Best way to remove lapping compound?

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I recently lapped a set of Talley LWT 1pc rings and for the life of me can not get the lapping compound (the compound that comes with the Plenty o Patches lapping bar) out of the ring threads. I've used brake cleaner and WD40, neither of which removes the compound from the threads in the rings. I tried chasing threads with the screws but there's still a film no matter what, I even managed to break a screw off when ignoring the problem and attempting to mount the scope with the dirty threads :redface:
 
I have no experience with tally's products but most are lapping compounds are usually oil based. Like disolves like, so if oil based solvents (brake clean, wd-40) didnt disolve it, I would try soap and water. might work, might not, but its worth a shot.

Brad
 
Maybe running a tap through would clear it.
Might be the only way if the abrasive has embedded in the threads.
 
Give them a bath in a varsol tank, then hit 'em with compressed air. Nothing like a little 120 psi to get the crap moveing. If I remember right the threads are 6-40, you may need to chase the threads with a tap.
 
I'm assuming that you've tried all the usual solvents such as spray brake cleaner or swishing around in a tank.

If this still leaves things gritty feeling then you've got troubles. The way that oil or wax bound abrasives work is that they dig into the softer of the two mating materials and grind away at the harder material. This is why cast iron is used as a lapping form for hard tool steels, brass is often used as a lapping form for milder steels and plastics can be used as a lapping form for brass or aluminium. Each of these softer lapping forms will allow the pressure to embed and hold the abrasive grit and turn the lapping form into a sort of grinding tool.

To remove the grit from something like aluminium rings you need to get something softer in there to grab the grit. For the saddles I'd suggest simply rubbing them aggresively with a plastic pot scrubber pad. The "wooly" sort, not the green Scotchbrite style. For the threaded holes I'd start with a bristle style pipe cleaner in a hand drill with some solvent so the bristles can sweep through the thread valleys and hopefully pick up the grit and hold it until removed. Repeat a few times with fresh pipe cleaners. Another option would be to cut up some wood sticks so they are able to hand turn QUITE EASILY into the holes and bite LIGHTLY into the threading. Again the wood will grab and hold the grit and remove it. Repeat with fresh slips of wood until the threads feel clean when you turn the screws in by finger.
 
Varsol, pipe cleaners/drill and 120psi cleaned up the majority of the compound in the thread ring/base, chasing the threads with a tap cleaned up the rest.

FYI - brake cleaner will remove the finish off Talley screws if allowed to soak for 3 days (at least they are shiny clean now).
 
It sounds like you have imbeded the compound in the threads [charged them like a lap would be charged] by trying to chase them with the screw.
Do what Tiriaq suggested and try and run the proper tap in there.
 
well, if its like buffing compound...(which can be difficult to remove... wd,brakeclean, etc don't work well) I use kerosene and a cotton rag...
 
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