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LyleM
12-17-2010, 07:45 PM
I have several little motors i'd like to make, however they are very small. Can anyone point me to something that explains how to upscale things? Thanks

darryl
12-17-2010, 08:57 PM
There's a function in mathematics called multiplication- I don't know if you've heard of it-

Sorry, no disrespect intended. You might have to be more specific.

LyleM
12-17-2010, 09:10 PM
If you didn't mean any disrespect then don't post it, I found what i was after in a Rudy Kouhoupt video.

brian Rupnow
12-17-2010, 09:18 PM
Lyle--depending on what you want to build, I have published a couple of articles in Home Shop Machinist that are a bit larger than Elmer Verbourgs engine designs. In Sept. 2009 I did an article on a beam style steam engine, and this month carries my design for a 5 cylinder radial air/steam engine. I too find it very difficult to machine things that are almost too small to see without a magnifying glass. ---Brian

Stepside
12-17-2010, 09:31 PM
I first use CAD to draw the part full size. When I print the drawing 1 inch equals 1 inch I can see if the parts are too small to be much fun. Printing in different scales helps me determine what size to use. The next step is to determine the sizes of the fasteners, the bearings and other material standards. I can then either slightly change the scale or I can modify the drawing. When done I have a fully dimensioned drawing and I have built the part in my mind.

If the design is one of my own, I still use the same proceedure.

SGW
12-17-2010, 09:45 PM
It's easier to scale down safely than it is to scale up safely. Scaling down, strength relative to size increases. Scaling up, it's the opposite. This would be of particular concern in a boiler.

For simple models, everything is probably over-engineered so much that you don't need to worry, but just realize that it is potentially more complicated than simple multiplication.

LyleM
12-17-2010, 09:51 PM
Thanks for replies, that was my thought, it has to be much more complicated than just doubling the size of everything. Like if i increase the bore here, if its not proportion the rest of engine it will fail.

Bill736
12-17-2010, 10:44 PM
The lack of proportional scaling when enlarging is an interesting subject that is seen in nature as well as man made items. The bone structures of large animals, the difference in quickness between lightweight and heavyweight boxers, and the design of large pressure vessels are but a few examples.
A detailed study of such phenomena might be enlightening indeed.

macona
12-17-2010, 11:06 PM
If you are building internal combustion engines I understand that things also change since now your compression is different and a few other things. Nothing that cant be worked out though.