An NSR Absolute Block instrument

I made a short video last night. I didnt narrate it as I was still unsure what some parts are called, but it gives you some idea as to how it works.

https://youtube.com/shorts/jLM3UjJj3LE (for some reason I cant embed a short video)

 

ah, well I didn’t know it was that short when I filmed it. Felt much longer..
I will look to last longer next time…

 

I spent half hour today trying to get the bell to work..

Peter gave me some new diagrams for wiring ready for when we get the simulator, and I will need to make some modifications. It be a small terminal block like those fitted.
I’m expecting this in the post soon (I hope)

it’s to change where one wire from one of the coil goes to. Peter kindly highlighted it approximately for me on this old photo of my instrument, which actually shows how far we came.. oh dear. I forget just how bad it was and how far I’ve come!

Anyway, back to the drawings…

this will be the approximation I’ll be working from, and I need to now look at all those wire labels I did back when I first took it apart.. and relabel them! they have different letters here so it would make sense to amend it to match.

I’m focusing on the bell section at the moment, and this shows the + and - feeds as well as the R1 and R2 feeds.

First off I took out the volt meter to check the resistance.

latch resistance
Striker coil resistance

and finally, wiring in.

im missing something as the striker will only work when the blade over the right hand coils is triggered. (This breaks the contact to the hammer striker coils) but I have had the hammer one moving! We did get a video, but it’s too short to add.

 

I have now had the final wiring draft from Peter and the full wire up has begun, including making proper terminals (wires soldered on to M5 brass washers) but only at the moment on one end due to having to split it all down to finish the back board. The new terminal block has been installed.

I have around 3 wires left to add and then we are almost ready to go. I'm not sure what will and what wont work just yet till the next part of the simulator arrives


The keen eyed will notice that terminal M has been added since the diagram I posted previously.

 

We have had success ! after a little hiccup... I didn't realise the Earth doesn't go to the neg battery terminal (or the Neg feed on an old H&M clipper controller).
At first all I could get was line clear, but due to the change in wiring I had totally overlooked (or wasnt informed) that with no simulator yet, that L1 needed to be set to Earth to make the lower half work - The upper dials wont work till the simulator is connected as of course, the upper dial is what is sent from the neighbouring box. It also means that the bell wont be ringing for a while as L1 to a + feed will make it strike, but as this is now to Earth, I'm simply left with the lower gauge matching the commutator.

I'm trying to add a video, but sadly its only around 30 seconds -I'm going to see if I can extend it to make it long enough (even if its adding photos to pad it out) so you can all see it working.



the only down side is, the silly editing program on my phone only does landscape and guess who filmed it in portrait! The video starts with me testing the bell, then testing the wires earlier today and having issues before Peter told me about the L1 to Earth setting
Andy

 

When you created yours I dont think I had even purchased mine, so I would have no idea how complex it was. Yours were a work of art..

I have considered making some for my layout but cant justify the need for how my layout currently is. I found some 3 position rotary switches on ebay and also a 15v meter that had a centre off (so swung between minus 15v and +15v) which would have been easy to just swap polarity with the rotary switch as it was effectively a DPDT centre off.

Its on my to do list and comes in at around £20 a box. However I would need to think out the bell and I doubt id have any latching like the real thing !

 

Don’t forget I have the originals for Leek Yard now. I hope to frame them one day.

if Leek station diorama goes on display, they would be perfect to display along side.

 

As I was having a day with my mate Martin doing some work on my other interest, the PAA sand hoppers, I decided to take the block instrument and take 5 mins with it in the newly refurbished Cheddleton Crossing signal box. A genuine NSR box with a restored (almost) NSR block..


after spending the day changing buffers and shunting about to get access to said wagons, pulling stuck fork lifts out of ballast and then putting it away, it was time to take the lock to the box.


Roger was our shunt loco. It’s hard to actually imagine that it’s 70 years old next year. Built in Sheffield by Yorkshire in 1956 is a Janus loco, but only working on one engine at the moment due to a traction motor fault.

we now have two of these wagons in our custody. This is the complete one. The second one we were changing buffers on (when collected from Robert’s Road in Doncaster it had had a set removed as it was basically the “Peter” to pay Paul Wagon and had become a donor of spares, of which a pair of buffers and draw hook were among the larger parts) as when it was first moved we had to fit a smaller diameter pair to make it safe to move. More of this on another topic anyway as I’m digressing…

When we finally got in the door, I could only place it on the cupboard as the block shelf fitted in this box is a later LMS style which hangs from the roof timbers. The block would also have sat at the back of the box over the frame (which also was rearward facing) unlike many of the other models I’ve done where the frames were at the front window and the whole block shelf secured to the window uprights.

Martin and I discussed that as this was a fair weight
That two of these having on two timbers a good foot away from the upright window timbers must have been a huge strain on the structure and needed some very good securing.

I was asked by the former NSR chairman if I could leave it! I politely declined as there is still work to do. However, the idea is for it to return and hopefully next time it will be Leek Brook Junction of which it’s the signal box from which the block is replicating..

what we need is another one! (No not for me!)

 

There is some work going on in the background. But not really much to tell on here just yet. It’s mainly the cutting wood side and routering. So once I’ve got a little further I’ll bring some more photos to the table.

 

Thanks Paul,

When I come up, It will come with me for inspection..

Andy

 

Things have been a little on the quiet side on the block instrument for a while, although I have been in regular contact with another guy called Sean who is trying to get two units serviceable for two signal boxes in Cumbria.

sadly, he is missing a vital component, the electrical contact selector on the back of the lower door.

here is Shaun’s bloc instrument, which has some funny metal “thing” inside which serves no purpose what so ever.

I looked at mine, took it apart and sat and looked again to see if I could replicate this.


this is how it should look.

I therefore again turned to the 3d drawing app and sketched it out.


It’s made up of a 10mm Bakelite base and 2mm copper track work with a brass pin.

here is the copper tracking on its own.



Yesterday I printed the disc. I set it on a slow setting after I had done a software update on the printer (related to a computer update and finding the printer no longer liked the files !)
17 hrs later and here we go. 67mm disk base.

and from the other side



a comparison with the original. Of note, we seem to have seen two versions of the disc, one with copper tracking (like mine) and also with brass. Although we can’t find any reason as yet why?

and finally a test fit.

I have ordered some 2mm copper PCB. It’s a push to make contact not moving so very little wear. But, I need to see if I can find someone with a lazer cutter to slice the PCB parts to fit.
More later

Andy