Shou Sugi Ban - Does anyone have any advice based on experience?
Hello All,
For the past couple of months I've been experimenting with Shou Sugi Ban... refer youtube or other threads if you're not sure what it is.
I am looking for some practical advice, hopefully from anyone who may have experimented with the technique and used it in a real world application... preferably externally and preferably for cladding as per the traditional use.
This post (or more specifically the comments below it) has been the most helpful thing I've found but I'm still no closer to where I need to be.... there are so many knowledgeable people on here I'm hoping someone might be able to help.
My main issue is ongoing char rub off which I have been unable to solve.... Like most people who are trying it now I'm using a propane torch (weed burner) and then a wire brush to remove loose char before washing.
Irrespective of which species I use (I have tried a variety so far - some soft, some hard) or how hot/close the torch is, char continues to rub off when the wood is touched... the only way to avoid this is to wire brush and wash so heavily that I remove almost all of the char which defeat the purpose of the process (also this only works with softwood, not hardwood).
I'm reasonably sure the issue is with my finishing process and my understanding is traditionally the wood is oiled with Pure Tung oil... I've tried that (upto 3 coats with 48 hours drying time between each) and it makes no difference... the char continues to rub off. Internal clear coats (estapol etc) lock the char in but they obviously aren't suitable for external use.
I'm interested in the process because I love the look and everything I've read says once the process is done (correctly) you can leave the timber exposed for years without any maintenance.... hence I want to avoid any kind of surface sealing product that needs to be re-applied regularly. I'm also pretty sure the wire brushing is not even required as many people apply a heavy burn to softwood to create an alligatoring/leather effect which they leave exposed... that surface leaves your hands black at the slightest touch and is reasonably fragile so I assume they're relying on the oil to keep it looking the way they want.
All of the articles and videos I've found show the burning process in detail at the beginning of a project but no one talks about the oiling and controlling the char rub/wash off and no one ever posts follow ups in the future where they discuss how the timber is performing in the months and years after the first burn.
So, does anyone have any advice that might help?
- Am I putting the oil on too quickly? IE Do I need to just first leave the timber exposed to the elements so the char will be blown/washed off by the weather?
- Is there a different oil I should be using? Overseas they use a product called Penofin (which I can't find here) and (ironically) a product called Cabots Australian Timber Oil, which is a linseed/tung blend that of course is not sold here.
- Am I just expecting too much from the process? Is char rub/run off just the daily reality of the Shou Sugi Ban process and no one talks about it?
- Is there something that I need to do AFTER the oiling? In one of the most prominent youtube videos they re-torch the wood AFTER it's oiled... just a lick and they mention something about sealing the oil in... I haven't tried this (but will shortly).
Any advice would be most appreciated and of course I'm more than happy to share what I've learned with anyone who's interested (although I don't claim to be any kind of expert and I have very little experience with wood finishing in general).
Thanks,
TC
Now doubting it works anyway
What started me thinking about this again is that I went for a walk through a forest burned about 2-3 years ago. I couldn't help noticing that the fire-scorched timber had rotted down just as quickly as the unburnt timber, in fact I think more quickly. That's kind of inevitable really, if there was something magical about scorched timber not rotting then - with a countryside that burns as often as Australia's - we'd all be up to our noses in fire residue.
So I'm wondering if there is really any proof that Shou Sugi Ban really does provide weather-resistance. What makes us think it does ?
Some other thoughts:
Most of the modern practitioners and service providers seem to oil their product, which indicates to me they have no confidence in it working.
The Japanese seem to have plenty of timbers with remarkable natural weather-resistance. Maybe the scorching actually doesn't contribute much at all and doesn't need to.
There are so many myths about Japan here in the West it pays to have a reasonable level of scepticism.
I know charcoal has weather-resistance, but charcoal is made by burning timber in the absence of oxygen. Burning timber with a blowtorch isn't making charcoal - its just making burnt timber.
Not sure about this. Just thinking out loud.
Any thoughts.
Arron