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scottbr
29th July 2023, 11:18 AM
For the bench in my last ever DIY bathroom reno.

It's all blackwood. Lovely timber.

I've finished it in Osmo Hardwax Oil, which is a favourite of mine.

Three coats.

The vertical pieces are fine, but the water is marking the bench.

Have I chosen the wrong finish, or do I need more coats?

(This is the only forum I frequent where my photos end up on their side - apologies.)


Scott529204529205

droog
29th July 2023, 11:39 AM
Never used the product myself but there was a lot of discussion on the (now closed) RenovateForum.

There were a number of members that had the exact same issue of water stains with the Osmo finish, even after contacting the manufacturer there was no resolution for the issue and a different coating was the resolution in the end.

YMMV, Hope this helps.

scottbr
29th July 2023, 12:02 PM
Hmmm. I have used it on floors and they get wet occasionally.
This is what it says on their site:

The Osmo Polyx®-Oil The original Hardwax Oil surface is extremely tough and hard-wearing. It is water-repellent and dirt-resistant. The finish is resistant against wine, beer, cola, coffee, tea, fruit juices, milk and water etc

droog
29th July 2023, 12:21 PM
Hmmm. I have used it on floors and they get wet occasionally.
This is what it says on their site:

The Osmo Polyx®-Oil The original Hardwax Oil surface is extremely tough and hard-wearing. It is water-repellent and dirt-resistant. The finish is resistant against wine, beer, cola, coffee, tea, fruit juices, milk and water etc


Exactly the reason that those members on the RenovateForum used it on bathroom vanity benchtops, did not stop the fact they ended up with water marks and calls to the manufacturer for support did not resolve.
Suggest you call their support and hope you have better results from them.

scottbr
29th July 2023, 12:25 PM
That's disappointing.

I'll see what they say.

So if end up needing an alternative finish, what would you suggest that I might be able to apply over the Osmo?

scottbr
29th July 2023, 12:56 PM
Found this:

Osmo Polyx®-Oil and TopOil are microporous hardwax-oils with extremely high water resistance. The finish is proven against wine, beer, cola, coffee, tea, fruit juices, milk and water.
These types of liquid spillages will tightly bead on the surface without leaving any permanent marks, simply clean by wiping with a dry cloth. However, if these types of liquids are allowed to sit on the surface for prolonged lengths of time (more than approx. 15 hours) without cleaning, then marking can appear. Remove by partial sanding and re-applying the finish.

droog
29th July 2023, 01:09 PM
Having never used Osmo I cannot make recommendations for overcoating.

My preference for timber benchtops is one of the two pack coatings, in the past I have used Wattyl 7008 with great success.
I am sure there are plenty of other that have had success with alternate coatings.

qwertyu
29th July 2023, 08:41 PM
For this application the commercial makers who use osmo are using osmo wood protector first. But many of switched to Fiddes hard wax oil and it can be used as normal. I am also told that evolution oil is also suitable for this application

scottbr
30th July 2023, 02:53 PM
Bingo.
Too late to use Osmo wood protector (which I have never heard of) first, but I'll call the Fiddles people first thing tomorrow and see they say.
Hopefully a hard wax oil with better water proofing properties over another hardwax oil will be okay.
I will report back.
Thanks all.

scottbr
31st July 2023, 01:12 PM
I have ordered some Fiddles Hardwax Oil.
They were good on the phone.
Naturally did not say that Osmo is hopeless, because it isn't. I have used it for years with success.
She did say, as mentioned here, that commercial users don't have problems with using Fiddles in bathrooms.
But of course, if water is left for too long it would challenge any finish.
I have some leftover blackwood, so I will do a test of Fiddles over Osmo - with a sand in between.
Then I will apply some Fiddles on an untreated piece of blackwood.
Then I will do a water test on:
1. Osmo.
2. Osmo with Fiddles on top.
3. Fiddles

D.W.
31st July 2023, 10:41 PM
transition coat of dewax shellac if you can get the surface back to what you like, and then a coat of urethane over it.

Hardwax oils will probably be tolerant of drops of water for a little bit, but not standing drops. when polymerizing oil is used outside like linseed oil paint, the point if it is to have a breathable barrier and not one that's water and vapor tight.

I don't know anything about osmo specifically but very old oil can become cured and hardened enough that it would still perform well, but that's decades old. It's also the same reason that very old oils as a finish can become brittle. I suspect not much lasts long enough to get to that point.

finishes that claim water resistance generally mean you can accidentally spill something and clean it up quickly and not have an issue. Shellac is water resistant. It's not tolerant of longer contact unless it's very old and if it contacts water much before it gets there, it won't get to that point, either.

Keep a flat offcut of whatever you want to finish next time, let it dry for a little while, and put water standing on one end and a glass full of ice cubs on the other with a little bit of water primed under it. If you come back the next day and you can wipe off any water spots with a clean cloth, you're at a good starting point.

finishes for kitchens and bathrooms are generally a better choice for surfaces that will see standing water.

scottbr
1st August 2023, 11:34 AM
Thanks D.W.
Seems like I might need to bite the bullet and do what you suggest.
Always learning, huh.
I have a household of girls and standing water is a given.
I note that UBeaut have a dewax shellac.
What is your favourite urethane? I'll want a satin finish - not a fan of gloss timber.
I'll still do the comparison between Osmo and Fiddles because I'm curious and like hardwax oils.
Scott

havabeer69
1st August 2023, 10:51 PM
so do you have to keep re-finishing the wood? like a deck does is need re-oiling every year?

scottbr
2nd August 2023, 10:55 AM
so do you have to keep re-finishing the wood? like a deck does is need re-oiling every year?

It seems that if I left that bench finished with a hardwax oil, I would be doing it every year at least.
I have a birch ply kitchen bench in my Airbnb that I have not touched in 10 years and it's still good. Pity I can't remember what I used to finish it - likely a Feast Watson product from Bunnings, being just a DIY guy.
As for decks, I learnt a long time ago that finishing them just creates yet another thing to maintain. I have had a few of them. Embrace the grey timber look, I say.

r3nov8or
2nd August 2023, 05:01 PM
...
As for decks, I learnt a long time ago that finishing them just creates yet another thing to maintain. I have had a few of them. Embrace the grey timber look, I say.

I doubled-down on this concept last time, and installed grey Modwood :)

D.W.
3rd August 2023, 07:13 AM
Thanks D.W.
Seems like I might need to bite the bullet and do what you suggest.
Always learning, huh.
I have a household of girls and standing water is a given.
I note that UBeaut have a dewax shellac.
What is your favourite urethane? I'll want a satin finish - not a fan of gloss timber.
I'll still do the comparison between Osmo and Fiddles because I'm curious and like hardwax oils.
Scott

I don't generally use commercial urethanes, but rather crosslinked water based spray stuff if I need kind of high volume something or other that will be water resistant.

Any decent urethane finish that's specified to have high water and solvent resistance should be fine, though, and show no evidence of water contact other than minerals left behind - those that were in the water to start with.

You can get them in satin with flatteners without issue. Last year, I used a (solvent based) floor urethane that reviewers said has good durability and it was also satin - it looks good, is completely indifferent about water, and doesn't scratch easily. I'd use it without reservation on furniture if I used brush urethanes often - but it has suffered from VOC rules a little bit (more of a nuisance to apply - after the new solvents flash off, the result is good, though).

scottbr
7th August 2023, 06:01 PM
Thanks for responding, DW.

What was the floor urethane you used?

I went to Bunnings on the weekend and had a ponder.

I saw the Feast Watson wipe on poly, but that sounds too easy.

Scott

ubeaut
7th August 2023, 07:07 PM
Hard Shellac (https://shop.ubeaut.com.au/product/hard-shellac/) Ideal for any surfaces that needs protection from alcohol, water, heat, etc. Dewaxed white (bleached) Shellac with an added hardener.

When fully crosslinked it's about as tough as melamine bench top. Should look way better than the poly and be more durable.

Should go over the oil ok, (shellac has the ability to go over almost any surface) however, no guarantee as to what may happen down the track. Shouldn't be any problems but... You're getting well into unknown territory here.

Hope this is of some help.

Cheers - Neil :U

scottbr
8th August 2023, 10:59 AM
I'll buy some today, Neil.

I already have some U-Beaut dewax so I can add this to my collection.

I've never really used shellac, so it's about time.

And yes, I know I am heading deep into into unknown territory.

Thanks, Scott