Time index below for easy navigation. Product links at the end.
(SORRY ABOUT THE HUM... as you can see, I was a moron and thought I was recording into a different camera and mic, so I had to crank up the audio, hence the hum).
This video became more in-depth than I had hoped, but feel free to skip around using the time index. Not exactly a review: basically I wanted to disassemble and examine the budget linear rail that is available from banggood, aliexpress, amazon, etc. Subjects examined are: lubrication, corrosion prevention, disassembly/re-assembly, alternatives, oil vs grease, etc.

2:10 intro and linear guide rail vs v-slot
11:32 cart disassembly and how-to
13:45 machining quality and scope pics
15:34 bearing measurement and spec
19:40 general lubrication rules
23:40 linear rail viscosity note
28:53 household solvent/degreaser overview
32:31 grease overview
35:47 oils overview
36:58 grease experiment and how-to
36:58 TL;DR oil experiment and how-to
43:56 TL;DR initial results and noise testing
45:48 TL;DR do they suck?

Banggood linear rail (cheaper, slower shipping)
https://www.banggood.com/custlink/v33...

linear rail (more expensive, faster shipping, slightly higher quality)
https://amzn.to/2HVGRhT

3/32" G25 ball bearings
https://amzn.to/2WN9scI

Super lube (small tube for testing)
https://amzn.to/2Bk3F55

3-in-1 oil
https://amzn.to/2Sx9UfH

WD-40 small bottle (for solvent or rinsing after solvent)
https://amzn.to/2Dc9PEG

Tri-flow (synthetic oil + teflon)
https://amzn.to/2BmKs31

Heavy Silicone spray (prevent rail corrosion)
https://amzn.to/2WOjomq

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