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  • lacquer for a finish? durable?

    just wanted to get your collective input on my next project.
    I'm about to start finishing a walnut computer desk/hutch that I've been working on. I also recently purchased an HVLP system. I've always brushed on poly for my previous projects but I'm contemplating lacquer. from what I've read and researched it sprays on easier, dries faster, doesn't need sanding between coats, but that it's less durable.

    I've also read that it's easier to repair, so if it does get banged up I can fix it. Once the poly starts to chip/peel I don't think there's much chance of repair.

    any of you guys have much experience with lacquer long term?

  • #2
    Re: lacquer for a finish? durable?

    This won't be much help most likely because I personally don't know the process that our spray guys go through, but we use a lacquer finish on our game tables (pottergametables.com). I do know that they add some kind of hardner. One of my specifications was that the table tops be able to take lots of punishment. When you get 7 or 8 guys together playing poker, you need a durable top. Plus, since our tables have a dining top, this also needs to be tough. I'll ask and see if I can get more information from them. I probably should know this already, but I've always been too afraid of messing up a table to do it myself.

    Rick Potter

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    • #3
      Re: lacquer for a finish? durable?

      To answer the main question: Lacquer is not as durable and less moisture resistant than the wood finish "Polyurethane" (which is actually an oxidizing varnish with urethane additives rather than a true chemically catalyzed polyurethane).
      Lacquer dries by evaporation: The solvent evaporates leaving a solid film. If you put solvent on it, it goes back into solution. Shellac is the same type of coating but not as hard a finish.
      Advantages: Easy to spray, requiring lower pressure. Can be "repaired" easier as it can be put back into solution. Rubs out easier for a high gloss finish. Dries quickly. In essence: Quick, easy and inexpensive. Less "yellowing" or amber tint associated with the varnishes.
      Disadvantages: Not as hard or tough, so it is more easily damaged. Not as moisture resistant (think "sweat rings" from a glass of cold tea or a cold bottle of beer). The solvent is more flammable than that usually used with varnish. Less thickness per coat, so requires more coats to achieve same build. More prone to "blushing" when spraying in cold weather or high humidity. (Blushing is a milky look that is caused by water vapor trapped in the coating. It is caused when the rapid evaporation of the solvents as it leaves the spray gun lowers the ambient air to below the dew point for the relative humidity. This can be controlled with a slower drying thinner or blush retarder additive which is normally xylene).

      Varnish (including the "polyurethane" wood finishes) dry to "tack free by evaporation, but cure by oxidation. Lacquer thinner will cause it to bubble /crack and peel if applied over the top of it.
      Advantages: Tough durable coating that is moisture resistant (altho not as moisture resistant as the long-oil spar varnishes). Less flammable to spray as the solvent is usually turpentine or mineral spirits (higher flashpoint than lacquer thinner which contains methyl-ethyl-ketone and methyl-isobutyl-ketones).
      Disadvantages: Longer drying times (can take up to a week or more to really harden and a week or more longer to fully cure) Requires more air pressure and works better with a larger spray orifice. Hard to repair (even partially cured runs and drips). Due to the longer dry time, the overspray remains sticky longer. More prone to oxidation/deterioration from direct sunlight. Will add an amber or yellow cast which will darken as it ages.

      If you have store-bought furniture in your house, odds are some or all of it is a lacquer finish. It holds up well indoor, and can be waxed or oiled to preserve it. It does not do well on table tops, bar tops, or severe wear areas. However, it can be used as a sealer coat with poly/varnish applied over the surfaces subject to the severe wear/moisture.

      If you have an HVLP, please invest in a good respirator rated for OV (organic vapors), eye protection (the blood vessels in your eyes will absorb 10 times the toxins that your skin will), and don't spray around any ignition source like a pilot light, gas heater, cigarette lighter, etc.

      I didn't go into the water-based (vinyl) coatings, which most home owner/hobbyist HVLP rigs won't spray due the large orifice and large air volume required to atomize them. Water molecules are much larger than most coating solvents, and do not atomize easily.

      Lacquer, enamel, varnish, oil, shellac, epoxies, vinyl, wax, latex, stains, tints, polyurethanes, etc all have advantages and disadvantages. And each have different blends to boot, and some can be used in combination. None is the perfect do-all coating, so it depends on what the item is used for and the look you want.


      Sorry this is long. Hope some of it helps. If you spit out your drink laughing at some of the posts you read, and kick the legs of the desk in response, I would go with poly, at least for the desk top surface and boot areas. Just a couple coats of shellac or lacquer can give you all the beautiful natural look of the wood, but will require a little bit more maintenance to keep it that way.

      Go
      Practicing at practical wood working

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      • #4
        Re: lacquer for a finish? durable?

        There are some water-borne products that spray like lacquer, but dry to a more durable surface. One I use is Resisthane from Highland Hardware, mainly because it's cheaper than some others.

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        • #5
          Re: lacquer for a finish? durable?

          Thanks for the explanation, Gofor. That's a lot of really good information, and I'll probably end up printing it and posting it in the shop.

          jbateman, I've heard of the resisthane before, and been curious about it. In the past, when doing bartops or outdoor finishes, I've used Spar Varathane. It's a brush-on, but it is really tough stuff. Does anyone know how does Resisthane compare to that?
          I put it all back together better than before. There\'s lots of leftover parts.

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          • #6
            Re: lacquer for a finish? durable?

            there are catalyzed lacquers that will hold up well, that are used on most kitchen cabinets,
            non catalyzed lacquers are not a real resistant finish to moisture, but Lacquers are the main Industrial finish.

            the main reason to use lacquers is speed, you can spray and many times it is dust free in less than 10 Min's and re coat in 30 Min's, so one can spray out a project in less than a few hrs,

            but for toughness like said polyurethane is tough as nails, more difficult to fix tho, but if you want a finish resistance to most any thing polyurethane is probly your best choice, there can be problems in applying the finish, with bubbling and sometimes the flow of the materials but you can have that with all finishes, but poly seems to have a few more than some, also if you plan on multi coats there are window of time so the finish will properly bond to it self, so read and follow the directions of the manufacture. (the problem with repair is that the finish does not melt with solvents and thus new finish will not blend in with the old and become one, so one will need to in a sense refinish or re-coat the side or face that is damage, not a spot fix),
            Push sticks/blocks Save Fingers
            ~~~~~~~~~~~~~~~~~~~
            "The true measure of a man is how he treats someone who can do him absolutely no good."
            attributed to Samuel Johnson
            ~~~~~~~~~~~~~~~~~~~
            PUBLIC NOTICE: Due to recent budget cuts, the rising cost of electricity, gas, and oil...plus the current state of the economy............the light at the end of the tunnel, has been turned off.

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            • #7
              Re: lacquer for a finish? durable?

              thanks for all the good info. I know for a fact our kitchen table is lacquer, and it shows some wear but it's not terrible as long as we are good with it. my bro-in-law works at a professional cabinet shop and they spray poly on everything because it's so durable. but I've heard when you spray poly it stays in the air and lands wet on everything and once it dries it's a pain to clean up. I don't have a separate area to spray my finish so I'll have to be good about covering up everything in the shop.

              I do have a good respirator/eye protection etc.

              I really like the way the lacquer looks, I may try to spray lacquer on everything else and use poly for the table top. I still haven't decided. I have one piece of furniture I refinished about 10 years ago, and the poly on top has started to chip. I really don't have a good way of repairing it. while the lacquer isn't as durable, I can repair it. plus I like the quick application and not having to sand between coats.

              so maybe less durable, but not a total waste of time, durable enough?

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              • #8
                Re: lacquer for a finish? durable?

                The idea of just doing the table top with poly is a good idea--just make sure the two sheens match. I have use all of the above mentioned and by far the polyurathane is the most durable by a long run. The spar varnish is a little over the top and I don't really think the table top would get enough abuse to warrant its use. As far as not having to sand between coats of lacquer that only holds true if you are doing continuous spraying and the undercoats have not fully cured. I have found that a very light sanding and an over-zelous job with a proper tack-rag you will get a much better finish. If your avatar is a sample of your work I think you will make the right decision.

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                • #9
                  Re: lacquer for a finish? durable?

                  Originally posted by rprice54 View Post
                  thanks for all the good info. I know for a fact our kitchen table is lacquer, and it shows some wear but it's not terrible as long as we are good with it. my bro-in-law works at a professional cabinet shop and they spray poly on everything because it's so durable. but I've heard when you spray poly it stays in the air and lands wet on everything and once it dries it's a pain to clean up. I don't have a separate area to spray my finish so I'll have to be good about covering up everything in the shop.

                  I do have a good respirator/eye protection etc.

                  I really like the way the lacquer looks, I may try to spray lacquer on everything else and use poly for the table top. I still haven't decided. I have one piece of furniture I refinished about 10 years ago, and the poly on top has started to chip. I really don't have a good way of repairing it. while the lacquer isn't as durable, I can repair it. plus I like the quick application and not having to sand between coats.

                  so maybe less durable, but not a total waste of time, durable enough?
                  If you use the poly only on the top, put some on a test scrap and compare it to the lacquer part. The light amber of the poly may be a good compliment and may look terrible. Please test it first.
                  I haven't used the pre-cat lacquer, so can't comment on it as to ease of repair.
                  You are correct about the poly overspray. It also is a mess walking around in it, as your feet stick to the floor or plastic tarp, and it will build up on the bottom of your shoes. You may want to take them off before going into the house!!. However, also realize that the lacquer overspray, altho much dries before it settles, is extremely flammable. This is partially because each little dried particle exposes a lot of surface area to the oxygen in the air. It will burn very readily. Covering everything is a good idea, and then blowing off all reusable tarps with the outlet from your shop vac/air hose, or hosing them down after you are done to get the "dust" off is also a good idea.

                  Sounds like you have a good idea of your options, and also know how to repair the lacquer if needed. You also know how you and yours take care of your belongings, so that also is a factor. Many fine tables and desks survived from the 1800's with only oil and/or wax as a finish, and hand-rubbed shellac has been used as for the "French Polish" look for centuries. Pick what is best for you. Using walnut, even if circumstances happen that cause the finish to be damaged, you will have the option to refinish with something different in the future if you feel you have to, so the work in building it won't be lost. In other words, other than pouring acrylic over it, I doubt any choice you make will be a bad one. As you have said, a more durable coating may last longer, but you will eventually pay for it if you have to refinish it. If you go with the lacquer and aren't happy, you can use a wipe-on poly in place with the windows open to refinish it at a later date (preferably in a warm season .

                  Go
                  Last edited by Gofor; 12-03-2007, 09:55 PM.
                  Practicing at practical wood working

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                  • #10
                    Re: lacquer for a finish? durable?

                    thanks for the info.

                    I have a sample drying right now, I sprayed lacquer on one side and wiped some satin poly on the other. We'll see how the sheens compare.

                    I guess I could always slap some shellac on there and cover it with poly if the lacquer isn't tough enough.

                    BTW: it's not me I'm worried about abusing the desk. It's my 3 year old and 1 year old and their metal toy cars that scares me. I'll just tell people we're going for the distressed look.

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                    • #11
                      Re: lacquer for a finish? durable?

                      If you choose to spray lacquer, do in a well ventilated area, and NO open flame or pilots, (hot water, furnace or other), to not run motors that are open that may spark. (shop vacuum), (warning probly goes for all solvent based sprays). but lacquer is or can be very dangerous in this area,

                      I would cover your saw with a drop cloth, and any other major surface that you to protect, yes mostly it will be dry by the time it settles but it can leave a dust and some may stick, most over spray will jsut sweep up,
                      Push sticks/blocks Save Fingers
                      ~~~~~~~~~~~~~~~~~~~
                      "The true measure of a man is how he treats someone who can do him absolutely no good."
                      attributed to Samuel Johnson
                      ~~~~~~~~~~~~~~~~~~~
                      PUBLIC NOTICE: Due to recent budget cuts, the rising cost of electricity, gas, and oil...plus the current state of the economy............the light at the end of the tunnel, has been turned off.

                      Comment


                      • #12
                        Re: lacquer for a finish? durable?

                        for now, while the basement is unfinished, I will use the adjacent area for spraying, so my shop will be closed off. I will be blowing the fumes out with a box fan in the window. The only thing on will be the HVLP and the lights. Thanks for the tips everyone.

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                        • #13
                          Re: lacquer for a finish? durable?

                          I would put the fan blowing into the area from the shop side. That way you are not pulling flammable fumes over a non-explosion proof electric motor on their way out the window.

                          Any spraying I do at home is limited to when I can do it outside under a temporary canopy I bought. Not worth the risk to me to do it in any structure attached to my home.

                          Go
                          Practicing at practical wood working

                          Comment


                          • #14
                            Re: lacquer for a finish? durable?

                            As "gofor" says be careful with fan motors etc---it is not advisable to pull the exhaust (fumes) directly into the path of the motor---as all motors that are not "explosive proof" will most likely have arcing on start-up at the internal switch or where the brushes make contact with the armature-----believe it or not this can lead to some serious consequences if the fume/air ratio reaches an explosive point.

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                            • #15
                              Re: lacquer for a finish? durable?

                              we're having an usual burst of warmer weather this weekend and next week- in the 70's, I'll be spraying outside. thanks for the tips. no need to blow up the house...

                              One woodworker, who I respect, has recommded deft lacquer. he buys the brushing lacquer and thins it a bit for spraying. he says the main difference is retarders are added to the brushing lacquer to provide a little more working time so you can brush it, otherwise the same finish in the end when it dries.

                              any thoughts from you guys? I haven't been able to find pure lacquer for spraying around here, and with the warm weather coming up, I don't think I have time to order any online.

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