Thread: lapping with 6 inch DMTs?

I'm interested in buying a DMT for lapping a Belgian Coticule (which I also haven't bought yet.....) but the 8" models are really expensive over here. The 6" ones are affordable however.

Will I have any problems using the smaller stone to lap?

Also, I think it might be easier to do the lapping upside down to how it is shown in the wiki, ie. coticule on the bottom, lapping stone being moved in circular motions from the top. Would that work OK?

Forgive the noobish questions pls

Cheers.

I've lapped a bunch of stones with a 6 inch DMT, ranging from small barber hones to at 8 inch C12K. No issues with the DMT being smaller, thought I'd assume an 8 inch DMT would make it faster.

I have not found any difference with regards to which goes on top. I switch it up depending on which is easier to hold/move.

I use the 8" plates to lap all my stones, they stay flat as they are a milled 1/4"+ plate of steel. Other DMT sizes are plastic based and may cause slight warping with trying to flatten some stones. Just depends on the plat you are looking to use.

My 6 inch is definitely not plastic based.

I am aware that DMT makes a plastic based hone that has the holes for swarf, but I don't believe that all the 6 inch hones are of this model.

DMT Dia-Sharp 6x2x1/4 in. Diamond Plates

Looks solid to me.

Edit: Littlesilver (below) has a good point. I don't know that they make a 6 inch coarse enough for lapping stones.Wet/dry sand paper on a flat surface will work very well. None of my coticules or BBW's took more than a few minutes to lap on sand paper.

I wouldn't waste my money on a DMT just to lap hones. There are some cheap copies around that you could use though. Or use wet'n'dry sandpaper on a flat wet surface. I use 300 grit wet'n'dry on a slab under a running tap.
I have a DMT 1200 6x2 it is great for bevel setting but would wear out (I'm sure) lapping hones.
I paid about £25 all in for the 6x2 DMT
There are 2 types of DMT hones, continous=looks like a slab of metal and there is the other type that looks like a cheese grater.

I started out with the 8" continuous D8C and it has worked very well. Whichever you get doing it under the tap with the water trickling down is good for the hone and the plate. Marcus is right though about sandpaper. If all I had to lap was one coticule I could get by with that. Coticules don't need to be lapped as often as polymer based synthetics unless you're doing a lot of razors.

I was considering sandpaper, but I'm haveing trouble finding a flat surface. I've put a straight edge to a couple of tables, and the kitchen counter top, but none are completely flat...maybe I'm being a bit too particular, just how flat does it have to be?

I've seen glass mentioned, but unless I take my bedroom window off it's hinges that's a no go too

There is a tutorial here in the SRP Wiki that goes over some of this. A lot of guys seem to use granite tiles that you can buy at a Home Depot here in the USA. I'm sure you have Home Depot or the equivalent in UK ? Josh, the fellow who wrote the tutorial worked on the counter top until he got the diamond plate and moved to the sink. As far as how flat, the flatter the better.

Our equivalent's of Home Depot are B&Q, Wicks, Home Base, Focus and Screw-Fix. These are nation wide, but there are better smaller outfits too.