French Polishing - Attempt #2

[woodPixel]

I've been enjoying the thread by @SurfDabbler over here: French polishing questions (https://www.woodworkforums.com/f9/french-polishing-questions-245939)

and rather than poison that thread, I'll create my own poison :)

Some things I've learned:

-- Sounds easy
-- Is not easy
-- Its not about the layers, but the smoothing/stretching technique
-- Wetness of the mouse is bad
-- One must fill the pores beforehand
-- a glove is important, unless one likes pretty nails (it does work rather well at that!)
-- seems that 3 coats per session is about all it can handle
-- I did try mineral oil, but that ended up.... badly
-- Its important to wait between sessions for the last layer to stiffen/harden sufficiently before another, too fast = bad

Now, I have a few things missing:

-- I don't have any fancy powders, such as FFFF pumice or talc. This obviously needs to be overcome :)
-- The lighting is ordinary
-- The timber is merbau, which is just a scrap

So!

My first attempt can be seen here: Hand scraper heat (https://www.woodworkforums.com/f152/hand-scraper-heat-246473-post2275523#post2275523)


and this thread is my second.... with each image representing one distinct "coat" or stage.

Image 1 is where I sanded the old bodgy FP attempt off.

I used Abranet 80 grit on the Mirka Ceros. I was informed that sanding off Shellac is a disaster, but I found the opposite... the Abranet handled it perfectly.

Ive not yet finished...

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The cat (Chuppi 14) seems to like the smell of Shellac.

Now to go back and re-watch those videos and review the threads and apply some learnings!!!

[labr@]

The cat (Chuppi 14) seems to like the smell of Shellac.

It's not the smell of the shellac WP it's the metho - I think you need to face the fact that your cat is an alcoholic :wink:.

I've only had 1 go at FP and found that the shellac would fill pores ok without pumice or other fillers. However, like you, I did find that not leaving long enough between coats was problematic. I ended up with a piece that would take on the imprint of a piece of cloth if left sitting there overnight. This was a small light piece so the shellac layer must have been very soft.

Looking forward to more instalments.

[woodPixel]

It's not the smell of the shellac WP it's the metho - I think you need to face the fact that your cat is an alcoholic :wink:.

I've only had 1 go at FP and found that the shellac would fill pores ok without pumice or other fillers. However, like you, I did find that not leaving long enough between coats was problematic. I ended up with a piece that would take on the imprint of a piece of cloth if left sitting there overnight. This was a small light piece so the shellac layer must have been very soft.

Looking forward to more instalments.

I've two idea planned for the upcoming challenge. Both will need FP, so its good to get practice in. PLUS it can be done inside, doesn't need spray gear nor special setups. The ethanol has zero smell, so Loving Wife doesn't get cranky about my various stinks :)

I was thinking of using shellac as a pore filler or de-fuzzer/grain-stiffener in the next jobs too. It seems to work very nicely for that.

On re-reading all the old posts a lot more of what was said is finally sinking in. My old scone has become ossified in its age, like poor old Chuppi ... too much Metho :)


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[homey]

wP,

A few thoughts.

Grain filling. While shellac alone will fill the grain, open-pored timbers take so long I prefer using a grain filler. I use Acquacoat which dries quickly (very). I find it more transparent than filling the pores with pumice/wood dust. Just my preference.

Mineral oil. I do use this, but only a drop to stop the rubber sticking, then again when the rubber starts to ‘pull’.

Yes - a wet rubber in not a good thing. :o Just barely moist. I test it against the inside of my forearm. Once the surface is complete the oil can be removed by spiriting off with the rubber now containg mostly metho.

FP is one of my three favourite finishes along with hardwax oil and spray NC lacquer and I love the quiet rhythm of it. Took me a while to get used to it but now it’s almost effortless. Not flawless just effortless :D

Regards,

Brian

[woodPixel]

Grain filling. While shellac alone will fill the grain, open-pored timbers take so long I prefer using a grain filler. I use Acquacoat which dries quickly (very). I find it more transparent than filling the pores with pumice/wood dust. Just my preference.

Mineral oil. I do use this, but only a drop to stop the rubber sticking, then again when the rubber starts to ‘pull’.

FP is one of my three favourite finishes along with hardwax oil and spray NC lacquer and I love the quiet rhythm of it. Took me a while to get used to it but now it’s almost effortless. Not flawless just effortless :D


I'm enjoying it too. Its breaking up the day quite nicely.

On Acqucoat - by jiminy - why didn't I think of that????? I used it for EXACTLY this when I was doing boxes!

I'm so stupid! Id use the Acqucoat, smooth it, use either CA or epoxy for two, perhaps 3 layers, fine block sand and then polish. Perfect result every time. (trouble is = stinky!)

I'll try another piece with it. Ive even the tub in my drawer here.... (argh!)


On oils, I also love NC. I used it HEAPS in the past. Love it. So easy. Also, I've a fair bit of Kunos Livos which is amazing.

[Swifty]

Stick with it wPix. I am also doing some FP for a current project, my FP kit is shown in the picture below. I keep my rubbers in the glass jam jars, the screw top lids have kept the rubbers moist and usable for the last year or more. Then I have sauce bottle type containers for the paraffin oil, shellac and alcohol. The little linen bag or pounce bag contains the 4F pumice powder that I use for pore filling. The pounce bag is struck onto the wood surface and delivers a small amount of pumice that I then grid in with the pad, mostly alcohol in the pad but a little bit of shellac also.

This was a test piece I did, in preparation for completing a clock, it was the first time I tried using AquaCoat. I overthunk it and botched it a bit, but it turned out okay after I competed the pore filling with the traditional pumice method over the top of it.

The pore filling is really important if you want to achieve a mirror finish, which can be seen in the first photo, the reflection looks OK. No way it would look like this without the pore filling!

I always need to keep reminding myself that straightening out at the end of each session is also really important, at the end of the session you don't want to see any swirls or other imperfections in the surface.

Actually the trouble with french polishing is that I have to keep reminding myself that "everything" is really important, and it is so easy to stuff up! Like you I am self-taught and have been doing it for about five years now. I am not an expert but enjoy giving it a go!

Good luck.

Swifty

[woodPixel]

Swifty - you are bang-on correct.

Your pictures are amazing. I've also done the same and have a selection of sauce and mustard bottles scabbed out of various bins on recycling night :)

I have stopped on V2. There are some pictures my son took and Ill post these tonight. It became obvious that I wasn't improving anything by continuing.... too many compounding errors!

So! Version 3 is begun this arvo....

-- The block was sanded back down.
-- I used Acqucoat ... and by zeus did that make a HUGE difference.
-- There were three coats ... mistake #1
-- Then I applied a single seal coat of shellac using the old mouse... mistake #2
-- The old mouse was worn, not really a mouse, and had a bit of mineral oil still on it...
-- So I made a new mouse using Loving Wifes daily house shirt. Its pure cotton! It cut it into rags. She was quite pleased at me.
-- The new mouse was made according to The Instructions, not my bodgy attempts at using baby wipes :)

After applying a few thin coats using the new mouse it was instantly (and I mean instantly) a massive massive MASSIVE improvement over all my previous efforts. It immediately popped. The touch was luxurious. The surface was dead flat, glassy smooth. Soooo glorious.

I took it out to the sun and I can see my O's and 8's. They seem to be "under" the last layer, so I'll need to sand it all back and go to Version 4.

I think this may be the old mouse leaving oil or something. The new mouse is free of that..... I didnt know about straightening out, so I'll need to find out what that is.

I'm starting to get the hang of it. Its GREAT for therapy. I really enjoy the punishment it hands out if one isn't absolutely exact. It absolutely whacks mistakes like a headmasters cane! swish swish!

[woodPixel]

Here is where I left Version 2.

It looked .... OK-ish. Not great, but not bad.

I had my son take photos of it. He is a rabid photographer... but I didn't guide him as to what to do. Nor did I check his work before sanding it back....

Soooooo, he took this shot using a megadollar camera, using a megadollar lens on a trendy angle and a megadollar polarising filter as (he said after) there was "too much shine and background reflection on the surface". UGH! That was the idea mate!.... So, here is the last pic I have with it as shot by Picasso himself.

NO SHINE! :doh:


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[woodPixel]

We'll I have to say that the Aquacoat is amazing. Its seriously good.

Here is the bit only with the Aquacoat...

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And here it is after the first bodying session.

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PPWWHHHOOORRRRR.... So much better. It was dead flat, shiny, clean and clear. The only hassles I had which are in outlined in the post above, which I had some odd streaking that seemed to be "under" the shellac at the right angle/light. The photo isn't showing these lines (my phones camera is a bit ordinary).

Well, I sanded it back AGAIN and I'm doing Version 4, which has had none of these issues so far (plus I'm using a Real Mouse). Have to say that V4 is even better.

It seems that burning through fast iterations after realising the errors and mistakes seems to be working for me.

Its great fun.

[woodPixel]

Running into repeated problems.

I keep getting swirls.

I've reduced the concentration, used a new mouse and sanded back twice.

The Aquacoat leaves a marvellous dead flat surface, but the material does leave a surface shine, even after a good sanding back with 400 grit.

I think I'll order some FFFF pumice and see how that goes instead.

Have to admit, this is MUCH harder to get a great result than any other finish. I can see why people use poly, nitro, CA and epoxy... ALL are SO much easier!

I shall persist 510344


edit - Luthiers save the day.... I shall put down one coat of shellac BEFORE the aquacoat to protect the timber against "the shinies" Musical Instrument Makers Love Aqua Coat! | Aqua Coat (https://www.aquacoat.com/blogs/news/musical-instrument-makers-love-aqua-coat)

[taz01]

Keep at it WP!

I'm currently going down the FP (much more suitable for unit living than other finishes) and either by fluke or some progress the panel gauge I'm working on is coming together, at least to a beginner's standard.

It's slow work but rewarding as the reflections in the work become clearer.

[homey]

Hi wP,

if the swirls you mention are in the pattern of your circles, figures of eight etc I suspect this is oil. At the end of the polishing process the oil can be removed by using a rubber which is free from oil and is very lightly charged with a little shellac but mostly meths. Moving across the surface in straight sweeps picks up the residual oil.

Oil shouldn’t be trapped between applications of shellac as each polishing session fuses the new shellac into the previous applied finish. Any oil used in the polishing process (very very little) should remain on top ready to be picked up during the spiriting off.

To me FP is just like planing or veneering - you wonder how it will ever go right, then the “Aha!” moment comes and you can’t understand what the problem was.

Keep plugging away! :~

Regards,

Brian

[woodPixel]

OK, here we go! At last a decent finish.

I've spent a lot of time reading these and other replies across the forum, plus a few guitar forums, plus the AC sites info.

French Polishing is a technique that is EVERY technique. Skimp anywhere and one is punished. It is a strict teacher.



I don't have any FFFF pumice, so Ill order a little baggie of that. I feel my attempts to "modernise" are simply creating a rod for my own back... stick to what's been done for millennia and follow the rules (a torment for a rebellious psych like mine!)


For todays experiments I did two things.

FIRST side-- a few thin coats of FP to seal the area, then a skim of Aquacoat, followed by a sand using 320grit (the HWCF cloth backed, nice!). This was followed by a good FP build layer. I feel it has worked very well.

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Keep in mind a few things - 1) the lighting is just the dining area, 2) its my old mobile taking the picture, 3) it is Merbau which is as porous as anything can get, and 4) I cannot take a decent photo :)

I can attest, however, that it is now glassy smooth and none of the irritating artefacts are being left "under" the polish.

Im finally happy enough (of course Ill look back soon enough and scoff at my amateurish hacking).


SECOND side -- is a mod on this first, which is 1) FP wash 2) AC smear, dry and sand 3) second FP with a light 320 sand 4) a second AC smear... which is being left to dry.

The reason I did the second test is the Aquacoat website and several luthier videos mentioned AC can go over pretty much anything. The idea being that the AC, by itself on wood first, will leave weird glossy patches, which is exactly what I was getting.... so they suggested prepping the timber and putting down a set of FP wash coats to seal the timber (no shinies!) then use AC to fill only the pores.... sand that lightly to remove the goobies, then FP over that. If ye has pits still, do again.

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Seems simple enough and it seems to work. The photo is nothing to look at, but it is FFLLAATT.... which is Very Nice.

I also used an applicator I trust that is used for vehicle bog. It is a lovely little tool and lays down bog and smears like no other.

Apologies for my long and probably TERRIBLY BORING post!


TO DO
-- Get some FFFF
-- Body up these sides

LESSONS
-- Don't be inventive, just follow the ancient instructions
-- 320 grit works better than 400 grit for clearing the goobs on Aquacoat
-- A wash of FP is an amazing sealer

[woodPixel]

Having some fun, but in order ways, not.

This is a deliberate shot showing how part of the timber is showing blotchiness.

The edges of the piece are very nice indeed. About 15mm in, there is an obvious transition to non-shininess.

I've tried VERY hard to ensure all areas have equal cover. I'm doing o's, O's and S's in different orientations. I even rewatched the video about to ensure I wasn't missing something.

Either way, I'm getting shiny edges and "dry" looking areas. It is very frustrating. It seems to be all in one area on the end. There is zero possibility of glue or contaminants as its been sanded back MANY times :)

Here is a photos taken to show it up at its worst. It was a bit hard to capture. The sun is deliberately at an angle to highlight it, plus I used a filter to bring it out more.

Simply put, it looks DRY.....

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I thought to sand it very lightly with 320 grit (HWFCF cloth backed) and gave it two more bodying sessions. Here is another photo showing the patches towards the front-left.

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Again the shot angle and filter is showing the worst deliberately.

Other than that, in real life, it looks GREAT!

Im making a mini-bench, so tomorrow I'll put some work into that and do all this on a much bigger piece. Perhaps the little piece is letting me creep errors in and not giving areas to dry properly between sessions.


Any advice or wisdom is welcome! :)

[Swifty]

Hi wPix,

How many sessions have you done? I find it common to see uneven surface glossiness right up until say the fifth session. That piece I showed above had ten sessions done on it, early in the edges were not as good as the middle. That's normal. As you lay more layers down, things even out.

After a few days, the polish on the above piece sank into the grain, so that the surface showed irregularities in the surface reflection that correspond to the pores in the blackwood. This is normal and just means, add more sessions. Until the shellac doesn't shrink anymore.

Don't worry about the oil, it is unlikely to be causing problems if you just use a few drops when you feel the pad starting to stick. If you use mineral oil, (paraffin oil is what I use), it doesn't stay in the polish but rises to the top and can be spirited off a the end of the job. More important is to make sure that after you have done your circles and eights, that you straighten out by rubbing parallel to the grain, until all the swirls are invisible when you look along the grain at that low angle where you can see imperfections. If the swirls are still there, keep straightening with increasing pressure until they are gone. This is where the oil lubricant is most important, coz the rubber is most likely to stick, jump, stutter or cause other problems under the pressure.

If you don't get rid of the swirls from each session, they will get buried during the next session and you will never be able to get them out.

Regards
Swifty

[homey]

wP,

Difficult to tell from your pics but that whitish blush at one end may be moisture. This can happen even as a result of humidity, i.e. no contaminants in the polish. It's well-documented (here's just one link: Controlling Shellac Blush (https://www.woodweb.com/knowledge_base/Controlling_Shellac_Blush.html))
so you should be able to find it easily with a DDG search. I have a humidity meter in the workshop; if I need to FP when it's really humid I run a dehumidifier for an hour beforehand.

As Swifty has mentioned, the oil should not be a problem if you use a little. On boxes I put literally one drop of oil on my finger tip then brush it across the rubber. The oil gets removed at the spiriting off stage.

Swifty also mentions the sinking of shellac. I can testify to this. I first came across it FPing in Andrew Crawford's workshop. Has a beautiful finish down then he warned me it would sink overnight. It most certainly did, but further polishing fixed the issue.

Best regards,

Brian

[woodPixel]

OK, I found my problem - I'm actually burning through in places :)

Too much meths.


https://youtu.be/GVIFGshnlwI

[surfdabbler]

Just came across this thread. I'm glad I've inspired to you work on this. :) Keep it up. I think you have the right idea to work and practice on a test piece. I'll have to try the AquaCoat, or some other proper grain filling next time I do it. My surface had been previously polished, so some shellac was probably left in the surface, helping to fill the grain. I don't know how you do it without oil. When I get rid of the oil, that's when everything stops working. Anyway, I'm looking forward to my next FP job. It's certainly addictive.

[woodPixel]

It is addictive.

I fear that swmbo was a tad peeved at me with the myriad of bottles and accoutrements accumulated....it now lives in a box 😃😃

I'm yet to order some pumice.

My problem so far has been over polishing and burning through the work at the polishing stage. I think my mouse is a bit too scruffy.

The build stage happens quickly enough. I also need to work on the filling stage...and use more test pieces, not just one or two.

Perhaps I need 10 samples on the go all the time 😀😀

[surfdabbler]

My problem so far has been over polishing and burning through the work at the polishing stage. I think my mouse is a bit too scruffy.

Yes, that's where I have the most problems. As soon as the oil is gone, I can't do much without burning through. Put some oil back on, and then I find it much easier to work. I'm leaving the oil on, just a super fine film, and then the final polish with scratch-X with a bit of oil mixed in. Once it's polished, the final buff removes the polish and any remaining oil. That worked well for me in the end.

I also found the switch to high quality cotton sheet was better than tshirt material. The t-shirt seems to load up with more polish for higher build at the early stages, but was really grabbing at the final polishing stages, where the cotton sheet glides on the surface better, with less pressure. Still have to be careful not to burn through though.