Quick French polish question - time

[Tetsuaiga]

I've just started experimenting with french polish. My results seems okay so far but i've read some people think it needs hours and hours or sessions, but i've done smaller pieces say 30cmx40cm with just 2 or 3 sessions about 10-15 minutes each as well as seal coat and I think the finish starts to looks good at this point.

So i'm wondering is there any reason not to stop when the appearance looks how you want it to? Shellac is a softish finish so I dont imagine it gets any tougher by applying more of it.

Thanks

 

[Jacob]

I always thought the whole point of french polishing was speed (and shine of course), hence cheap. It has no other advantage, being not too durable. And it can be overdone. So yes stop as soon as you can!

PS was much more cost effective than it's predecessors (oil polishing etc) but was superceded by even cheaper - sprayed nitro-cellulose etc

 

[Tetsuaiga]

I suppose it makes sense. Thanks, I might look into spraying on shellac one day.

 

[MIGNAL]

French polish is far from cheap. In fact it's usually a very labour intensive finish, hence the move to spraying on Shellac which is much quicker.
The time taken (number of sessions) depends on the type of finish you want. If you want a high gloss, super flat finish you are going to have to put more on to achieve that. Your 3 sessions of 10-15 minutes each won't even get you anywhere near. Don't forget that the finish will sink back and harden over time, which is why some people do further sessions after a number of weeks of this hardening period. Starting to sound a little labour intensive isn't it?
There's nothing wrong with your quick method of french Polishing. It's just a less fussy approach and will lead to a more 'organic' appearance. Shellac as a resin is pretty hard. Take one of the flakes and try to scratch it. It's not that soft. It mars easily because French Polish is a very thin finish.

 

[Tetsuaiga]

Does spraying costs much more in terms of actual materials? Aside from the spray gun and air compressors, i've seen people say you lose a lot of the mixture when it leaves the gun and reaches your piece.

Do you know if it's really a very significant percentage?

 

[MIGNAL]

No idea about spraying but you can brush the stuff on. Takes a lot of practice to get good at it but the initial cost is the price of a good brush - about £20. I still have a brush in use that I bought over 15 years ago, the one in the photo. The other major advantage of brushing are that you don't need any extraction apart from an open window. You can't say that of spraying. Clean up of equipment is also zero. The difficulty in applying it is that it flashes off quickly, you simply can't apply it as you would an oil based varnish. You have to be quick but not rushed. There are extenders that you can use to lengthen the flash off time, helpful but they don't give you huge amounts of extra time. The liberon easy French Polish is just Shellac with extenders added. You do have to go through the abrasive grits to level everything though. Same with spraying but less so because it's usually put on in a more even manner. Sometimes I apply with a brush, rub it all down with 800G and then do a few glazing sessions instead of going into the finer and finer grits. I guess you could call it an hybrid technique.
I think brushing is worth serious consideration if you are making fairly small, low volume items. Huge dining room tables might prove difficult but small tables, chest of drawers should be fine. In a factory type setting spraying will win every time, just on grounds of speed and the even application.

 

[Jacob]

I think what makes french polishing "quick" is that the processes don't take long - basically just a wipe over each time, but what makes it slow is the waiting in between.
So a lot of things to polish at the same time reduces the waiting as you work around from item to item without a break, which is what made it commercially viable.

 

[Tetsuaiga]

Interesting. I have given a brush a go in the past and it worked okay, though applying with a pad did leave less streaks, but then you can do either standard or wet sanding to level. The brush I bought was called a mop and looks quite different to the one in the picture above.

Is brushing on much faster than applying with pad?

I think i'm getting a bit more familiar with my application with a pad and a little spot of mineral oil also. My application time seems to depends on how long I can get away with before it starts becoming sticky. I can manage this with adding more shellac and oil but it seems the longer you are applying gradually the more the sticky it gets and the less effective adding extra shellac and oil becomes at making stickyness go away.

I think jacob says may be right, the real time it takes is waiting between applications. Plus you also have time getting your equipment sorted before you apply which can reduce efficiency a lot if you only have one thing to polish on the go.

 

[MIGNAL]

That Brush is a flat 2" cattle or Ox hair brush.
It does sound as though your sessions aren't lasting very long. To do an area 2 ft sq I would probably spend around 10 minutes per session, perhaps 10 or 12 sessions before the glazing coats. That's considered quick in my game.
Brushing is certainly a lot quicker. I could do a coat of that area in less than 1 minute. Multiply that by 15 coats and it's still not very long. It has to be less than 1 minute. Any longer than that and you'll be dragging the brush across. You will end up with brush marks and overlaps. Providing they aren't too severe they will disappear with the rubbing down.

 

[RogerS]

I think what makes french polishing "quick" is that the processes don't take long - basically just a wipe over each time, but what makes it slow is the waiting in between.
So a lot of things to polish at the same time reduces the waiting as you work around from item to item without a break, which is what made it commercially viable.

Clearly you know little about French polishing.

 

[Jacob]

I think what makes french polishing "quick" is that the processes don't take long - basically just a wipe over each time, but what makes it slow is the waiting in between.
So a lot of things to polish at the same time reduces the waiting as you work around from item to item without a break, which is what made it commercially viable.

Clearly you know little about French polishing.

Clearly you think you do! :lol:
I did a bit (as you do when asked, whether or not you can do it :shock: ) and based it on the very excellent "Woodworker Manual of Finishing and Polishing" by Charles Cliffe, and a few other sources.
Your confusion is because on the one hand french polishing could be turned into a relatively quick production process (given enough throughput) which was a big attraction compared to oil polishing, but in the other can have a lot of time given to it to produce very spectacular finishes.

 

[bugbear]

...and based it on the very excellent "Woodworker Manual of Finishing and Polishing" by Charles Cliffe, and a few other sources.

There is a problem with book sourced info in that the writer may have wanted to put down the "official" version, or a reliable method for beginners, or a spiffing wheeze of his own.

BugBear

 

[Jacob]

...and based it on the very excellent "Woodworker Manual of Finishing and Polishing" by Charles Cliffe, and a few other sources.

There is a problem with book sourced info in that the writer may have wanted to put down the "official" version, or a reliable method for beginners, or a spiffing wheeze of his own.

BugBear

This is why you have not only to use your judgement but also try out whatever is on offer, in a disinterested way.
I see you are quoting again from the Grimsdale archive BB :lol: Well done, keep up the good work!