I’ve been working on cleaning some diamond plates up so I could get better images under the microscope. The quest came about in answer to a question in another thread about whether the diamonds themselves can become worn down. So, I started experimenting with some different chemicals that I had around the office. I tried:
White Vinegar
Simple Green
Barkeeper's Friend
Rubbing Alcohol
Ferric Acid (PCB Etchant)
I used the ferric acid full strength, just to try it out. From what I've read, when it's diluted, it shouldn't harm the nickel plating while still dissolving the steel. The video below shows what happens when you use it full strength. The video is taken under the microscope at 632x and is sped up to 300%:
Nothing has really stood out yet but I don’t think I did enough testing yet. In theory, the vinegar should work really well to dissolve the iron, which it would turn to iron acetate. I’ll keep testing stuff and eventually put together a report. Everything did fine as far as making the plates look good to the eye and feel rougher again. It’s more at the microscope level between the stones that I’m working on.
Outstanding Clay , great idea!, As you all know, I not only love the science of it all but also the not knowing the outcome part. It’s like opening a present as you see the results revealed.
I spent a little more time on this today, just testing white vinegar with excellent results. I let a dropperful of vinegar sit on a worn 100# plate for 15 minutes and could easily see the solution bubbling away as the acetic acid dissolved the steel and created iron acetate and hydrogen. I then scrubbed the surface of the platen for a few minutes with a wire brush, first with vinegar, then with soapy water until the suds were gone and then gave it a good rinse. Nearly all the metal filings between the stones were gone. One thing I found though is that when the plates are loaded, it’s not just the spaces in between the stones that are covered in metal but the stones themselves. Once I cleaned them well, the stones were much clearer and I could see little pockets where some metal was still left, like looking at a tooth with a filling:
[attachment file=“Worn-100#-with-Metal-Flakes.jpg”]
The above image is of a single 100# diamond, taken at 800x as a series of images and then stacked for extended depth of field. The shiny spots are bits of metal embedded in the nooks and crannies of the stone.
I’m wondering if cleaning them so thoroughly will offer any improvement in stock removal or finishing of an edge, or if it’s so minute it doesn’t matter?
Ive got the perfect test subject to try that out myself, hopefully by next week if the scope gets here(getting excited!).
My original 100 grit paddle is so worn that heavy pressure is needed just to do anything. I thought it was worn out, but now am wondering if its just clogged flush…interesting.
Does this mean that white vinegar is Wicked Edge approved?
Not quite yet… I need to do more testing to see if the concentration of acetic acid in the vinegar is low enough to not damage the nickel. I’ll get a stone immersed today and let it stay overnight and then have a look on Friday.
Do you have an idea as to how the metal filings are attached to the diamonds - why they don’t just wash off? I could understand where filings of a range of sizes might find pockets in which to lodge themselves, but those small flakes which seem to be attached to the surface of the diamonds? Or are they just loose trash?
I think they’re so small that they are just kind of pasted into the little irregularities on the surface of the stone. Most of the bits of metal are under a micron in width with the biggest one measuring 2.5µ. They’re so thin that they probably flow like plastic when they’re pressed into the stones and stick in pretty well.
Great pic, Clay! Since a while I use Bartenders Friend to clean my stones. I had to import it from the UK, but it works noteably better than local cleaning powders, since it contains an acid (oxalic acid). It seems you’ve found an much cheaper ingredient that’s locally available everywhere .
Oxalic acid is about four orders of magnitude more acidic than the acetic acid in vinegar, so if you’ve had no issues using barkeeper’s friend, then vinegar should also be safe for the platens.
I’ve been studying the effects of vinegar and haven’t seen any loss of diamonds so far, though I need to do a little sharpening after the cleaning to be absolutely sure the bond holding the diamonds in place is still strong.
As a new owner of a WEPS I find this forum interesting, yet (sometimes) confusing. For example, there seems to be several options for cleaning my diamond plates, however, I am finding it difficult to identified the recommended method by the manufacturer.
If possible can someone point me to the how to or perhaps summarise (think beginner here) the process?
Good point. However, I don’t know how much oxalic acid Barkeeper’s Friend contains. I googled it, but couldn’t find it. According to Wikipedia, vinegar contains 5-20% acetic acid.
On a related note, most aggressive cleaning products use (unlike Barkeeper’s Friend) bleach as their active ingredient. Does anyone of other cleaning products that use an acid as their active ingredient? I’ve got some particularly aggressive BBQ cleaner by Weber in the house, but I don’t know the ingredients.
I cannot speak for the manufacturer, of course, but I think the most common method for a thorough cleaning uses a toothbrush and some soapy water. I also tried putting my stones in the dishwasher. That worked well, but is definitely not recommended by the manufacturer .
I have had good luck with the liquid version of Barkeeper’s Friend and an old stiff toothbrush.
I usually wet my stones during use, so I go 20-30 sharpening sessions between cleanings.
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