Replies

1. 
   jazzdogg | Nov 10, 2004 12:08am | #1

   Gal,

   You might want to try a sharp, well-tuned, card scraper or hand plane: they will produce shavings instead of dust. FWIW, I generally apply a wash coat (or two) of shellac that serves as a barrier and helps prevent "contamination." If you're careful, you can even apply the shellac before glue-up. There have been projects when I was sanding in an oil finish on a piece made of multiple species and the colored slurry provided a desirable tinting effect, but it's always advisable to experiment with test pieces rather than taking your chances with a completed project. 

   Good luck,

   -Jazzdogg-

   Whether you think you can, or you think you can't, you're right.

2. 
   Michmesquite | Nov 10, 2004 11:01am | #2

   I just finished a Paduak and Maple foot stool for a friend. First and last time I ever use Paduak.

   _________________________________

   Michael in San Jose

   "In all affairs it's a healthy thing now and then to hang a question mark on the things you have long taken for granted." Bertrand Russell 

1. 
   Gal11 | Nov 10, 2004 11:42am | #3

   I loved that wood, it is so beautiful, I would really like to use it again, but I guess one has to be careful when using it with light colored woods...

3. 
   Pondfish | Nov 10, 2004 03:44pm | #4

   Vacuum off the dust, don't wipe it.  Use a sharp scraper and try to avoid scraping from paduak onto maple surfaces. 

   Be ready for plenty o' trouble when you finish the wood: the Paduak color will leach into oil, oil/varnish and especially shellac.  I've had some luck brushing on finish, taking care to not brush from paduak onto maple parts.  After a few coats of oil he paduak will not bleed noticeably.

   I have the same feelings about paduak as other posters--beautiful wood, but the bleeding color makes it a bloody tough wood to finish. If you can assemble after finishing, you're in luck.  Unfortunately my projects have not permitted that.

   Cheers

   Paul

1. 
   jvs | Nov 10, 2004 04:56pm | #5

   Seconded, and another note along the same lines.  I have some highly variegated QS paduak that I was finishing with shellac, planning on a few 2# cut coats and then heavier to build to grain-fill.  The shellac pulled enough color from the wood in the first two coats that the tone and contrast noticeably evened out between bands when later coats redissolved the first ones.  Not an unattractive effect, and the natural color would likely have done the same over time, but it was still surprising.

   Neat stuff with a couple of notable eccentricities--color bleed is one, the other that I really don't care for is the "wet shaggy dog" smell, even when being worked by hand.

   /jvs

1. 
   Pondfish | Nov 10, 2004 05:15pm | #6

   Yes, I found with a 2# cut of shellac you had to keep the coats very light.  A heavy later coat was disasterous, in that (as shellac will) it dissolved the earlier coats and leached up the color into dark bands.  It didn't look good on my piece, as the bands of leached color did not align well with the grain.  I ended up stripping off all the shellac and starting over. 

   The end result of the efforts was very beautiful, but what a pain to get there.  I'll use paduak again in the future, but I'll plan around finishing to avoid problems.

   I actually like the smell of paduak.  But then, I lost much of my sense of smell in a lab accident to concentrated ammonia.  Wine no longer tastes as good as it used to, but boy it was a lifesaver when changing diapers!

1. 
   jvs | Nov 10, 2004 09:53pm | #7

   Interesting!  I don't drink, and am looking at roughly another year of diaper changes including accidents.  Sooo....   what strength ammonia do you recommend?

   Kidding, of course--sorry to hear about the accident, but at least there is a glimmer of a silver lining.

   Best,

   /jvs

1. 
   Pondfish | Nov 10, 2004 10:23pm | #8

   Take 4 kg ammonium sulfate (dry powder) and add 800 grams sodium hydroxide pellers.  Seal in a plastic container, let sit 30 minutes, then open anywhere within a foot of your face.  You'll be breathing pure ammonia gas...

   Don't do this at home!  (grin)

2. 
   JohnWW | Nov 11, 2004 01:49am | #10

   As you may know, ammonia fumes are used to color certain woods especially oak for Arts and Crafts style furniture.  The usual method is to work with concentrated ammonia solution from a blueprinting outfit, but this isn't always convenient, the concentrated solution is moderately dangerous to work with, and I would guess that traditional blueprinting is probably a dying technology in the age of computer design.

   So my question is: Do you know if it would  be reasonably practical and safe to generate ammonia using the chemical reaction you described or something similar? 

   I am aware of the risks of sodium hydroxide and concentrated ammonia, don't like either, but the fuming technique does produce a look I like.  An alternative method of producing ammonia fumes would be useful if the method was no more dangerous than storing and handling concentrated ammonia solution.

   Thanks, John W.  

3. 
   Pondfish | Nov 11, 2004 02:32am | #11

   You certainly can generate ammonia using the components I mentioned.  Sodium Hydroxide mixed with an ammonium salt will release ammonia, but it may not be the most efficient way of doing it.

   I'm aware of the practice of fuming oak with ammonia as a traditional A&C finish.  It's a hazardous way to treat wood and I would look for alternatives, some of which have been posted previously to Knots, and (I think) shown up in FWW. 

   Sorry I can't be of more help...

   Paul

4. 
   splintergroupie | Nov 10, 2004 10:54pm | #9

   I use paduak laminated against lighter woods all the time. If you finish up with a belt sander on flat surfaces, you won't have the tinting problem that you have when sanding with an orbital. If i'm doing something like a box top with a raised panel that is proud of the top frame, i sand and finish the panel before glue-up of the sides, and then carefully sand the miters afterward without touching the panel. Alternatively, if the panel is the same height as the sides of the box, i sand and finish the edges of the panel, glue up the whole shebang (i make my boxes by gluing the sides up around the panel, then cutting the top off), sand flat, and then carefully re-sand just the lighter wood, be it frame or panel, without touching the padauk.

   Paduak and maple combos were great sellers for me, so i simply couldn't not use them together. If you think those are difficult to use together, an even softer white wood like birch is a greater challenge. Using it with poplar or pine is still pretty impossible. I like poplar's greenish cast in certain laminations, but it's too soft to bother with to get the color, and if i want an accent wood for pine stuff, i chose something else.