Thread: Lap Spyderco UF on DMT 8EE?

Originally Posted by Bruno

From what I've read so far, you'd need a large stack of sandpaper before your UF was flat, in which case a DMT8XX would be cheaper.

I did give sandpaper a try when I decided to lapp my UF, it's rely an waste of time IMHO, didn't do much, so get a DMT C if you decide to lapp it.

BTW, my UF works better for me after I lapped it, it may have something to do with removing the circular pattern on it, but I'm not sure.

I looked back at what Steven (Sticky) had said on the B&B thread I quoted above about the manufacturer's tolerance: 20 mils over the length of the stone (where did you get that number, Steven?). For comparison, 20lb printer paper is 4 mils thick, so that's like 5 sheets of printer paper. The variations I'm feeling are certainly less than that, I would guess 5-8 mils, so I think my stone is within manufacturer specs. However, the variations occur over short distances making little ridges on my stone.

So now my question is, do you think this is good enough for finishing the edge on a str8, or will it mess up my razor? I guess I'll have to just try it and see... Might be a good reason for folks considering what finishing stone to buy to go with a Chinese 12k + lapping stone instead of the Spyderco UF.

Originally Posted by BurnBeGone

I looked back at what Steven (Sticky) had said on the B&B thread I quoted above about the manufacturer's tolerance: 20 mils over the length of the stone (where did you get that number, Steven?). For comparison, 20lb printer paper is 4 mils thick, so that's like 5 sheets of printer paper. The variations I'm feeling are certainly less than that, I would guess 5-8 mils, so I think my stone is within manufacturer specs. However, the variations occur over short distances making little ridges on my stone.

So now my question is, do you think this is good enough for finishing the edge on a str8, or will it mess up my razor? I guess I'll have to just try it and see... Might be a good reason for folks considering what finishing stone to buy to go with a Chinese 12k + lapping stone instead of the Spyderco UF.

The 20 thousandths of an inch is stated on a sheet included inside the UF's box (also in the M and F's box). Was in my purchases, anyway.

My stone was within manufacturer's specs, barely. It still wouldn't put a very good edge on my razors. The flyer in the box states " .020" of flatness over their 8" length ". It does not say PER 8 inch. In inspection terms that means it can be .020 difference w/in a 1 inch length as long as the ENTIRE hone is w/in .020 overall; as opposed to something like " .005 per 2 inches ".

After lapping, my UF performs acceptably. Before lapping, it did not.

Try sharpening without lapping it first. If it doesn't perform acceptably, either lap it or return it to Spyderco. In my opinion the Spyderco is just as good as the Chinese 12k, in terms of practical razor sharpening ability (meaning ability to give you an acceptable shaving result). Some users do not need to lap the Spyderco. Luck of the draw. The Chinese 12k and the UF both seem to come from the factory with different levels of surface flatness, which is rather normal for most manufactured items. Personally, I lap every hone I get (except DMT's), whether it's for razors or knives.

Good luck either way.

EDIT: I'm with bjorn, avoid the sandpaper on the UF or Chinese. Sandpaper would take forever. DMT's are more cost-effective and faster by far.

it took me a while using 3m 400 ahd 600 grit wet paper,but it is flat

Did it take many sheets?

more than i care to mention