How to remove all sanding marks on tabletop

[dennis thompson]

I am building a library table. I sanded the top & thought I had sanded out all the sanding marks which were in it, however upon putting the stain on it I found several sanding marks I hadn't eliminated,. I'm now sanding it down again. Is there a way to insure during the first sanding that all sanding marks are removed?
Thanks
Dennis

[Ed Sallee]

A good clean up using Mineral Spirits always works well for me. It evaporates quickly enough...

[Joe Hardesty]

Inspect the surface with a bright directional light. The light should be set at a low angle so that it casts shadows of the imperfections. Move the light around and inspect from several different directions.

[John Thompson]

Mineral spirits will highlight any machine marks.. sanding marks.. dents.. etc. as Ed stated. A very light wipe and I use Naptha as it evaporates much quicker. But.. do allow it to completely dry before adding stain or finish or you have a layer of oil based solvent sitting on top and will affect what you are putting on.. especially stain which you want to cover evenly on the dry surface.

Sarge..

[glenn bradley]

Remembering that when we sand, we are not smoothing things out, we are scratching them uniformly. Be sure the surface is thoroughly cleaned off as you move up in grits. Loose 150grit particles left on the surface can be rubbed in with your 220 paper leaving deep scars relative to the scratches that the 220 is making. These can be particularly nasty if you accidentally rub across the grain.

As recommended, mineral spirits wiped on and a bright light shown across the surface will expose the details. The MS will dry quickly but if you're impatient hit it with a blow gun from a distance (you don't want to spray contaminants onto your surface if you aren't running a dryer and a filter).

FWW has quite a few good articles on sanding but this one (http://www.taunton.com/finewoodworking/FWNPDF/011173040.pdf) may be particularly appropriate.

[Chris Padilla]

Tell us about your method for sanding. Do you go through all the grits? What kind of sander are you using? Random orbit sander? Linear sander? Belt sander?

I think you'll find that the ROS (random orbit sander) typically is the ideal sander to use for large surfaces like a table top due to the type of scratch pattern it produces: random! :)

Here is what I've been doing on a project I've been working on. It is a walnut Tansu. The walnut veneer was all drum sanded with either 100 or 120 grit sandpaper on the drum sander (to get the walnut veneer all down to a uniform thickness of 1/16"). This produces long straight scratch marks in the walnut.

After applying the veneer, I started with 80 grit on my ROS. In some cases, especially around crotch figure in the walnut (which is harder, denser wood), it took a bit of time to completely remove the straight scratch marks the drum sander left. Using the light method and bending up and down and looking at the surface from different angles, you can easily see these marks. Wiping with a solvent (alcohol, mineral spirits, naptha, acetone, etc.) also works but I prefer to not put anything on the surface of the wood if I can help it so I use the "bend and look" method.

I then progress through all the grits: 80, 100, 120, 150, and 180. The 80 takes the longest but once all the drum sander marks are gone, the other grits go a lot faster. Taking the sanding beyond 180 grit is a personal preference...heck, you could stop at 150 grit, too. It all depends on what you want to achieve. For surfaces that won't get seen too much, I usually go to 180 and stop. For surfaces that may be seen a lot or touched, I'll usually go beyond and hit the 220, 240, 320, 400, etc. area until I reach a level of feel I want.

Glenn hit on somthing interesting: clean up or blow off or wipe down your surface well between grits. If your sander has a dust port, be sure to hook up a vacuum to it. I use Festool sanders and they capture what seems to be about 99% of the dust from sanding. It really feels like you are doing nothing because you have no dust left from sanding but one swipe of your hand on the surface tells you otherwise. :)

[Chris Padilla]

FWW has quite a few good articles on sanding but this one (http://www.taunton.com/finewoodworking/FWNPDF/011173040.pdf) may be particularly appropriate.

Looks like you may need to be a member to see that article, Glenn.

[Andy Bardowell]

Great reply Chris, might be an article there. Also to Chris's point I like to switch to the linear sander for the final grit with the grain or even hand sand that one. I also like to go up another grit or two on the end grain because it absorbs stain faster and deeper.

[dennis thompson]

Thanks for all the replies, they are very helpful.
I started with a belt sander & then a ROS. I think most of the marks were from the belt sander,I have never had any luck with my belt sander (It's a Bosch) so I think I better retire it & stick with the ROS. I just finished resanding the top with an 80 grit on my ROS & plan to go to 120 & then 150.I'm using a General oil based gel stain & the directions say not to sand above 150 grit.
Dennis

[Greg Cole]

By not sanding in the first place.:rolleyes:
Seriously, if you ask me sanding is the devils work. I've gone to mostly neander methods for smoothing and final surface finish.
A smooth plane (#4 or 4 1/2) and a card scraper. There's a bit of a learning curve, but you won't look back.

Just my smart aleck $0.02. But the others have you well covered for the how to's for the devils work.

[glenn bradley]

Looks like you may need to be a member to see that article, Glenn.

Ooops, sorry about that:rolleyes:. You are correct. Basically it just goes over much of what has been said here; they just go through it all in a nice orderly fashion. They got nuthin' on us :D except maybe some fancy pictures of a guy shining a light across a wet surface;).

[Von Bickley]

I started with a belt sander & then a ROS.
Dennis

I usually think of a belt sander as being used for "Wood Removal". I'm not good enought with a belt sander to put one on a table top. I would stick with the ROS....... :)

[Myk Rian]

I sand each grit twice. After the first, I'll dampen it a bit with water to raise the grain. Sand it again, then I'll move to the next grit and do it twice again.

[rich murray]

When I finish with one grit I look (closely!) to see that all cross-grain scratches are removed before I move to the next grit. I think it is a good idea to periodically dust off the surface even while using the same grit so as to remove bits of loose grit. Don't skip grits. Inspect the surface closely before moving to the next grit, use mineral spirits if you want. My last step is hand sanding with the grain. Also knowing what to look for is important. Once I made a kitchen table with round top that I sanded with a pneumatic random orbital sander, careful not to skip grits, etc. When I applied the stain the whole top was covered with small semicircular scratches, little commas saying, "pause, then, pause, then, pause, then." I had not kept the surface dusted off, and i had been on the lookout only for those straight cross-grain scratches. Scratches fill with fine dust and hide. I don't know anyone who likes sanding, but you'd best give it its due.

[Frank Drew]

Dennis,

On something like a table top, I'd only use a belt sander with a sanding frame, which turns what can be a divot-maker into a precision tool. And 80 grit might be more aggressive than you need if you've already planed the material.

To me, sanding and finishing are the most annoying parts of making furniture, especially since they often come at a point when you've been working on whatever it is for a while now and all you're interested in is getting the damn thing done and out the door. But you can't skimp on these steps, and how well you sand determines how good the finish looks.

[I could have just written, "What Rich Murray said."]

[Chris Padilla]

Great reply Chris, might be an article there. Also to Chris's point I like to switch to the linear sander for the final grit with the grain or even hand sand that one. I also like to go up another grit or two on the end grain because it absorbs stain faster and deeper.

That is a good idea, Andy, about switching to final linear hand sanding or, maybe, more appropriate, a "with the grain" sanding by hand.

I'm a big "wiping varnish" and/or "oil/varnish blend" user as I hate complicated finishing steps/procedures and IMO, for pieces going into a home, that is all one needs. I like to do the final sanding using the oil finish as a lubricant and a wet/dry very fine grit carbide sandpaper (400 grit area). I have no idea if the slurry created does anything but I really enjoy how silky smooth it makes the surface.

As a final step for my finishing and especially on surfaces that might see some wear, I'll go ahead and wax it.

[Prashun Patel]

A ROS is a good versatile tool, but I don't like it for removing deeper scratches or localized planer marks. It's easy to get 'rings' if you linger on a spot too long.

I've come to really love using a scraper or bench plane to remove tearout and deep plane marks. Then I switch to the ROS at 100, 150, 220. A final hand sand at 220 is critical to remove ALL swirls from the last 220. You don't need to go at it too hard by hand though.

[David DeCristoforo]

I know this is not the "Neander" forum but a cabinet scraper is the ticket for final surface prep.

[John Thompson]

In my shop a belt sander is used on decks.. etc. I use a card scraper after the stock comes off the planer to remove any machine marks.. 120-150-180 on hardwood and 120-150-220 on softwood. I vacuum the stock between grits and apply a light coat of distilled water (the minerals have been removed) before the last grit to raise grain intentionally before it gets the final pass.

I keep the ROS moving and I find it doesn't require more than a back and forth pass on each run the width of the ROS to do the job. I used to spend way too much time sanding and finally came to the realization that it was really over-kill as the job was done well before I finished.

BTW.. Myk.... if I understand correctly, why do you raise the grain after each grit in lieu of just before the last which accomplishes the same end result? Just curious if you know something I don't?

Sarge

[Julian Nicks]

I'm jumping on the card scraper/smoother plane bandwagon here also. You can fore go the many grits of paper, and many hours of sanding by just using the proper tools, not sandpaper. All I do is use a plane to get close, then hit the entire surface with a card scraper, then HAND sand with 220 grit on a sanding block. I can level and flatten a surface much faster than mindlessly sanding through the grits with a ROS.

[Myk Rian]

BTW.. Myk.... if I understand correctly, why do you raise the grain after each grit in lieu of just before the last which accomplishes the same end result? Just curious if you know something I don't?

Sarge
I feel it makes it easier for the next grit to work. Something my grandfather showed me, a lonnnnng time ago.

[Michael Trivette]

Really I do love sanding...........just weird I guess

The common wisdom from the mags I have read (and the nutcase from my Woodcraft) seems to be that you sand to 220 and you done.

I was taught different woods require differnt grits of paper for final sanding.

220 or even 180 is great for Maple or Oak
150 or so for more dense woods

320 is the least I use for Poplar or Pine
Also starting with 80 is too low for soft woods unless you are removing stock
I find after running through the planer starting at 150 works great for softwoods

I do use light to see sanding marks and such but I was taught to sand by feel.

These are general guidelines on what works easiest for me.

I also prefer water to mineral spirits for raising the grain.
Sorry I have no lodgic to backup that statement but I have tried both and I like the water better but It does take a bit longer to dry.

[Kyle Iwamoto]

My .02 would be to stop using the belt sander. I think it's a rough carpenter's (no offense to anyone) tool. I takes off a lot of wood fast. Fine work? No.

My additional .02 would be to use quality sandpaper, especially the 80 to 100 level. If the paper is poor quality, it could (and I've experienced this) have a 30 grit sized ROCK in it and as you are sanding, you're generating this nice deep 30 grit gouge where ever you go. This unfortunantly shows up when you're doing the 220 grit stage. I kept thinking why can't I get those scratches out?

Don't want to get into a scraper war, but sandpaper is a tool, and requires little to no "skill". Yep, pretty "mindless". Using a card scraper requires a LOT of practice. Scraping a table top? Long time, sore muscles.... ROS = Fast. Small things? Scrapers do rule....

[David Keller NC]

"I am building a library table. I sanded the top & thought I had sanded out all the sanding marks which were in it, however upon putting the stain on it I found several sanding marks I hadn't eliminated,. I'm now sanding it down again. Is there a way to insure during the first sanding that all sanding marks are removed?"

Dennis - a fair number of these points have been tangentially addressed with previous responses, but thought I'd list them here and add a couple:

A belt sander is a roughing tool. It is designed to flatten a surface (with an appropriate frame) and reduce its thickness. It is not a tool designed to "clean up" a surface after a planer unless it's badly torn out.

It is absolutely impossible to remove all sanding scratches unless you never touched the surface with sandpaper in the first place. If you're sanding, you want to level the surface, replace the big and deep scratches with much smaller ones, and finally, line up the scratches with the grain in the wood.

A random orbit sander is not designed to remove a lot of the surface - you can render a table top badly wavy or uneven by using really coarse sandpaper in an ROS. Typically, 100 grit is the absolute lowest I go, and often start with 150.

The best method to finish a table top really is a handplane and a card scraper, and leave it at that if it's to be finished with a clear film or oil without pigment in it. If it's to be stained, the best method is use a hand plane and a card scraper, and then follow up with light hand-sanding with 220 grit paper with the grain. Generally speaking, you can finish a top with a hand paper in about 1/5th - 1/10th of the time necessary use a ROS and progress from 100 grit, 150 grit, and 220 grit, particularly if it's a hard wood like maple.

Regardless of what method you choose, it is essential that you follow up the last use of a ROS with hand-sanding with the grain. If you don't, cross-grain scratches will snatch pigment from the stain and hold it, making nice, ugly scratches quite visible on the finished piece.