Re: [TUHS] the distinct smell of light machine oil, was Re: TUHS Digest, Vol 33, Issue 7

[Pete Turnbull <pete@dunnington.plus.com>]

On 09/08/2018 15:15, Derek Fawcus wrote:
> On Thu, Aug 09, 2018 at 09:31:39AM -0400, Clem Cole wrote:
>> Hmmrrph.... Youngsters...    WD40 is silcon based.
> 
> I didn't know that; never I checked the can; but yeah a distinctive smell...

Ordinary WD40 is NOT silicone based (obNitPick: note the 'e': not 
silicon, which is a hard crystalline substance).  There is a 
"specialist" silicone-based version but ordinary WD40 is hydrocarbon 
based, being a mixture of light paraffin (naptha to transpondians, ie 
the stuff that's used as a solvent or fuel) and a paraffin wax, as 
stated in the manufacturer's official MSDS document.

The characteristic smell is largely from an aromatic hydrocarbon additive.

>> Real "3 in One" oil
>> (came in a small can) is light machine oil but you can still get it:
> 
> Yup, useful on bike chains and oilstones (as in sharpening chisels and planes).

And not much else, because like a lot of simple hydrocarbon oils 
developed half a century or more ago, it oxidises to a gummy substance.

The Teletype manual definitely doesn't suggest 3-in-One oil and some 
sources suggest it's too thick anyway.  The manual in front of me 
specifies two Western Electric part numbers for oil and grease.  It's 
been discussed more than once on the Greenkeys list, and there's a 
useful page listing modern equivalents at Doug Jones' page:
https://homepage.cs.uiowa.edu/~jones/pdp8/UI-8/ks7470oil.shtml

-- 
Pete
Pete Turnbull