]

jaybirduk said:

Very nice, I hope you manage to get working while retaining the integrity of the device.

Thanks, I wouldn't consider altering it an any way - there are screw terminals ready to connect all external wires to.

[dr_gn]

Simpo Two said:

deadtom said:

i got the impression it was more that the OP wouldnt be comfortable making a play thing from a device that has been used to kill (innocent?) people

It's called provenance, and had they not been used you might well not be around to post such naive drivel.

I don't think he was being naive: the civilian cost of strategic bombing was a fact, no matter how horrific. I'm not particularly criticising the need to do it, and certainly not the people who carried it out.

My comment was really that this is a piece of equipment that *potentially* played a key part in melting women and children into tarmac streets, and it's not a particularly nice thought for any sane person.

On the other hand, it's just a box of switches. I wouldn't go out and buy one, but my Dad bought it for his model railway 65 years ago. I doubt he's ever given it a second thought, and maybe I shouldn't have either - after all, as a young child my Dad was on the recieving end of the Luftwaffe many times during the Sheffield Blitz. As he says..."Happy days"!

[dr_gn]

Eric Mc said:

Which switch is for the Cookie?

The one marked "BISCUIT" on the selector.

[dr_gn]

Simpo Two said:

dr_gn said:

My comment was really that this is a piece of equipment that *potentially* played a key part in melting women and children into tarmac streets, and it's not a particularly nice thought for any sane person.

The dying civilians thing is a post-war distraction that achieves nothing other than pointless self-flagellation. Which is something we seem to be very good at these days.

I'll better tell my Dad never to mention the terrors of an air-raid again then

As far as I'm concerend, it doesn't matter which side was on the recieveing end, or even "who started it". When we're talking about civilians being killed in a war it's a tragedy, full stop. Maybe necessary, maybe not, but still a tragedy.

[dr_gn]

Turns out it's not much use for switching points after all. I need a pulse rather than a continuous current.

I guess it will be put back in in the loft.

[dr_gn]

Hooli said:

dr_gn said:

Turns out it's not much use for switching points after all. I need a pulse rather than a continuous current.

I guess it will be put back in in the loft.

How about charging some capacitors then using the switch panel to 'fire' them? My very limited knowledge says that the caps charge while power is going to them & 'fire' when the current is stopped.

Yes, you use a capacitor discharge unit to give the points solenoids a kick, but it's the residual current that burns the solenoids out.

The simplest way (but unbelievably expensive) is to buy some "passing contact" switches. They toggle up and down, but on their way to fully up or fully down, they pass a contact, momentarily making the circuit, then are insulated when the swith is fully toggled. This way you get a visuial indication of the state of the switch, but with no residual current.

You can buy a normal toggle switch for 50p, but passing contact switched are about £4, and I need 10. This railway is getting expensive!

[dr_gn]

Zaxxon said:

I'm surprised by the way this thread has gone.

Yes it has probably been used for what it was intended. Good, that makes it more special.

Using something that a collector would cherish as a toy? Just wrong.

I knew exactly what would happen the moment I wrote:

"...but somehow I hope this particular unit wasn't used in anger."

Predictable.

[dr_gn]

Somewhatfoolish said:

What is the rotating selector actually selecting? What's container/distributor/etc?

From notes from a random forum:

1. Safe Except for Jettison - with this setting bombs cannot be dropped by any operation of the selector or firing switches

2. Single and Salvo - with this setting the Distributor Unit is short circuited and bombs are released by selector and firing switches

3. Distributor - with this setting the Distributor is in the circuit and operation of the Firing Switch starts the arm of the Distributor moving which drops the bombs. The Carriers must be selected.

4. Container: As above but the contacts on the Distributor are joined together.

At the other end of the box are two Jettison Bars. By pushing these bars in, the load is Jettisoned irrespective of the setting of the Drum Switch.

[dr_gn]

Yertis said:

Dad used proper H & M point switches when he wired up my railway 40-odd years ago. It was like watching him practise magic. But couldn't you use a toggle switch to flip the polarity, then a push button to briefly energise the circuit?

Probably much easier to cough up for the proper switches...

You could, but if you flipped the switch without pressing the button (for whatever reason) you wouldn't have a positive indication of where the points were.

dave-the-diver said:

This is based on memories from at least 35 years ago, so be gentle!

I drew a track diagram onto a bit of board, then put a pair of brass panel pins through the relevant tracks behind each set of points.

Soldered wires onto the back pins (probably actually soldered the wired on first then passed the wired through a pre-drilled hole, but you get the idea).

Wired the common of the points solenoids to -ve, the other side of the solenoids to the pins, then had a permanently live flying lead (+ve), which could be touched onto any of the pins on the track diagram to fire the points.

Simple cheap and easy.

David

Peco do the parts to make a system like that, but again, there is no idication of how the points are set, which is what I'm after.

Thanks for the ideas though.