Blakes Seacocks - re-grinding

[Georgio]

Having spent a very wet Sunday servicing all the seacocks, I have used fine grinding-paste on most to ensure a perfect taper and they now all work well.

However despite grinding there us still a little pitting on one of these, so my question is how much pitting is ok? I could easily grind this one further but it works fine as it is and the pitting is very minor. I should have taken a pic and posted...

Any thoughts?

 

[saltwater_gypsy]

A certain degree of pitting may be good news for grease retention!
Think of it as a percentage of the sealing surface and the result is probably tiny.

 

[samwise]

A little bit of pitting is inevitable. Big craters need more work. Slap on the grease and don't tighten down too hard and it should be fine. Don't forget to clean off all the grinding paste before you refit.

 

[ebbtide]

You'll know soon enough. Eventually no amount of grease will provide a seal without clamping down so hard that SWMBO won't be able to use it!
However, the timescale is around 50 years I believe.
(that's age of the bog not Her Indoors of course . . . )

 

[angelsson]

The Blakes are so well made, and as mentioned here have a lot of surface area and the % lost from pitting will be small.

I had one that was pitted a litte more than i thought was comfortable, but still not leaking, I fiiled the pits with solder, making sure of course when doing so the valve temp was high enough to make the bond with the lead good.
I then carefully took down the lead above the vave surface down to match the original shape.
Finally using some graphite grease mixed with the finest of powders gently bedded the valve back in. Finally fitting with grease as suggested.
I have checked the repair many times and it is still working perfectly without undue tightening when in use.

 

[Georgio]

Thanks all, I won't lose any sleep over it then. Will give it another session with the grinding paste next winter.

 

[Malish]

if you can fully de-grease the plug then pits can be filled with a dab of epoxy followed by some gentle fairing and a quick spin with the grinding paste

 

[Poignard]

I used epoxy thickened with graphite powder. It has lasted many years.

 

[Boots]

I agree with Saltwater's comment. I'm sure that part of the action of the grinding paste is form a rough enough surface to help retain the grease.