06-26-2021, 05:27 AM
(06-25-2021, 10:07 AM)Stichill_imp Wrote:(06-22-2021, 01:57 AM)2017EX_imp Wrote: I think michael1954 has the best solution, an Allen or Torx counter sunk head screw of the correct metric size in steel. I have used stainless in a few places, but when I do, am careful to use a sparing amount of anti seize on the threads. I dont think I would use stainless in this application because not only can stainless gall, causing the fastener to seize, but also because stainless alloy has lower torque and shear specs than steel. I would be interested to see the eBay listing michael1954 used for his screws.
How much torque and shear strength does it really need to retain a cover?
Galling tends to be a problem with similar metals in contact with each other. As long as one is harder than the other, galling shouldn’t be an issue.
How much torque and shear strength does it really need to retain a cover?
Galling tends to be a problem with similar metals in contact with each other. As long as one is harder than the other, galling shouldn’t be an issue.
You are correct Sir, point taken. The Book calls for 1.1 ft-lbs on those master cylinder cap screws. None of my torque wrenches go that low. I had thought my inch pound wrench would go low enough doing the conversion, but no such luck, 1.1 ft-lbs is 13.2 inch pounds. Good and snug by hand is the result, at which point galling and shear strength are not issues as you pointed out. My bad, as my head got stuck between "in general", and this particular application.
Galling can happen between similar and dissimilar metals, but stainless titanium, and aluminum are more susceptible that others. I have ordered stainless Torx screws for my CB and Monkey as they both take the same size, M4x12. Oddly enough I could not find that size in steel. I did stumble on an interesting article on how Torx was less likely to strip out than Allen. When I install them, I will be using anti-seize sparingly on the threads, and possibly a thin film on the head taper. I have the proper JIS screw driver, but I think the Torx is a more secure solution.