Fig. 67. A WORKING MODEL OF A BRITISH EXPRESS LOCOMOTIVE
Then again there are many machines that can be made of any size and which will work equally well. Fig. 67 is a scale model of a British express locomotive. It is 4 feet long and an exact scale model which can be fired up with coal and it will make a speed of 10 miles an hour.
A scale model of your invention, if it is a machine, or an electrical apparatus, when built by an expert model maker, makes a mighty pretty display and will never fail to attract attention wherever it may be shown.
Working Models.—A working model may be a scale model as you have seen or it may be a full sized machine or of any size between these limits.
When you have your invention past the drawing board and up to the shop bench by all means make a working model of it and if possible make it full size. This kind of a model is the proof you want that your invention will work when it is put to the test and by making a working model you will find lots of changes little and big that are needed and which when made will improve its operation wonderfully.
And however carefully you have worked out your invention on paper you will find that when you come to make a model, or have one made, you will have to change it not once but many times, that is if it is a machine in which a number of parts are made use of and you may have to re-design it and re-construct it several times.
For this reason it is a waste of money to build a fine appearing and costly model in the beginning but what you should do is to make one that will work without regard to its looks so that you can experiment with it, overhaul it, tear it down, build it up again and so on until you are satisfied with it and the results it produces, if such a thing is possible, before you even begin to talk to a patent attorney about applying for a patent on it.
Nearly every tyro inventor seems to believe that the only way to keep honest folks from stealing his invention is to apply for a patent on it immediately. You will remember I pointed out in the first chapter how to protect your first idea by signatures and affidavits and protection of this kind is just as good, and in my opinion just as safe, and in every way better than to rush off and apply for a patent and—though of course money is of no object—it is cheaper by at least $35.00.