Replies

1. 
   Ray | Jan 24, 2011 11:57pm | #1

   That type of filler is usually applied before staining, pumice should absorb stain well.   My grandfather used to swear by plaster of paris as a filler.  I tried it on oak before staining and it really does a great job.

2. 
   cwalvoord | Jan 25, 2011 09:15am | #2

   Ray,

   That makes sense although the article in FWW does not mention staining after rubbing in the pummice with a dillute shellac.  Last night I tried to rub a thinned coat of Watco on the box in hopes that it would indeed darken the white pumice in the pores.  Apparently the shellac had already sealed it up because neither the pumice nor the surrounding wood darkened at all.  I ended up just sanding it off and putting on the stringing and banding.  I am still not sure how I will finish the box.  I would like to fill the pores and try a French polish but I will have to do a bit more research as to the best way to accomplish that.

   Chris

3. 
   hammer1 | Jan 25, 2011 10:33am | #3

   I have no idea what the FWW article says. You don't use the pumice as a pore filler alone in traditional French polishing. It's used very sparingly along with shellac and plenty of elbow grease. Here is a pretty good tutorial on French polishing, it may answer some of your questions.

   http://www.milburnguitars.com/frenchpolish.html

4. 
   HowardAcheson | Jan 25, 2011 01:22pm | #4

   I know this going to sound like a wise-*ss answer but your story is a perfect example of why the experienced finishers here alway recommend first working with scrap material from you project.  This is even more important if you are attempting a finish process new to you.  French Polishing is a technique that required learning and practice.  But any time you use a new finish or type of finish you should test it.  With the ever increasing amount of reformulation of finishes due to VOC regulations it is important to test almost all finishes before committing them to your project. 

   You certainly don't want your project to be your learning curve when it's so easy to avoid it.  Professional and experianced finishers will test their finishing schedule almost any time they start the process.

1. 
   cwalvoord | Jan 25, 2011 01:58pm | #5

   Thanks Howie and I agree with you that it is always important to test out the entire finish schedule on a sample.  That is what this box is - just a sample/test/learning experience. 

   I have successfully used a wide variety of finishes from simple rub on "Danish oils" to dyes, stains, and glazes.  I have sprayed water based clear coats and rubbed them out.  I have brushed, padded and sprayed shellac before to add color, to seal between layers, and to provide the final protection.  When I read the article in FWW about French polishing I thought I would give it a try.  My first attempt at the pore filling step did not work so well so I just sanded the whole thing down and will try again.  Just thought I would see if anyone here has any suggestions for things I might be doing wrong.

   Chris

1. 
   DonStephan | Jan 25, 2011 08:54pm | #6

   In an accompanying photo of the article it looked like the pumice was used sparingly, as mentioned above.  Not sure the intent was to fill pores with pumice, but to have the pumice act like very fine abrasive and fill the pores mainly with sawdust.

   On finer grain woods one could use shellac as a pore filler, but my understanding is that shellac continues to shrink over the coming months.  So if shellac used to fill larger pores, may be sufficient shrink over time to highlight the pore structure.  No experience french polishing anything but cherry.

5. 
   roc | Jan 26, 2011 01:51am | #7

   Article was interesting but limited

   I recommend George Frank's old article here on FWW or in old issue of the mag.

   https://www.finewoodworking.com/ToolGuide/ToolGuidePDF.aspx?id=2144

   Lately I been farting around with French polishing.  I have practiced on scrap and am now "practicing" on my big table.  Here are some thoughts and observations:

   The shellac simply refuses to span and fill a small pore.  It goes concave in the middle and builds up around the pore/flaw/what ever.  I can take a syringe and drop a drop in a tiny concave anomaly and it will pull to the perimeter of the flaw over and over.  Evil stuff.

   I kind of think but have no actual experience with this :

   The pumice, used sparingly, may give the shellac a "structure" to span the minute pores and so build and fill.   I have a full new can of 4F sitting in my tool crib and have not experimented with it.  This table I am working on is not a "Fine" showroom/museum piece and I just know I should not lavish that kind of work on an every day dining table.  Still.  I am learning from my work meaning:

   • What happens if I don't sand.

   • How much can I fill without filler (some over time/many many coats). Quite a bit actually.  Looking across the surface I seen no pores with the last bigbody forae.  Sources say they will come back as shellac tightens over time.

   • How to fix stuff, already had several scratches and a small dent from daily use.  Fixed them no prob.

   • Can a person plane off a flaw with a #1 plane and add finish until it totally disappears ?  Yep.

   • What role do scrapers play?  Do I have to sand after scraping?  I have developed an appreciation for them.

   • What pattern is best ? Ws and Os, just straight strokes length wise, just straight cross then lengthwise, tight swirls etc.

   • How strong can I go with bodying up?  Quite strong.  Adding alc before shellac seems to be over rated and unnecessary for bodying up.

   • What cloth and filling is best?  Old cotton hankie is good, T-shirt very bad, cotton balls bad for filling, cheese cloth bad but usable, wool cut right off a hunk of lambs wool leather is totally the best so far. old rag wool sock may be good but have yet to try that.

   • DO NOT ! NOT! NOT ! let a little hole wear in the cover and keep going.  Leaves a line in the finish like it has a hair under the finish for the length of the stroke, in my case I was going across the table with straight strokes.  Has been hell to get rid of those.  I finally wound up leaving them and swirl bodied above them.

   Wheyue ! That was close.

   Actual experience with the rubber is deviating some from the many articles I have read.  Some contradict each other.  Many say to rub hard as rubber dries out.  Some say to lightly rub only.  In actual practice I find with the rubber loaded with a relatively strong mix of shellac rubbing hard as the rubber dries out, which all agree is the time to press hard, causes surface damage even with some mineral oil on the surface and on the rubber.

   It seems the time to rub hard is when using a rubber that is mostly denatured alcohol and nearly dry.  I bodied up a bunch again today and am about to the point I can just go with alcohol and spirit it off and smooth and polish it.

   Again, talking out my fanny here, haven't used the pumice but can see where it would work, I think the pumice will go clear (I read that) , like window glass, with a significant layer of shellac over it.  Any clumps are to be sanded off.  If you think about it even with the minute wood dust mixed in with the 4F the 4F is still there.

   More to follow.

   PS: I took a photo to showing off my big Starrett straight edge to an acquaintance so am posting it here.

   
1. 
   cwalvoord | Jan 26, 2011 10:58am | #8

   Roc,

   Thanks for the link and for the long reply.  There are lots of good suggestions in there and plenty of bits for me to think about.  It sounds like you have been doing a lot of experimenting and learning.  I have to do some more of both.  I may give the pumice another try and see if I can get it to fill the pores and not remain white.  I think the first time I may have used too much pumice and not rubbed enough.  I also did not top coat it as I was afraid it would have been too hard to sand off.

   Chris

1. 
   roc | Jan 29, 2011 11:30pm | #9

   Latest experience

   Yesterday I just added alcohol to the pad I been using to "body up" (build up many layers of finish ).  The pad has a lot of cheese cloth rolled up with cotton hankie over that.  The results left on the table was not as smooth as I hoped so I added a layer of wool cut right off a leather lamb's skin.  That really worked well.

   An interesting thing happened though.  The idea with "spiriting off" is to use up the rest of the shellac that is in the pad and to use the alcohol to redesolve and "stretch" the shellac that is already on the table.  Some how though even if I added the alcohol to the interior of the wad in the pad the shellac would tend to travel up into the cotton cover twisted above the pad rather than down into the wool layer.  I wound up adding so much alcohol to the outside of the cotton cover in an attempt to wash the shellac down into the wool bottom layer that I left some minor lines of finish in the surface.

   Lesson learned.  Would be best not to mix the material in the inner pad.  Tomorrow I will make up a new pad with just wool for the inside and cotton hankie for the cover.

   I am about out of the special Hock alcohol that has supposedly had the water removed.  I have read the solvent just pulls water out of the air when you open it.  I have a can of basic basic denatured from the Ace Hardware.  I just use it to clean stuff.

   Like I keep saying this is no first rate finish.

   My question is since I need to get more denatured what does everyone think of :

    BEHLEN BEKHOL SOLVENT - A high quality solvent especially formulated by Behlen to dissolve shellac flakes.  Evaporates slower than traditional denatured alcohol.

   #1011 - $8.95 - QUART CANS

   From Homestead Finishing verses the low water Hock verses the cheep Ace stuff ?

   As I understand it I can't get the Hock stuff now.

   PS: the pores are back just barely.

6. 
   cwalvoord | Jan 30, 2011 12:10pm | #10

   So yesterday I started over on this little project following the detailed instructions discussed here: http://www.millburnguitars.com/frenchpolish.html.  I began with freshly scraped and sanded surfaces and carefully filled in all the defects in my shop-made inlay banding.  Then applied three spit coats of shellac and let it dry for a few hours.  Made a rubber with a coarse covering (cloth from Homestead finishing) and old wool sock innards.  I applied alcohol to the core, dabbed the rubber in a sprinkle of pumice and cleared it with alcohol and then rubbed in circles. I worked for about ten minutes on an area approximately 2" x 4" and got no appreciable filling of the pores.  There was enough shellac on wood that it was definitely sealed but there was no film build on the surface.  I tried both pressing pretty hard and only lightly.  

   Any thoughts on what I am doing wrong?  I am about ready to resort to some traditional paste pore filler and move on.

   Thanks, Chris

      

1. 
   roc | Jan 30, 2011 04:44pm | #13

   Nerd with calculator

   Do you know in the cartoons when the nerd with the calculator has to throw a baseball or do some other feat that he is wholly unsuited for but has to do it and so calculates wind speed and probabilities and all that other stuff and winds up succeeding because he read a book once about it.

   Well my comments probably won't have the same out come but I can dream.  With calculator in hand and tape on my glasses here goes:

   Try putting the pumice in a dry "bag" like your rubber.  No innards.  Like a tobacco bag

   Tap the bag on the surface while surface is dry.

   add some shellac to your rubber inside the innards

   take the strokes across the surface perpendicular to the grain

   let the surface set up for a half hour or even less

   repeat many many times (not a whole lot of rubbing but do add pumice bag and shellac pad cycle often)

   I probably didn't put the decimal place in the right place in the 32nd frame but who knows maybe the nerd CAN win the big game.

   :   )

1. 
   cwalvoord | Jan 30, 2011 04:02pm | #11

   Roc, Thanks for the

   Roc,

   Thanks for the suggestion and all the other thoughts you have volunteered.  it is always helpful to hear about others' learning process.  BTW, have you seen a difference between your "special" alcohol and the generic stuff?  I have been using a big can of Sunnyside brand that came from one borg or another but I am wondering if some of the 99% pure stuff would work better, however better may be defined.

   Chris

1. 
   roc | Jan 30, 2011 04:42pm | #12

   Land Mines On The Learning Journey

    >BTW, have you seen a difference between your "special" alcohol and the generic stuff?< 

   Yes; about $10 difference in the price.

   :   )

   Heck I am afeared to use the cheep stuff on the table.  All manner of bad stuff might happen.  Nah I don't really know there.  Seems like I read the good stuff dries faster and in some cases the cheep stuff can get cloudy in the finish.

   I just had the cheep stuff around to clean the tape deck heads and my brushes etc.

   It might contradict some things I have said but often I like to start with the good stuff (so I bought the Hock) and then when I get good results start backing off on the quality until I start to see problems.  That way I am not introducing too many land mines on my learning journey.

1. 
   xmike | Jan 31, 2011 05:33pm | #14

   Regarding which alcohol to use, I recently read an article that pointed out that wood alcohol (a poison) is much cheaper than grain alcohol (good for you).  Therefore, wood alcohol is taking up more and more of the mix in denatured alcohol than in the even recent past - so much so, it was claimed, that you are in danger of wood alcohol poisoning from the fumes when you work with it in inclosed places - such as my basement workshop with no windows to speak of.

   So, I changed to pure grain alcohol.  I noticed no difference in my finish, but my family noticed that I no longer emerged from my workshop after working with shellac looking like the wrath of God - i.e., flushed red skin, slight redning of the eyes. 

   So I looked up the symptoms of mild wood alcohol poisoning - flushed (red) skin, redning of the eyes, blindness, liver failure.  Perhaps the $10 a quart is worth it?  Hardly a scientifically valid experiment, but I'm now convinced.

2. 
   roc | Jan 31, 2011 08:57pm | #16

   Thanks for the heads up Mike

   I have read some guys go to the local liquer store and just buy Everclear. 

   http://en.wikipedia.org/wiki/Everclear_alcohol

   http://www.chacha.com/question/what-states-is-the-liquor-everclear-legal

3. 
   SteveSchoene | Jan 31, 2011 10:44pm | #17

   Interesting enough, an antedote for methanol poisoning is ethanol, so the combination would be less dangerous than methanol itself.  But, the problem is that methanol dries faster than ethanol making shellac mixed with methanol harder to apply. The Sunnyside brand has a relatively high percent of ethanol. 

   Everclear would be your only source of pure grain alcohol.  But be sure to get the 190 proof variety.  The 151 proof would be much more available, but contains more water than would be desirable.  But quite a few states ban the 190 proof.  Besides, in addition to the contents you also have to pay the sin tax on alcohol.  . 

7. 
   cwalvoord | Jan 31, 2011 05:46pm | #15

   Mike,

   Where do you get your pure grain alcohol?

   Chris