Help! Newbie with Sander marks...How to fix??

Mandie

So I've built my harvest table. I stupidly decided to sand it, knowing nothing about sanding.

I sanded it with 60 grit( Yes, i know. its too course, as i've already felt the wrath from a friend about how dumb that was)

And now I'm stuck with a table with sander marks ALL OVER IT.

PPLLEEAASSEE help me. How do I fix this? I have a palm sander.

Is there a way to get the lumber back to its original grain without marks?

joecaption

Just use something like a 120 grit and sand them out.
Always let the sander do the work, do not try to tip it, keep it laying flat.
Keep an eye on the sand paper if it's loaded up change it or your just going to be making more scratches.
With a palm sander it may take a while. A random orbital would be much faster.

jschaben

Hi - not a problem, just sand it down with about 100 grit and then do it again with about 150 grit. I usually stop at about 150 or 180 if painting the project, for staining I will go out to 220 or even 320 depending. You mentioned grain so I'm assuming a stain finish. In this case you didn't waste your time with the 60 grit, you would likely have had to do this step anyway to avoid visible machining marks from saw and planer blades. Just continue to a 220 grit and a light wipe with a rag dampened with mineral spirits will show up any marks the stain will bring out.

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John Schaben

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sdsester

No way now but to exercise patience and reduce the grit of the paper on your way to 120 or finer. If you carved it up at 60 grit, you may have to use 80 for your next pass, then 100, etc. 120 will work but will take forever to get out 60 grit gouges.

When you get close to your final sanding finish, you may need to apply a sanding sealer depending on what type of wood it is.

As Joe suggests, a random orbital sander works pretty fast and is pretty hard for a novice to do too much damage with. I would use a belt sander on a long table top to start but they take some practice. I have a little mouse orbital for detail work.

Heed Joe's advice to keep the sandpaper parallel to the surface and change it often. If you do not use an orbital sander, make sure you are sanding the direction of the grain and not across it or you will never get a nice surface.

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RWCustom

Yeah, the previous posts pretty much hit the nail on the head.

If you are staining and clear coating the surface then maybe start with 80-100 grit and keep methodically working the surface while sanding with the grain, and keep your sanding block/tool perfectly flat. Make sure you properly position your lighting to give you the best chance to see any imperfections throughout this whole process. The whole idea is to locate the problem areas and take care of them long before you apply any finish coats. Next, jump up to 150, and then 220. Once you're satisfied with the surface take a rag with mineral spirits and very lightly wipe the surface down. This will temporarily darken the wood and help highlight any imperfections, and it will also evaporate quickly. I have no idea what species of wood you used, or what type of finishing process you have lined up, so the best advice I can give is to make sure that your finishing products are compatible with one another to give you a beautiful, well bonded, and durable finish. Make sure to follow the directions on the can/s of material and don't try and rush it. If your clear coat says to wait 48 hours for your oil based stain to completely cure before applying it, then just do it. After all of that sanding the last thing you want to do is have a topcoat failure and then be forced to do it all over again. Again, just make sure that ALL of your finishing products are complatible with one another for maximum performance and ease of application.

It is also a good idea to very lightly sand between topcoats, and then carefully wipe the entire surface down to remove any dust or particles. If you are using a polyurethane this will help it to smooth out and lay down more flat, especially since your first topcoat will raise the surface grain in the wood. Once the topcoat hardens the raised fibers will be trapped/sealed in it and the light sanding will smooth everything out again. The fibers will only raise once, so any subsequent ultra light sanding between coats will just be to knock off any burrs that crop up for whatever reason. Oh yeah, almost forgot, if you finished out the raw wood with 220 grit as your final sandpaper then absolutely do not use anything any grittier to knock off the burrs between coats. Heck, a 320 or something even a little finer is plenty since you're not trying to remove material, just lightly scuff the surface (to give the next coat maximum bond) and knock off the burrs.

Good luck with your project!

smalpierre

Like everyone said - work your way up the grits to get rid of the marks. Another benefit of the random orbit sander - like a 6" disc - is that it will stay flatter, and since you're getting more area of pad you won't have as much chance of having lines or grooves at the edges of your passes.