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I'm new to the world of lapping & am wondering if some of you could give me tips/recommendations/etc.

I recently purchased some Talley Lightweight *Aluminum* rings and a Sinclair 1" lapping kit (came w/ the lapping rod, handle, and the compound - which I believe was 280-grit).

I began lapping the rings & it looked like I got a nice pattern, with about 80% contact. I cleaned up the rings w/ rubbing alcohol & wiped all (or so I thought) the residue away. The scope fit *really* nice into the rings but then the problems surfaced. It appears the some of the compound/shavings stuck around (maybe in the pores?) and it scratched the crap out of the scope when I slid it back to adjust for the eye relief. I didn't have the rings tight at all. They left a silver "residue" in the finish of the scope.

Did I do something wrong w/ the lapping? Maybe you can't lap aluminum rings b/c they hold on to the compound b/c it's harder than the aluminum? How do you clean these things up after lapping? Will this happen w/ steel rings?

Any tips/ideas are appreciated.

-robert

Sorry to hear about your problem. I've used the Sinclair rod and compound for years, and never had that happen. First thing I'd do is contact Sinclair. They have knowledgeable folks on staff, and great customer service.

Paul

I have a Sinclair Lapping Bar which I've used for many ring lapping jobs. I haven't experienced the problem you mention. I have both the 1" and 30mm lapping bars, and lapped about two dozen sets of rings, for myself and friends.
To be honest, and too the point, it sounds like the rings weren't completely clean after the lap job.
Sinclair's lapping compound is Aluminum Oxide, so there could have been no compound embedded in the rings themselves during lapping, which a Silicone Carbide compound will do, and eventually grind the finish off the scope tube.
I would take a good degreaser, or carburetor cleaner, and clean the rings again. See if that does the trick. Use tooth picks, paper towells, que-tips, pipe cleaners and old tooth brushes to get into all of the nooks and crannies to get any compound in those areas cleaned out.
Don

Thanks for the ideas/comments. I scrubbed it w/ rubbing alcohol, paper towels, and q-tips. The paper towels weren't getting "grey" anymore - they were staying totally white. A few people on another board said they've never heard of lapping aluminum rings. Possibly that was one part of the problem? I thought about using carb cleaner or something harsh but didn't want to as I didn't know how to keep it off other parts of the rifle (soaking down in cracks/etc.). Oh well, I guess it's a live & learn situation.

I've lapped aluminum rings without problem. I just use a steel one inch bar and fine lapping compound. Sounds to me like you had some lapping compound somewhere and were lapping your scope. That would be novel way of going about it. Some aluminum black or a felt tip might hide the scratches in the scope somewhat.

I don't think rubbing alcohol will do the job well enough.
Gun scrubber on q-tips, etc will however. Lots of places for the black junk left from lapping to hide. Acetone should do the job too. I use Rig 3, which isn't available now, but I have some left. It is a first rate degreaser, and has done the clean-up perfectly.
I've lapped lots of Aluminum rings also. It's highly recommended to do them as well as steel rings. It's the only way to get a good fit for the scope. I have bedded scopes in the rings after lapping for a 100% fit, using JB Weld, like you bed a barrel and action in a stock. Kind of overkill, but no chance for ring marks on the scope that way, and zero stress on the scope tube also.
Don

I clean up after lapping with wd 40 and paper towels then clean with cotton patch with Remington oil till patches are not showing any dirt

For those that might be interested, Sinclair is offering their 1" ring lapping rod on sale for $10.50. Just an FYI/FWIW