LF's First 4mm Scale Semaphore Kit

Continuing on with the action, the spindle bearing which holds the arm spindle is 1/16" tube and is soldered in a cruciform arrangement exactly 4mm from the top of the post. I once again drilled a 1/16" hole into the timber to keep the bearing vertical.



You can see that at the 4mm mark I filed using a round needle file a groove into the post which resulted in a smoother joint between spindle bearing and post. This isn't in the instructions however, just something I thought would be good!

I found the pins to be more than adequate at holding the whole thing together enabling both hands free to solder. Applied some flux with the old paint bruch, tinned the iron and applied to the joint. Too easy and no clean up of the joint required.



Once soldered in I cut the bearing down to size, allowing about 1mm to protude on either side of the post. I used the Xuron cutters again and drilled out the inside of the bearing tube with an 0.8mm drill to take care of any distortion. Next came a dry fit of signal arm spindle and spindle bearing which was quite exciting I must say! The holes in the block of wood prooved most useful.



Next came the soldering of the butt to the post whish was pretty straight forward with the post simply forming an interference fit inside the top of the butt and a little solder applied. This was then filed down to a bit of a bevel and smoothed all over with some emery which has come up well.

I don't have areal good close up of the butt to post connection but will get one later.

I then added the butt to base plate and soldered it up. I differed from instructions by drilling out a 2.5mm hole in the base plate and inserting the butt into this hole, applying solder and then filing flat. This gave access right through the tubes if I wanted to insert the LED wire up it as per another thread on here.



Lots of blobby solder here but I used a solder wick, reheated it and sucked most of it up. The hard part was keeping the signal perpendicular to the base plate in all planes however this was achieved by sight fairly easily.

I then clamped the base plate to my timber block to provide a firm platform for the attchment of the balance arm bracket that was easily folded up from the half etched fret item and then soldered to the butt. Sorry for the slightly blurred image here.



You can see the red pen marking in the middle of the bracket. This was to mark the centre line of the balnce weight pivot from the baseboard and the block of wood once agin prooved a useful assembly jig. Finally I assembled the balnce weight by pretinning the two arms on the fret and sweating them together as per the signal arm. I then tinned two separate balance weights and applied them in the same manner building up a complete balance weight assembly. Once complete I drilled out the axle hole and the operating crank holes with the appropriate micro drill bits in the pin vice. No power tools needed here!



Thats all I have photos of at the moment but I have connected the balance weight arm and axle assemble, installed a lower ground grank and installed the working LED as a signal lamp. I will add these photos too if there is some interest.

Thanks all, hardly qualified after first attempt to take commissions!! Have a go your self first and see how easy it is. This is my first ever soldered anything!

Carrying on, here is a photo of the installed balance lever and non working crank. No real point of trying to make the crank work unless operating it from parallel to the baseboard (ie above board).



Here is a similar view of the detail. To ensure the balance lever didn't get soldered up when securing the axle in place I "painted" the balance lever bearing with a permanent marker pen that apparently the solder doesn't stick to. The instructions call up oiling the bearing but I didn't have any oil nor did it elaborate on what type to use. I assume some form of sewing machine type oil would have sufficed however the lever works fine using the marker pen method.



By the way I am going with a larger size of photo to hopefully make up for my lack of macro lens capability in my Nikon!

This is the front view of the signal showing the modified LED complete with the casting top from an MSE Adlake lamp casting, simply cut off with my sprue cutters and filed smooth, CA glued in place on top of the filed LED. Note that the lamp bracket is slightly askew. This is because the triangular bracket on the fret went into orbit somewhere in my loft when releasing it from the fret. That meant that I decided to fashion the diagonal from the leg of the LED instead to provide a robust electrical connection. Twisting the LED leg through several turns to get it to end up in what you see is a miracle in itself and frankly is barely noticable after the signal arm is in position and obscuring it.



The reverse view of the lamp hopefully giving a slight indication of what I did. The legs of the LED (anode and cathode) are vertically orientated ie one on top of the other. This had some advantages and disadvantages in assembly. The main advantage was using the lower leg as a part of the bracket mentioned above while the disadvantage was that the upper leg need a wire soldered to it. Once it is painted black however and the wire secured I am positive no-one will pick it out on the layout!



A slightly closer view of the rear of the lamp showing the wire soldered to the LED. Note that the rest of the signal is live and is the positive feed and then only one wire is required as the negative to make the LED work, saves a wire.

I then secured the signal to my block and prepared it for installation of the track sensor plate which is the lozenge shaped sign that tells the driver that detection is in place and he doesn't need to contact the signal box in any way (that's my take on it - if I'm wrong someone here will sort it out )



Once agin the item was burnished on the fret and lightly tinned to the reverse. The obverse carrys 4 indentations representing securings to the post, vertical pair and horizontal pair. I chose horizontal and filled the two vertical ones with a touch of solder, filed nice and smooth after installation. I applied a little flux to a clean part of the post at the height suggested in the instructions and after getting a firm hold with my tweezers I sweated the sign in place.



Prior to installing the sign I had leapt ahead with allder installation. Rather than create a 5mm slot with a Dremel like device that I don't posess I sized a drill bit that looked like it would create a hole large enough to receive the ladder stiles if inserted in it. This prooved to be about a 1mm hole and I drilled two holes into pre punched marks using my new scriber courtesy of Richard! Now it would have been better and easier to have done this marking out with the benefit of the scribed longitudional line previously marked onto the base plate however I soldered the post in the wrong way resulting in said scribe marking appearing now on the under side of the base plate - most helpful!



While having drill in hand I drilled a further 1mm hole right at the base of the post at the rear to take the wre for the LED to be threaded through later. I used this hole to secure the signal base plate to the timber block while playing with the ladder as can be seen in the following photo. Here I have fully tinned the ladder while on the etch by lightly burninshing with the fibreglass pen, more gently now to alleviate the shards of fibreglass that end up in my hands. Once burnished I apllied a light application of flux using my paint brush and then the tiniest of touches of solder to the clean tip and then run along each stile and rung resulting a perfectly tinned ladder etch on both sides. All very easy yet probably one of the activities that scared me the most initially. The ladder has its upper most rung removed with the fret cutters and then filed with the emery board to remove any traces of the rung. I then folded it as per instructions. I roughly sighted the bottom end of the ladder and cut of ecess rungs leaving a couple of stiles that could be poked through those previously drilled holes. By the way the distance of the ladder bottom from the post is given in the instructions for various ladders and that is all I used for this one.



Once cut roughly to size and secured in the lower holes I kept a close eye on the top before making the bottom secure in the two holes as per the photo. Once secured a touch of the iron secured the ladder to the mounting block installed simply from the part supplied on the etch; cut, filed, and slid over the pole. I decided to make mine a little more realistic by spiltting it at the front. This also eased installation too.

Once I was happy with the ladder at the top and the bottom I then burnished and tinned the stays as supplied on the fret. Two pairs are provided however given that this is one of the shorter signals at 16' I decided to use one pair centrally mounted. Whether this is prototypical who knows however it appears from signals that you build it and you will find te prototype somewhere!

The stiles were secured by tinning the pole with flux and a hot tinned iron at the point I wanted them to join however they are not meant to fall at the same point as a rung on the ladder so I offset mine slightly. Now I didn't want the heat of this application to melt my track detection sign either so I made them alittle lower but they look fine to me.



Next came the safety hoop which was formed from th fret, burnished and tinned (seeing a pattern developing yet?) It was wrapped around the shank of a 7mm diameter drill bit as suggested in the instructions and when let go it springs out to an 8mm size which apparently is correct.



I then faffed around trying to secure it 4mm below the centreline of the signal arm bearing (near enough and don't play too much with it after!)



There was probably some jig I could have built to accelerate this proces but that will develop as the next 50 or so signals do.

A nice closeup showing the bearing, lamp, ladder, hoop etc all in place.



A broader view showing the entire signal with all construction soldering now completed except for thback blinder which will happen after painting (tomorrow!)

Carrying on with the signal construction here are a couple more shots showing the painted and weathered signal in need of its operating linkages.



I then made up a tiny circuit to run the LED with a 1k Ohm resistor in series with a 10k trimpot that allows me to adjust the voltage applied to the LED and ths the brightness. This cost cents to make and minutes to put together and will be usful for adjusting the brightness of the LEDs across the layout depending on where they are sighted and where operators of the layout are situated, that way I can customise the lighting brightness for each signal. I would need terminals anyway for the connection of the wires so this is not really a big deal extra. I could measure the resistance across the trimpot if happy with the brightness and install a fixed value resistor if I wanted to aswell.



I have also started experimenting with control devices to drive these signals. As I need around 40 or so of them I was keen to come up with a low cost, realistic movement, repeatable installation method and am experimenting with a number of solutions. The first is memory wire shown in the following photo with the fine wire contracting when current applied and the spring returning the crank back to original position. You get about 3mm of movement per 100mm length of memory wire making this almost right for the movement required to activate a 4mm scale signal.



I have built a Mark II version too which is much better and will take a pictuyre of it over the weekend. It is off to see Richard Johnson today!

I attended the Perth (WA) model railway show last weekend and picked up this neat little gearbox kit which I thought may offer an alternate solution for signal control.

Here is the pack on the right along with some other goodies I picked up too!



The parts are laid out here.



I then assembled the frames of the gearbox and inserted the motor.



One additional point to make is that I pre-tinned and soldered the motor drive wiring before assembly to avaoid theneed for having a hot soldering iron near the plastic framework.



The rods slide in and then you pick as many of the gears as you want to add depending on the reduction ratio your require. Each gear to pinion is a 4:1 ratio so two gears gives 16:1 and so on. Using all the gears as I have here has brought the final gear speed down to 2-3 RPM which is very slow and may well be close to the speed I need to drive signals. The company also offers a rack and pinion accessory that may well be ideal for converting the circular gear movement to linear drive.

The whole kit cost me a tenner (5GBP) which is great value however I feel that they may be a little noisy even when running of 1.5Volts as I did for this experiment (I used a AA battery). I will perservere with it though if for no other reason than to rule it out as being too noisy - the only issue I see as it is cheap and repeatable in it construction.

The company is based in the UK and is called MFA / Como Drills. I would be pleased to hear from anyone who has used there rack and pinion set with a gear box or has another solution that may work. I am thinking about chopping some of the excess length of the main shaft and inserting it in one of the 4 aux holes shown in the gears as this would provide the linear movement possibly.