Originally Posted by
iiipopes
I agree. WD-40 is a water displacer, not a lubricant. Now, obviously, water displacement on valve caps is a legitimate concern, but this isn't the application for WD-40.
Traditional slide grease is. ...
Yes, but you need to take a bit of care in what you mean by "traditional slide grease" and how long you leave it on before removing the caps and re-lubing. For about 20 years I used anhydrous lanolin as "slide grease", and it's still by second favorite stuff for this purpose (Dow-Corning High Vacuum silicone grease is what I use now). But you don't want to put it on and then leave it there for years. It and other "traditional" greases may dry out and harden. So just beware of that if you don't have regular maintenance intervals. This isn't a problem with the more modern "greases" that contain silicone and other synthetic materials -- though they have other potential problems if you use too much of them.
Gary Merrill
Wessex EEb Bass tuba (DW 3XL or 2XL)
Mack Brass Compensating Euph (DE N106, Euph J, J9 euph)
Amati Oval Euph (DE 104, Euph J, J6 euph)
1924 Buescher 3-valve Eb tuba (with std US receiver), Kelly 25
Schiller American Heritage 7B clone bass trombone (DE LB K/K10/112/14 Lexan, Brass Ark MV50R)
1947 Olds "Standard" trombone (Olds #3)