What is your problem with the drawings held at the NRM? Make a personal visit, ask to see the original drawings and fire away with your Digi camera, you can take as many pictures you wish, and all for free.
I don't have a problem with the drawings held at NRM, except the cost
. Sadly a digi camera wont work, it is not accurate enough, to get enough of the drawing in, other than standing on foot steps about 10 feet high, you need quite a wide lens, 24mm or so, that will produce parallax errors from anything outside of about 40% of the centre of the drawing. You also need to be at 90° to the drawing to get anything like near to scale across the image....negating the 24mm parallax errors already in process.
Even if successful you then need to stitch them all together and then print off or use as a base layer to draw over the top to get accurate scale drawings. At some point in the process you need to print off a set of drawings to make the parts from, unless you draw direct onto the material from the photos. I'm doing something similar with my SAR 18E,
in this case I've only got a GA to work from, but it gives the essential dimensions and by choosing photos carefully and minimising the parallax errors you can scale off them reasonably well, I say reasonably well, there are always errors but you have to decide if they are acceptable or not, in the case of a 1:32 A3 or A4 then 1-2mm error is not acceptable, for a SAR 18E where there is virtually no publicised data at all then 3-4mm error would be acceptable. That one photo of the 18E comes from a collection of over 700, I'd say 1-2% from that lot are usable for drawing aids, try and find 700 decent digital images of any UK steam engine on the internet, as a nation we just do not post good detail images on the net as much as other nations I'm afraid, but, it is a darn sight easy top pop down to your local preservation society and bag a hand full of detail shots, the same cannot be said for South Africa LOL.
If drawings are available then they should be used to get the best you can, and accepting the potential cost, if not then you have to resort to making your own as best you can. One other factor, making a personal visit, its over a 400 mile round trip for me and that's £70 worth of petrol, for that I can get nearly 4 lots of factory drawings of SAR steam locos.
I've also added a sample from the SAR steam site....a free sample anyone can download, just saving y'all the time to do it..... of one of their drawings for the GEA, the digital drawings I got from NRM for my WC/ BoB project for a very high price were no where near as good a quality as this.
Hope that makes sense.
