Thread: French polishing questions

UBeauts Foodsafe Plus data sheet suggests that it can be used as lubricant to stop sticking when french polishing and maybe of some help.

Not an expert in FP, so cant offer much wisdom there.... but 100% metho can be obtained from most dedicated paint stores. They call it "IMS".

At my local place (called The Paint Place in Philip and another in Mitchel) it is 1L $9.95 and 4L $24.95 both made by Sceneys in Melbourne.

Hi, hope you get the hang of it, it's worth persisting. I can only highly recommend Neil's (our Benevolent Dictator) Polishers Handbook, I learnt how to French polish by following the instructions meticulously. Did you fill the pores? Essential for that mirror flat glassy finish. Anyway, it's all in the book, also worth searching French Polish posts in this forum. Lots of rubbish on the youtube, but this one How to French Polish - Woodworking Finish with Shellac - YouTube is fantastic!

If you were working on your piece last week, it was just about the worst FP weather imaginable - humid as heck. I normally prefer to FP in the cooler, drier months when you get faster drying & stabilising after a rub-down, but I too was polishing & it was slow-going. (I was finishing my entry for the Wootha competition, now cancelld! )

I've done a fair bit of FP over the years, but don't consider myself an expert by any means. I did think I was getting pretty good at it once, but then I saw the work of a fellow club-member (a trained pro) and realized I have only begun! But fwiw, I'll give you my 2c worth. From your description, I think you were just pushing it too quickly and not letting it dry adequately before the next rub-over. Also, in very humid weather, I break the stock polish down more, 50/50 is ok for initial filling, but something like 60 (alcohol) to 40 polish is better for the polishing stage in humid weather. It's slow-going and you'll need more 'coats' but it sets quicker & minimises swirl marks. I go over the surface with the rubber in the prescribed circular pattern, then finish with long straight strokes, turning gently at the ends so as to not lift the rubber off the surface. If the rubber starts to stick, stop immediately & let it set. I was finding I could only safely do a rub-over about 3 times per day on those very humid days we had (before it went weirdly cold for this time of year - it's like Melbourne weather!).

If you make a mess there are several ways to sort it. Sandpaper is useless, it will fill & clog in about two swipes. I have read recommendations to use wet & dry with a light oil but never tried it, it seems to me you'd spend more time cleaning up the mess than its worth. My preferred method is to use a very sharp card scraper & carefully scrape the offending area smooth. It's a bit tricky if you are not used to card scrapers, & all too easy to get deep marks from the corners so practice on a test piece first. The advantage of scraping is that it won't remove whatever you have managed to push into the pores and the surface will re-build quickly. A safer, but somewhat more brutal way is to use 0000 steel wool and cut the surface back (make sure it is thoroughly 'dry' first). Also make sure you remove all the tiny bits of steel that get everywhere, and only use good quality steel wool made for finishing, that doesn't have oil or detergents in it.

If you want a super shine, the way to achieve that is to let the polish harden up for a couple of days or so, then use a clean rubber barely moistened with a spray of alcohol (just a hint of alcohol, it definitely should not feel 'wet'). Go over & over the piece, occasionally refreshing the tiny amount of alcohol in the rubber, until the surface is perfect. Depending on how deep the swirl marks or defects are, this will take anywhere from a long time to forever....

Cheers,

It's been a few years since I have done any French Polishing, I still have some blond flakes in my workshop and mixing your own is way better than buying off the shelf. I used to build up the layers and use pumice powder to grain fill. My French polish teacher at collage all those years ago taught us to apply it in a figure 8 motion. I think from the pic you are getting too much shellac onto your piece from the pad, also the pad needs to have a flat'ish area of say 25 to 40mm in diameter (depends on size of piece you are polishing) which comes in contact with the piece you are polishing, a smaller pad can get a build up of shellac around the perimeter quicker and with a smaller pad area to work with it is harder to stop that old thicker sticky shellac from making contact with your piece. When building up the layers you will see areas that look shinier than others this means the shellac is sitting on the surface better due to the grain in this area being filled, you need to keep building up the layers and filling the grain until all the piece looks consistently shiny. You can use oil to help lubricate the pad, the oil will not mix with the shellac but say on the surface of your piece and can be removed right at the end of the polishing process using a very small amount of alcohol wiped over the surface of the piece.

I may be able to help you. I have been taught by a professional although I don't do much of it these days. I am in Hawthorne Brisbane, if that is convenient send me a PM with your phone Number and I will contact you. John

Good advice, camelot. What you do is 'genuine' french-polishing and the method most often described in old texts. The alternative to adding pummice as you build is to grain-fill before starting, which is the way I was taught. It's the 'easier' way, but most fillers tend to cloud the wood & don't get as clear a finish as adding the pummice as you go. On finer-grained woods I prefer to fill with the polish itself, which takes longer, but imo gives a clearer finish. Woods like Qld Maple (which appears to be what the OP is polishing) have very large pores & really need filling one way or the other if you want a glass-smooth finish.

And I hesitate to say it in this forum (sorry Neil) but I have found the pre-mixed polish is a bit harder to work with than home-mixed from flakes, too. It doesn't seem to firm up as much between rubs, and is more likely to stick & pull if you push things too quickly, so if you are a newbie at polishing it's easier to get into trouble. However, it's damned convenient, has a better shelf-life when mixed, & much more convenient when you only polish small items occasionally as I've been doing these last 10 years or so....
Cheers,

PS: Forgot to say that oil will help a lot when you start out. We were taught to use a dab of BLO every now & then, as needed. Just touch the oil with your finger & wipe it on the rubber - it will make the rubber glide across the work. As you become more practised you get better at judging the feel of the rubber & how much pressure to apply & use less & less oil..

Originally Posted by Swifty

Lots of rubbish on the youtube, but this one How to French Polish - Woodworking Finish with Shellac - YouTube is fantastic!

Aha, that's exactly the one I watched earlier this week, and yes, this is the video that got me from 40% to 90%! It's a really good demo of the process.

Thanks for all your hints. I was wondering if the pre-mix might be a little slower drying, and this could certainly be part of my issue, as that's really what it feels like. I'm using this white shellac on parts of the project, and plan to get some dark shellac for other parts. I have some Feast Watson orange flakes, and used some, but I can see a very slight green tinge in comparison to other parts of the piece, so I'm not sure what's going on there. It maybe needs just a half-drop of red-brown stain to colour match the rest of the piece.

@IanW, thanks for the suggestion of the scraper. I absolutely LOVE my card scraper, and will give it a go. I'll make it nice and sharp and take light strokes. As you said, sandpaper is almost useless, and very frustrating. I did try 0000 steel wool on another section, and noticed the day after, my polish pad was covered in black spots, which I assume was tiny pieces of steel wool that rusted away overnight. I don't want that to happen to the finish, so I'm either avoiding steel wool altogether, or wiping down the finish after. I'm not sure if the steel wool was responsible for the slight green tinge in the flake shellac.

I'm not sure what the wood is, but definitely not Qld Maple. It is an antique made in Indiana USA, so it will be a local wood over there. It was previously polished, and after scraping the old finish off, the wood was super smooth with hardly any open grain. Most of the piece is black walnut.

Wet and dry sandpaper (600-800 grit) works a treat for smoothing the surface if you lubricate it with turps.

Sorry for the delayed response to this only just saw a notification about it this morning and just got to it an hour or so ago, so...

Hello surfdabbler, here's my thoughts.

From the it looks of the pic it's been a bit too much shellac and too wet.

100% IMS (Ethanol) is preferable to 95% and usually available at any half decent paint shop but often only in 4 lt tins instead of 55ml or 1lt although looking at woodpixels link to Sceneys Melb they have 1lt listed.

"A Polishers Handbook" can be of great help and has set many people on the right track for all sorts of polishing.

Using oil as a lubricant is an almost essential part of the polishing process especially for a good high shine. As for the oil to use I recommend our FoodSafe Plus oil which is high-end medical grade heavy paraffin oil. Traditionally polishers used BLO or or standard linseed oil. Both if left on the surface of the work can skin if left overnight especially BLO which has a drier in it.

Foodsafe being a non drying oil so at the end of the day you can (shouldn't but can)leave it on the surface and go on holiday for a month come back and pickup the work where you left off. Like you had gone for lunch and come back.

The other good thing about the Foodsafe is that a little of it gets trapped in the matrix of the polish which won't hurt the finish in the slightest but will serve to enhance it and make the grain pop especially if the wood has any figuring like fiddleback, burl or flame etc.


I'm using predissolved white shellac, use by date is August 2023. I'm thinning it down 2-parts shellac with 1 part metho.

That shellac is a 3lb cut so a little stronger than others which are usually around 2lb cut and mixed with 95% IMS instead of 100%. Best starting point is to take some out of the bottle and mix it with equal parts IMS.

You can also cut some of that mix 50/50 with IMS for use later on in the polishing process. If brushing it on then start with weakest and progress to 2nd weakest and finish off wit one coat of full strength shellac.

I'm using 100% cotton wadding for the pad, If it's white wadding where the hell did you get it. Been trying to get some for years ever since they said there was no longer a need for it and went to the coloured stuff which can also have all sorts of other stuff in it like bits of wire metal shavings etc.
wrapped in 100% cotton weave, similar to t-shirt material.Good, but worn linen or cotton is better.

My pad is quite small for this project, about the size of a big thumb, and that is certainly working better than a larger pad.Too small twice the size would be better. More surface coverage and way less witness lines from the application. (Witness lines or marks are the marks left behind by the rubber hence the swirl marks.)



The drawers are small, so I have several drawers on rotation, doing one pass on each, so each pass has more time to dry before I go back over with the next pass.If you have the right amount of shellac in the rubber you should be able to go over each draw at least 2 or 3 times before moving on to the next.

Previously, I've tried to do too much shellac, and the pad was getting a buildup of smooth shellac on it, but I've dropped back the amount of shellac, and using more alcohol, and this has greatly improved things.Hence the reason to do the cuts of shellac with metho, as above.

Also, if the finish is not smooth, does this make it more likely to crackle in the future, or is that unrelated?
Unrelated, crackle usually comes about by having incompatible finishes, movement in the wood, and sometimes polishes used over the top of the shellac.


Is it OK to just sand the surface and keep working it until it gets smooth, or is it better to take it right back and start over?Personally I'd be inclined to sand with wet n dry using water with a drop or 2 of dishwashing detergent added as a wetting agent. This stope the abrasive from clogging.


you can use the wet n dry with turpentine (mineral not pure) or white spirits and this will make the abrasive cut a little more aggressively.

If you cut back to bare wood make sure the entire surface is cut back to bare wood if you have some that is still showing and start to polish again you may well get blotchy effect as the first coat will be the first coat to the raw wood. Whilst it could be the second or even the third coats going onto any that was left on the surface. This will give shiny and dull sections throughout the rest of the finishing process.

On use of the rubber: start off with small circles then figure 8's then large ovals back to medium circles elongated figure 8's then straighten out with the grain with long tight ovals from end to end then straighten out again by gliding rubber onto the work from one end and glide off at the other end do this until the entire surface has been covered. DO NOT DO THIS WITH A WET RUBBER!

NEVER LET THE RUBBER STOP ON THE SURFACE EVEN FOR A SPLIT SECOND.

Hope this is of a little help to you and anyone else having problems with French polishing.

Cheers - Neil

Originally Posted by IanW

And I hesitate to say it in this forum (sorry Neil) but I have found the pre-mixed polish is a bit harder to work with than home-mixed from flakes, too.
No offence taken Ian. However we're talking White Shellac (dewaxed) here and there is a reason why it is premixed. White shellac has to be kept at a constant 8C or below in its raw state. That's why we won't supply it raw to distributors or customers.

That and the fact that almost all our white shellac is reserved for making our friction polishes. if you happen to see white shellac in its raw state for sale in a shop think twice before purchasing. It only needs a few hot Melbourne days and it could be ruined. It won't properly dissolve and will need to be strained really well before use as what's left undissolved will ruin the finish.

I have seen supposed experts on YouTube showing how to remove the solid bits from freshly dissolved white shellac. Saying this is common and won't have any affect on the shellac.

Rubbish... it's been stored wrong, is heat affected and shouldn't have been sold to you. You dumb YouTube guru.

Originally Posted by surfdabbler

.........I'm not sure what the wood is, but definitely not Qld Maple. It is an antique made in Indiana USA, so it will be a local wood over there. It was previously polished, and after scraping the old finish off, the wood was super smooth with hardly any open grain. Most of the piece is black walnut.

Ha, provenence is everything! I just looked at the thumbnails and thought, "OP in Brisbane; looks like Qld maple; that must be it". It always pays to look at the full-sized pic! I'd bet London to a brick it's Maple (Acer sp.). Probably one of the "soft" maples, they can be very hard to tell apart by appearance.

So now you know why they call it "Qld maple" - it's very similar on a casual look, but much coarser-grained & I've not seen those fine brown lines through it like you get in "real" maples...
Cheers,

Neil thanks for your detailed reply. I've been doing more polishing today, and it's going much better, thanks to all the advice. I'm leaving longer between passes, and working in small sessions. As you said, I'm finding I can go over the same drawer a couple of times before I have to move onto the next drawer. I can rotate through all six drawers quite a few times before taking a break. I'm getting a feel for how far I can go before problems arise.

@IanW, the scraper worked a treat, but only on flat surfaces. I might also try a wet sand tomorrow. I was wondering about detergent vs turps, but it sounds like they both work. Hey, interesting story, I was polishing a few days back, and wondering why it was coming out really streaky and like white smoke on the finish...turns out I had accidentally diluted one batch with turps instead of metho! The turps is now on the other side of my workshop.

Anyway, I did have good success today, and it's building up to a much better finish now, albeit slowly.

Originally Posted by ubeaut

100% IMS (Ethanol) is preferable to 95% and usually available at any half decent paint shop but often only in 4 lt tins

I'll call some local paint shops to see what I can get tomorrow. If I have to buy 4L, so be it!

Originally Posted by ubeaut

Best starting point is to take some out of the bottle and mix it with equal parts IMS. You can also cut some of that mix 50/50 with IMS for use later on in the polishing process.

Yes, I've been adding extra spirits directly to the pad to dilute the mix. I will mix some up to your ratios tomorrow, because I agree and think it will work well.

Originally Posted by ubeaut

I'm using 100% cotton wadding for the pad, If it's white wadding where the hell did you get it.

Yes, it's white. My local spotlight has rolls of it. I'll also head back sometime and get some linen, as everyone seems to recommend this.

Thanks again for all the suggestions.

Originally Posted by surfdabbler

......@IanW, the scraper worked a treat, but only on flat surfaces. I might also try a wet sand tomorrow. I was wondering about detergent vs turps, but it sounds like they both work..

Oooh yeah, I definitely meant using the scraper on the flat parts, it would be a bit savage on curves, but I do use the scraper corners (carefully) to smooth any buildup on inside corners. Curves & mouldings sort the men from the boys when it comes to polishing, they are much more of a challenge to get perfect. I'm still a boy in that regard.

Originally Posted by surfdabbler

......Anyway, I did have good success today, and it's building up to a much better finish now, albeit slowly..... .

Slowly is the essence of french polishing. The way I think of it is that we are applying such ultra-thin coats on each pass that any imperfections are very, very minor, and cancel out as you proceed with more. "Speed" comes with being able to judge how soon you can rub over again, but unless it's your living, or you are working to a deadline, it's far better for the occasional polisher to take it very steadily. The job goes more smoothly & the end result is usually better too. I don't always heed my own advice, of course, there always seems to be some sort of deadline...

Linen is what the old books always recommend for wrapping the rubber. I've certainly found that it's better than cotton in that it's tougher & takes longer to wear through to the point where little dags of wadding start getting through & sticking on the surface (which occasionally happens even though I watch the thing carefully!). But last time I tried to buy some linen cloth, all I could get was coarse-woven stuff that wasn't at all suitable. So mostly I use good-quality cotton & double it over.

A useful trick I picked up from another old bloke was to keep a spray bottle of metho on the bench. After the initial filling coats are done & I'm starting to get some build, I rub over a section with the shellac-charged rubber, and as it gets dry & starting to grip a bit, give the rubber a quick spray (just enough to barely dampen it, it should certainly not feel wet) & go over again. This helps keeps the surface more even as you go It needs to be done with care, if you wet the rubber too much it's likely to dissolve the fresh shellac & make a big mess, but once you learn to judge it, it's a very useful technique, it keeps the surface smoother & reduces the amount of work at the end "spiriting off" to get that perfect glassy finish.

You seem to be getting the hang of it pretty quickly, french-polishing isn't the easiest finish to do well, and I don't claim to be an expert by any means, but there's no mystique to it - when things go wrong there's usually a pretty simple explanation....

Cheers,