The traditional wagon tarpaulin is one of those irritations of the modeller's life, but there are some good techniques that can reproduce these and the real thing is, after all, simply a large piece of rectangular treated canvas. Rather more complicated - and very common on wagons built or converted for the carriage of steel coil from the mid-'60s onwards - are the tailored sheets, not to be removed from the wagon and effectively considered part of the vehicle, which hug the shape of the three sheet rails. These have visible seams on the ends which show clearly in pictures and are really very difficult, in 4mm scale at least, to execute using the 'usual' techniques. I tried several some time ago when building my Shochood and hit upon something which seems to work. Perhaps someone else out there might be interested hence these 'in progress' shots. I make no claims to originality by the way, this is simply a variant on things military modellers have been doing for years!

The prototype, incidentally, is a 1964 conversion of a BR-built Pig Iron wagon, the Coil H. This was a very comprehensive rebuild which owed only a very little - mostly the floor - to the original design. There were only ten of them and I'm only aware of two published pictures and a weight diagram. The basic technique though should be more widely applicable even if it is a hassle.

The reason that I built the basic shell of the wagon with a peaked roof should be obvious - it acts as a former for the sheet to make the complete wagon durable and saves having to make the sheet rails fully detailed or properly functional - the wagon should never have moved without the sheet on so this detail is always hidden. Since I only have two pictures of Coil H, neither of which clearly show the ends (the sheets are in the way), I have little idea what these bits looked like anyway. My guess is probably something like this on the end of a Coil E (note that this wagon has lost its sheet rails):

http://paulbartlett....d78fd#h2f1b8757

So after the sheet rails themselves went on, formers from tinned copper wire were added over the top. the semicircular ones represent the seam on the sheet - shown here on a Coil A:

http://paulbartlett....aacce#h106159cf

The 'wiggly' bits of tinned wire represent the bottom of the sheet itself as a guide for what follows, a hint of which can be seen in the first picture.

The 'sheet' itself is added from Miliput (yes, this does look rough, but I just wanted the general outline at this stage, the second pass will smooth everything out and add more detail). The central section will be added using tissue in the familiar way.

Adam

Source: Adam's Workbench: a mid-'60s conversion - the Coil H