Recent Changes - Search:

G3 Wiki Read First

* HomePage

* What is Gauge 3?

How To Contribute Content

Contact Administrator


LATEST UPDATES:

* Build GWR dia. AA11 "Toad" from a kit

* Machining Steel Wheels

* Thermodynamics 201

Drawings

These are the most important part of G3 model making. Unfortunately the quality of some of the original drawings can only be described as DIRE and many of the ones that I own and have used have had to be re-drafted or manipulated digitally to get a workable drawing. The reason for this is simple and complex.... The original makers of the drawings assumed that you knew what you were doing. I have an LBSC plan for a steam cylinder that does not show any steam ports or steam chest ports. HG was not much better as he assumed that you would employ already existing equipment to do the job.

Beware of the A2 sheet of paper that says "Plans Full Size" because they won't be. They will have been originally printed on Double Elephant size paper which is larger. It has become common practice to use "scale to page size" option on laser printed documents. Thus all the sheets are A2 but not to full scale.

Modern drawings are of a higher standard but the draftsman may have mixed; fractional imperial, decimal imperial, metric, and ME thread values into the drawing.

Depending on your age and upbringing you may feel the need to convert some or all of the dimensions into values you can "see". Converting Fractional Imperial into Decimal Imperial is quite easy, however doing either of these to metric can be quite challenging -despite the fact that most materials sold nowadays are in metric dimensions.


You may be forced to produce your own drawings for your model based on a collection of photographs and (possibly) draft office file drawings from the builder.

This hopefully will give you some idea...

This is the NER 13, a prototype electric locomotive designed by Sir Vincent Raven. It was at the time very futuristic and incredibly powerful. It featured highly advanced thinking such as quill drive, bogie locking for stability at speed and variable resistor switching for power control.


Blue Print

Several photographs exist of this loco but these two are the basis of all the drawings. The first is a side shot showing the entire loco, buffer to buffer.


Side Profile

The shot was taken from a distance, thus there would be little spherical aberration causing the centre to bulge out. The second is a 3/4 shot again from a distance showing the Number 2 end (with the moustache), and the sides of the loco.


3/4 Profile

How to begin?

Your researches should have given you some basic facts such as height and length and the wheel sizes. The next step is to print out, at G3 scale if possible, the shot and then sit down with a ruler and dividers. Gradually you annotate the drawing with dimensions. The next step is to make your own drawing, whether you use pencil and paper or a mouse depends on personal preferences (I doodle on a draft tablet then mouse it on the computer).

There are several "CAD" programs around but I prefer to use a more simple "Draw" program. Which you use is again down to personal preferences, however the drawing below was done using "Open Office". (replaces page).

If you are going to produce a drawing for Laser cutting then you HAVE to produce a file in the AutoCad formats DWG or DXF. It is possible to export DWG and DXF format files to PDF. I normally do this when I e-mail the drawings to the laser cutter as this shows what I want and I can see the drawings without having to load my CAD program. Which CAD program you use is down to the Operating System of your computer. Most Windows PCs can handle AutoCAD and TurboCAD. If you have a MAC OSX system lower than Lion, then TurboCAD is your only option. Linux and UNIX based systems usually use dedicated commercial programs. The drawing below is an example of a converted DWG to PNG file produced on an iMAC using Snow Leopard and TurboCAD. (replaces page).

You may be the proud owner of a genuine drafts office assembly drawing that has suffered from years of neglect, or a scan nicely sent to you of one.... Normally the page will be covered with speckles and stains and some of the ink will have faded. So, how do you "rescue" the drawing to make it usable as a design document for your plans? The standard method of image rescue is a program called "GIMP" which is free. This enables you manipulate the image at up to 800% resolution and rub out or rewrite lines. This will take you a great deal of time but it is worth it in the end as you will have a master to work from. The image below is the "after" of the process. The original had a coffee cup ring stain, a few greasy thumb prints and what could be a sandwich order(?) scribbled on it. (replaces page).

This is a typical "before".... (replaces page).


Edit - History - Print - Recent Changes - Search
Page last modified on February 12, 2018, at 05:21 PM