Thread: My GDLP has issues...........................

Originally Posted by Russel Baldridge

30 seconds?!?!

That'd be impressive to see, slurry would be flying all over the place!

So the surface does not have a guarnteed flatness, then, only the backing material? Seems like a strange way of measuring flatness.

Glad to hear he is taking a personal interest in your case though, hope it turns out well.

I agree, when he "puts his shoulders into it", he must be reaming on the GDLP or the stone. I've never even come close to applying that much pressure. Now, if I get the GDLP back, I can look forward to an extra workout!

Yep, the float glass has that guaranteed flatness. Harrelson said even if the GDLP surface is lapped/refreshed, with .5 flat for the glass, the actual but undetermined flatness of the GDLP surface would still be much flatter than the DMT .001" claimed flatness.

Chris L

Originally Posted by Chris L

Ok guys, here's an update:

Harrelson Stanley called me after receiving my GDLP today.

He's going to soak it and lap some ceramic stones on it this weekend to check its performance. According to him, the initial observation is that the stone looks as it should after being broken in as it has.

He's also going to most likely take a ceramic disc to it to lap the GDLP. I told him I was concerned that this would alter the flatness. He explained and stressed that the Shapton .5 micron flatness claim is the flatness of the FLOAT GLASS substrate and not the lapping surface given the fact that each diamond will be slightly different than the other.

I've always used very light pressure with my lapping plates, DMT or Shapton letting/expecting the diamonds do the work. Harrelson said that when he laps on the GDLP he (direct quote here) "puts his shoulders into it". He says that using the GDLP, he can true even severely used ceramic on glass stones in less than 30 seconds. He is going to mail my photos to Shapton in Japan for viewing. Harrelson says his understanding of the GDLP manufacturing process is that the edges of the stone do have a higher concentration of diamonds than the middle or "field" (his reference) of the GDLP has.

Harrelson said he has a beverage cooler that he keeps filled with water, and usually has about 10 GDLPs soaking and submerged continually in that water with no ill effects to the GDLP. He does this to prevent slurry from hardening on the GDLP surface.

He also said that hot water will not harm the GDLP. He said he's actually contemplated putting his GDLP in the dishwasher but has not done it yet, and he stressed that he doesn't think that Shapton would endorse such a practice, but given that the hot water in a dishwasher wouldn't melt glass, diamonds, nickel or rubber, it most likely would not harm the GDLP.

That's the current update for now.

Chris L

This is encouraging. Thanks for the update. I also use a light touch when lapping my Shapton pros and can flatten one that I have been using and just needs a touch up in very short order. Maybe thirty seconds. A new one in a minute or two depending on the stone. I hold the GDLP in one hand and the stone in the other under the running water in the kitchen sink. I use a fingernail brush to scrub the plate after lapping it to remove any stubbron slurry. I hadn't thought about soaking.

Originally Posted by JimmyH-AD

This is encouraging. Thanks for the update. I also use a light touch when lapping my Shapton pros and can flatten one that I have been using and just needs a touch up in very short order. Maybe thirty seconds. A new one in a minute or two depending on the stone. I hold the GDLP in one hand and the stone in the other under the running water in the kitchen sink. I use a fingernail brush to scrub the plate after lapping it to remove any stubbron slurry. I hadn't thought about soaking.

Jimmy:

My process for lapping using the GDLP has been EXACTLY the same as yours down to even the fingernail brush. I don't know that I see a need for keeping mine (if when I get it back!) submerged in water since mine isn't seeing heavy use.

Chris L

Chris, you mentioned DMT sending you a cleaning kit for your plate. What does that consist of and is it any good?

Originally Posted by JimmyH-AD

Chris, you mentioned DMT sending you a cleaning kit for your plate. What does that consist of and is it any good?

I sold the new replacement DMT D8E and the courtesy cleaning kit to a fellow member some time ago. I guess the cleaning kits can be purchased through DMT directly (you have to ask for them and I think the cost was suggested at $20). It was really neat. It came in a blue nylon canvas zipper pouch and had a bottle of the cleaning powder and a small brass bristle brush.

I used a bit of the powder and the brush on a D8C and I was very impressed. It was as though it refreshed the D8C! IIRC, the ingredients mentioned silica flour and some surfactants. I've tried Bon Ami powder on a small DMT that I have and that works well, but that DMT cleaning powder really impressed me. $20 impressed me?........ I'm not the cheapest guy on the block, but if it were $10, I probably wouldn't hesitate to buy it. I can't remember who I sold the DMT stones to so I don't know how the DMT powder is fairing for him.

Chris L

Thanks Chris, I'm with you, the Bon Ami will do

Originally Posted by Chris L

Yep, the float glass has that guaranteed flatness. Harrelson said even if the GDLP surface is lapped/refreshed, with .5 flat for the glass, the actual but undetermined flatness of the GDLP surface would still be much flatter than the DMT .001" claimed flatness.

Chris L

I'm sorry, I just can't stand for this kind of nonsense. (No not yours Chris, Harrelsons!). How the h*ll can he claim that an "undetermined" as in unmeasured or verified surface flatness of a hand lapped hone will be much flatter than that of another hone which is guaranteed by the manufacturer not to *exceed* a .001 deviance in flatness?!?!?! First off, as Harrelson has up front admitted that the .5 is nothing more than the accuracy of the substrate which has (according to his own statement) absolutely nothing to do with the surface of multiple layers of diamonds or rather a slurry of diamonds in some sort of binder and who afterwards makes no claims to have measured or made any guarantee of the accuracy of it's surface after manufacturing or for that matter after hand lapping yet there he is saying he knows (nudge nudge.... wink wink) it has to be way more accurate. After all, he's charging you nearly 6 times the cost of a DMT so it has to be better, right?!?!

Nope, I don't buy into his statements, or the "substrate" is flatter, therefore the surface must be as well. If they are laying down multiple layers of diamonds on top of this substrate, they would have to re-surface the hone in order to know what level of flatness it has. It's like pouring concrete, the substrate can be made very flat but unless you tightly control the pouring and leveling of the final top coat, the substrate accuracy is lost.

Now, lapping by hand has been done for many, many years and it is well known that it can be done quite accurately but it does require skill and must be verified by some method of measurement if you want to make some form of claim about it. Lapping or surface scraping is often measured by using a layout dye and a surface plate of known accuracy. Strangely enough, those folks skilled in lapping and or scraping surfaces to make them dead flat have to frequently check them on the surface plate to gauge their progress and help decide when they have reached a given measure of accuracy. It does not appear that Harrelson is taking any of these steps and therefore his claims are meaningless to me.

Now, if you take Harrelsons description of how he uses the DGLP to flatten hones, it becomes quite apparent that he's shooting for "good enough" and not absolute flatness and of course he is correct. This is not nano technology, a thou here or a thou there is not going to make one damn bit of difference and so sloppy, heavy handed lapping is acceptable... h*ll, it's even encouraged as after all, the more you lean on the flattening hone, the faster you'll be back to buy another hone!

Shapton Glass hones are a great product, I'm super happy with mine but Shapton can keep their over priced diamond lapping plates. The best lapping system they have is really the cast iron plate/powdered abrasive system. It's tried and true, been used for decades and is known to remain accurate to any reasonable degree if used correctly.

Regards

Kaptain "I stands all I can stands but I can't stands no more." Zero

Originally Posted by kaptain_zero

I'm sorry, I just can't stand for this kind of nonsense. (No not yours Chris, Harrelsons!). How the h*ll can he claim that an "undetermined" as in unmeasured or verified surface flatness of a hand lapped hone will be much flatter than that of another hone which is guaranteed by the manufacturer not to *exceed* a .001 deviance in flatness?!?!?! First off, as Harrelson has up front admitted that the .5 is nothing more than the accuracy of the substrate which has (according to his own statement) absolutely nothing to do with the surface of multiple layers of diamonds or rather a slurry of diamonds in some sort of binder and who afterwards makes no claims to have measured or made any guarantee of the accuracy of it's surface after manufacturing or for that matter after hand lapping yet there he is saying he knows (nudge nudge.... wink wink) it has to be way more accurate. After all, he's charging you nearly 6 times the cost of a DMT so it has to be better, right?!?!

Nope, I don't buy into his statements, or the "substrate" is flatter, therefore the surface must be as well. If they are laying down multiple layers of diamonds on top of this substrate, they would have to re-surface the hone in order to know what level of flatness it has. It's like pouring concrete, the substrate can be made very flat but unless you tightly control the pouring and leveling of the final top coat, the substrate accuracy is lost.

Now, lapping by hand has been done for many, many years and it is well known that it can be done quite accurately but it does require skill and must be verified by some method of measurement if you want to make some form of claim about it. Lapping or surface scraping is often measured by using a layout dye and a surface plate of known accuracy. Strangely enough, those folks skilled in lapping and or scraping surfaces to make them dead flat have to frequently check them on the surface plate to gauge their progress and help decide when they have reached a given measure of accuracy. It does not appear that Harrelson is taking any of these steps and therefore his claims are meaningless to me.

Now, if you take Harrelsons description of how he uses the DGLP to flatten hones, it becomes quite apparent that he's shooting for "good enough" and not absolute flatness and of course he is correct. This is not nano technology, a thou here or a thou there is not going to make one damn bit of difference and so sloppy, heavy handed lapping is acceptable... h*ll, it's even encouraged as after all, the more you lean on the flattening hone, the faster you'll be back to buy another hone!

Shapton Glass hones are a great product, I'm super happy with mine but Shapton can keep their over priced diamond lapping plates. The best lapping system they have is really the cast iron plate/powdered abrasive system. It's tried and true, been used for decades and is known to remain accurate to any reasonable degree if used correctly.

Regards

Kaptain "I stands all I can stands but I can't stands no more." Zero

remember hms is not the manufacturer. the compact lapping plate will not remain flat at all. The amount of pressure is less important than how and where the pressure is applied imho. However your point about returning for a new stone gave me a chuckle. He is a salesman afterall

I noticed King has some diamond hones recently, pretty expensive but their sintering(sp) process sounds very interesting.

Originally Posted by kevint

remember hms is not the manufacturer. the compact lapping plate will not remain flat at all. The amount of pressure is less important than how and where the pressure is applied imho. However your point about returning for a new stone gave me a chuckle. He is a salesman afterall

I noticed King has some diamond hones recently, pretty expensive but their sintering(sp) process sounds very interesting.

You are of course correct, hms is NOT the manufacturer but he IS the one making the statements!

The comment about the pressure relates to ones ability to control the honing accuracy, leaning on it just reduces the chances of honing evenly, just like using a dull knife with extra force is more likely to result in something not so desirable happening.

Cast iron laps if used properly *will* remain usefully flat for years, used incorrectly.... well..... there you go.

I wasn't aware of King getting into the diamond hone arena... I'll have to look into it and I've heard of another Japanese diamond hone/lap called something like Atomic or?!?!?! Apparently it's prone to rusting but works well for lapping Japanese natural hones......

Regards

Kaptain "I calls'em as I sees'em" Zero

When I was looking at buying the GDLP I talked with Harrelson about the differences between the cast iron and the glass plates. I was concerned that if I were to drop the glass it would break, He said that if you drop the iron it could go out of whack. The stone lapping side on the cast is diamond just like the glass. Here is the cast plate described on the web. I think the powder is for the iron side to true chisels. He says never to use it on the diamond side.