# The Right Sandpaper for the Job



## WoodworkingTalk (Dec 8, 2015)

> Sanding is the first step in creating a finish on any woodworking project. It gets rid of rough edges, removes gross imperfections and gives the wood a smooth surface that's pleasant to the touch. The array of sandpaper choices can be confusing – grit size, materials, closed vs. open coat – but each one has its own particular uses. Sure, you can finish your entire project using only the finest grit sandpaper, but why waste all that time? You'll spend days doing a job that should only take hours. Why not choose the right sandpaper types and get the work done sooner?


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Read More*:
http://www.woodworkingtalk.com/articles/the-right-sandpaper-for-the-job/


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## Jig_saw (May 17, 2015)

I use 3 step sanding by hand using 80, 120, and 220 grit sandpapers. Gives a glass like finish to most hardwoods with two coats of varnish. For better results it is important to be sanding along the grain direction which can be more easily done by hand rather than a power sander.


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## Brian T. (Dec 19, 2012)

In my wood carvings, I find that I always need to "have one more dig" with a knife or a gouge.
The lost grains from worn sandpaper stick in the wood. Kiss of death for expensive ($50+) carving tool edges.
Sandpaper of any grit size shreds the wood surface.

Instead, I make up my own little cabinet scrapers from the hard steel that's used for banding lifts of logs or lumber.
It's a fact that scrapers actually cut the surface wood cells. Fantastic curly little shavings with a 10X magnifier.
The down side is that conifer wood is rarely hard enough to use the scrapers. Leonard Lee confirms that experience.


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## allpurpose (Mar 24, 2016)

I've worked in auto body business for a long time and as an industrial painter on heavy machinery. Random orbit sanders are great if you have the time to practice keeping the sanding surface flat and I mean almost dead flat. Otherwise they can really dig into the work surface really fast and ruin your project. Keep a firm grip on them and let the sand paper do the work for you. Like everything else in woodworking or any kind of skilled trade practice is king. If you're going to use a random orbit sander for the first time it's a good idea to find some scrap material to learn how to keep the sanding pad flat.


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## allpurpose (Mar 24, 2016)

I've been using the sand paper made by 3M lately..It claims to last 15 times longer which is probably hyperboly, but it's still pretty good stuff and does great for flexing around odd shapes. I had to sand an old dresser I refinished with lots of convex and concave angles and the paper did a fantastic job of flexing right where it needed to be. I did almost everything with 150 till the final sanding and switched to 320.. It smoothed out all of the tiny scratches using just a few sheets.


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## Tony B (Jul 30, 2008)

I use only hardwoods. I use most of the common and some exotic hardwood species. My favorites are red oak and padouk. 

Normally when I bought my furniture grade lumber, I always paid the supplier to plane it down for me. I had a 20" planer and an 8" joiner, but it was more cost effective to have the supplier surface 3 sides (S3S), which means top, bottom and one edge(straight line rip).
I rarely ever needed to sand below 120 grit and rarely ever sanded bare wood above 150 to 180. This is in compliance with the pre-catalyzed lacquer recommendations for bare wood on their Product Data Sheets (PDS). It is important that 
that you dont go finer than the manufacturers recommendations. All finishing products have binders, the chemical that makes the finish stick to the wood or to itself. Essentially, it is a glue. The more gluing surface, the better the bond - within reason. When you sand, you are removing wood by scratching the surface and making the equivalent of eroding mountains with steep sides. The steeper the sides, the more surface area for the finish to stick to. The finer grits will leave less steep slopes with resulting less adhesion. Each manufacturers product may have different recommended grits. For example, lets get back to my pre-cat lacquer. The manufacturer recommends the bare wood surface to have been sanded from 150 to 180 grit. Now, when it comes to 2nd and 3rd coats they recommend 220 to 320 grit. Thats because the second and third coats are not only depending on the depth and angle of the mountain slopes ( anchor profile or tooth) for adhesion but are now benefited by the chemical bonding also. If you think you should slightly overbuild, you are wrong. Just stick to the recommendations of the manufacturer.

Anything above 220 or 320 is normally used when achieving a mirror finish. This in itself is another process that normally progresses from 320 up to about 1500 grit and then followed by 3 processes of buffing. If you don't do each stage as required and understood, you are actually lessening the quality of the finish. 

There is more to sanding than meets the eye. It is not rocket science, just believe the manufacturers recommendations. They are usually called Product Data Sheets (PDS) or something similar. Do NOT confuse this with MSDS (material safety data sheets).


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## Tony B (Jul 30, 2008)

One more thing: Some abrasive paper is actually labeled for hand sanding or for machine sanding. It has to do with the quality of the paper or backing sheet. If you use 'for hand sanding' on a power sander, it will wear out almost immediately. Which brings about another myth. Used 120 grit sandpaper is not like using 150 or 180 grit. It is more like using worn out 120 grit. It feels smoother because the sharp pieces of grit are now broken and smoothed out and many pieces of abrasive grit have fallen off. When using an electric (power) sander, the sandpaper does not last all that long. You have to change out paper regularly or stand there sanding for a while and not really getting anywhere. 
Cheap sandpaper is NOT ECONOMICAL. Sanding is really quite expensive for what you are doing. Get used to it.


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## Steve Neul (Sep 2, 2011)

I don't see it as that simple to have a routine regimen for sandpaper grit. It would vary depending on the wood and the sanding equipment used. What might work for oak wouldn't work for basswood, the softer wood would need to be sanded to a finer grit. Then if you had a good random orbital sander that run at a higher speed it would be easier to omit some of the finer grits than if you had a poor sander that ran slow. Each person needs to tune the grit paper depending on the wood they use and the equipment they have. This is probably the reason there are so many grits available.


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## Tony B (Jul 30, 2008)

I dont have a regimen, I mere stated that "I" rarely ever sand below 120 grit and above 150 to 180. The 120 grit was prefaced in an earlier paragraph based on hardwood coming out of a planer. If you need heavier than 120 coming out of a planer, there is something wrong with the planer. 
I grant you that on the lower grits sandpaper is way more aggressive and effective on soft wood, however, that would mean that you would start with a higher grit than 120. That only makes sense. But once you get up to the 150 to 180 grit range, now it's more about the finish requirements than the wood itself. Assuming a hard finish, not an oil finish, the first coat whether primer, lacquer, poly, etc, the finish chemical takes on a life of it's own. It now becomes the new surface. 
As for jumping up grit numbers. Consider that each grit we jump up to is to erase or remove the grit before it and give us a new scratch pattern. Depending on the hardness of the wood determines how much longer we have to spend in the higher grit to remove the tops of the heavier grit below. If I go from 120 to 150 to 180 and then 220, I will spend very little time removing the scratches below it. If I jump from 120 to 220, I still have to dig down deeper to get to the depth cut by the 120. That pattern has been engraved in there and it dont care what grit you use after that. So, yes, I could skip the inbetween grits but spend more time on digging and surface removal to get down to the 120 deeper scratches. Everyone is different so you decide how you want to do it.


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## woodnthings (Jan 24, 2009)

*Another opinion by Bob Flexner*

Bob Flexner wrote the book on finishes...literally!
http://www.shopwoodworking.com/flexner-on-finishing-pdf-y3249


Here's what he says about sanding:

http://www.popularwoodworking.com/techniques/rules_for_sanding_wood

How the grits compare:


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## aardvark (Sep 29, 2011)

What isn't being discussed is the final finish material, like lacquer, poly, other.
In fact I've been using epoxy which the manufacturer claims is equal to 50 coats of the other finishes. I don't buy their claims,,, maybe it's 10 to 15 times.

But what I've found with epoxy is the finish is so thick that a lot of times I'll stop sanding at 80 grit and have even stopped at 40 grit before. Even stopping at 80, the sanding scratches are not often visible. I've lately been going down to 120, just for the heck of it.

So what I've been doing lately is putting on 1 to 2 brush coats with the epoxy, letting it dry for 2 days and sanding the surface. Most people don't like a extreme hi-gloss finish. After sanded, I've been spray coating with a water based poly and I'm done..., but my last project I started sanding the epoxy surface way down to 600 grit and beyond, and then getting out the rubbing/buffing compounds to get a epoxy tough satin finish.

So my point is that final finishes also matter.
My reason for using epoxy is it makes table top finishes nearly indestructible.


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