"neilish" wrote in message
oups.com...
hi i was doing some keyboard repairs at a school today and both my
desolder pumps stopped working - i determined that the cause was not a
blockage as usual but that it needed lubrication - i asked the janny
for some wd40 but he didnt have any but he suggested washing up liquid
- i put some on the piston and its working better than new - is this a
bad idea

No, introducing a non-perishing lubricant is a good idea IME, but I
personally wouldn't want to use washing up liquid.

will it eat away the rubber ?


Probably not, but it may 'gum' up causing sticking or drag. It is likely
to dry up fairly quickly because AFAIK washing up liquid is a water based
substance.

I can only speak for the neoprene washer style pumps, not the o-ring seal
variety-

I routinely apply a dollop of silicone grease (the clear lubricant stuff
*not* heatsink compound) to the barrel and piston of my solder suckers and
it decreases friction, improves the seal and gives a huge performance in
suction, even when the neoprene washer is already worn. It also drastically
increases the life of the seal/washer, I haven't changed the neoprene washer
in mine for ages.

The advantage of silicone grease is that it doesn't seem to affect the
neoprene washer at all, whereas mineral oils I'd guess may cause it to
disintegrate over time. I'm not sure if washing up liquid affects neoprene
or rubber though, or whether the o-ring seal type pumps use synthetic or
plain old rubber.

Dave