Replies

1. 
   MikeHennessy | Dec 11, 2007 02:45pm | #1

   This is one of my favorite finishing techniques for many projects. I like to apply the Danish Oil (Watco) with fine sandpaper or a 3M pad. This makes a kid of slurry that will fill any pores in the wood and give it a nice, hand-rubbed look as well as bring out the grain patterns.

   It is imperative to allow this coat to dry thoroughly before applying poly. I wait at least 3 days, and as much as a week if I'm not in a hurry. Then, I very lightly sand (you can use a 3M pad again) and apply the poly. I prefer the wipe-on poly to spray cans.

   Mike Hennessy
   Pittsburgh, PA

1. 
   Doc | Dec 11, 2007 03:31pm | #2

   Thanks so much for the reply.  I would ordinarily prefer a brush or wipe on finish, but because these boxes are so small I thought it would be easier to spray.  Either way, can I use water based polyurethane, or does it have to be oil based.  And thanks again for the help.

   Also, what grit of sandpaper for doing the slurry?

1. 
   MikeHennessy | Dec 11, 2007 05:23pm | #3

   320 or finer.

   Mike HennessyPittsburgh, PA

2. 
   saschafer | Dec 11, 2007 05:54pm | #4

   You can use water-based polyurethane over the oil, but the oil must be absolutely, positively dry. If in doubt, a thin isolation/sealant coat of shellac between the two will prevent any problems.

   -Steve

    

   Edited 12/11/2007 9:55 am ET by saschafer

1. 
   Doc | Dec 12, 2007 04:58am | #5

   Thanks for all the help.  One last question.  If I use Shellac between the Danish Oil and Polyurethane, how long should the Danish Oil dry before applying the Shellac.  As always, thanks again.

1. 
   saschafer | Dec 12, 2007 05:11am | #6

   I would wait at least three days before applying shellac over oil. In principle, you shouldn't have to wait that long, but better safe than sorry.

   -Steve

    

2. 
   Doc | Dec 12, 2007 02:20pm | #7

   Should I use any fine sandpaper or steel wool after the Danish oil and before the Shellac, and also after the Shellac and before the polyurethane?  This should be my last question, as I think I've run out.  Thanks again.

3. 
   saschafer | Dec 12, 2007 04:43pm | #9

   I typically give the surfaces a once-over with 320 or 400 grit sandpaper, primarily to remove any dust nibs. Is it necessary? Probably not at all between the oil and the shellac, possibly yes between the shellac and the polyurethane, which wants something to grab on to.

   -Steve

    

4. 
   saschafer | Dec 16, 2007 02:25am | #11

   It occurs to me that I neglected to mention something that I should have: If you're going to use shellac as a sealer/barrier coat under polyurethane, it must be dewaxed shellac. I use Zinsser SealCoat, since the manufacturer guarantees it to work under polyurethane.

   -Steve

    

5. 
   Telemike | Dec 18, 2007 06:08am | #25

   If you intend to use a water based finish later on, shellac or not, don't use real steel wool. Tiny fragments broken off in the wood will rust in the water. The dissolved iron will react with tannins in the wood to form speckles ranging from ugly grey in light woods to a deep rich ebony in dark woods. Except the ebony color is scattered around in specks and splotches. Use fine sand paper or synthetic steel wool.

6. 
   Doc | Dec 18, 2007 06:29am | #26

   I know absolutely nothing about finishing, and I seem to be consistenly one bad decision ahead of each piece of advice.  I thought spray shellac would eliminate brush strokes, but I ended up with a mottled texture.  It seems that this is a consequence of canned shellac.  I just came from steel wooling the boxes and read your posting.  I did re-coat with shellac after using the steel wool, so maybe I'm okay to go ahead with the polyurethane.  Or should I just leave the shellac and call it good?  I'd like to finish with a paste wax (Johnsons), but I don't like the gasoline smell that it has.  Any final tips?

7. 
   Telemike | Dec 18, 2007 07:02am | #27

   Final tip: Like several others have suggested, steel wool after the danish oil is dry, then use wipe on poly. (Solvent based). My favorite finish (minwax clear) even though I'm lucky enough to enjoy asthma. Just minimize exposure to the fumes and keep whatever you finish warm until cured. Keeping freshly finished work warm goes for all the common consumer finishes.

8. 
   [email protected] | Dec 16, 2007 07:46am | #12

   Doc, you might want to consider just stopping with shellac over the Danish Oil. 

9. 
   Doc | Dec 16, 2007 04:59pm | #13

   I've done three coats of shellac right now.  I was going to start the water based polyurethane today.  These piggy banks are small, about the size of half a loaf of bread.  I'm guessing my nieces will be handling them lots, so I was thinking a more durable finish would be better.  What are your reasons why I should stop with Shellac and not continue with Polyurethane?  Finishing is baffling to me, so I'm open to all and any suggestions.  Thanks.

10. 
    saschafer | Dec 16, 2007 07:12pm | #14

    Shellac is actually pretty durable. Where polyurethane wins is in impact and abrasion resistance, because it's a softer, more resilient material.

    -Steve

     

11. 
    [email protected] | Dec 16, 2007 07:36pm | #15

    Shellac is quite durable on its own, but you have to be carefull as you add coats that you actually build up the surface.  It remains alcohol soluble, so every time you put another coat on, you can wipe off the previous one if you aren't carefull.  You can build film thickness quickly if you mix your own, to a three or two pound cut, most of the premixed stuff is about a 1-lb cut, (iirc).  But, shellac dries quickly, and requires very little wait between coats. So, you can do several coats in a day.  The quick drying means that you don't get many dust specs in it, and if you do the ease of repair makes them quick to fix. 

    Shellac is easier to repair in the future if need be.  If the poly finish gets dinged, you are pretty much faced with just sanding the whole finish off and starting over if you want it to look good.  Shellac you can just retouch the area concerned.  The new finish will just disolve the edges of the old, and the two melt into one surface. 

    And, Shellac is the most kid safe finish available.  It is used to coat M&Ms, other candies, and pills.   So, if a youngster knaws on it, the finish won't hurt them. 

    Hopefully Frenchy will chime in, and gvie you more reasons to use shellac and a few tips on it's use. 

12. 
    saschafer | Dec 16, 2007 07:41pm | #16

    "It is used to coat M&Ms..."

    That is apparently not true, or at least no longer true. Shellac is used on some other candies, like Junior Mints and Reese's Pieces.

    -Steve

     

13. 
    [email protected] | Dec 16, 2007 08:48pm | #17

    I won't argue the point, but that is/was what let them melt in your mouth and not in your hands. 

14. 
    woodshaves | Dec 17, 2007 12:21am | #18

    This is another result of "going green". Since ethanol is required to dissolve the shellac, after it coats the candy airflow evaporates the ethanol. Ethanol evaporation (at a factory level) is unacceptable to some States, too much VOCs. A "water soluble" alternative is used (there are plenty of other polymers). If the factory is at one where they do not look into it (NOT California), it may be used. Wax is the other insect secretion used on foodstuff, but shellac is the only approved "resin".

15. 
    SteveSchoene | Dec 17, 2007 04:26am | #19

    The pre-mixed shellacs are 3lb. cut for Amber and Clear (bleached) both of which contain wax.  They are apparently available in 4 lb. and even 5 lb. cut but I've not seen them in stores.  Seal Coat, the only dewaxed shellac from Zinsser except for the aerosol, is sold in 2 lb. cut concentration.   

16. 
    Doc | Dec 17, 2007 06:03am | #20

    I used the spray Shellac.  It was clear, and waxless, but it seems to have a bit of a mottled texture.  Kind of an orange peel look.  It actually looks nice, but if you look at it under the light you can see the mottled texture.  I don't know if that is my application technique or if I need to use a little steel wool or sand paper.  Is that typical of shellac to have a mottled, bumpy appearance?  Should I brush on instead to prevent that?  Do you usually use steel wool after the final coat, or only between coats?  I've never sprayed shellac before.  In my past experience with brushing it, it didn't look like this.  I'm not sure if I should sand it down and move on to poly, or fix and leave the shellac.

17. 
    saschafer | Dec 17, 2007 06:21am | #21

    I've had the same results with the Zinsser spray shellac. It goes down reasonably well, but it dries so fast that you do tend to get some orange peel. I've found that laying down a fairly heavy, wet coat will give it a chance to flow out and reduce the orange peel, but that only works on a flat, horizontal surface.

    I think the best results are obtained by padding shellac. The coats are very thin, so it takes a bit more effort to build up a film, but what you end up with is very nearly defect free.

    -Steve

     

18. 
    SteveSchoene | Dec 17, 2007 03:20pm | #22

    As the other Steve says, it's hard to avoid some orange peel using the aerosol shellac.  But all isn't lost.  I think you'll find that a little work with some 320 or 400 grit sand paper will solve the problem without sanding it all off. 

    I never use steel wool between coats--it follows hills and valleys all too well, when what you want is to only take off the tops of the hills.  Besides I am not good at getting all the little steel shards off before the next coat goes on. 

    Sanding between coats with shellac is not needed for adhesion, only to remove defects--unlike the case with varnish where the surface does need to be roughed up a bit for the next coat to have something to grab onto.   

19. 
    Doc | Dec 17, 2007 03:28pm | #23

    I've tried the steel wool and sandpaper, and both really dull the shellac that I already have on.  It does knock down some of the orange peel, but it loses quite a bit of the sheen.  With the holidays fastly approaching, and my need to get these gifts done and wrapped, what do you recommend?

    Do I smooth the shellac and leave it, or recoat with a brush?

    Do I go on with poly as I originally intended?

    In either case, do I finish up with a little wax? (I have Johnson's wax, but I'm not a big fan of the lingering smell from it)

    Thanks again.

20. 
    KiddervilleAcres | Dec 17, 2007 04:43pm | #24

    Doc,

    How about padding on 1 or 2 more coats of shellac?  The thin coats should be just enough to get the gloss look.

    Regards,Bob @ Kidderville Acres

     

    A Woodworkers mind should be the sharpest tool in the shop!

2. 
   K1500 | Dec 12, 2007 04:39pm | #8

   Make a sample up with just poly.  My limited experience suggests that it is almost impossible to distinguish natural Watco/poly from just plain poly.

1. 
   user-83153 | Dec 13, 2007 02:38am | #10

   Your observation is true if you are using an oil base poly, he has waterborne poly though.

                   Rob

3. 
   booch | Dec 18, 2007 07:08am | #28

   I'm not sure what to say on the water based poly. There are a lot of them out there and the world seems to need us to avoid solvents but I haven't changed yet. However I find myself driving all over town to find oil based poly spray.

   I know that works. I'll shut up and read on but I'm not confident that the water based spray will evenly film over the oil you started with. If you do try the water based poly try it on a real scrap not the ones you give as gifts. Said by the guy making 25 Cribbage boards for the extended family.

   In a similar vein the oil based glazing used on window sash needs an oil based primer. Then you can use latex based paint. That is written on every can of glaze I've ever bought (and this summer that was a lot of Glazing for this old house)

   I believe it will be a concoction like most finishes. Not all brands will work. Me I'm a Watco clear wipe on guy, let it cure for 1 to 2 weeks (humidity matters) then brush or spray Varathane (Flecto brand) let cure. wet sand w 600 grit. wipe and let dry then float the last coat. Smooth beautiful and deep.

   Well I did read on and you went to shellac. That will work well under Poly oil for sure. I use shellac mixed with the fine sandings for Hardwood floor filling. It works great and can be coated within 2 hours with oil w/o difficulty.

   Good luck. Pics of the banks?

   Jack of all trades and master of none - you got a problem with that?

   
   

   ---

   Edited 12/17/2007 11:11 pm by booch

1. 
   derekcohen | Dec 18, 2007 05:00pm | #29

   I've come to this discussion late, read through it all, and am still a little puzzled what the problem is.

   Cherry is not widely used in Australia, and I have worked and finished only a few pieces. My experience, however, is just as I have read, that is, it tends to become blotchy when used directly with Danish Oil. To keep the blotchiness down to a minimum, it is important to first seal the surface with a split coat of shellac. To apply Danish Oil, I rub it on with a cloth pad. I build up a few thin coats this way, never feeling that I need to sand between coats. I will use a little 600 grit W&D (used dry) sandaper at the end to remove any nibs, and then I finish with wax.

   View Image

   Regards from Perth

   Derek