Announcement

Collapse
No announcement yet.

What timber finishing technique do you use / prefer?

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • What timber finishing technique do you use / prefer?

    I was wondering what sort of timber finishes you guys/gals use, particularly on speakers of course, but not limited to.

    I generally just head for a non-yellowing water based polyurethane (multiple coats sanded in between) but its not really giving me what I want.

    The project I'm working on at the moment is going to have side panels made from solid Jarrah and I want to achieve:
    - nice rich color like what appears when you wet the timber
    - really smooth finish (I have clear grain filler)
    - durable high gloss finish (polished like glass)

    Basically looking to achieve this sort of finish (example image, not my speaker):
    Click image for larger version

Name:	3254fecb5b9b067630372ab25491f144.jpg
Views:	271
Size:	145.3 KB
ID:	1468043


    The poly doesn't really help bring out the color of the wood. In my experience, after sanding and apply the clear it looks sort of dull, or not as rich as just wetting the timber.

    I was thinking that maybe a coat of a very light stain (like a sort of light rose color) would help bring out the natural color of the wood first and then poly but was curious as to what others might be doing?

  • #2
    I've had good luck with paste wax applied with 0000 steel wool over stain, but I don't think it would look like your picture. Some use it over poly with nice results, that might get you closer...

    Some examples: https://www.youtube.com/results?sear...and+steel+wool

    You are probably looking for something like a piano black finish.

    Comment


    • #3
      Sprayed on Lacquer is forgiving for a top coat. Lacquer can be layered and polished without creating witness lines. To add depth I like BLO on the raw wood and sealed with Seal Coat. Whatever you do make a bunch of test panels and document your steps.
      John H

      Synergy Horn, SLS-85, BMR-3L, Mini-TL, BR-2, Titan OB, B452, Udique, Vultus, Latus1, Seriatim, Aperivox,Pencil Tower

      Comment


      • #4
        I use tung oil almost exclusively, for its ease of application. Depending on how many coats you apply the result can vary from satin that just brings out the grain to full on gloss. You can even rub it out for a piano finish like in the picture above. This is tung on my solid rosewood electric bass:

        Click image for larger version

Name:	Bass cropped.jpg
Views:	233
Size:	66.1 KB
ID:	1468053
        www.billfitzmaurice.com
        www.billfitzmaurice.info/forum

        Comment


        • Geoff Millar
          Geoff Millar commented
          Editing a comment
          That bass looks fantastic, I can imagine the late great John Entwistle playing it in his skeleton suit!

          Geoff

        • blue934
          blue934 commented
          Editing a comment
          That's just stunning, Bill! Great work.

      • #5
        Poly doesn't bring out color? Are you using water-based or oil based? Oil based Poly pops grain exactly the same as BLO because most use BLO as a base. Water based is just garbo and really should only be used if you are trying to keep light colored woods as light as possible.

        The best finish hands down is sprayed 2K lacquer (aka auto clear coat). Its the dominant professional finish nowadays, but really isn't something you should be doing DIY, its nasty stuff.

        If you need more than just basic protection (anything veneered does), it pretty much comes down to varnish vs lacquer (nitro) vs shellac. You wouldn't do a flat waxed oil finish on anything but solid wood furniture (or little stuff like turnings). Epoxy is done too, but that's usually when you want an ultra thick film coat.

        Varnish is the easiest to apply (rag it on), number of coats just depends on how thinned it is (real danish oils are just super thin varnish, not sure there is any actual varnish in Watco) and how much film you want. Varnish is the most durable DIY finish, but it takes a long time to dry and even longer to cure (must be cured to rub out to polish). But its also the hardest to repair well.

        Lacquer requires spray equipment, and a little more skill to apply (not much more though). But it dries and cures quite quickly. Its not quite as durable as varnish but its very easy to fix, since the coats all melt together; you can take any lacquered piece, clean it well, maybe go over it with some 400(+) grit lightly, then spray on a new coat and viola, brand new finish.

        Shellac is the hardest to apply well (it dries so fast that there is a bit of a learning curve, also if you are adjusting the cut). Its sort of between lacquer and varnish, the hardest diy finish, but scratches easier than varnish. Shellac will toughen up softer woods better than the other finishes, but its brittle (it can flake or chip off when super old). Dewaxed shellac is also the universal finish, every finish will stick to it, so its used between finishes. But its not used as a primary finish much, its just not as good overall as varnish or lacquer.

        The greatest american woodworker (Sam Maloof) used thinned varnishes (a diy danish oil) on his pieces, that's what I use on more artistic pieces. Oil and wax alone is epic on pieces you touch, but it offers no real protection, its for looks and feel (for example you would use it on your throne, should you build yourself one from wood).

        For veneered pieces I'd stick to either varnish or lacquer. Both will look similar (lacquer is slightly less yellow at first, but will eventually become more yellow as it yellows with age, think decades though). Both can be polished to a gloss. Lacquer is much quicker to do and is much easier to fix (or refresh at some point in the future). Varnish is pretty much foolproof (as long as you let it dry enough always) and will hold up the best looking new over time.

        Stains are something noobs use (pigment stains are akin to thinned paint). Inverted grain makes it obvious stains were used. Just buy the wood you are trying to fake with the stain. I use dyes when I need to correct color inconsistencies (walnut sapwood for example) or when refinishing old furniture and need color adjustments.
        Last edited by Waldo; 04-06-2021, 03:23 PM.

        Comment


        • #6
          Originally posted by billfitzmaurice View Post
          I use tung oil almost exclusively, for its ease of application. Depending on how many coats you apply the result can vary from satin that just brings out the grain to full on gloss. You can even rub it out for a piano finish like in the picture above. This is tung on my solid rosewood electric bass:

          Click image for larger version

Name:	Bass cropped.jpg
Views:	233
Size:	66.1 KB
ID:	1468053
          That bass is epic, well done.

          You mean Formby's? If so, its actually just a varnish, I believe a Phenolic varnish like Waterlox.

          Tung oil itself is lighter in color and slower to dry than BLO, doesn't dry to a film. Though a solid wood bass (especially if its your personal one) would be a great application for an oil and wax finish since its something you touch.

          Comment


          • #7
            Yes, that's Formby's, and it's not a pure tung oil. What matters to me is that it wipes on easily, self-levels, and I can apply at least six coats per day if I want to. It's also a breeze to fix if it gets scratched, just take it back to dull with Scotchbrite pads and put on a few more coats. It also has no problems adhering to oily hardwoods. I tried using water base poly over rosewood, and it flaked off.
            www.billfitzmaurice.com
            www.billfitzmaurice.info/forum

            Comment


            • #8
              Originally posted by DeZZar View Post
              I was wondering what sort of timber finishes you guys/gals use, particularly on speakers of course, but not limited to.

              I generally just head for a non-yellowing water based polyurethane (multiple coats sanded in between) but its not really giving me what I want.

              The project I'm working on at the moment is going to have side panels made from solid Jarrah and I want to achieve:
              - nice rich color like what appears when you wet the timber
              - really smooth finish (I have clear grain filler)
              - durable high gloss finish (polished like glass)

              Basically looking to achieve this sort of finish (example image, not my speaker):
              Click image for larger version  Name:	3254fecb5b9b067630372ab25491f144.jpg Views:	85 Size:	145.3 KB ID:	1468043


              The poly doesn't really help bring out the color of the wood. In my experience, after sanding and apply the clear it looks sort of dull, or not as rich as just wetting the timber.

              I was thinking that maybe a coat of a very light stain (like a sort of light rose color) would help bring out the natural color of the wood first and then poly but was curious as to what others might be doing?
              For this type of finish I would use whatever stains/dyes that you want to use to augment the grain, then spray a catalyzed Automotive urethane clear, or have an auto body shop do it if you're not equipped to do so yourself. The stuff is as durable as any finish available, and can be cut, buffed & polished to a mirror finish. I've used it on speaker cabinets before and it works beautifully. I've also used Minwax spray can urethane with very good results, but it's not as durable as a catalyzed urethane.

              That speaker pic you posted is not likely just a clear over the wood. It looks like dyes were used just like I did with the speaker below. Put on a dark dye, sand it back so it's only in the grain, then apply a lighter color. The result is a grain that absolutely pops, then you bury it in clear.

              This is minwax spray can urethane:


              Comment


              • #9
                Thanks for all the advice.

                I think the reason I went water based poly originally was because yellowing was a bit of a concern. From what I understand the oil poly is pretty much guaranteed to yellow if not yellow straight from the tin. However, the water poly doesn't give any richness of color where the oil does....catch 22?

                The catalyzed stuff would be the go in terms of shine and durability but I wonder if it suffers the same problem of not bringing out the color?

                Can we get a durable high gloss finish over an enriched timber color that wont go yellow if the sun shines through your living room window in the morning?

                Comment


                • #10
                  The oil is the yellow. Poly doesn't get more yellow over time like lacquer does. But oil is yellow. The yellowing of lacquer takes decades.

                  Comment


                  • #11
                    Originally posted by DeZZar View Post
                    Thanks for all the advice.

                    Can we get a durable high gloss finish over an enriched timber color that wont go yellow if the sun shines through your living room window in the morning?
                    Lacquer and other automotive and spar/ outdoor polyurethanes are UV stable, but the wood underneath is not. My new subwoofer picked up a ring from a lamp base after the sun baked it a few days. This was a wood problem and not the lacquer finish.
                    John H

                    Synergy Horn, SLS-85, BMR-3L, Mini-TL, BR-2, Titan OB, B452, Udique, Vultus, Latus1, Seriatim, Aperivox,Pencil Tower

                    Comment


                    • #12
                      I agree with jhollander - lacquer or an automotive finish are two things that would give you the high gloss finish you are looking for. Another product to add to the list is a conversion varnish; it slots right in between lacquer and automotive finish. The reason these finishes would be superior for this purpose is because they are relatively hard finishes which allows them to be easily cut and polished.

                      Polyurethanes, despite popular opinion, are not good for buffing and polishing. Sure, they can be polished to some degree, but the inherent design of polyurethane - being, different length mers mixed together in one product as opposed to a more uniform structure provided in two part lacquers, conversion varnish, and automotive clear coats - imbues the product with an intentional degree of softness and pliability, which is where poly gets a reputation for me being “strong”. In actuality, it is tough due to its malleability, but is not hard like glass (which is very strong, but less tough). But because they are tougher, this incorrectly translates to stronger, which defaults to better, which isn’t really the case in most situations. Add to that the fact that most box store polys are not catalyzed products, it often takes months for it to cure.

                      Oils are a terrible protective topcoat for wood (I’m not talking about oil based poly and the such, but linseed oil and the such); in fact, they are not protective at all except to lend some moisture resistance. Instead, applying multiple layers of oil just saturates the wood with oil. This does give it a nice wet or semi wet look, but offers zero bump and abrasion resistance. The smoothness achieved by polishing oil finishes is actually from polishing the wood fibers in the presence of a lubricant. The lubricant allows for a finer polish and carries away the sheared off fibers just like wet sanding a car. I don’t recommend them for anything but butcher blocks and traditional furniture or instruments. An oil finish needs to be top coated with something, but you often need to wait weeks for it to dry else it will spoil or compromise the topcoat.

                      A sprayed, catalyzed finish will give you the clearest, strongest, most polish-able surface. It will always be clearer then a poly for the simple reason that most catalyzed finishes (conversion varnish is the odd child here) will burn in to the layer below it, making each successively layer a part of the previous layer. Poly only adheres to the layer below it by mechanical adhesion which is why you must scuff sand between coats. Scuff sanding lacquer isn’t technically necessary; it just polishes the old layer to make a smoother overall finish. And this is one of those cases where more isn’t always better. 3 strong coats is all you need. Once your dried film thickness exceeds the recommended amount, you are more likely to have the finish crack. Put too much wet product on at once, and it acts like a stripper from all the solvents, taking off previous layers and even stain.

                      As far as making the wood pop, jim85 had some good suggestions. Hi lighting and low lighting lumber makes the grain pop for sure. I often used a small amount of analine dye in dewaxed shellac as a seal coat, then lightly sand before top coating. Oil based poly and such do give you a little more warmth - read: yellow tone - but that’s from the different refractory characteristics of the oil based resin. And that warmth can easily be achieved with a few drops of dye in the aftermentioned method.

                      Comment


                      • #13
                        Thanks again for the advice.

                        I see you guys in the states can buy 2 Pac in a can which is cool. Unfortunately don't seem to able to get the same thing down under.

                        There's an auto body repair shop just up the street so I might go have a chat to them about clear coat!

                        In the meantime I'll run some experiments on scrap to see what brings out the best in the wood.

                        Comment


                        • #14
                          Amazon has 2K in a can, at least in the states.
                          "Everything is nothing without a high sound quality." (Sure Electronics)

                          Comment


                          • #15
                            Just be aware 2K lacquer is orders of magnitude more dangerous for your health when applying than regular lacquer or varnish. You absolutely have to be in a spray booth or outside with a respirator, goggles, and no exposed skin.

                            Very few hobby woodworkers will touch the stuff despite it being a superior finish.

                            Comment


                            • DeZZar
                              DeZZar commented
                              Editing a comment
                              Yeah agree...that's why I would get a shop to do it instead.
                          Working...
                          X