New silicon carbide based Washboard compound

HeavyHanded

HeavyHanded

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Jun 4, 2010
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Have finalized a silicon carbide based compound for use with higher carbide content steels and some of the high RC carbon. The original AlumOx compound can do a great job of finishing those steels off and recovering light usage, but struggles somewhat when trying to fully recondition the more wear resistant stuff - the SiC has no such problem and does an admirable job on the mainstream steels (the knife in the accompanying video is carbon steel in the 58RC range). The AlumOx is still a slightly better choice IMHO for common stainless and carbon, so will be offering an option between the two, or both for a modest additional cost.

There are some small differences in the best-practices of the SIC compound relative to the AlumOx, so made a short video for explanation - also included paper towel cutting demo as a nod to some of the recent discussions on the forum.

Will work out a deal for current owners that want to receive the SiC formula.


Thanks for watching...
Martin


[video=youtube;Ls0WJp08iVY]http://www.youtube.com/watch?v=Ls0WJp08iVY&feature=youtu.be[/video]
 
So what are the Min , Max and Mean Particle sizes in this formulation?
I've been interested in a silicon carbide stropping compound for awhile now. Its high friability should mean that the more you work it the finer it should break down.

You consider this to be in the 4k range?
 
Sadden said:
So what are the Min , Max and Mean Particle sizes in this formulation?
I've been interested in a silicon carbide stropping compound for awhile now. Its high friability should mean that the more you work it the finer it should break down.

You consider this to be in the 4k range?
Click to expand...

I am sorry I cannot divulge the specifics, that formula is proprietary - took me many, many batches to arrive at a good product. I can help you out with a few observations though -

The grit I buy comes from a lapidary shop and is graded pretty well. If you take a pinch from a sample and look at it under magnification you'll see high uniformity. If you wipe a finger along the inside of the bag and look at this sample, you'll see quite a few "fines". It does break down some with handling, and a bit more when mixing in my double boiler but not to any huge degree as an overall percentage.

SiC can be fractured down with relative ease between two surfaces, but they both have to be very hard. In use on a strop, even as hard as the Washboard, I do not believe it breaks down much further. Any additional breakdown under that sort of use might be undesirable anyway, as it would most likely be working the particles to less aggressive shape - knocking off the sharp points instead of breaking it enough to reveal new, sharp points. It should polish more but sharpen less and would be impossible to control or predict. From what I have observed under microscope the particles don't appear to break down on the paper strop, at least not with a handful of uses before that sheet gets retired, and that's a good thing IMHO.

In my experience, the toughest part is getting the SiC to work as well on carbon and common stainless as it works on the tougher stuff. The shape of the grit is not as aggressive to start with, so unless its firmly fixed in place it tends to polish, rather than bite in like AlumOx or diamond of a similar grit size. Loose SiC functions almost the inverse of fixed SiC - fixed it is a relentless grinder - loose it trends toward polishing. Finding the right mix of abrasive and binder, and type of binder that will work best for your application can cause one to loose their mind. The same grit will perform very differently depending on the variables.

The good news is that its relatively cheap and common, and fairly benign, so inexpensive and safe to experiment with. It also seems to blend well with and release from a lot of different binder materials, so somewhat forgiving in that respect.

I consider it to be in the 4k range, but following the second step as done in the video, might be closer to 6k.

Thanks for watching!
Martin
 
HeavyHanded said:
(...)
In my experience, the toughest part is getting the SiC to work as well on carbon and common stainless as it works on the tougher stuff. The shape of the grit is not as aggressive to start with, so unless its firmly fixed in place it tends to polish, rather than bite in like AlumOx or diamond of a similar grit size. Loose SiC functions almost the inverse of fixed SiC - fixed it is a relentless grinder - loose it trends toward polishing. Finding the right mix of abrasive and binder, and type of binder that will work best for your application can cause one to loose their mind. The same grit will perform very differently depending on the variables.

(...)
Martin
Click to expand...

That's what I've noticed with the SiC compound (powder) I've used for stropping. Because it tends to polish very fast on simpler steels like 1095 and 420HC/440A, etc., I tend to minimize how much I strop these steels with it. Very handy in a few passes, for scrubbing away fairly heavy burrs and wires; but once those are removed, I'll immediately go to green compound on those steels. A steel like D2, however, is much more forgiving with extended SiC stropping, and even will benefit from it, I believe. Seems to work well for shaping the big carbides known to be in D2. Also does fairly well with 440C, I think for essentially the same reason.


David
 
There went a lot of thoughts in your compounds - very impressive Martin and thanks for sharing and offering this for sale!!
For the steels that I use the most (O1, 1095, 5160 and 52100), AluOx compound is the way to go then in your opinion?
 
awestib said:
There went a lot of thoughts in your compounds - very impressive Martin and thanks for sharing and offering this for sale!!
For the steels that I use the most (O1, 1095, 5160 and 52100), AluOx compound is the way to go then in your opinion?
Click to expand...

Definitely. It just handles a little easier and on those steels will leave a nicer finish (will certainly cut a paper towel in similar fashion). More tolerant of pressure, loading etc. It took a lot of tuning and much anguish before the SiC compound would perform well enough on your listed steels for me to offer it. If it could only do a good job on the "super" steels I probably wouldn't bother - might only confuse people. At this point if you were looking to buy the kit and had no preference or idea what steels you might wind up using most often, I'd recommend the SiC simply because it will handle a wider range of steels and do so very well. For fine grained stainless and carbon, the AlumOx is a better choice, but I've shrunk the margin quite a bit with this formula.

Martin
 
This Christmas, I'm giving away packages of s30v, s35vn, and D2 with accompanying WashBoards to certain select family members, so I'd certainly like to get my name in the hat for four of these SiC compounds (one for each of us-not being greedy). If that's feasible. If not, then one for me, so I can be special.:D However that works out, my hat's off to you, Martin. Inquiring minds are everywhere; those who expend and risk to bring ideas to useful fruition are deserving of high accolades. On behalf of the strop-challenged everywhere, I applaud your results.:cool:
 
StevieWunders said:
This Christmas, I'm giving away packages of s30v, s35vn, and D2 with accompanying WashBoards to certain select family members, so I'd certainly like to get my name in the hat for four of these SiC compounds (one for each of us-not being greedy). If that's feasible. If not, then one for me, so I can be special.:D However that works out, my hat's off to you, Martin. Inquiring minds are everywhere; those who expend and risk to bring ideas to useful fruition are deserving of high accolades. On behalf of the strop-challenged everywhere, I applaud your results.:cool:
Click to expand...

Steve, send me an Email or PM when you get a chance.
Martin
 
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