- 3 April 2020 at 2:07 am #655544Marc-Andre PetitParticipant
I’m trying to finish a small pine box with french polishing to practice the technique. The surface finish is filled with small ripples (ridges) in the direction of the grain. I’ve try to sand them down but when start back the process they come back. Any idea what that is? Is it what you get for not filling the grain ? Is the layer too thin?
I’ve polished in circle, figure of eight and finish with the grain.
I’ve tried the same thing on a piece of poplar and I get the same thing.
Any idea ? thank you!
You must be logged in to access attached files.3 April 2020 at 8:13 pm #655631Sven-Olof JanssonParticipant
As usual I might be woefully wrong, but the photos seem to show grain-raising. Some authors claim that this only occurs with water based finishes, while others state that any liquid (including oils) will raise the grain if applied to a bare surface.
One suggested solution is to wet the surfaces, allow them to dry, and then sand with a 320 grit (P400 – P600). My own approach has been to use 0000 steel wool after having applied the first layer, which has worked well enough with water based finishes.
There are a number of methods for smoothing surfaces after being done with the finish, but I wonder if they are applicable to the situation of raised grain. Sadly. it might be that you need to use sand paper, pumice or steel wool to take the raising down, in which case the beautiful polishing probably will be lost.
Hopefully, there will be other comments recommending less draconian measures.
London, UK; Boston, MA
You must be logged in to access attached files.4 April 2020 at 3:14 am #655663kary karahadianParticipant
Also consider the material you are using for the outside of the pad. Fine linen is often used. I’ve switched to the microfibre cloth we all use to clean our eyeglass lenses. Inside of the pad is wool.
With french polishing, less is always better than more for each session.
kary4 April 2020 at 1:58 pm #655709Marc-Andre PetitParticipant
I’ve sanded down until the surface become flat again and start the process over and it help tremendously. But this time i used only circle motion. The finish is building up fine and the ripples are, for the most, gone.
I doubt that my rubber is the problem (linen cloth stuffed with liberon cotton fiber). It is a combination of bad preparation and bad technique.
Thanks to both of you, i’ll keep rubbing and sort that down!
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