Wondered if there was anything that can be done to prevent a coticule from cracking. I have one that the bottom it in tact but the coticule is showing signs of cracking. Is there any remedy to keep it from breaking?
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Wondered if there was anything that can be done to prevent a coticule from cracking. I have one that the bottom it in tact but the coticule is showing signs of cracking. Is there any remedy to keep it from breaking?
Are you sure it's a crack? Sometimes coticules have little veins that look like cracks but aren't. Also, was it always this way and you just want to make sure it isn't getting worse? Or is it getting worse before your eyes?
Many coticules have little veins that WOULD be cracks and exactly why they bond them to slate! If well bonded though it should be fine.
Tony
I have heard you can paint the sides of natural stones to prevent cracking and have seen one or two painted stones, so I imagine there is some fact in that theory. I'd just make sure the coticule is thoroughly dry before applying the paint, in case it locks some moisture in then stuffs it completely.
I think only Japanese stones get painted, if at all - because they have a specific structure (different from coticule)
If you cannot feel the crack with your nail - it's considered OK to use.
Probably most relevant for you: some scratches in the coticule that may appear as cracks disappear with a good lapping
Best of luck
Ivo
It does happen and folks have told me about it the phenomena in vintage as well as stones more newly mined. Unless the crack is really interfering with the honing, don't worry about it. What I mean by really interfering is that the razor catches on the crack every time you hone. If it's just a concern instead of a real problem, don't worry about it but keep an eye on it. I have lots of natural stones of all types and many look like they're cracking but on closer examination the "cracks" are veins or discoloration or tiny cracks in the stone that don't interfere with honing and don't seem to grow.
The Japanese honyamas have cracks, veins, chips, and all manner of what we consider to be problems. The Japanese talk about the stone's character and learning to work with the stone's nature.
The thing to remember is that these are natural products. They grew in place as opposed to being manufactured by people. They're each and every one different.
The crack is real and luckily it is located near what is usually the bottom left corner of the hone so it does not really present a problem. Next to it is a much larger vein that turned into a 4mm chuck that popped out a while back. This is a vintage stone that is soft feeling and is glued securely. The newer crack is more noticeable after watering the surface for honing. When dry it is not very prominent. Thanks for the info. I figured I would just have to hone around it - at least until I get a new one from Howard sometime :)
Cracks in rocks happen two ways. There are external cracks which come from weathing processes and internal flaws which progress on their own. We don't have to worry about external problems since the coticule is safe and sound in our houses but the internal flaws can still grow. It doesn't take much. Slight impact, vibration. painting a crack will do nothing for these types of flaws because they don't start at the surface. They have materials used to stabilize flaws in rocks in places like dam sites but I don't know about coticules.
Whilst I am still trying to find info about painting a natural hone, from what I understand (with Japanese hones anyway) it is ideal to paint the sides of a hone because they absorb water fast like a tissue, which causes cracks to worsen. Any internal flaws can be retarded by painting the sides preventing excess amounts of water being absorbed.Quote:
Originally Posted by thebigspendur
This could just be for Japanese hones as Izlat said.
I just thought it was worth mentioning.
Most Japanese finishing type hones are clay or alumina based. The problem is its not the moisture per se that causes the cracks to enlarge but what happens to the water once it enters the rock and the crack. if the water enters and slowly dries I don't see how that will enlarge a crack. In nature its the entry of water and temperature extremes that cause the crack to expand or pressure differences on the rock. These things don't happen once its inside your house. Maybe if the stone is treated very roughly an internal flaw will grow but I don't see the painting affecting these type of cracks. if its an external crack started by weathering then maybe it will help.
Are you saying even if the crack does NOT pass the fingernail test, it may still be fine as long as the blade itself isn't catching?Quote:
Originally Posted by Howard
I just received a beautiful pink coticule (6x2 natural combo) with a 2" long crack at one end. The crack is severe enough to easily catch on my fingernail. I was thinking of either cutting the stone to a nice crackless 4x2 size or filling the crack with Hot Stuff CA. (I was leaning toward option 2.) However, I used the stone last night without a problem--DMT 1200, BBW side with slurry, coticule side with water, leather strop. The result was a smooth shave.
So I guess my main question is...do I even need to bother filling the crack? (The razor doesn't catch during honing at all, at least not that I can feel with my newbie hands.) And are there any cons to filling a coticule crack?
Thanx,
Christopher
Ive never had to deal with this issue, but sooner or later I would believe the crack is going to get you. I would fill it and once cured, lap it.
I have definately heard about painting Japanese stones (I think it was shellac or something that was to be used), and the reason I heard was that they absorb water, just like OS said. However, coticules (and BBW's) do not absorb water, so there should be no need to seal them.Quote:
Originally Posted by OLD_SCHOOL
I can't recall the thread but I think I saw a post where Ardennes will fill cracks in BBWs and maybe coticules with a substance that is softer then the material in the stone. Bart will probably know or you could PM Rob at Ardennes and get his advice.
In the old days, small cracks were filled with a sort of glue, based on beeswax. They used the same glue for attaching the Coticule to its backing part. This required heating the stones in a pan, or an oven, but I wouldn't recommend that today. I have not enough data on temperatures, there's the risk that your hone will crack further, and the risk on a vintage Coticule that it will separate from its back.
Ardennes Coticules uses some kind of industrial high performance tiling glue for natural paving stones. And I think they also use it as a filler. For domestic use, I have successfully reglued a piece that cracked and separated from the back of a slurry stone, with CA glue. It can also be used to fill small cracks. Just drip it on the crack and let gravity do the work. When it no longer soaks into the hone, give it a short lapping session for a flush result. I have also tried dripping candle wax (in the right color), but it didn't work well without heating the Coticule to a point only slightly below the melting temperature of the wax. As said something I wouldn't advice if you're not prepared to accept more trouble.
Bart.
Thanx, everyone. I'll pick up some Hot Stuff CA next weekend. Hopefully that'll do the trick.
Me =)