Mellowing a Diamond Plate

[silverlifter]

I purchased an 800 grit Diamond plate from 1Stone to lap with, but when I use it on my finishing stones, it leaves small scratches. I tried wearing it a little by running the haft of a screwdriver over it several times, but it does not appear to have made much difference.

1. Should I worry about these scratches? My OCD has forced me to buff them out with a progression of finer stones, but I am getting tired of doing that every time I lap one of these stones.

2. Is there a better way to "mellow" a plate so that it can still efectlively lap, but not leave these random scratches?

 

[Legion]

Use it to hog metal off knives, and it will smooth some.

Hard stones like washita will certainly do it, but probably more than you want.

Depending on the stone, light scratches from a 800 diamond plate are unlikely to effect the performance.

 

[rbscebu]

I do a few laps with a meat cleaver on my diamond plates before their first use. Make sure you cover the whole surface of the diamond plate. Works fine for me.

 

[silverlifter]

Thanks! I'll take one of my old kitchen knives to it and see how it fares.

 

[rbscebu]

Use plenty of pressure. You are trying to knock off those diamonds that are sitting too proud of the surface. You won't damage the diamonds that matter.

 

[Gamma]

A lot of times people use too much pressure to lap stones and that will leave marks regardless of how worn the plate is.
Start there... then evaluate the marks.
Are they felt or just visual.

Which stones?
A 12 Super Stone - not a problem, they self-heal with a few passes.

If felt - prob best to clear them but first determine if they interfering with honing somehow.
Qualify the interference objectively.

If only visual, you can probably clear them with fine w/d paper but you most likely don't need to.

Lets say I have a Translucent ark, I always finish on 600x w/d anyway so that clears any lines.
But - lets say I used a diamond plate and there are lines... I determine if I can feel them and to what extent. Sometimes honing leaves marks in some Trans/SB Arks - my touch is light so those marks don't matter. After a while I clear them just for the visual aesthetic though. If someone was putting pressure on the stone, the marks could be deeper and if felt I would relieve them with a session on SIC followed by final finish on 600x w/d.

A lot depends on the stone in question, and whether or not the marks are invasive.

A buncha years ago I got away from the 'forced' wearing of diamond plates by 'running hard steel' over them. I find the plates will work better and last longer when they are just used normally with care being taken to use the plate's surface as evenly as possible.
Many times guys miss the edges of the diamond plate when lapping then they wind up with strips that are proud of the center and the plate becomes problematic. This is where figure 8 lapping patterns help but to be honest I don't use them too often.
Lapping Arks will tame an aggressive diamond plate but they really wear diamonds quickly. Too fast actually. A softer Washita might not be so hard on them but anything harder than that gets lapped differently. I usually use SIC for stones like Arks, Charns, LLyns, Chalcedony, Flints, Cherts, etc.

 

[Mr Kooby Shemayrew]

I purchased an 800 grit Diamond plate from 1Stone to lap with, but when I use it on my finishing stones, it leaves small scratches. I tried wearing it a little by running the haft of a screwdriver over it several times, but it does not appear to have made much difference.

1. Should I worry about these scratches? My OCD has forced me to buff them out with a progression of finer stones, but I am getting tired of doing that every time I lap one of these stones.

2. Is there a better way to "mellow" a plate so that it can still efectlively lap, but not leave these random scratches?

So when diamond plates are made there is a bunch of manufacturing materials including loose diamond bits *stuck* to the plate. This junk will naturally wear off. If you’re sharpening knives, it takes about 20 sharpenings to get it off.

Next, proper break in of a diamond plate. Imagine the little diamond bits are all formed different ways in different shapes. Many will have edges that stick out and other weaknesses. Brands other than Atoma have the added issue of the diamonds being imbedded at a wide range of depths into the substrate base. It is important to knock these weak edges off the diamonds to keep as much of the larger body intact and stuck / imbedded into the plate. Personally I like to use a round flat stainless steel plumbing cap. Use a lubricant and rub it very gently in circular motions. This will knock off the most fragile pieces first. Wash and brush the plate. Repeat with progressively more pressure. It will still take 10 to 20 knives to fully break it in but doing the initial break in like this protects more of the diamonds.

I have a 150/600 diamond plate. When used for lapping and flattening a stone the 150 side does not leave scratches but the 600 does. Normally I will use the 150 then the 600 then the 150 again to take out some of the scratches. Density - spacing of the grit is the cause of a lot of scratches. Higher grit or smaller grit does not mean it won’t scratch a stone.

I use a Ez-lap pocket stone for raising a slurry. This stone is particularly good at raising a slurry but keeping the stones surface in good shape. I also use it for removing scratches from other more aggressive diamond plates. This stone is particularly inexpensive and I highly recommend it. They do not say what grit rating it is though. I believe they do make them in larger sizes but I haven’t used any yet.

 

[alex1921]

Last diamond plate I got is from Shapton, the rest are Atomas.
Never mellowed them. They work fine.