Midland Bracket Signal
Posted: Mon Jul 21, 2008 8:05 pm
I thought some might be interested in the construction of Brinkley's Down Home bracket.
The posts are made from real timber. The wood used was purchased from an aero modelling shop. I believe it is lime. It was perfect for the job as it is, strong, light in colour and has a nice fine grain. It also came in quite useful sizes for 4mm scale signal modelling. Having said that there are unevitably some sizes that aren't avaiable but I also purchased a miniature plane for shaping rectangular sections. It is nice to work with and doesn't splinter or split when cutting or filing it. The cross braced double post base is made from two lengths of 4mm square for the verticals. Horizontal and diagonals were made from 3mm x 2mm and 2mm square respectively. All the parts were glued together with PVA and where necessary, for comestic effect, dowelled with bits of brass rod. The tops of the verticals were rebated where the long bracket trimmers attach so that they had the correct spacing for the dolls at the other end. The dolls themselves were slightly tapered with the plane before gluing on a whitemetal finial from Model Signal Engineering (MSE). The finial sides were filed to match the post dimensions and the dolls where then glued/pinned between the trimmers.
All of the mechanical parts and ironwork are from MSE except for the balance weights and push rod cranks. The balance weights are Alan Gibson parts and the cranks were made from scratch. These were probably the most difficult job of the whole signal. I was not happy to use overscale etched parts but I must have made twice the number of cranks to get the four you can see in the picture. The push rods and gantry railings were made from 0.3mm nickel silver wire. The ladder was also from Alan Gibson and is one of these fold up jobs with wire rungs. When I first made one of these it ended up rather mishapen due to distortion from trying to solder it up with a soldering iron. After a bit of lateral thinking I came up with a little trick to getting these perfectly straight. I fold it up and insert cut lengths of wire through all the holes. Then put a dab of solder cream at the joint between the rung and each stile. It takes a while but the preparation pays off in the next step. I put the assembly on an old baking tray and stick it in a preheated oven on full power (mine does up to 240 degree celsius) for 10 mins or thereabouts. Everything heats up evenly so does not get distorted. Turn the oven off after you see the solder has melted and let it cool down naturally. A perfectly straight ladder is the result. There is a lot of cleaning up afterwards but there always is with this type of ladder construction.
The painting was done with a spray can of matt white Halfords primer. Very light coats from almost every conceivable angle followed by close inspection for any bits that were missed. I don't bother to try and mask the moving joints I just make sure I move them as the paint drys and nothing has gummed up yet. In fact things only tend to get sticky with the brush painting of the black bits (I use Railmatch weathered black). A bit of movement and light clock oil usually frees things up. The arms are painted last. The spectacle glass is done by putting a piece of low tack masking tape on the front face and then drip a bit of PVA glue into the ring. Leave overnight to go off then the colouring was done with some blue and red glass paint on both sides. One final thing to note on this is to leave the lamp off until now as it makes doing the spectacle glass easier. Last job was a bit of light weathering.
Cheers.......Morgan
The posts are made from real timber. The wood used was purchased from an aero modelling shop. I believe it is lime. It was perfect for the job as it is, strong, light in colour and has a nice fine grain. It also came in quite useful sizes for 4mm scale signal modelling. Having said that there are unevitably some sizes that aren't avaiable but I also purchased a miniature plane for shaping rectangular sections. It is nice to work with and doesn't splinter or split when cutting or filing it. The cross braced double post base is made from two lengths of 4mm square for the verticals. Horizontal and diagonals were made from 3mm x 2mm and 2mm square respectively. All the parts were glued together with PVA and where necessary, for comestic effect, dowelled with bits of brass rod. The tops of the verticals were rebated where the long bracket trimmers attach so that they had the correct spacing for the dolls at the other end. The dolls themselves were slightly tapered with the plane before gluing on a whitemetal finial from Model Signal Engineering (MSE). The finial sides were filed to match the post dimensions and the dolls where then glued/pinned between the trimmers.
All of the mechanical parts and ironwork are from MSE except for the balance weights and push rod cranks. The balance weights are Alan Gibson parts and the cranks were made from scratch. These were probably the most difficult job of the whole signal. I was not happy to use overscale etched parts but I must have made twice the number of cranks to get the four you can see in the picture. The push rods and gantry railings were made from 0.3mm nickel silver wire. The ladder was also from Alan Gibson and is one of these fold up jobs with wire rungs. When I first made one of these it ended up rather mishapen due to distortion from trying to solder it up with a soldering iron. After a bit of lateral thinking I came up with a little trick to getting these perfectly straight. I fold it up and insert cut lengths of wire through all the holes. Then put a dab of solder cream at the joint between the rung and each stile. It takes a while but the preparation pays off in the next step. I put the assembly on an old baking tray and stick it in a preheated oven on full power (mine does up to 240 degree celsius) for 10 mins or thereabouts. Everything heats up evenly so does not get distorted. Turn the oven off after you see the solder has melted and let it cool down naturally. A perfectly straight ladder is the result. There is a lot of cleaning up afterwards but there always is with this type of ladder construction.
The painting was done with a spray can of matt white Halfords primer. Very light coats from almost every conceivable angle followed by close inspection for any bits that were missed. I don't bother to try and mask the moving joints I just make sure I move them as the paint drys and nothing has gummed up yet. In fact things only tend to get sticky with the brush painting of the black bits (I use Railmatch weathered black). A bit of movement and light clock oil usually frees things up. The arms are painted last. The spectacle glass is done by putting a piece of low tack masking tape on the front face and then drip a bit of PVA glue into the ring. Leave overnight to go off then the colouring was done with some blue and red glass paint on both sides. One final thing to note on this is to leave the lamp off until now as it makes doing the spectacle glass easier. Last job was a bit of light weathering.
Cheers.......Morgan