[sdiy] Hammond on ebay, broken

[Magnus Danielson]

From: "Roy J. Tellason" <rtellason at verizon.net>
Subject: Re: [sdiy] Hammond on ebay, broken
Date: Fri, 16 Nov 2007 21:09:28 -0500
Message-ID: <200711162109.28285.rtellason at verizon.net>

> On Friday 16 November 2007 20:10, mike ruberto wrote:
> > Now my tone generator is starting to seize up. I suspect the oil
> > capillaries have gotten gummed up. I have been putting this off for
> > some time because it is a filthy oily mess in there.
> 
> I did a service call one time on a unit that was like that -- you'd turn it on 
> and the generator wouldn't spin up at all.  It'd been sitting for a really 
> long period of time,  I think something like seven years?
> 
> Anyhow,  what happenes there is that the old oil has lighter fractions that 
> evaporate,  while the heavier stuff stays behind.
> 
> What I ended up doing was adding some fresh oil,  and then turning it over by 
> hand,  over a period of time,  until it would start when the switch was 
> turned on.  Then I told the customer to leave it on and run for a while,  
> which allowed the new oil to get to where it needed to be...

Indeed. What you should have done was to remove the old oil. That is however a
more elaborate process, so adding new and rubbing it in will do for now. If you
think of what that process does in the long run, a propper clean out every now
and then seems like a good idea. Solving the old oil out with isopropanol and
let it dry out and then add fresh oil. Isopropanol dries out quickly on flat
surfaces, but it take some time in the mechanics, so a propper dryout is
needed. You want the isoprop gone before you add new oil since it will slip out
too quickly if the isoprop is still there. You want to be carefull with the
gears in the unoiled condition.

If you go for not cleaning out the old oil like above, you would have to add
new oil in several runs and let it work in on the old oil. Each turn you would
reduce the amount of old thick oil but it is not a very efficient process.

Cheers,
Magnus