Dave Holt
Western Thunderer
Seeing as progress with my Ivatt 2 tank is so glacially slow that there is no visible (or even invisible) progress to report, I thought I might post something about one or two of my other loco projects which are now complete.
I'll start with the BR Standard version of the Class 2 tank which, like its full sized equivalent, shares a lot in common with the Ivatt predecessor.
In this case, the model is based on a DJH kit rather than the Bachmann RTR body. As is typical of DJH, the kit is a mix of etched sheet and white metal castings, the quality of which is generally good. However, there are exceptions as I discovered after assembling the basic tank/cab/footplate assembly. The original intention was to make a new chassis using hand cut frames. The valve gear presented a problem because the DJH parts were already part assembled and didn't really meet my aspirations. Whilst I pondered the issue, Comet produced their chassis kit for the Bachmann Ivatt, so the solution was at hand. Comparison of the Comet frames and part assembled body caused some consternation when the frames were found to be 2 mm longer than the body. A dimensional check of the scale drawings showed that the body was short and, in effect, the whole error was in the length of the cab. Sods law, the error was spread over several parts of the cab, so the only viable option appeared to be to widen the cab opening and live with the resulting inaccuracies.
Modification of the part built body didn't really seem practical, so a second kit was purchased so the tank/cab/bunker etching could be modified in the flat, before folding the sides up. A suitable width fillet strip was inserted after cutting right across the etch, in the cab opening. Great care, and use of straight edges, helped ensure proper alignment during soldering in of the fillet. Of course, this modification would mean the cab doors and roof would no longer fit, but that could be sorted later.
A difference between the Bachmann and DJH bodies was that the former uses a full length chassis, whereas the latter is designed to have short frames from the front of the cylinders to just behind the rear coupled wheels, with the parts of the chassis over the pony trucks being part of the body. I decided to stick with this arrangement as it works just as well but results in the bearing pintles for the trucks being attached to the body rather than the chassis.
Otherwise, the two models are very similar in construction, with detailed differences to reflect the use of BR standard components in some areas.
Here is the basic tanks/cab/bunker/footplate unit, without the boiler. This is as far as the first attempt got, although that earlier version didn't have any of the pipework, steps, buffers, etc., seen here.
As with the Ivatt, the cylinders and valve gear are a separate assembly. The two different types of truck are also shown. In this case, they are based on the Brassmasters iten with one modified to represent the swing link type.
As mentioned, the frames are short, just making an 0-6-0! The keeper and brake rigging are similar to the Ivatt.
My original idea to lengthen the cab roof was to use the two cast white metal items I had (from the two kits). I pondered for some time how to be able to cut and shut the two castings to result in a neat, square job. In the end, I decided to get an etched brass roof made as part of a series of bespoke etchings I commissioned from Rumney Models (other parts included balance weights, push-pull vacuum diaphragm support brackets, tank retaining straps, lamp irons, shed/SC plate mounting and maybe others I can't remember just now!).
Here's the body with roof on and most of the other details added. I'm rather pleased with the push-pull gear and associated piping. The only parts of the original DJH kit are the vertical steam pipe covers, and even they had to be lengthened with some plastic card packers. Most of the brass boiler fittings are Alan Gibson castings but the brake ejector is scratch built from umpteen parts.
Finally, some shots of the finished loco, painted, lined and weathered by David Clarke. Crew are from the rather nice Modelu range.
Dave.
I'll start with the BR Standard version of the Class 2 tank which, like its full sized equivalent, shares a lot in common with the Ivatt predecessor.
In this case, the model is based on a DJH kit rather than the Bachmann RTR body. As is typical of DJH, the kit is a mix of etched sheet and white metal castings, the quality of which is generally good. However, there are exceptions as I discovered after assembling the basic tank/cab/footplate assembly. The original intention was to make a new chassis using hand cut frames. The valve gear presented a problem because the DJH parts were already part assembled and didn't really meet my aspirations. Whilst I pondered the issue, Comet produced their chassis kit for the Bachmann Ivatt, so the solution was at hand. Comparison of the Comet frames and part assembled body caused some consternation when the frames were found to be 2 mm longer than the body. A dimensional check of the scale drawings showed that the body was short and, in effect, the whole error was in the length of the cab. Sods law, the error was spread over several parts of the cab, so the only viable option appeared to be to widen the cab opening and live with the resulting inaccuracies.
Modification of the part built body didn't really seem practical, so a second kit was purchased so the tank/cab/bunker etching could be modified in the flat, before folding the sides up. A suitable width fillet strip was inserted after cutting right across the etch, in the cab opening. Great care, and use of straight edges, helped ensure proper alignment during soldering in of the fillet. Of course, this modification would mean the cab doors and roof would no longer fit, but that could be sorted later.
A difference between the Bachmann and DJH bodies was that the former uses a full length chassis, whereas the latter is designed to have short frames from the front of the cylinders to just behind the rear coupled wheels, with the parts of the chassis over the pony trucks being part of the body. I decided to stick with this arrangement as it works just as well but results in the bearing pintles for the trucks being attached to the body rather than the chassis.
Otherwise, the two models are very similar in construction, with detailed differences to reflect the use of BR standard components in some areas.
Here is the basic tanks/cab/bunker/footplate unit, without the boiler. This is as far as the first attempt got, although that earlier version didn't have any of the pipework, steps, buffers, etc., seen here.
As with the Ivatt, the cylinders and valve gear are a separate assembly. The two different types of truck are also shown. In this case, they are based on the Brassmasters iten with one modified to represent the swing link type.
As mentioned, the frames are short, just making an 0-6-0! The keeper and brake rigging are similar to the Ivatt.
My original idea to lengthen the cab roof was to use the two cast white metal items I had (from the two kits). I pondered for some time how to be able to cut and shut the two castings to result in a neat, square job. In the end, I decided to get an etched brass roof made as part of a series of bespoke etchings I commissioned from Rumney Models (other parts included balance weights, push-pull vacuum diaphragm support brackets, tank retaining straps, lamp irons, shed/SC plate mounting and maybe others I can't remember just now!).
Here's the body with roof on and most of the other details added. I'm rather pleased with the push-pull gear and associated piping. The only parts of the original DJH kit are the vertical steam pipe covers, and even they had to be lengthened with some plastic card packers. Most of the brass boiler fittings are Alan Gibson castings but the brake ejector is scratch built from umpteen parts.
Finally, some shots of the finished loco, painted, lined and weathered by David Clarke. Crew are from the rather nice Modelu range.
Dave.
