From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Letter to Claude Johnson regarding the lubrication of a sphere, outlining objections to using a pressure gun due to the likely use of incorrect grease and potential for grit contamination.
| Identifier | ExFiles\Box 16\1\ Scan092 | |
| Date | 28th July 1923 | |
| Oy9-W-72823 July 28, 1923. Mr. Claude Johnson, Rolls-Royce, Limited, London, England. (Copy for attention of Mr. Royce) Mr. Platford) Mr. Hives ✓) Dear Sir: Re Lubrication of Sphere COPY With reference to the lubrication of the sphere, we have discussed several times the possibility of piping the sphere to the side of the frame and fitting a nipple for a pressure gun, and a similar nipple on the centre bearing of the torque tube as done by England, and our objections are as follows-- (1) The probable use of cup grease in many of the pressure guns. (2) The introduction of grit into the inside of the sphere and the middle torque tube bearing. (3) The long time and effort necessary to introduce one pressure-gun full of gear oil past the restricted nipple in cold weather. (1) - Cup Grease We call for the use of 600-W (gear oil) or the heavier "Valvoline Heavy" in the pressure gun, but we know that many drivers insist on using ordinary cup grease of any brand in the gun, since it has the advantage of not dripping from the parts lubricated and being easy to squeeze through the pressure nipples in all weathers. This does no harm to shackles, etc., except that if left in too long it dries up and blocks the oil holes. It is quite incapable of lubricating the universal joint, however. Also, it tends to go rancid, liberating acids, and therefore should not be permitted to get to any point where there is a ball bearing, for fear of corrosion. (2) - Grit We know that in filling the pressure gun with grease it is very easy to get grit into it, and whether used with grease or oil the grit from the nipple is likely to be introduced. | ||