applying urushi on natural stones

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Asteger

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I've got several Japanese naturals and I've ordered some urushi to coat the sides and maybe the bottom on some of my stones. I'm wondering about other people's experiences with this?

Some of my stones have no lacquer, etc, on them now, so no problem and I should be able to just go ahead and apply the urushi. However, others already have a kind of shellac. If I decide to apply urushi on these too, I'm not sure if I should first attempt to sand off some of the shellac or not. If not then the urushi might not adhere as well?

Naturally, I'd like to avoid trying to remove any shellac if possible - more work and there's also the possibility of damaging the stones; I suppose sanding would be the only option. On the other hand, I don't want to experiment too much and waste the urushi.

The other thing I thought someone might have an opinion on is whether to coat the bottom of the stones as well. Often this seems to be done, but I've also read that traditionally urushi might just be applied to the sides of naturals. Extra protection if the bottom is coated, of course, but if the bottom is pretty strong and stable it might not be needed and I was thinking that not having urushi down there might allow the stone to breathe better and dry out well.

Thanks for any thoughts on this.
 
Sorry for the off-topic response, but can you share where you get urushi?
 
I really wish John would just start stocking this stuff it should be relatively easy for him....hint hint
 
I found out that in US is actually forbidden to sell real Urushi as it is very toxic :( I read it on some sword forums. Maybe i am wrong ??
But some do sell cashew, still it have to be shipped special with grownd shipping.

I apply my Urushi just with a brush. One layer thats it dry for 24 hrs
 
Maxim - what do you think of my question above, if it is good to apply urushi to a stone that already has shellac or lacquer on it. And if so, should some of that be sanded off first?
 
I dont know. Never try it on shellac :dontknow:
 
I found out that in US is actually forbidden to sell real Urushi as it is very toxic :( I read it on some sword forums. Maybe i am wrong ??
But some do sell cashew, still it have to be shipped special with grownd shipping.

I apply my Urushi just with a brush. One layer thats it dry for 24 hrs


I seen the same info but I'm not sure if I believe it? I can't find anything outside of various types of forum chatter that says it's the case. There are other Artist supplies readily available in the states that are far more Toxic that come to mind. www.hyper-cafe.com I think went out of business?? I haven't Ben blue to get there websight to open for about a year or so, maybe it's my browser?

As for the question about going over old lacquer.
I don't know why you would want to do this? Is the old lacquer chipped, or are you just wanting to redo it in a more traditional way?
either way my suggestion if you're going to go over the old finish is to remove it if possible with it appropriate solvent I.E. Denatured alcohol for Shellac. If the finish is one that can't/won't some what easily "wash off" like shellac will(epoxy comes to mind) then just "scratch up" the old finish with sand paper, no need to remove it by sanding it off it it already attached to the stone well.
 
That will be nice to find out what is regulations is for those stuff. I got shipped Urushi to me from Japan with no problem. And yeah i think also there is many more toxic stuff out there then Urushi that been sold :D
 
I found out that in US is actually forbidden to sell real Urushi as it is very toxic :( I read it on some sword forums. Maybe i am wrong ??

That's too bad if you have a lot of US customers, as I said you might consider selling some yourself. However, maybe you still can? Just display a note with the urushi that this product cannot be shipped to the US.
 
That's too bad if you have a lot of US customers, as I said you might consider selling some yourself. However, maybe you still can? Just display a note with the urushi that this product cannot be shipped to the US.
Hyper Cafe has urushi, but I'd go with Cashew lacquer. Urushi is known to cause severe allergic reactions after a few uses, while cashew does not and works just as well. All my Jnats are cashew lacquered, and from what I have seen in Japan this is widely used. Urushi needs certain temperature and humidity conditions to dry correctly (and it takes a few days), or at least that is what the instructions I have seen stated.
 
As for the question about going over old lacquer. I don't know why you would want to do this? Is the old lacquer chipped, or are you just wanting to redo it in a more traditional way?

Thanks for your suggestions, Chef N - yeah, I was thinking I'd have to take sandpaper to it as well as perhaps try and dissolve it a bit somehow. Why? I just like the look of urushi or some kind of solid lacquer on stones. It also appears to offer more support to the stones over the years (can have a thicker, softer appearance). I've also got a couple of stones I've bought that, while very good (and pricey), haven't been finished well with lacquer (swarf stains on the sides) and so I figure they'd look a lot better to me after some treatment. And overall, I just think it'd be cool to try.

Thanks Mainaman - I haven't been too worried about allergic reactions, but I'll also consider the cashew. From what I can tell it looks the same when finished, while the urushi smells nicer ... or at least not like lacquer.
 
Thanks Mainaman - I haven't been too worried about allergic reactions, but I'll also consider the cashew. From what I can tell it looks the same when finished, while the urushi smells nicer ... or at least not like lacquer.
They are SEVERE allergic reactions, like Poison Ivy type of allergic reactions, consider that for a moment. Cashew is the best in my book, the cans you get from hyper cafe, are enough for many stones, if you thin the content.
 
SEVERE allergic reactions? Hehe, don't mean to be facetious but it's almost sounding cooler in my book. "Hey, don't touch my stones! Want a deadly rash?"

But really I wonder why urushi would have been used for generations if it is so toxic. Seems it is generally so mostly when it hasn't dried. Guess I'll find out.

(Incidentally, I'm immune to poison ivy and apparently there is a connection.)

In the mean time, yes, I'll be looking into cashew too.
 
I read that cashew can be as poisons as urushi :p Thats why it is on restriction list too
 
I read that cashew can be as poisons as urushi :p Thats why it is on restriction list too
That's because Cashew shell contains Urushiol as well, but in less quantities then "Chinese lacquer tree" and it can be air cured so it's supposed to be safer....
 
SEVERE allergic reactions? Hehe, don't mean to be facetious but it's almost sounding cooler in my book. "Hey, don't touch my stones! Want a deadly rash?"

But really I wonder why urushi would have been used for generations if it is so toxic. Seems it is generally so mostly when it hasn't dried. Guess I'll find out.

(Incidentally, I'm immune to poison ivy and apparently there is a connection.)

In the mean time, yes, I'll be looking into cashew too.
It is only bad when you apply, after it is dry it is no longer causing problems.
My guess as to why it was used for generations is that it was the only thing available that was good enough to do the job. Cashew is fairly new stuff that is chemically derived from urushi (I believe) that has no adverse effects.
 
I read that cashew can be as poisons as urushi :p Thats why it is on restriction list too
Max,
I think it is restricted because it has flammable solvents in it, other than that it is harmless, I have had it on my hands many times while sealing stones.
 
Hyper Cafe has urushi,.

Can you still find there web sight? I think they went out of Business?

I read that cashew can be as poisons as urushi :p Thats why it is on restriction list too
How about "flake white" paint, that's still easy to get and lead based paint are pretty toxic

two stage urethane paints will give you bigger problems then poison ivy

There are more "art Supplies" then you can think of that can kill you, don't drink turpentine!

As to why urushi was/is still being used. Remember it's primary use is not to protect polishing stones it's used in a highly Specialized art form. An important component of the Japanese art of lacquerwork is the special technique known as "urushi", which uses many layers of wafer-thin, semi-transparent lacquer to create a surface of almost mystical radiance and depth. Many different things have been invented/ used to try and recreate the look and effect of Japanese lacquer work, including cashew, japanning, and even modern day urethane "candy coat" pants, when they paint a car that say they are " spraying lacquer" but in all Actuality it's urethane.
 
yup shows up on my comp. Did you get banned from them or something???:razz:
 
Thanks for the discussion so far. Let me post the question below again:

The other thing ... is whether to coat the bottom of the stones as well. Often this seems to be done, but I've also read that traditionally urushi might just be applied to the sides of naturals. Extra protection if the bottom is coated, of course, but if the bottom is pretty strong and stable it might not be needed and I was thinking that not having urushi down there might allow the stone to breathe better and dry out well.

Does anyone just coat the sides (with lacquer or whatever you use) our does everyone like to do the bottom as well?
 
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