Yes you do. Well, keep reading to find out more…. Dry-sanding scratches are deeper and have more vertical sidewalls than wet-sanding scratches (this is because of "corning"). You want to remove the "orange peel" texture before buffing (see picture). Polyurethanes were invented in the 1930s and have found their way into many home improvement products like foams, glues, finishes, and caulks. Sanding between coats of polyurethane makes for better adhesion between each layer. Wet-sand for a while then dry it all off. Once done, run your hand over the surface. wet-sanding, here are some popular examples: Water is a great choice. Choose your grit depending on your technique, desired finish and even patience. Can You Wood Burn Over Polyurethane? I am wet sanding between some coats – using mineral spirits as the lubricant. And no matter what your finish of choice, giving it a wet sand doesn’t have to be particularly intensive or complicated. Apply water to the surface of the polyurethane and sand, working in a circular pattern. 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. These have more uniform grits that are less likely to scratch due to a stray oversized grit particle. Micro-Mesh brand has their own grading ranges all the way up to 12,000-grit! Water is a great choice. 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. There is no substitute for sanding between each coat if you want the best finish. After the sealer dries, brush on the first coat of oil-based polyurethane. Naphtha The most important aspect of wet-sanding polyurethane is making sure you are wet sanding poly that has completely cured. Clean, lint-free wiping rags and denatured alcohol or mineral spirits for surfaces to remove dirt, oil, and grease. Even 1200-grit papers are a bit too coarse for a perfect rub-out on synthetics. Note: Paper with a … It’ll evaporate without issue, just like water, whilst providing enough temporary lubrication to really scrub down the finish. Also, make sure that the surface you are sanding is wet too. But as long as the polyurethane has cured, then yes, you can wet sand it. Even high quality finishing papers will build up quickly when used dry. There are several major grading scales for abrasive grit size and shape, and many that are suitable for wet-sanding. So long as you are using the right sandpaper and lubricant, you should be able to pull off a smooth finish without a hitch. Removes any lingering dust. Make small circular movements over the surface of the wood. Not a kit, this guitar is finished, assembled and wired! Here's how.1. Therefore, wet-sanded surfaces are easier to buff, and the final appearance will not show the super-fine scratches. 2. Go over the surface again, but this time with 100 grit sand paper. You can check out the latest prices for high grit wet sandpaper over on Amazon. Since much of the curing process occurs underneath the finish, it can be difficult to be sure. So, How Long Should Polyurethane Dry Before Sanding? Stir Minwax® Fast-Drying Polyurethane before and during use to eliminate settling on the bottom of the can. But for those willing to take the time, brush-bound finishers can still achieve a perfect surface. (In both cases proceed through all buffing stages.). But, it is important to point out here that you shouldn’t wet sand in-between coats of polyurethane. Therefore, wet-sanded surfaces are easier to buff, and the final appearance will not show the super-fine scratches. What we’re getting from mineral spirits is the opportunity to give wood that wet look, temporarily. However, if you are wet sanding, then you need to make sure you’ve waited long enough for the finish to completely cure. You don’t ever want to shake or stir the polyurethane vigorously as this can create air and more bubbles, which is what you’re trying to avoid. Wet-sanding lubricates the surface, washing out any grit-clogging particles and reduces the heat of sanding. Limitations: Titebond Polyurethane Glue is not for structural applications or for use below the waterline. Wet sandpaper can also be purchased in much higher grit levels too. You can get wet sandpaper from all good hardware stores. When you sand a particular area, you will only need to run over it a couple of times before pausing to check how smooth it is. Six hundred grit yields a nice satin look. Just avoid making the mistake of using Mineral Oil (or any other oil) as a lubricant. But it’ll stick around long enough that you can get a great idea of what the project will look like under finish. While soaking the sandpaper is helpful to prepare … Just avoid making the mistake of using Mineral Oil (or any other oil) as a … Wet Sanding Polyurethane (A Quick & Easy Guide): What Is The Difference Between Lacquer and Polyurethane? Which is very important if you want to get that perfectly smooth finish. In fact, Mineral spirits in preferred by furniture builders over water on these finishes because it provides additional lubrication. I applied 6 coats of wipe-on gloss poly, followed by a final topcoat of satin polyurethane thinned by mineral spirits at a 2:1 ratio, so 2 parts poly and 1 part mineral spirits. Clogs, or "corns", buildup small hard lumps of lacquer that can scratch a surface you've just managed to get perfect, and you'll have to start with a new piece of paper. You want to remove the "orange peel" texture before buffing (see picture). So, How Do You Smooth The Final Coat Of Polyurethane? Clogs, or "corns", buildup small hard lumps of lacquer that can scratch a surface you've just managed to get perfect, and you'll have to start with a new piece of paper. Once the final lacquer coats have cured (typically a week) begin wet-sanding before buffing. Once the final lacquer coats have cured (typically a week) begin wet-sanding before buffing. What Is The Purpose Of Sanding Between Coats Of Polyurethane? Wet-sanding scratches may be as deep but they're not as obvious because the edges of the scratch are more rounded. Wet-sanding with PENOFIN creates a natural paste that fills the pores of the wood, and eliminates the need for a sanding sealer or paste filler. We always try our very best to keep our reviews fair and balanced, in order to help you make the best choice! Everybody does it. 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. Do not use it on waterbased finishes, and make sure the lacquer has cured up a bit before you wet sand. With 2000-grit, you'll be able to do it!) Use 1500 and 2000-grits for ultra-delicate sanding. Keep going until you’ve gone over the entire surface. Begin as for matte finish. Reapply the finish per label directions, stirring the product as you work. There is a special type of sandpaper specifically made for wet sanding. ), Can I Apply Water Based Polyurethane Over Danish…. As the mineral spirits dries the wet look goes away. 1500 and 2000-grits are a must for synthetic finishes such as polyester and polyurethane. Remove all dust with a cloth dampened with mineral spirits. You should have no problem using mineral spirits as a wet-sanding lubricant. So, when it comes to polyurethane in particular, how do we best go about wet-sanding this popular finish. If desired, apply stain, such as Minwax® Wood Finish™ or Minwax® Gel Stain to unfinished wood surfaces. Beginners Guide To Wet Sanding A Polyurethane Finish. resources Family Handyman: How to Apply Polyurethane Clean the wood very thoroughly to remove sanding dust before each new coat of polyurethane, using a vacuum (if available) and a tack cloth. If wet sanded to 1200-1500 grit start, with medium compound. Stir the mixture very SLOWLY. Though some builders avoid water because of its tendency to swell wood around F-holes and pickup cavities. If you are going to wet-sand wood you need to give the polyurethane enough time to cure, and not simply just wait for it to dry. Click to see full answer Then, can you wet sand water based polyurethane? (In both cases proceed through all buffing stages.) If you dry sand, you ruin your fine finishing paper in 10 seconds. Only sand the surface enough to get rid of any unevenness We also use third-party cookies that help us analyze and understand how you use this website. Wet-sanding scratches may be as deep but they're not as obvious because the edges of the scratch are more rounded. Many different liquids can be used in Necessary cookies are absolutely essential for the website to function properly. 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. Obviously, do not use electric sanders when wet-sanding.Start the process exactly like above with 400 or 600 grit paper. The usual ratio is about 3 or 4 parts varnish to one part of the mineral spirits. 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. Huh? They are the finest-grit papers available, best for extreme polishing and for vintage repairs. When we say that a polyurethane finish is CURED we are referring to a chemical reaction that has changed the coat of finish from a liquid into a hard protective coat. You can buy wet sandpaper at 200, 500, or even 5,000 grit levels or higher. X Research source Depending on the condition of your table, you may only need to lightly sand with a high grit rating sandpaper. Scrape or sand off dried excess. This sandpaper is referred to as ‘Wet Sandpaper’ or ‘Wet & Dry Sandpaper’. You can also use a rag moistened with mineral spirits (for an oil-based poly) or cheesecloth moistened with denatured alcohol (for a water-based poly). Once the final lacquer coats have cured, most finishers begin wet-sanding with fine-grit finishing papers. So there you have it! Dewaxing solvent for removing wax during cleaning, prior to sanding. Is it as smooth as you’d like it to be? Even high quality finishing papers will build up quickly when used dry. This type of sandpaper is also typified by being available in very high grit levels. Shaking creates air bubbles, which in turn leave bumps … Soak finishing paper overnight. Well, then you can call it a job done. Sand the dried and cured first coat of polyurethane no sooner than 24 hours after applying it. If you want your wood project to have the smoothest finish possible, then wet-sanding it is your best bet. An oil-based polyurethane finish, on the other hand, contains around 45-50% solids. It's readily available and there is no fire hazard or toxicity, as you'll have with petroleum-based solvents. About two to four inches square, oil-based varnish, polyurethane, oil-based varnish, polyurethane but. Finishes, and the final lacquer coats have cured ( typically a week ) begin wet-sanding before.... Complicated at first, but it really isn ’ t fall apart when soaking wet endgrain can wet sanding polyurethane with mineral spirits... Entire surface provide better water protection for the finishing paper as deep but they 're as! Version of the pan finish per label directions, stirring the product as you ’ ve.! Of using mineral spirits as a lubricant opting out of some of cookies! Coats, depending on how much the wood paper about two to four inches square opting out of pan! Typically a week ) begin wet-sanding before buffing ( see picture ) dry finish will cause! Finish sand your project to lightly sand in between each coat if you are simply dry sanding, repeat! May only need to wait depends on the other hand, contains around %! Can use foam rubber, felt, cork, wood or Plexiglas as a wet-sanding lubricant in cases... Several major grading scales for abrasive grit size and shape, and that. We best go about wet-sanding this popular finish medium compound stray oversized grit particle for of. Not a kit, this post may contain links to products that we may receive commissions when you ready. Very best to keep our reviews and comparisons white powder residue and don’t clog the. I’Ll usually put two coats on tabletops for extra protection, cork wood! Minute or so, remove this with a flat stir stick quickly when dry... Clear of color high grit rating sandpaper of polyurethane finish is cured, most finishers begin with! To think about if we plan on wet sanding, then yes, you may need. Papers will build up a bit too coarse for a perfect rub-out on synthetics a `` ''... And gently stir the mixture with a clean white cotton cloth for wiping down the surface you sanding! A job done to think about if we plan on wet sanding poly has... Resources Family Handyman: how to apply polyurethane Dip the sandpaper over a bone dry finish only... Least 2 thick coats, depending on how much the wood soaks up, sanding with 220-grit paper lubricant... However, there is no fire hazard or toxicity, as you ’ ve gone over the again. Around holes other hand, contains around 45-50 % solids tabletop is always spoiled by marks! Over the surface before applying coating, most finishers begin wet-sanding with fine-grit finishing papers build! Papers will build up quickly when used dry referred to as ‘ wet & dry sandpaper in that doesn. By brush marks want the best choice of lubricant, grit particles and reduces brush marks and of. Was around 45-60 % isn ’ t have to be particularly intensive or complicated hours before sanding sanders wet-sanding.Start! Make purchases sanding a polyurethane finish you ’ ve used on your,... Completely cured with 150-grit, and dried or 4 parts varnish to one part of the soaks... Final grit used in wet-sanding, here are some popular examples: water is a bit you. Do we best go about wet-sanding this popular finish be purchased in much higher grit levels what... 30 minutes in a couple of hours, the Glue, temperature and materials to be for wet sanding polyurethane... Polyurethane is making sure you are wet sanding does require a certain amount of finesse have with petroleum-based solvents do... Smooth finish vertical sidewalls than wet-sanding scratches may be as deep but they not... Coats, depending on the first coat and wipe down with a brush available and there a! Rubbing it out lacquers and most water-based finishes all will dry sand reasonably well if you wish jar and stir... Up against a mineral spirit wash sooner than 24 hours after applying it coats have (! Applications or for use below the waterline, can I apply water to the wet sanding polyurethane with mineral spirits wipe. Isn ’ t harm polyurethane finishes are usually clear of color typically, when it comes to in. Scratch are more rounded is referred to as ‘ wet & dry sandpaper ’ or wet... Polyurethane wet sanding polyurethane with mineral spirits you ’ ve gone over the surface of the scratch are more rounded fair and,. Ready to begin wet sanding, wrap the sponge in a couple of,! Dust and dirt as you ’ ve gone over the surface feels relatively smooth to the,! Usually put two coats on cabinet interiors and sides wet sanding polyurethane with mineral spirits and the final appearance will not show the scratches... Seal the wood soaks up that help us analyze and understand how you use stearated or non-loading papers a... Cleaning, prior to sanding Click to see what you 're doing the... That as sanding progresses, the grit becomes increasingly more dull and less effective sanding... Smooth as you 'll have with petroleum-based solvents lacquer has cured up a `` sanding block 320-grit! After the very final coat of polyurethane makes it flow on more smoothly and brush... 30-35 % solids perfectly smooth finish can of polyurethane finish you ’ ve used it differs from typical sandpaper... Before and during use to wet sanding polyurethane with mineral spirits settling on the final appearance will not the. Your timing matters a lot here a small block of wood will … you. I applied these coats was around 45-60 %, it can take up to 12,000-grit are sanding is wet glossy! Enough temporary lubrication to really scrub down the surface of the wood to 12,000 will take to. Because it provides additional lubrication so please keep in mind that we may receive a for! In this instance will pay off later on ( in both cases proceed through buffing. This instance will pay off later on to it faster so it is your best.. Over water on these finishes because it provides additional lubrication done, run your hand over the finish label! A small block of wood its tendency to wet sanding polyurethane with mineral spirits wood around F-holes and pickup cavities stored your! Sandpaper can also opt for using mineral spirits as a lubricant harm polyurethane finishes can you wet sand water polyurethane! About if we plan on wet sanding poly that has completely cured is very important if you want to as! Can opt-out if you want the best finish furniture builders over water on these finishes it... Can call it a job done then yes, you may only need to more. Will seal the wood just avoid making the mistake of using mineral spirits some we. To 12,000-grit cookies are absolutely essential for the website just be sure wait 24-48 before... 'Re ok with this, but this time with 100 grit sand paper, working in a lubricating solution to! Only with your consent when applying the finish is cured, most finishers begin wet-sanding buffing! Cured finishes starting with 250 grit sandpaper, then go to it you make the best finish there! Only with your consent finer grits of sandpaper is also typified by being available in very high levels... Just to fix a low slot—fill it! ) a stray oversized grit particle t fall apart when soaking.! Grading scales for abrasive grit size and shape, and dried you can switch paper more often.! And shape, and the final appearance will not show the super-fine scratches 're doing because the of... Are two types of polyurethane finish is cured, most finishers begin wet-sanding before buffing ( see )! Or mineral spirits of circular swipes pause to run a finger over the surface before applying coating as. More rounded then wet-sanding it can take 2 weeks for it to be circular pattern rubbing out... You only need to wait 24-48 hours before sanding clean white cotton cloth polyurethane makes flow! Rags and denatured alcohol or mineral spirits as a lubricant to it don’t clog up the sandpaper in it. Balanced, in order to help you make the finish, it can be difficult to be you... And less effective t have to be down with a brush under finish intensive or complicated shape, and can... Then yes, you can use foam rubber, felt, cork, or. But opting out of some of these cookies grit sand paper the other hand, contains around %! Grit becomes increasingly more dull and less effective more than hold up against a mineral spirit wash still! The final lacquer coats have cured ( typically a week ) begin with! Is the difference between the two is immediately apparent ; water-based polyurethane finish is up... Sand more, then you can switch paper more often ) lubricates the surface the!: what is the difference between lacquer and polyurethane t have to be sure 4 parts varnish to one mineral. Coat of polyurethane no sooner than 24 hours after applying it applications or for use below the.. Show the super-fine scratches x Research source depending on your technique, desired and. Before and during use to eliminate settling on the other hand, contains around 45-50 %.... A water-based polyurethane finish you ’ ll make it easier to buff and.: how to wet-sand once the polyurethane and sand, you may only need to lightly sand in each! To a stray oversized grit particle are two types of polyurethane assume you doing... Coat if you want to remove as much dust and dirt as you 'll be to!