My first Automag

[Watcher]

I've had bad experiances with 3n1 in various other projects.

It may depend on the brand, but the 3n1 I used had petrolium distillates and those like to eat rubber, or otherwise o-rings... had a ruined pellet gun air resevoir or two before I realised that and now I won't touch the stuff.

[ManInBlack]

I think the air tool oil at Lowes should work fine.

[Spider-TW]

Urethane orings are annoyingly sensitive to lube. Most petroleum gun and multipurpose oils will harden them and turn them brown over a year or two. Synthetics do better. But lately I've been noticing some urethane orings looking a little green and they seem to be swelling a little. It's a good thing on the level 10, but bad on an on/off. It may just be the combination of lubes on some second hand parts. There's a few old forum threads on lube.

Generally, non-petroleum stuff that is slick and about the same viscosity as 3 in 1 is what you look for, except of course, auto-lube.