Jon Fitness' average 7mm signals workbench.

[Jon Fitness]

Another ex-Talacre signal has been dug out of the cupboard. This will now act as the up&down branch home to either the connecting line (RH) or the main through all the crossings (LH). The top left arm was swapped from a shunt to a full size and the bottom left will be for shunting over the crossings with a view to setting back into the shelf sidings.

This signal used to be operated by memory wire but I found I was constantly having to adjust the stuff and the action wasn't really to my liking. This was all stripped off except for a short length of the wood it was mounted to and a (very ) makeshift frame made for 3 servos, these being fastened on with 10 BA nuts/bolts.

For the sake of simplicity I have fixed the drive rods directly to the horns this time, something I'll probably regret later! ( lack of adjustment etc,



All these have been adjusted for travel and speed on the driver board so in theory, all I have to do is hack a hole in the baseboard and screw the thing down. Once connected they should work without further adjustment.

More to follow..

JF

Edited May 30, 2015 by Jon Fitness

[davec.hh]

Jon,

 

Nice to see the workings and layout of the operating wires. Do you have bounce on your signals programmed in?

 

Hopefully you'll not need to adjust. when I get round to producing my NE signals I'll be following your example with servos, it seems to be the way to go nowadays.

 

Another good looking signal

 

DaveC

[Jon Fitness]

No bounce on these Dave.

The MERG driver boards are progammable to produce bounce if you download a seperate program and use a computer to set them up. I use one of the setting up boxes made from the MERG kits so I can't do it.

Bounce would probably be ok on a single post signal with no linkages but theres probably a bit too much play in my mechanisms for it to work properly .

JF

[Jon Fitness]

The latest re-jigged Ex Talacre signal has now been fitted to the layout after Steve made a little plinth for it to stand on/in. Fortunately the bench work paid off and it worked OK first time without adjustment.

Unfortunately one of the LEDs has since failed (a very rare occurrence) so it may have to be removed for attention. I’ll buzz the wires out first just to see if it’s my usual dodgy soldering!

More soon.

[Jon Fitness]

One for the GW fans now.

I must confess to being more of an upper quadrant fan, but one corner of the layout seems to have a GW flavour signalwise.

Some alterations have taken place to the layout and we now have a bi-directional line that needs a signal for movements from it into a platform and on to the shed.

A bit of a quandary then arose. It’s a passenger line, there’s little room for a bracket and I was looking for a slightly different signal anyway.

I’m not too sure what the GW or BR(W) might have used but I considered

1. RH offset bracket with 1x 4ft arm and 1x 3ft arm

2. RH offset with short bracket and elevated disc

3. Straight post with offset elevated disc.

On the MSE etch for later GW signal arms there is an etch for a “cash register” style route indicator so (not sure if it would be technically right but..) just for variety I’m doing one of those under a standard 4ft arm on a straight post.

First pics show the built up post with finial.

 

The spec plate and blade have been soldered together with a brass 14BA bolt as a pivot. I like to use nuts and bolts so that I can set everything up and then dismantle it for painting.

I like to make sure any lower quadrant signal I build will return to a horizontal danger position so I always fit some sort of arm stop. In this case it’s a short plate on the post and a pin on the signal arm (pardon the scruffy soldering it will be tidied up!)

A long length was soldered on then trimmed down so that it just caught the stop.

(yes I know the finial's not central to the post. It’s wider than the tube and getting it central is a pain! ).

More soon

JF

[Jon Fitness]

Next job is the signal lamp. I’ve drilled out the lamp case (MSE late pattern GW lamp case) to accept a warm white 3mm LED and the small hole below is to accept the negative tag of the LED.
The negative tag (the shorter one) is bent round, fed through the small hole while the LED is fitted loose in the larger hole. A small blob of low-melt solder is then used to secure the tag in the hole. Should the LED ever need changing it is then easy to remove by releasing the tag with a touch on the soldering iron.

This means the whole metal structure of the signal is now the LED’s negative tag!
A mounting bracket was then fabricated from some scrap etch and soldered to the post.

The lamp case was then carefully soldered to the bracket with a little bit of 145deg and checked for alignment.

This is where using a bolt and nut to pivot the signal arm becomes useful as the arm can be fixed in whatever position you need for setting up.

A small hole (about 0.8mm) was then drilled in the back of the post and a length of fine insulated wire fed down leaving about 2” at the bottom of the post and a short length at the top. This was then soldered to the positive tag on the LED and 3v DC applied to test the LED.

All OK at the moment.
So, basic signal built, time for the route indicator gubbins. This is included on the MSE etch for the later pattern GW arms suitable for tubular post signals and is provided with 2 “shutters” although I thing the real thing can have up to 4.
(Scale Signal Supply do a kit for the wooden post version, one of which I have in store for another job!)
This is the etch as snipped from the fret, ready to fold up.

I decided to add a divider from brass section up each inner side of the case. This is to stop the shutters from rubbing and scratching the faces together as they operate.

The case folds up easily, forming its own mounting bracket as it does.

Once soldered up, it was fitted to the post below the signal arm.
I’m not sure about the exact distance it should be from the arm as most pictures I’ve seen seem to vary.

The shutters are moved up and down by operating arms pivoted on the post below the casing. These in turn are linked to the signal arm so which ever shutter is moved, the arm moves with it.
The total movement or sweep of each shutter is about 12-13mm so the operating arm pivot (made from brass tube with an internal diameter suitable for a 14BA bolt to slide through) needs to be soldered on about 15mm below the bottom of the case. I decided to twist the tags on the shutters through 90deg. so that the joint holes matched those in the operating arms. Not strictly as prototype but simpler to link up!

The holes in the etched operating arms and shutters were then opened up to accept the 14BA bolts and fastened (very ) roughly together to check operation. It was then found necessary to crank one of the tags on the shutters to get smooth operation.

This of course had the effect of shortening it so the operating arms now sit at slightly different angles. Hmph!.

At this stage everything waggled loosely as it operated. This wouldn’t help when the linkages were required to work the signal arm later on so..
The BA bolts are steel and the nuts are brass so (hoping that the solder wouldn’t migrate through the nuts to the steel bolts) I carefully soldered the brass nuts where they were, on one of the operating arms where it pivots on the post and to the ends of the operating arms where the shutter tags fasten on. Gentle tightening of the bolts removed a lot of the looseness and the shutters then operated smoothly.

Phew! That's enough for now. Hope it's not too boring....
Next will be the link to the signal arm…

Edited June 2, 2015 by Jon Fitness

[Pugsley]

Phew! That's enough for now. Hope it's not too boring....

Definitely not boring, fascinating more like! Keep up the good work B)

[The Stationmaster]

Interesting this - I'm now waiting to see how the balance lever for the signal arm is arranged.

[Jon Fitness]

Interesting this - I'm now waiting to see how the balance lever for the signal arm is arranged.

Hmmm... this is where modelling accuracy, the design of the kit and the bits supplied and the practicalities of operation will all disagree...theres a spring involved .

More soon as I'm at work (nites) and can't upload pics from here...

JF

[Jon Fitness]

Here's a quick question!

What colour did BR(W) paint their signal posts? was it silver or silver-grey or battleship grey? I've tried several shades on past signals but they've never looked quite right to me and I've always had to weather them quite heavily before they looked ok.

I'd be looking for a suitable Halfords spray can for covenience!!

JF

[The Stationmaster]

Here's a quick question!

What colour did BR(W) paint their signal posts? was it silver or silver-grey or battleship grey? I've tried several shades on past signals but they've never looked quite right to me and I've always had to weather them quite heavily before they looked ok.

I'd be looking for a suitable Halfords spray can for covenience!!

JF

It was 'silver' John (in reality a shade of 'aluminium' I would presume but it gave a very silvery finish when new and weathered very well in most situations). Years ago I always took the view that Humbrol 'aluminium - I forget the number alas - was a pretty close match for it. It is avery different colour from that used by any other Region the closest probably being that used by the Eastern (not the North Eastern) in the 1970s although that always looked a shade or two duller than the Western colour. Alas I've not got any 'modern' Painting Instructions for WR S&T stuff but some properly coloured examples can still be found notwithstanding the incursion of all sorts of horrendous oddities due to boundary changes and the whim of local engineers from the 1980s onwards.

 

Although the example below is a colour light this shows what the colour is like after years of weathering (I can't remember when this signal was last painted but it has certainly not been touched in the last decade) - the pic was taken in more or less direct afternoon sunlight and I think is a pretty good rendering of the colour as weathered but the paint used to take some years to become this dull.

[Jon Fitness]

Mike,

Many thanks for that! I always thought "silver" just looked a bit too bright though. It seems to weather almost to grey but never seems to look tatty. Off to Halfords now...

JF

[Jon Fitness]

Right, now I have the shutters working, it’s time to get the arm linked up as well.

As the arm is worked from the shutters, there is no direct link from the operating mechanism to the signal arm. Each shutter will be worked by a separate servo and will push the arm to the off position as it does.

Here’s where the mechanics go a bit awry.

GW signals (along with other lower quadrants) are designed so that if any part of the linkage fails the arm will automatically return to danger. This works on the real thing because the spectacle plate is heavier than the blade and naturally lifts the arm back to horizontal. On the model version, the reverse happens as the spec plate is half etched thin brass!

To counteract this I started by considering a weight bar added to the mechanism (too complicated and not enough weight could be added and still look ok) or add a tubular weight to the down rod from the signal (again, too bulky)

Time to cheat then. Within the support bracket for the shutter casing (where I routed the down rod for the arm) I slotted in a small spring over the rod. A small peg was soldered to the wire beneath the spring so that when the wire was pushed up, the spring was compressed. This made sure the signal returned to danger. A small piece of wire was then soldered to the down rod across the top of the shutter actuating arms so that when an arm lifted, so did the down rod.

A bit of “adjustment” was required to get the stroke right to work both arm and shutter in harmony, and a small notch in each operating arm proved necessary to stop the wire slipping along the arm as it worked against the spring.

Another addition was a “sleeve” over one side of the cross wire on the down rod to equalise the lift on each shutter

Not quite prototypical but fairly effective.

Once I had the arm and shutters working together, final drive rods were fitted down through the base plate to meet up with the micro servos I’m using. I shortened the actuating arms as I thought the stroke required was a little excessive and the rods would stand too far from the post, possibly.

I like to fit the servos to the base of the signal rather than a separate under baseboard fitting; that way I can set everything up on the bench and just “plant and plug in” on the layout.

A length of scrap etch was used to fabricate a simple mounting for the servos on the base plate and the support at just one end of the servo seems sufficient for the small effort required to move a signal arm.

Once I knew where everything was going to fit (good old trial and error!) I could get on with finishing off the rest of the signal bits like ladders and staging. I also found a place to fit the 1k Ωresistor on a small piece of PCB tucked under the baseplate.

Time to strip it back down, clean up and paint it.

[The Stationmaster]

Nice John - I thought that would be your solution when the word 'spring' appeared. Of course the next bit will be fretting out the route names

[garethevans1986]

Looks good Jon, where is it going to live?

 

Gareth

[Rugd1022]

Now that is a thing of beauty, no question about it! Looking forward to seeing it painted and installed

[beast66606]

Very nice work - as usual - Jon.

[Jon Fitness]

Nice John - I thought that would be your solution when the word 'spring' appeared. Of course the next bit will be fretting out the route names

I think the word is "printing"...... .....

JF

[Jon Fitness]

Looks good Jon, where is it going to live?

 

Gareth

 

I think you've seen where it is (photos soon when I've corrected the schoolboy error on it )

Now that is a thing of beauty, no question about it! Looking forward to seeing it painted and installed

Cheers, See above!!!

Very nice work - as usual - Jon.

Ta. Praise indeed!

Just a little error to correct on it and I'll post a few pics of the finished article

JF

[Jon Fitness]

Stripped down and painted in primer (grey for the post structure and white for the arm).

The finished article will be painted in BR(WR) silver and black rather than white and black, reflecting the era depicted on the layout.

Before anyone says owt, yes I know the stencils should be black on white not white on black..serves me right for trusting “instructions” rather than checking a few pictures!!! (It’s been sorted now)

Component parts now in finished colours, the red and green spectacles were bashed from MSE coloured plastic lens material using appropriate sized hole punches and glued to the spec. plate with superglue gel.

Once that was done, the signal was re-assembled, the servos fastened up to the base and the drive rods positioned.

To check it all worked I built up another MERG driver board and made it ready to couple up to the servos.

 

Usual sequence for coupling the servos is

1. Remove servo horns from servos.
    
    
   
2. Couple up the servos to the driver board and they should automatically find the centre of their travel
    
    
   
3. Feed the drive rods through the hole in the horns and fit them to the servos so that each signal arm is in a mid position.
    
    
   
4. Couple up the tuning box to the servo driver board and go through the tuning sequence, checking that the signal will swing easily from On to Off.
   

 

 

The signal is now installed and working on the layout. One of the servos is a bit “buzzy” and I think it may be a quality issue!

Video of it working below

Cheers

Edited September 15, 2011 by Jon Fitness

[micknich2003]

John, a very nice piece of work Surely the spectacle glass should be Blue and not green, or is it a trick of the light? Nevertheless an excallent model. Mick.

[The Stationmaster]

I think the 'fiddle' with the spring has worked very well John and the colour is absolutely spot on (including the finial - something sometimes missed being the use of both black and silver) apart from the foot of the ladder which should be aluminium to the same height as the black on the signal post - or is it being hidden by a trick of the light?. The base of the post looks a little bare without any wire cranks butI can appreciate that they might foul the two down rods. Overall a smashing job which definitely captures the feel of the signal and 'cash register'.

[Jon Fitness]

John, a very nice piece of work Surely the spectacle glass should be Blue and not green, or is it a trick of the light? Nevertheless an excallent model. Mick.

Cheers Mick.

Spec colours, always a bit of discussion about that....I use warm white LEDs so I have to use green lenses. I've tried blue but it tends to stay blue! If the light source was yellow then yes.. I'd use blue but yellow LEDs turn the red orange!!

JF

[micknich2003]

Cheers Mick.

Spec colours, always a bit of discussion about that....I use warm white LEDs so I have to use green lenses. I've tried blue but it tends to stay blue! If the light source was yellow then yes.. I'd use blue but yellow LEDs turn the red orange!!

JF

John, thanks for your reply, a bit like the prototype, but in reverse. Best Wishes, Mick.

[Jon Fitness]

I think the 'fiddle' with the spring has worked very well John and the colour is absolutely spot on (including the finial - something sometimes missed being the use of both black and silver) apart from the foot of the ladder which should be aluminium to the same height as the black on the signal post - or is it being hidden by a trick of the light?. The base of the post looks a little bare without any wire cranks butI can appreciate that they might foul the two down rods. Overall a smashing job which definitely captures the feel of the signal and 'cash register'.

Thanks Mike.

Most of my signals seem to have black ladders to the floor.

I have checked many pics of Ex GW sigs and about 50% seem to have black ladders to the floor. Even more with the Ex LMS or BR upper quadrants.

Also as I am a bit of a lazy so and so, cranks and weight bars tend to be forgotten at the base of the post as the eye is drawn to to worky bits!

JF