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By KarenMakin
#1179778
Hello!

I'm reasonably new to both woodworking and brand new to the forum so apologies if this is too basic or been previously covered.

I'm trying to recreate (as closely as possible) the deep, rich mahogany finish of an older Victorian item on a newly created similar piece but I'm having trouble recreating the colour and finish. The new piece has been made from mahogany but I'm unsure what type.

Here's the two together (old on left, new on right)
IMG_5292.JPG
New one on right and old one on left


And here's a better pic of the colouring on the old one:
ghf.jpg
Better pic of colouring on old one


I've tried curing the new piece under UV lamps (50+ hours) which has certainly darkened it but not to the degree I'd like. I've also tried various combinations of Liberon Wood Dyes in both Victorian and Georgian Mahogany and also some Rustins Wood Dye in Ebony in for good measure but the colour seems to come out more brown than the deeper red hues I'm after.

I've also been told to use Morrell's Nitrocellulose spray laquer instead of French Polish as I'd find this easier to apply with me being a beginner. This goes on nicely and is creating shine but I wonder if the depth in colour on the original is in part due to the French Polish.

Whilst I realise I'll never get the 'aged' look perfectly without a 100+ years or so, you do see the finish and colour I'm after on lots of modern furniture so I'm hoping someone can help as I'm now completely lost with it!

Can anyone suggest a stain or finish type or combo and a final finish that'll get me the look and colour I'm after?

Many thanks in advance,
Karen
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By morturn
#1179787
Have a look for some Bichromate of Potash. It an old-fashioned stain that reacts with the tannin in the wood that accelerates natural aging and darkening.

I have used it under French polish many years back and it certainly gives a very rich tone to mahogany.

It is an oxidizing agent, so do take care, eye protection etc when using it.
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By custard
#1179802
The old one, assuming it's pre war, would likely have been a different type of Mahogany, either Brazilian or Cuban. Yours is either Honduran or quite possibly Sapele (which isn't a true Mahogany but is half the price).

No matter, as long as the grain structure is similar you can make any wood look pretty much like any other wood.

There's every chance the original would initially have been chemically stained. Potassium Permanganate or Potassium Dichromate/Bichromate of Potash, they're pretty much interchangeable and easily available. To get from your timber to the tone of the original timber you might want to add a dash of ammonia. Experiment on scrap, just a small dash of ammonia added to Potassium Permanganate is Cuban Mahogany in a bottle! Even lacquer spraying on top of this will get you more than half way towards the original.

If this was a studio camera it would probably have been french polished. Use a garnet polish and after the initial grain filing you can then adjust the colour any direction you want with spirit stains. If you want to add some age the easiest way is by mixing up a wax with some very dark brown/black earth pigments plus some rottenstone to mimic the dust that always gets trapped in old wax, apply but rub away completely from the highlight/proud areas and just leave the residue in the quirks and depressions. If you're new to french polishing this isn't the project to learn on. French polishing isn't rocket science, but it does take lots of practise, this job is too small and fiddly for a beginner and there's a tricky combination of brush and rubber work. But you're right, some of the colour is coming from the polishing process. Maybe talk to your local antique restorer.
By KarenMakin
#1179823
Thank you so much - that is incredibly helpful.

I'll try the Bichromate of Potash with a dash of ammonia on a test piece and see if I can get the colour needed and I'll get some quotes for the French polishing from an antiques restorer. If they come in out of the budget so to speak I'll have to put this one an hold and start practicing on plenty of other items first...better slow and spot on then rushed and wrong hey!

Thank you also for the aging advice - I'll certainly try that once the finish is on.
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By morturn
#1179933
I tend to steer away from potassium permanganate. It’s does look great when first done, is cheap and easy to use. But, the colour migrates in sunlight very quickly, and turns to a silvery grey cast.
By KarenMakin
#1188151
Sorry for the delay in posting a reply!

Firstly, many thanks for all of your help. It's been incredibly useful!

Having decided to try the Potassium Dichromate first, I had the devils own job trying to track any down....apparently it's now a restricted substance! I'm hoping I've now got a 'ready mixed' version on the way to test on a bit of scrap. If that doesn't work I'll try the ammonia fuming and potassium permanganate and Osmo next.

I've also put some additional embellishments on the camera to bring the design more in keeping with the original and found a lovely gentleman who is going to look after the French Polishing once I've got the colouring right (you were very right that this isn't a beginners piece. I'm now on my 5th polished project...maybe in another 50 or so I'd be a little more ready!)

I'll keep you posted along with a pic of the finished article!
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By custard
#1188303
KarenMakin wrote:Having decided to try the Potassium Dichromate first, I had the devils own job trying to track any down....apparently it's now a restricted substance!


Then try this, it does the same job

https://www.ebay.co.uk/itm/500-grams-Po ... Sw7NNT6hI2
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By Eric The Viking
#1188327
MarkDennehy wrote:Not to mention, if you have problems with your feet like athletes' foot, soaking them in potassium permanganate solution is a well-known treatment, so it's handy to have round the house anyways :D


Just curious: does it turn your feet dark brown or bright purple?

It is jolly poisonous, which is why, I assume, it works on fungus. But I'm as keen as anyone else to see how Karen gets on with her staining, as I've got some stuff I'd like to do, too.

AndyT: I'll be round directly to blag a bit of your PP to experiment with! :-)

Seriously, this is a good and really useful thread for anyone like me. I don't do enough of this sort of thing to have built up any experience, and when I have stained mahogany in the past, it's only been to darken down stuff that was bought new but in different batches: and I was only trying to reduce variation.

I noticed the different "colour" of the top rails too, but I think it's down to the finish and the lighting. It's catching the light, and the varnish filling the grain probably has a slight cats' eyes effect. It's either coming from the camera flash or the top lighting - hard to tell - but the other rails are sufficiently off-lens -axis for it not to happen. And because of the moulding finish to the top, you get a highlight that masks any similar effect.

Of course it might just be coincidence :-)

E.
By phil.p
#1188337
A sort of purple tinged brown - I used to do my feet with it, it looked a bit as if I had shoes on when I was barefoot. I was advised to use the stuff because I had the nasty athlete's foot that travelled under the skin and erupted in blisters all over the feet.