Thread: Lapping my coti (taking for ever)

I haven't used this coti too much but decided to run a pencil across it to find it needed a good lapping. I'm down to the last spot as you can see in the pict. a little dip there and it's been a couple thousand laps and still not done.
My other coti lapped fairly well but this one is killer. I'm using a 1k dmt.

I don't have much experience with these stones can someone tell me if this is normal?

Make sure your lapping it under running water, where the water can prevent the stone from sticking,,, also do small circles from North to south, vise versa, not just straight strokes,,,, don't keep your lapping hand on the same end of the stone all the time,,, spin the stone around and grip the other end,,, do this switch a lot. Reason--- you will always be putting more pressure on the end where your hand is at,,, this causes one end to lap more than the other.

Yes it's normal that a coticule can be that worn.

Now STOP LAPPING.

Your coticule does not need to be completely flat. Put that low spot on the opposite side of your honing hand and you will be fine. If you remove all the rest of the coticule needed to get it completely flat, then you will be wasting a lot of perfectly good coticule.

You are not using enough grit. I usually use a 325, 400 or 140 if it really is out of flat. But as said, it does not need to be perfectly flat, it is up to you.

A piece of 220 or 320 wet and dry will get you there quickly then smooth with the 1K.

Followed this and now it's flat Thanks! Actually the DMT was 1200k

Originally Posted by Hirlau

Make sure your lapping it under running water, where the water can prevent the stone from sticking,,, also do small circles from North to south, vise versa, not just straight strokes,,,, don't keep your lapping hand on the same end of the stone all the time,,, spin the stone around and grip the other end,,, do this switch a lot. Reason--- you will always be putting more pressure on the end where your hand is at,,, this causes one end to lap more than the other.

Originally Posted by daverojo77

Followed this and now it's flat Thanks! Actually the DMT was 1200k

More likely 1200 grit. 1200k would be wicked fine!

Some Coticules are more difficult to lap. The last one I bought is a hard stone and takes at least twice as long to lap. Like others have said your stone is flat enough for now. It will work itself out over the next couple of times you need to lap it.

I've found that 600 grit wet/dry paper laps Coticules quickly and leaves the stone smooth (a slurry stone will smooth it further if you have one).

Hey Dave can you give us a side shot of that bad boy?

The thing is, with lapping you flatten the area around the low parts. Lots of stone there.

Sorry for being Captain Obvious, but I once forgot that myself.

And I'm with Ron here: absolute flatness is not necessary. Visual flatness for most of the hone will do.

Originally Posted by S0LITARYS0LDIER

Hey Dave can you give us a side shot of that bad boy?