Page 1 of 2 12 LastLast
Results 1 to 15 of 24

Thread: I hate sanding between finish coats

  1. #1

    I hate sanding between finish coats

    I typically sand with 400 grit between finish coats but it is a long, boring process that I hate. (My favorite finish these days is minwax wipe-on poly diluted with a little mineral spirits and with a dash of tung oil added.) Does anyone have a magic finish recipe that provides a satin (NOT glossy) finish that doesn't require the hours of sanding? Should I try using an HVLP spray? I've been doing this for 30 years but surely there is some new finishing technology that provides a perfectly smooth finish sanding free.

    Sanding the Greene and Greene crib I'm making takes hours between coats

  2. #2
    My experience is that it's necessary to sand after the sanding sealer to get a smooth coat of the final finish. Alternately, wait until you put your first final coat on, then sand and shoot one more coat.

    I use water borne finishes so the water raises the grain, which means I have to sand somewhere in the schedule.

    Mike

    [I spray my finishes.]
    Last edited by Mike Henderson; 09-05-2013 at 11:19 PM.
    Go into the world and do well. But more importantly, go into the world and do good.

  3. #3
    You'll have to sand the first coat, otherwise what it feels like after that will be what you get in the end.

    With polyurethane you are forced to sand, it is this sanding that the next coat will bond to.

    If you are spraying lacquers, pre cat or post cat lacquers you can eliminate the rest of the sanding as long as you are spraying within the window. With lacquer you can respray anytime, it melts into itself. With a precat lacquer you can spray another coat hours later without sanding. With a post cat lacquer you have to be pretty quick, and it depends on the product also. If you respray between 1 and 2 hours of drying you won't need to sand.

    All the manufacturers insist you scuff between all coats.

  4. #4
    It sounds like you should investigate some different finishes. Hours of scuff sanding or de-nibbing is tough to quantify because you could be talking about a commercial bar, entire kitchen, or a jewelry box.

    If your brushing your finish a lot of sanding is inevitable as each coat is far from flat to begin with. You could switch to a self sealing waterbourbe laquer and be out in two coats with a 320 scuff in between. It all depends on how you work, what your desired outcome is, and your shop and equipment.

    if your happy with wipe on poly of all things there are dozens of easier options out there.

  5. #5
    Join Date
    Nov 2010
    Location
    Anchorage, Alaska
    Posts
    1,617
    A well-tuned hand scraper works well for quuickly de-nibbing while leaving a beautifyl dust-free finish between coats. You do have to learn to take a fine cut however.
    One can never have too many planes and chisels... or so I'm learning!!

  6. #6
    Join Date
    Jun 2008
    Location
    So Cal
    Posts
    3,786
    Some of my best work have almost as much time finishing as building.I really don't care for trying to finish everything at the end and try to build the finish as I go along.
    I good to keep the same energy thru the whole piece really pays off in the end.

  7. #7
    Join Date
    Mar 2008
    Location
    New Hampshire
    Posts
    168
    I really like General Finishes gel urethane, which I foam brush on, and then wipe off with a rag. Pretty close to perfect, if you hate sanding.

  8. #8
    Join Date
    Feb 2012
    Location
    Little Hocking, OH
    Posts
    676
    You guys are way beyond my experience level, but I really like this article. May not apply to what you are using, but does debunk the waterborne issue, in my mind anyway.

    http://www.hardwoodlumberandmore.com...The-Grain.aspx

  9. #9
    Join Date
    Jul 2013
    Location
    NE Ohio
    Posts
    1,029
    I guess I don't like sanding either but It's often a necessary step in the process of completing a piece. This is my hobby; low volume, slow pace. I might taker a different view if I were doing this for a living and sanding between coats often.

    For me, the need for sanding (or lack thereof) is a result of other choices. I choose a finish based on the look I want and the protection the piece will require. Then, I take into account my familiarity with or preference for working with certain finishes. For example, oil-based satin wipe on poly is my favorite all-around finish. For many projects, it provides a look I like, excellent general protection and it's easy to apply thin even coats. It also means I will need to sand between coats.

    For my next project I'm going do something different. I'll start with a de-waxed shellac sealcoat and then apply a water based poly. Probably the same amount of sanding but it smells better and cleans up with alcohol and water.
    -- Dan Rode

    "We are what we repeatedly do. Excellence, then, is not an act, but a habit." - Aristotle

  10. #10
    Join Date
    Apr 2012
    Location
    Great Falls, VA
    Posts
    813
    Jim, if you can get your hands on a small can of General Finishes' Arm-R-Seal Satin, I think it may be close to what you're looking for. Be sure it's the Satin finish, as it comes in Gloss and Semi-Gloss.

    I "discovered" it a couple of years ago when a clerk at a local Woodcraft suggested it and gave me a small sample bottle (doubt those are still available). Wipes on, and thin coats can be recoated within an hour or two without sanding, depending on the conditions. On smaller, turned projects, I can actually recoat within 15 mins. altho GF doesn't suggest that. Sanding with 400 grit between coats is not necessary for adhesion (as opposed to removing nibs and settled dust, which I gather by your question is not your primary concern here). That makes is pretty close to a "magic finish" for me.

    Your present mixture of thinned Minwax WOP sounds pretty good though, so not sure how much difference you'll see.

    David

  11. #11
    Join Date
    Mar 2008
    Location
    Beantown
    Posts
    2,831
    Spraying can provide a finish that's ready to go once you've invested in the equipment and have gotten past the learning curve. Of course you still need to sand between coats

    I haven't tried scuffing any type of brush on finish in....well, a long long time, so can't help you there. I can say with the pre and post cat finishes I spray scuffing is very quick. You basically just want to knock off the nibs and have a scratch pattern for the next coat to cling to. Essentially your just wiping all the parts once or twice with paper and/or sponge and back into the booth. I haven't done a crib so couldn't even ballpark, but hours sounds like maybe a bit too much scuffing? For say a typical 5 piece cabinet door it would take maybe a minute or two per door for scuffing. Again, not trying to get it perfect, just scuff off the nibs and move on, the next coat is going to cover up everything you've done anyway! The one exception would be for surfaces that need to be dead flat....like a table top. In that case it's beneficial to spend a little time getting and keeping the top flat for that last coat.

    good luck,
    JeffD

  12. #12
    Jim,

    I don't believe you need to sand between coats as much as you think you do. In fact, if you sand between every wipeon coat, you're doing yourself a disservice.

    By adding tung oil, you are actually creating an oil/varnish, which really should be wiped OFF after it's wiped on. Done this way, after many coats, you will end up with a sealed and satin surface. No build. No gloss.

    By eliminating the tung (and in fact, if you are STARTING with a wipe on poly, elminate the additional MS) you will have a strict wipe-on poly, that can be wiped on and left to dry. The trick to eliminating sanding is to make your coats thin. For the first coat, the other posters are correct: soak it in and keep soaking it in for like 10 minutes. Wipe off any pooling after that time. Next day, you have to sand it smooth. For the next N coats, don't "paint" or "lay" it on with a rag. Just get the surface slick with a finish-moistened rag. Don't work it too much. Look at it in raking light to make sure you hit all the spots. Touch up a little as needed, and then leave it alone. Every 3 coats, you can 'sand' - but only to remove dust nibs. Take your 400g sandpaper just wipe it quickly over the surface. No heavy sanding required. I've gotten blasted for saying this here before, but it shouldn't take you more than a couple minutes to 'sand' a 4x8 surface this way. Wipe off any dust. If you are wetsanding here, then let any residual water or ms evaporate for a while before putting more coats.

    Semigloss poly works extremely well in both of the above applications. I've tried Minwax and General Finishes Arm-R-Seal. Both work fine.

    Once you learn to apply it well, (dare I say, 'properly'?), you may reach the same conclusion as I: on a thin build surface, there is little difference between different starting materials regardless of varnish species, brand, or sheen.
    Last edited by Prashun Patel; 09-06-2013 at 10:48 AM.

  13. #13
    Join Date
    Sep 2006
    Location
    Deep South
    Posts
    3,970
    I used to use Minwax Wipe On Polyurethane almost exclusively and I never had to sand to the extent you apparently are. Just a light quick once-over with 320 or 400 grit is all it took to eliminate the dust nibs. Any more sanding and you are just removing good finish and increasing the requirement for subsequent coats. I don't understand the reasoning behind diluting with mineral spirits and contaminating the mix with tongue oil. Maybe you know something I don't but if I want a tough polyurethane finish, then I don't want to compromise the results with any kind of oil.

  14. #14
    Join Date
    Aug 2008
    Location
    Marquette MI
    Posts
    524
    I use the same finish mixture and usually use 320 grit for the middle 2 out of 4 or 5 coats - then 400 and 600. I use Minwax Satin Poly for one third of the 3 part mixture. A very important step is careful dust removal after each sanding. I don't know of any good way around the final sanding steps for a really good finish. I use my drum sander to get the planer/jointer marks out before starting the tedious part.

  15. #15
    Join Date
    Mar 2005
    Location
    Raleigh, NC
    Posts
    888
    I'm with Art, wipe-on out of the can is what I use when I varnish. However, I almost always put on a sealer coat (Zinnser no wax), then rub it out with 0000 steel wool followed by 400 grit for a baby butt smoothness. There shouldn't be any further sanding required unless there's a lot of dust in the air.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •