Occasionally we have forum opinions expressed on lubricants and many of us have a favorite. I was going through some workbench "stuff" and realized I had accumulated three different oil type lubricants: woodland scenic light oil, MTH oil, and 5w-30 synthetic. 5w-30 synthetic is often mentioned as the lifetime supply option and as good as anything in the high priced 2oz. containers.
The idea: Why not try a half-baked experiment to see if any differences can be detected? The idea is to put an equal oil drop (out of identical droppers) on 20lb copy/graph paper and see how the lubricant penetrates the paper. Repeat three times and measure. The assumption is these are all capable lubricants for our simple applications, maybe "penetration" might be the difference. One "creeps" better than the others perhaps?
Results: Within the limits of my measurement skills, there is minimal difference in these oils and their penetration using paper. I thought the WS light oil or MTH would be less viscous and create a larger circle than the 5w-30, but you can see that is very minimal if at all. Whatever this means, one detail difference to notice in the picture, the 5w-30 oil dot is less translucent (darker) per the camera.
(Disclaimer: this is not a gauge R&R study or a study in significant digits. 
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| Diameter of oil drop (inches) | |||
| drop | WS light machine oil | MTH oil | 5w-30 synthetic |
| 1 | 1.01 | 1.01 | 0.98 |
| 2 | 1.01 | 1 | 1.01 |
| 3 | 1.02 | 0.98 | 0.99 |
| average | 1.013 | 0.997 | 0.993 |
