High-gloss, hard-wearing finish

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Jelly

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I'm just starting on a project which will culminate in needing to finish a coarse open grained wood (Meranti), with a much finer grained inlay (Sycamore), the aesthetics call for a glass like finish, not unlike the appearance of French Polish.

I also own french polished furniture and whilst it's lovely, it's also vulnerable to damage, which I'd rather avoid in this piece.

I've got access to a spray booth and sprayer, so was considering acid-cat laquers, of which I have no experience. Before I just buy a small quantity to do some tests with (it's not cheap!) Am I barking up the wrong tree entirely? My fear is that the laquer will give a high-build, plasticy look which will be wholly incongruous.

I'm also trying to work out how to subtlely darken the Meranti to a deep red-brown whilst keeping the Sycamore creamy white, I'm assuming stain or dye the components after preparing them to receive the inlaid pieces, but before fitting them.

Up to now I've used a mix of Shelac and Rosin (Colophony) dissolved in Double Boiled Linseed as a varnish, which works wonderfully, but crucially doesn't give a high enough sheen, not to mention that it takes a week or so between coats, and a month or more before it fully cures.
 
You're not making it easy on your self using Meranti can't you find a bit of Brazilian mahogany or even use sapele, then you could use a chemical stain to darken the mahogany.
 
Chrispy":1nfbw3nx said:
You're not making it easy on your self using Meranti can't you find a bit of Brazilian mahogany or even use sapele, then you could use a chemical stain to darken the mahogany.

In a word: No, I can't. :|

The Meranti is a reasonable compromise, low price (£900/m³ for 100mm thick stock), availablity of large sectional sizes and workability were all key factors in choosing it, and I knew I'd have to suck it up with the coarse open grain when it came to preparing to finish it, and getting the desired results.
 
If I made a meranti ukulele with sycamore binding, I'd assemble it all, pore fill the meranti, scrape back and then:

- two wiped on coats of clear shellac over the binding. Once dry, scrape back to bare meranti at the join.

- multiple coats of brown shellac over all, until I was happy with the colour.

- scrape the brown shellac off the sycamore with a chisel, then apply clear shellac.

- sand level then apply desired finish. Pretty much anything should go nicely on this, so I'd select depending on durability, desired film thickness, etc.

You could spray lacquer, and with the levelled surface wouldn't need to go so thick as to look plastic.

I'm not saying this is right for your application, but it might help inspire your own solution.
 
I wasn't aware that Shellac would go into an oil based varnish.
How are you making the Shellac, rosin and linseed oil varnish? Are you heating this until you reach the long string stage? You will also need to add a drier and/or subject it to lots of UV to get it to dry and harden in a reasonable time.
Any resin/oil varnish should be able to produce a pretty glossy surface if you go through the grits/polishes, providing the oil to resin ration isn't too high. In any case these sorts of varnishes aren't what one call hard wearing. You really have to go to the short amber/copal varnishes or the harder synthetic resin varnishes to get hard wearing. Behlens used to do a synthetic oil varnish that was really hard and tough. Dried fast too. I suspect that a lot of the stuff sold as 'table top' or 'bar top' varnishes will be very similar too.
 
Jelly":2x420ez9 said:
I also own french polished furniture and whilst it's lovely, it's also vulnerable to damage, which I'd rather avoid in this piece.
There's actually quite an easy solution to this that's not uncommonly used these days, which is to apply poly or another waterproof finish on top of the shellac.

Even one wiped-on coat of poly makes a difference, two or three gives fairly thorough waterproofing and significantly improved scratch resistance.

Jelly":2x420ez9 said:
Am I barking up the wrong tree entirely? My fear is that the laquer will give a high-build, plasticy look which will be wholly incongruous.
Easy way to avoid that: don't spray it as heavily :)

Acid-cat lacquer is a lovely finish but you have to be realistic here about what look you actually want. Apologies in advance if this is teaching granny to suck eggs but any fully built high-gloss finish can be described as plasticy by some viewers, regardless of what was used. I've read people describe French-polished pieces as "looking plasticy"! This is when they knew shellac was used, not out of ignorance assuming the finish was poly or another 'plastic' finish.

I've seen shellac, acrylic coatings, the Rustin's stuff whatever it is, epoxy, natural-resin varnishes, LMW varnish, alkyd varnish, phenolic varnish, uralkyd (poly), and various lacquers all built to a full finish and there was in reality very little to choose between them (excluding variation in the colouring of the wood nautrally).

Jelly":2x420ez9 said:
I'm also trying to work out how to subtlely darken the Meranti to a deep red-brown whilst keeping the Sycamore creamy white, I'm assuming stain or dye the components after preparing them to receive the inlaid pieces, but before fitting them.
Dye would be the obvious thought here but you might be able to use chemistry. Many alkalis will colour woods in various ways, with African mahogany for example you get a notable increase in the redness. You can use a solution of baking soda or washing soda. You can also test out caustic soda if you're okay with working with it.

I don't know the effect on meranti but worth a quick test. If the result is acceptable it's possible you may be able to do this with the sycamore in place as there may be little effect on that species.
 
Do you really need to completely fill the grain on the Meranti?

I do quite a lot of stringing/inlay and, as long as the stringing is relatively fine, I personally don't grain fill. This is Sycamore inlay on Tiger/Brown Oak, which is even more open grain than Meranti,

Tiger-Oak-Table-1.jpg


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What is a bit tricky though is that when inlaying across the grain, on any piece longer than about 50-75mm I also cut the inlay cross grain too, so shrinkage won't cause it to pop out. Cutting and fitting 1mm wide cross grain inlay is quite fiddly, but it can be done.

Good luck!
 

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A 'trick' we use on guitar inlay is to squash the veneer prior to inlaying it. You literally run a hard piece of wood over the inlay which compresses the wood slightly. A water based glue (I use Hide) is run into the groove and the inlay is pressed or hammered into position. The water based glue expands the compressed inlay making for a very tight fitting.
 
custard":49k4xam8 said:
Do you really need to completely fill the grain on the Meranti?

...

What is a bit tricky though is that when inlaying across the grain, on any piece longer than about 50-75mm I also cut the inlay cross grain too, so shrinkage won't cause it to pop out. Cutting and fitting 1mm wide cross grain inlay is quite fiddly, but it can be done.

I'm seriously impressed at the craftsmanship involved, and the length you're willing to go to in pursuit of perfection; the little table you used as an example is also wonderfully proportioned, with just a whisker of curvature.

With regards to filling the grain... Currently experimenting on offcuts to work out what gives the best effect. I'm inclined to avoid grain filling, if only because it would be a nightmare to do well on the carved elements... Using initial 'high build' coats of finish, and sanding back to give smooth surfaces seems like it might be a better approach, either way the large open pores will make achieving a thin but glassy finish a bit of a challenge. (Unless you're suggesting accepting the aesthetic and tactile nature of the material as part of the finished piece, rather than fighting it... Which I hadn't really considered.)

Filling the surfsce by gently sanding the prepared surface for a second time immediately after wiping on a generous coat of thinned linseed oil varnish (tung based might be better if I take this route) has given a good result on a test piece but I'm dubious of the durability.
 
I have just finished a box with wipe on poly, and it has come up like glass. I'm very pleased with the result, and it just couldnt be easier to apply.
 
I havent been able to find any ready made wipe on poly on the island, so i mix my own.

you tube has very conflicting advice, but with trial and error (quite a few errors!) i have now got what I'm happy with.

Get a little throw away plastic cup, buy some clear gloss polyurethane paint ( MUST be oil based! Water based is a pig to work.)
and ordinary white spirit or thinners. put in 2/3 poly to 1/3 thinners and stir. I only coat a small box at a time so I use a tea spoon to measure with. 2 of poly, 1 of thinners. After mixing well, just wipe on with a folded paper towel over a clean surface.

I did this dozens of times and failed with the finish, until I was told the trick.

Heres the trick that a Kentucky man called Malcolm gave me from another web site, and its against ALL you tube advice.

DONT WIPE IT OFF.

Hard to believe, but it works. Put it on reasonably thick, but just remove enough to stop it running. Leave the swipe marks, they will all come out in the drying.

immediately place it somewhere dust free. I place an upside down cake tin over them as my boxes are fairly small and they have to stay in the garage due to smell. Leave it for 24 hours. Dont peek, dont fiddle, walk away.

If its not shiny enough for you, do it again without sanding. I find my 3 teaspoons worth in the plastic cup will last two days without even covering and that will coat two or even three times. That must be cheap enough for anybody.

I am so pleased with the finish.
 
Glad its come out well for you.
Cant claim the credit, it was told to me, but if it works I'm not too proud to use it. (lol)
 
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