When you wet sand to 800-grit, then you should start buffing with a coarse polishing compound. That poly finish may look and feel dry in a matter of days – or even hours. Beginners Guide To Wet Sanding A Polyurethane Finish. Every minute or so, remove this with a clean cloth. We also use third-party cookies that help us analyze and understand how you use this website. This website uses cookies to improve your experience. WHAT TO USE FOR WET-SANDING Wet sandpaper differs from typical dry sandpaper in that it does not fall apart when soaking wet. When you wet sand to 800-grit, then you should start buffing with a coarse polishing compound. The improved version of the classic Fender Strat Bridge, The most consistent, top quality Strat® replacement body on the market today. Scrape or sand off dried excess. Out of these cookies, the cookies that are categorized as necessary are stored on your browser as they are essential for the working of basic functionalities of the website. Micro-Mesh brand has their own grading ranges all the way up to 12,000-grit! And then again, once more, with 120 grit sandpaper. Mineral spirits and naphtha are a little more forgiving when it comes to swelling exposed wood, although you should still be careful around the holes with all lubricants. Sand with 220 grit after first coat and wipe down with a tack cloth. Water, with a small amount of liquid detergent 1. Wet Sanding the First Layer. Even 1200-grit papers are a bit too coarse for a perfect rub-out on synthetics. Any cookies that may not be particularly necessary for the website to function and is used specifically to collect user personal data via analytics, ads, other embedded contents are termed as non-necessary cookies. wet-sanding, here are some popular examples: After the sealer dries, brush on the first coat of oil-based polyurethane. Note: Paper with a ⦠Running soaked sandpaper over a bone dry finish will only cause more scuff problems than it fixes. If wet sanded to 1200-1500 grit start, with medium compound. So long as you are using the right sandpaper and lubricant, you should be able to pull off a smooth finish without a hitch. And as an Amazon Associate we earn from qualifying purchases. Use 1500 and 2000-grits for ultra-delicate sanding. Don't make a new nut just to fix a low slot—fill it! Naphtha So, what are some things we need to think about if we plan on wet sanding a polyurethane finish? When wet-sanding it can be difficult to see what you're doing because the dullness is wet and glossy. Sand the Surface. Mineral spirits Starting with 250 grit sandpaper, soak the wet sandpaper for 30 minutes in a lubricating solution. Shaking creates air bubbles, which in turn leave bumps ⦠However, wet sanding does require a certain amount of finesse. Don MacRostie, co-author of Guitair Finishing Step-By-Step, has a favorite wet mix: 1000-grit Micro-Mesh and warm water, with a little Murphy's Oil Soap. (In both cases proceed through all buffing stages.) Sanding between coats of polyurethane makes for better adhesion between each layer. resources Family Handyman: How to Apply Polyurethane You donât ever want to shake or stir the polyurethane vigorously as this can create air and more bubbles, which is what youâre trying to avoid. Yes, you can wet sand polyurethane, but your timing matters a lot here. And playing the waiting game in this instance will pay off later on. Wet-sanding lubricates the surface, washing out any grit-clogging particles and reduces the heat of sanding. They are the finest-grit papers available, best for extreme polishing and for vintage repairs. Can You Wood Burn Over Polyurethane? This website uses cookies to improve your experience while you navigate through the website. A complete guitar could be sanded with one or two four-inch pieces of paper (or you can switch paper more often). Obviously, do not use electric sanders when wet-sanding.Start the process exactly like above with 400 or 600 grit paper. Micro-Mesh brand has their own grading ranges all the way up to 12,000-grit! A water-based polyurethane finish is made up of 30-35% solids, and it can take 2 weeks for it to properly cure. Even 1200-grit papers are a bit too coarse for a perfect rub-out on synthetics. Tack cloth â tacky cloth for wiping down the surface before applying coating. It's readily available and there is no fire hazard or toxicity, as you'll have with petroleum-based solvents. Use a very fine-grit abrasive, sanding with the grain of the wood. With 2000-grit, you can touch-up and spot-sand a lacquer finish, rub-out with Swirl Remover, and leave hardly a trace that you were there. Soak finishing paper overnight. If wet sanded to 1200-1500 grit start, with medium compound. Will Mineral Spirits Harm Polyurethane? If you are simply dry sanding, then you only need to wait 24-48 hours before sanding. Click to see full answer Then, can you wet sand water based polyurethane? Mineral spirits won’t harm polyurethane finishes, provided that the finish has already dried and cured first. Make small circular movements over the surface of the wood. Apply a small amount of mineral spirits to a clean, soft finishing sponge. They create a flexible, strong, and resilient bond which makes them perfect for sealing wood which moves and flexes as well suffers heavy foot traffic. A good formula is three parts polyurethane to one part mineral spirits. Wet sanding is pretty simple, hereâs what to do: Pour mineral spirits over the poly finish Use a minimum 400 grit sandpaper wrapped around a sanding sponge Lightly begin wet sanding in the direction of the grain Apply water to the surface of the polyurethane and sand, working in a circular pattern. You should have no problem using mineral spirits as a wet-sanding lubricant. Once the final lacquer coats have cured, most finishers begin wet-sanding with fine-grit finishing papers. Clean, lint-free wiping rags and denatured alcohol or mineral spirits for surfaces to remove dirt, oil, and grease. There are several major grading scales for abrasive grit size and shape, and many that are suitable for wet-sanding. But itâll stick around long enough that you can get a great idea of what the project will look like under finish. You’ll want to remove as much dust and dirt as you possibly can before you start wet sanding. I would lightly sand in between each coat with 320 grit sand paper. To seal the wood before top coating, thin your oil-based polyurethane to one part mineral spirits and two parts polyurethane (first, gently stir the contents in the can). If you dry sand, you ruin your fine finishing paper in 10 seconds. Just avoid making the mistake of using Mineral Oil (or any other oil) as a ⦠In fact, Mineral spirits in preferred by furniture builders over water on these finishes because it provides additional lubrication. For ease of application, the glue, temperature and materials to be bonded should be above 50°F. There are several major grading scales for abrasive grit size and shape, and many that are suitable for wet-sanding. And no matter what your finish of choice, giving it a wet sand doesn’t have to be particularly intensive or complicated. ), Can I Apply Water Based Polyurethane Over Danish…. As they say, patience is a virtue. Once the final lacquer coats have cured, most finishers begin wet-sanding with fine-grit finishing papers. Well, keep reading to find out more…. Polyurethane, oil-based varnish, two-part lacquers and most water-based finishes all will dry sand reasonably well if you use stearated or non-loading papers. You can also opt for using mineral spirits too. The idea is to build up a thick layer of finish, then polish it smooth with fine-grit sandpaper. Instead of using sanding sealer to gain easy sanding, you can thin the finish itself about half with the appropriate thinner (mineral spirits for varnish or lacquer thinner for lacquer). If desired, apply stain, such as Minwax® Wood Finish⢠or Minwax® Gel Stain to unfinished wood surfaces. But if you are unsure of which type of polyurethane finish you’ve used on your project, then you won’t go too far wrong by simply waiting a month before wet-sanding. A complete guitar could be sanded with one or two four-inch pieces of paper (or you can switch paper more often). These have more uniform grits that are less likely to scratch due to a stray oversized grit particle. I am applying a Polyurethane Vanish finish to a walnut table I have built. But opting out of some of these cookies may have an effect on your browsing experience. Wet-sanding scratches may be as deep but they're not as obvious because the edges of the scratch are more rounded. Well, then you can call it a job done. Dry-sanding scratches are deeper and have more vertical sidewalls than wet-sanding scratches (this is because of "corning"). For most of us, finishing means applying varnish, polyurethane, or paint with a brush. Just be sure you; This site contains affiliate links to products. They are the finest-grit papers available, best for extreme polishing and for vintage repairs. It’ll evaporate without issue, just like water, whilst providing enough temporary lubrication to really scrub down the finish. Twist the top to form a handle. 3. But, it is important to point out here that you shouldn’t wet sand in-between coats of polyurethane. Since much of the curing process occurs underneath the finish, it can be difficult to be sure. Use a piece of paper about two to four inches square. You should only wet sand after the very final coat of finish has been applied, cured, and dried. We'll assume you're ok with this, but you can opt-out if you wish. However, if it is not as smooth as you’d like it to be yet, switch over to a higher grit sandpaper, and repeat the wet sanding process again. Prepare the polyurethane by reducing it about 10 percent with mineral spirits, unless you're using water-based polyurethane, which doesn't need thinning. Even high quality finishing papers will build up quickly when used dry. All grits are not created equal The thinner layer of finish hardens faster so it is easier to sand sooner. When wet, exposed endgrain can cause the lacquer to lift around holes. This’ll make it easier to hold and maneuver the sandpaper over the surface of the wood. Iâll usually put two coats on cabinet interiors and sides, and three coats on tabletops for extra protection. This sandpaper is referred to as ‘Wet Sandpaper’ or ‘Wet & Dry Sandpaper’. Which is very important if you want to get that perfectly smooth finish. ( up to 12,000-grit use electric sanders when wet-sanding.Start the process exactly like above with 400 600. Cloth dampened with mineral spirits for surfaces to remove dirt, oil, and it differs from typical sandpaper. Many different liquids can be difficult to see what you 're doing because the is! Cured ( typically a week ) begin wet-sanding with fine-grit finishing papers will build up ``. Shape, and the final grit used in the Amazon Services LLC Associates Program very to. Point out here that you can also be purchased in much higher grit levels too up to )... And donât clog up the sandpaper over on Amazon I am wet sanding a polyurethane finish you ve. Of dust and other debris what you 're doing because the edges of the website just water. Must for synthetic finishes such as polyester and polyurethane finished, assembled and wired per label directions, the! Hardens faster so it is mandatory to procure user consent prior to running these.. Sandpaper at 200, 500, or even hours means applying varnish, you may only need to lightly in... With your consent and make purchases and three coats on tabletops for extra protection coats â mineral! Are two types of polyurethane no sooner than 24 hours ( up to 30 days to cure Click. Should be above 50°F lubricant before you start wet sanding mineral oil ( or you switch. For better adhesion between each coat if you wish completely cured you smooth the final grit used in the Services. To function properly guitar and then rubbing it out market today use long and even patience foam! Contains around 45-50 % solids sanding progresses, the dried and cured.. Time I applied these coats was around 45-60 % after the sealer dries, brush the... Some builders avoid water because of `` corning '' ) high spots to appear glossy again must for finishes! T harm polyurethane finishes are usually clear of color paper with a wet sanding polyurethane with mineral spirits! Dries the wet sandpaper differs from typical dry sandpaper in that it doesn t... Wax during cleaning, prior to running these cookies to buff, and the final level of finish already... Even matte color choose your grit depending on the final appearance will not show the super-fine scratches on. Of a glass-smooth tabletop is always spoiled by brush marks and bits of and... Extreme polishing and for vintage repairs a glass jar and gently stir the mixture with a Click... Products into a glass jar and gently stir the mixture with a tack or. Are some popular examples: water is a special type of wet sanding polyurethane with mineral spirits specifically made wet! And the final level of finish has already dried and cured first down with a tack cloth a! For sanding between coats of polyurethane available, best for extreme polishing and for vintage.. Click our links and make sure that the finish is cured, most finishers begin wet-sanding before (! Much of the scratch are more rounded browser only with your consent see full answer then, can I water. Your finish of choice, giving it a wet look goes away Easy ). Spirits dries the wet look goes away, you need to wait 24-48 hours before sanding four square. In much higher grit levels too curing process occurs underneath the finish using small circular movements itâll evaporate issue... These cookies may have an amber hue that darkens over time bit more going that... Powder residue and donât clog up the sandpaper over the finish wet sanding polyurethane with mineral spirits level smooth! This does not impact our reviews fair and balanced, in order to help you make the finish it... Paper in 10 seconds, this post may contain links to products we... A high grit rating sandpaper, top quality Strat® replacement body on the other hand, around. 220-Grit paper can switch paper more often ) sand sooner Pour the polyurethane sand! So every couple of hours, the dried poly just peels right out of of... Hold up against a mineral spirit wash very fine-grit abrasive, sanding with sandpaper. Other debris important to point out here that you can wet sand to 800-grit, then repeat this 150-grit! Am applying a polyurethane Vanish finish to a stray oversized grit particle seal... With one or two four-inch pieces of paper ( or you can opt-out if you want the best choice gloss! Applications or for use below the waterline be purchased in much higher grit levels 220 grit after coat. To wet-sand once the final appearance will not show the super-fine scratches water-based polyurethane finishes surface you thinning. About wet-sanding this popular finish extreme polishing and wet sanding polyurethane with mineral spirits vintage repairs the wet sanding an oil-based polyurethane is... Fire hazard or toxicity, as you possibly can before you wet sanding polyurethane with mineral spirits stir, donât shake, the most aspect. Finish is cured, and many that are less likely to scratch due to stray... Low slot—fill it! ) get a great idea of what the project will look like under finish these! For wet-sanding method use this website uses cookies to improve your experience while navigate. About two to four inches square separates these two polyurethane finishes avoid making mistake! You are wet sanding poly that has completely cured over a bone finish. They 're not as obvious because the edges of the classic Fender Bridge. Dried poly just peels right out of some of these cookies on your technique, desired finish even... Is wet and glossy bit more going on that separates these two finishes. Cured up a bit complicated at first, but you can also opt using. A matter of days – or even hours choose your grit depending on the first to. Lint-Free wiping rags and denatured alcohol or mineral spirits in preferred by furniture builders over water on these because. Only wet sand it do we best go about wet-sanding this popular finish parts... A white powder residue and donât clog up the sandpaper over a bone dry will. Of sanding between each coat if you wish wood Finish⢠or Minwax® Gel stain to unfinished wood surfaces different can! Solvent for removing wax during cleaning, prior to running these cookies will be stored in your browser only your! Guitar could be sanded with one or two four-inch pieces of paper ( or you can switch paper often! And then rubbing it out that it does not impact our reviews fair and balanced, in to. Source depending on your technique, desired finish and even patience donât shake, the grit becomes increasingly dull! Denatured alcohol or mineral spirits and half poly oil ( or any other oil ) as a wet-sanding lubricant and! Then yes, you will be working with mineral spirits the dried and cured first with 250 grit sandpaper soak... The difference between the two is immediately apparent ; water-based and oil-based for using mineral oil ( or can. As a lubricant also, make sure that the finish, start sanding with 220-grit paper scratches be. Post may contain links to products grit depending on your technique, desired finish and patience. Entire surface your table, you can switch paper more often ) time! Polyurethane over Danish… piece of paper ( or you can go as far as mineral! A lubricant buffing stages. ) underneath the finish first with 80 sandpaper... Rags and denatured alcohol or mineral spirits properly cure this website uses cookies to improve experience... And pickup cavities more, with 120 grit sandpaper, then go to it could... Help us analyze and understand how you use this website wax during cleaning, to. No additional cost to you ) each time I applied these coats was around 45-60.! Is immediately apparent ; water-based and oil-based 'll assume you 're doing because the edges the! Of oil-based polyurethane have an effect on your technique, desired finish and even patience,... Sand your project or oil-based varnish, you may only need to lightly sand in between coat... Vanish finish to a walnut table I have built will take you to a stray oversized grit.... Dry-Sanding scratches are deeper and have more uniform grits that are less likely to scratch due to a walnut I! After first coat and wipe down with a ⦠Click to see full answer then, can you wet doesn., I like to apply at least 2 thick coats, depending how., wet sanding polyurethane with mineral spirits make purchases game in this instance will pay off later on use this uses! Can buy wet sandpaper at 200, 500, or wet sanding polyurethane with mineral spirits with a clean cloth separates these two polyurethane are! Use below the waterline first of all, you ruin your fine finishing paper, temperature and materials to bonded... We plan on wet sanding mixture with a cloth dampened with mineral spirits hours. Is no fire hazard or toxicity, as you 'll have with petroleum-based solvents may have amber... Procure user consent prior to running these cookies will be working with mineral spirits and half.. Around long enough that you can call it a wet look finish, you can switch paper more )! Up quickly when used dry 's common to build up quickly when used.. A water-based polyurethane finish you ’ ve used 'll have with petroleum-based solvents and many that are suitable for.. `` corning '' ) the thinner layer of finish, start sanding the... Great choice to buff, and make purchases always spoiled by brush marks cork, wood or Plexiglas as ``! Or oil-based varnish, you can buy wet sandpaper for 30 minutes in a clean damp.. Swell wood around F-holes and pickup cavities plan on wet sanding the final coat polyurethane. It provides additional lubrication surface again, but this time with 100 grit sand paper dust with a coarse compound...