# NER EE-1 Nightmare with mousetraps...



## ralphbrades (Jan 3, 2008)

The reason I have not been posting updates here has to do with planning problems -I can either model -or I can get the garden ready for the track work. Given the latitudes I live in, mean that in the long summer evening I can dig until 9:30 !!! 

The main progress has been with the "mousetrap" bar assembly -this captures the rear bogie arm and holds it rigid while the loco is moving in straight line. The front bogie is free to move and the mousetrap bar is held "up" by the fwd/rev relay (which also feeds the lights!)


This shot shows the mousetrap bar with the bogie arm trapped by the slot cut into it. (The magnet has been CA'ed to the end of the bogie arm












This shot shows the bogie arm to one side -the slot can be seen quite clearly.











This shot shows that the reed switch has been fitted (simply stuck to some offcuts of 5mm sq pine) and the magnet sit normally below the reed. When the magnet moves away from the reed the circuit opens and the bar drops. Once the loco has returned to the straight the slot captures the bogie arm and the system resets.











The last two shots show the loco with the body fitted -looking very "purposeful" in its grey primer I feel!!!





















The next things to build are the three gearboxes -then my nightmare will have teeth -*936* of them to be precise!!! 


regards

ralph


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## Havoc (Jan 2, 2008)

I don't see it Ralph... 

The front bogie is free to move and the mousetrap bar is held "up" by the fwd/rev relay (which also feeds the lights!) 

When your driving forward, the bar of the front bogie is raised so the bogie is free to turn. The bar is lifted by the relay. Fine so far. By assumption, the bar of the rear bogie if lowered (by the spring I see at the left) and once it gets trapped in the slot it stays there. This I can follow. 

This shot shows that the reed switch has been fitted (simply stuck to some offcuts of 5mm sq pine) and the magnet sit normally below the reed. When the magnet moves away from the reed the circuit opens and the bar drops. Once the loco has returned to the straight the slot captures the bogie arm and the system resets. 

Here you lost me. The bar is raised, the bogie moves, the reed switch cuts the current to the magnet and the bar falls. So when the bogie returns to straight the slot catches the bogie and holds it. The cycle you mention -I assume- is that at that position the reed closes and activates the magnet that raises the bar. But then the bogie is again free to move! So why that cycle if the result is that the bogie is again free to move? Can you just keep the bar raised? You are talking about the front bogie? 

The loc does look purposeful indeed. Quite a sight. Time to put those wheels under it.


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## Torby (Jan 2, 2008)

Just remember, "The *second *mouse gets the cheese."


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## ralphbrades (Jan 3, 2008)

The front mousetrap bar is lifted -thus the bogie is free to move. The front bogie arm is fitted with a QTC compression sensor -this detects when the arm had moved from the straight position. The relay that fires the solenoid that lifts the rear mousetrap arm is fed from this front sensor -the system is reversible. 











When the rear bogie arm moves it opens the reed -which has the earth connection for that relay. Thus the solenoid drops and the system resets once the rear bogie arm moves onto a straight section of track












regards


ralph


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## Havoc (Jan 2, 2008)

OK, I get it now. Your description is of the rear bogie that is fixed but released in the bends (by the sensor at the front) and then catched again after the turn. Following again Ralph, go ahead.


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## Les (Feb 11, 2008)

Simply awesome.

I'm patiently awaiting the gearbox build.


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## Les (Feb 11, 2008)

It was only after I was in bed that the following thought occurred to me: "Why would one want to lock down the trailing bogie on straightaways?" I can think of a couple of possible reasons, but a failure to release--wouldn't that induce a major problem?


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## Robbie Hanson (Jan 4, 2008)

Les, I believe this loco has a single middle power truck. Without a locked bogey on one end, it could therefore swing rather widely side to side on a straight section of track.


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## Les (Feb 11, 2008)

Posted By Robbie Hanson on 13 Jul 2009 01:55 PM 
Les, I believe this loco has a single middle power truck. Without a locked bogey on one end, it could therefore swing rather widely side to side on a straight section of track. 







Robbie, I thought it had a pair of driver trucks. My bust. Were it not a model, I'd wonder about a failsafe. (In the real ones.) With a single driver, I imagine it could easily become longitudinally unstable. Nevertheless, it's a fantastic project and I wish Ralph every success.


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## ralphbrades (Jan 3, 2008)

Les,

The loco is a 2-C0-2 design (or 4-6-4). The rear bogie locking is as the original -except Sir Vincent Raven used compressed air rather than a spring solenoid system. At high speed (over 50MPH) the front bogie was also locked -this made the loco a very rigid structure. You can see the three slots in the chassis frame for the horn guides for the 3 driving axles in the centre of the loco. The driving wheels on the loco were 6 feet 8 inches and it was designed to pull 8 carriages on the 1:87 inclines on the York to Newcastle section of the East Coast Mainline.


The build diary for the loco can be found here: http://www.cabbagepatchrailway.co.uk/neree1.html 


Happy Reading!

regards


ralph


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## Les (Feb 11, 2008)

Holy cow! Six foot drivers? What was the designed running speed on that thing, about 90 mph?


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