I have just started on the construction of a rather unusual model.  A GWR Broad Gauge locomotive of the Waverley or Abbot class. I am hoping ( fingers crossed ) this will turn out alright and I can put details of the construction process on the website.

The above picture shows the wheels for the locomotive which I have turned up from castings. Most models of the broad gauge today are built to S7 standards but this one is built to ordinary fine scale using a track gauge of 49mm. After turning up the wheels the next job was make the axles which are 47mm in length. The smaller wheels are tapped 4BA and screw on the axles.Insulation being by means of a plastic bush. The driving wheels are insulated at the tread.I cut a groove in the castings which I filled with Araldite which I then allowed to cure for a couple of days. When it was firmly set, I turned the wheel round and cut another groove till I could see the adhesive. Then I filled that up with Araldite and left it to dry. One pair of wheels are flanged and the other pair is flangeless. This is as per the prototype which although it looks like a 4-4-0 engine is in fact 2-2-4-0.

 

 

Apologies as the above picture is not terribly clear. I will try and take another one later.It shows the basic main frames of the engine which are made from 1/16 thick mild steel. A lot of modellers today use thinner materials but I prefer something heavier. Using this sort of material I know that once its been drilled in my pillar drill it can be screwed together, be square and provided the wheels are correct I will have not any problems with quartering and getting the chassis to move smoothly. I also wanted some substantial frames because the home turned driving wheels are a force fit on their 3/16 axles and should I need to remove them will require a fairly hefty tap with a hammer. Thinner frames would not stand this. These are only the basic frames. They will be covered in an overlay which I will come to later.

 

 

The above picture may not look very interesting but it does show some of the more vital parts of the chassis. Top left are two brass frame spacers fitted with 6BA screws. These have been machined to exactly the right length (40mm) and hold the steel sub frames apart . Next to them are the main axle bearings made from 5.5mm O.D. diameter brass tube. This has a bore of 3/16 and I use this a lot as a bearing. A small hole will be drilled in the tube so that I can  add oil from time to time. The axle thus running in a little oil bath. The two bearings on the right have been made from 5.5 mm tube with an added sleeve. These two tubes will be soldered together so I can have a bearing that will be able to go up and down but not from side to side. These are for the smaller leading wheels on the loco. The two other parts are the coupling rods milled and filed up from 1/16 mild steel and drilled to take the 8BA crankpins. During a trial assembly I put the all the parts so far made together and had a smooth rolling chassis in a few minutes.

 

The above picture shows all the parts made so far with the addition of the cosmetic sideframes. I glued a photocopy of the drawing I'm working from onto two pieces of 15 thou nickel silver which I then cut out with a piercing saw. I then added the rivet detail etc.  The cosmetic frames will be added to the main frames using solder or adhesive. I might assemble the whole frames next or possible revert to the tender and get the wheels and chassis prepared for that. Either way thats about it for now. I'll add more as I get to it. 

  

Friday 5th Feb 2010.

The above picture shows a trial assembly of the sub chassis. It is resting on the ground surface table of my vertical drilling machine. You will notice the gap at the left hand side which shows its not sitting level. This is a recipe for disaster . All chassis must be checked against a flat surface i.e piece of plate glass or mirror if you have not got a surface table. Any trace of rock must be removed before going any further.

I checked on the tightness of the screws and here is chassis now resting truly on the surface table.

Here are all the components put together. The next job is to solder in the brass tubes for the driving wheels and I also want to add a plate over the leading wheel which will be used to hold the body on and also have the fixing screws for the smokebox. After I have done that I can solder on the cosmetic frames which will of course cover up the frame spacer screws so I must make sure that they are tight and chassis is square and true. i.e. no rock!.

 10th Feb

Spent some of yesterday in my ice box of a workshop. The picture below shows some of the bits and pieces I made. The two parts on the left were cut from 1/16 brass sheet and form the back and front of the firebox. The two discs were cut on the lathe and will be used to form the boiler. The pieces on the right will be forming the smokebox. The tube will be the boiler and was rolled up from 10 thou nickel silver. The reason for using thick brass for the firebox is that on the real locomotive, the front and rear were highly polished brass. I will be fixing on two further cut outs which will be very slightly smaller. These will then form a rebate to which the wrapper itself can be added. I have also cut out the footplate. In common with a lot of these early engines there is a gap behind the buffer beam at the front presumably to give access to the cylinder end covers.

 

 

 I have now temporarily bolted the discs to the front of the firebox and the rear of the smokebox.

 

 

When building a model I very frequently do trial assemblies to make sure that things are going to fit and are square. I have used some long 6BA bolts to bolt the firebox and smokebox together and also added the boiler. This engine must have been quite a large one for 1855. On the drawing it is very difficult to work out the exact diameter of the boiler but I estimate it to be 34mm. The smokebox is approximately 6 foot high. This engine has enormous cut away splashers which should improve the appearance somewhat. I will need to cut away some of the boiler and the front of the firebox to accommodate the motor.  Still a lot to do but I was pleased to see that the underneath of the boiler is parallel to the footplate.

14th February 2010.

Further progress. The firebox and smokebox have now been assembled. I cut two further pieces for the firebox slightly smaller than the originals seen in the other pictures.Then the two parts were sweated together forming a rebate into which I soldered the outer wrapper which is made from 15 thou nickel silver. The brass disc has been bolted on at the same time.

The smokebox has had the rivets added and the out wrapper from 10 thou nickel silver. Again the brass disc has been sweated on but you cannot see it in the picture

 

This picture shows the underneath of the fire box and smokebox. You will notice two brass strips which have been soldered in on the firebox and another piece onto the smokebox. I then temporarily soldered the smokebox onto the footplate and drilled through both with a 1.4mm drill. This is tapping size for 10 BA. I tapped the holes and then drill through the footplate with a clearance drill of 1.8mm.

Once the firebox could be screwed into place I added the boiler which fits nicely onto the two discs and the firebox which I also temporarily soldered into place. Drilling and tapping it as per the smokebox.

 

The smokebox, boiler, firebox have now been screwed to the footplate with 10BA screws. Here is a picture of the assembly so far. Thanks to the generosity of my good friend and ace locomotive builder Fred Lewis, I now have a large supply of brass so my next step will be to make the large splashers which will requires some careful cutting out with the piercing saw.

 

 

15/2/2010

Using some 10thou brass from my friend Fred I was able to make the large splashers. I used a photocopy again  as a pattern and cut the sides out as a pair using a piercing saw. A strip of brass 6.5 wide was cut in the guillotine. I put the sharp bend between the driving wheels in first and gently bent the material round tack soldering as I went. Once it was all in place I soldered a nice even seam on the inside .Two large semicircular pieces were then marked out on a further sheet, cut out and soldered in place to the rear of the splasher.  All the splashers , footplate and boiler can now come off the frames and the boiler is detachable from the footplate. This will make detailing and painting easier. The basic locomotive is now done and I can start  the detailing. Actually that isn't quite true as probably the next job is to fit in the motor otherwise it won't be going anywhere!

 

 

22nd Feb. 2010.

Well as you can see I managed to shoehorn the motor in. Its a Mashima 1833 with 40;1 gears. The driven axle you may remember was in a tube well I simply cut a section of tube away to fit in the motor. The stub ends of tubes left in the frames will act as bearings.  I had to cut away a small section of the boiler and some of the front of the firebox  but on the whole it fits in quite well. I 've done a quick test by putting on the side rods and clipping on some power and she runs very nicely. I'm not surprised really as it was very free running with just the side rods.

 

 

 Not a terribly interesting shot . One or two points of interest. You will notice the hole in the leading tubes. They are  where I can put a drop of oil onto the leading axles. The little metal strip which is joining them is an anti rotation device to stop the tubes going round on the axles. The piece of angle is holding the motor in place. I drilled another small hole in rear axle tube and hole in the back spacer for an 8BA screw which will be holding the body and coupling to the tender on.

 

 

Back on the body again. You may notice that we now have a buffer beam. This has been made sandwich fashion with two strips of n/silver and a filling of a piece of 1/8th plywood. The original plan was to use a piece of paxolin but it proved to be a bit too thick. There is also beam now fixed at the back as well.

Now I have the basic locomotive done and the chassis parts all ready for painting and final assembly I thought I would move on to the tender. Rummaging round in my boxes of wheels I came across a set of six cast iron wheels. I started to make new axles but ran into a snag when the I found that the insulated bushes were too worn and would have to be replaced . So at the moment new bushes have been made, force fitted into wheels with the addition of a dollop of Araldite and they are drying on nice hot radiator at the moment. Back on the axles maybe tomorrow!.

 

 

Here is all the work completed so far. The engine is all screwed together and now has the motor fitted etc. Yesterday I managed to drill and tap three of the tender wheels and turned up new axles. The tender is a bit of a problem as I have no drawing for the particular one I want which has outside frames and springs above the frames alongside the tank. First job will be to make the chassis and ensure that both engine and tender are at the same level.More as I get to it.

 

 

 This rather uninteresting chunk of metal is the chassis for the tender. It is quite simply made out of 18 thou tinplate.Normally with thin materials for frames they waggle about all over the place but I wondered what would happen if I put a fold in . I marked out the frames on two pieces soldered together with an allowance for the folded portion. Drilled the holes for the brass tube bearings and then cut the frames to shape. Put the fold in using my metal bender and the result is immensely strong and quite light. Brass tubes were soldered in for the axles. you may notice the small oil holes. The middle axle has been given a bit of up/down movement and is prevented from moving from side to side but the little collar pieces soldered on. You can see them in the photo. A spacing piece was cut from another piece of tinplate and the thing soldered together. Actually I did make a slight mistake with measurements by not allowing enough for the wheel flanges. Measure twice , cut once is the motto though I never manage to follow it.

Here we are again with all the bits made so far. Its starting to look like a locomotive though there is a fair way still to go. I did manage to find a drawing of the tender which will help but there are lot of springs and things to make which will be fiddly and take some time. Will update the site as the model progresses.

 

Here are the results of a few more hours work. The 12 small parts are the dummy springs to go on the tender. They were made by soldering 5 pieces of nickel silver sheet together each piece being a slightly different width. They were then sliced up with the piercing saw rather like cutting a loaf of bread into slices.

The two long pieces are for the tender sides. Also the side frames have been cut out and the footplate with a beam added.

 

 

This shows the underneath of the tender body. You can just see two strips soldered to each side. These were folded up out of scrap bits of nickel silver. Two pieces of thickish brass are soldered to these. The chassis, footplate and body is then all temporarily fixed together and holes drilled which are then tapped enabling the whole thing to be screwed together.  The corners of the tender were made by making 5 small cuts in the flare and bending the sides  round a piece of 3/16 rod. The corners were then filled with solder and cleaned off.

The tender has now been virtually completed. I have added tool boxes and a box at the rear. The axleboxes were made out of brass channel with a top piece of thin brass. The rods going up to the springs are just a piece of brass wire soldered to the side frame. The turnings in the foreground are the three parts of the chimney. On the left is the cap, then the barrel which is a piece of tube and finally the seat which is a turned brass ring. The other little turnings are the buffers to which small pieces of brass tube have been soldered to take the buffer heads.

 

The buffer heads have been fixed on temporarily. The chimney was assembled from the three parts soldered together and fixed onto the smokebox. The  tender is virtually complete with steps, hand brake handle , tool boxes, springs , axleboxes etc and it all screws together to make the painting easier.  The next stage is to start detailing the locomotive but before I do that I must make sure it will pick up off the track and run okay.

 

 

Apologies for the very poor photograph. These two parts are for the smoke box door. I first soldered to pieces of nickel silver together , scribed out a circle which I then cut out. A chunk was cut off to give me the odd shape. Then the two pieces were separated and I cut the right hand one out with my piercing saw. I then soldered the two together to form the door.

Here is the finished smokebox door now fitted onto the smokebox. The bottom bits represent the hinges and the shorter little bits which are made of wire represent the clamps. Apologies for the poor quality photograph but it should give you some idea of what it looks like