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smerdo
13th March 2015, 10:59 PM
Hi there
i have a wonderfull Jarrah slab and I've finished it with bondall monocel clear timber varnish SATIN. this has made the timber very dark altho Jarrah is a natural dark timber i wanted the natural red colours more so than a dark colour.
My friend has a slab from the same tree finished with a 2 pack clear lacquer (first picture) and his finish and colour is what i wanted
Can someone tell me where i went wrong ?
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Note the picture with my clear and how the stirring stick kept its original colour.
My friends slab has had 4 coats sprayed on of lacquer. mine has had 2 unthinned coats with a brush
Any advice would be appreciated before i break out the sander

Master Splinter
13th March 2015, 11:49 PM
Nothing you can do for it now aside from breaking out the sander. Make sure it's had plenty of time to dry otherwise you might have lots of clogged up sandpaper on your hands!

I've always found that lacquers will give a lighter finish than an oil based varnish; I attribute this to the oil content soaking deeper into the timber, while the lacquer sits on top. (I particularly like automotive clear if I want the clearest possible finish as it's the closest I've found to 'clear', not amber like oil varnishes, or blue-ish like some of the water based varnishes).

Always test a finish on a timber if it's first time you've used it - generally what you see when it hits the wood is the finish you're going to get, and no, it's not going to change too much when it dries.

I would expect your mate's slab to slowly loose its red colouring over time, getting closer to a jarrah brown. (I've been meaning to test the idea of using red stain to re-red old jarrah, but haven't had anything to test it on!)

smerdo
14th March 2015, 12:10 AM
Thank you for your reply
Can i use a lacquer followed by my polyurethene as it is a outdoor item and i want it to be hard wearing ?

Master Splinter
14th March 2015, 12:39 PM
If you like the finish on your mate's slab, I'd suggest using whatever it was that he used!*

Hard wearing for outdoors (for me) consists of: 3-4 coats of marine epoxy followed by 2-3 coats of polyurethane to protect the epoxy from UV. (the epoxy provides the water protection, the poly is just there to protect the epoxy from UV, as that's the Achilles heel of epoxy).

Either way, expect to redo the poly (scuff sand and recoat) on weather exposed surfaces every couple of years to keep the protection up.

And always do a test piece to make sure that the final finish looks the way you want!

*If by two-pac you mean isocyanate two-pac, and it was applied by spray and you want to do the same, add a quality (Sundstrom or similar) face mask and organic vapour cartridge (cartridge $30, mask $40) and one of those disposable suits to your shopping list. Don't use the cartridge for more than about four hours till you retire it to 'non-iso' use only (you can't tell by smell when the cartridge is letting isocyanate vapours through, so it's best to consider them a use-once proposition). Or get your mate to finish it!

mark david
14th March 2015, 02:20 PM
I have used Becker Acroma DM307 on jarrah with a 30%gloss which gives a nice finish
I sprayed mine outside as I dont have a spray booth.