Drawings
Drawings
I feel that I am very bad with my drawings... This may sound very strange given the number of them that I have populated my web site with. However these are not "Technical Drawings" such as learned at school -but rather what I would call "Illustrational Drawings". There is no front/side/plan elevation assemblies and for me this works well. I have in my posession a drawing for a LBSC Baltic tank locomotive from XLIST plans ltd -it is a full scale drawing of a Gauge 3 loco -there are no dimensions anywhere and it is as it would have been drawn by the draughtsman.
The internet abounds with drawings for locos and rolling stock -however you are pretty much at the mercy of the person who did the original scanning -or the compression factor used... Fairly old drawing will be stored as a GIF file and these are normally fairly robust and can take a lot of hammer in the storage dept before the GIF degrades. The more modern files will be stored as JPEGs and these are to be viewed with caution. JPEG is a "lossy" format and can be "compressed to death", your new drawing might be a minefield of black squares... There ARE a few places where you can find drawings in the "proper" format e.g. AutoCad files -but I would advise people to avoid these as unless you have the correct viewer -things can go amiss. "Whip" used to available free of charge from AutoDesk -but this has now ceased... You may come across people who have very nicely created drawings and saved them as PNG files -these are really the cream of the crop!!!
Do I use exotic software and computer systems to do my drawings with -the answer is both yes -and no(!)
My main computer is a 192Mb Apple 8600 running a PPC at 180Mhz with a Radius Thunder video card and a Radius 19 inch colour monitor -it runs Mac OS 9.1. This wonderful machine dates from 1996...
Most of my drawing start out as "doodles" on sheets of A4 paper -some of them might use my technical drawing tools from my 'o' level days -but this is simply a start. If you examine the drawings you will see how I start out...
So, lets start at the beginning:
Here we have a Kitson Meyer of the "Type 2" variety, there weren't that many of them made, (only4!), so getting any photo to work from is a bonus.
Now as you can see this picture from the web suffers from the typical "compressed to death" JPEG problem along with the fact that it was an early photographic emulsion and time has degraded it -even before the scanner touched it. The rear of the loco shows C G R -which means Cape Govt Railways. The authority on Kitson Meyers is a book by Donald Binns called "Kitson Meyer Articulated Locomotives" and is published by "Trackside". A flip through the lists on page18 gives a bullseye on the loco. This MUST be works number 4197 built in 1903. There is actually a section on this loco in the book -but I will carry on the exercise.
There are several photographic packages that will do the following trick -and sharpen your image. This was done using "Soap". All that now seems to have happened is that the drawing is darker -what it has done is limit the number of greys to produce a more refined pallette. The shape of the steam dome is now apparrant and the roof line is discernible. HOWEVER, some of the small detail has been removed, the handrails on the tender are now less obvious for example.
The next step (for me) would be to print it out on graph paper and try draw in by hand the outlines of the various parts of the locomotive to gain a working edge.
Well after a few minutes work with the "Paint" aspect of Appleworks I have the drawing below. Note how just outlining some parts of the photo can cause it to "snap into focus". The front steam cylinder has been outlined while the rear one has not -similarly the tender is mostly untouched.
Now it is possible to begin the rough measurement of your photo. One of the aspects that you have to remember is that the extremities of the photo will be fore shortened and only measurements taken from very nearly directly ahead can really be treated as "reliable"...
The distance between the driving wheels shown at "A" is possibly the best one to go for -for this measurement. Examine the difference between the wheels on the front bogie and you will see the fore shortening effect in operation. Similarly the tender wheel spacing at "B" will be too small. The distance "C" has to be a maximum of 13 feet, (CAPE gauge loading), this enables us to do a rough guesstimate of "D"...
If you load each of the pictures above into differing "tabs" of your browser you will be able to see the steps sequentially!
Sometimes you can be lucky and find a line drawing in a book and this has a scale bar at the bottom of it. Then it is simply a process of working out your scale factor from the drawing to your "full scale model" size. As stated I use Appleworks and I simply draw the lines and then measure them on the ruler bar. The following drawing is from a book printed in 1924. Since I knew the size of the drawing and the size the model would have to be, (it is a Gauge 3 model) thus it is 13.5mm to the foot. In either case I would recommend that you print out the full scale model drawing and stick it to your work shop wall while you are working. Not only is this a handy reference but also an aide memoire that you can scribble part numbers onto, (or suitable sources of bits that can be made to work!)
