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The best way so far that I have found is using a scraper and a 3in by 14in mdf board with 80 and 120 grit paper, and curved rubber with sandpaper. I tried a 120 grit on the belt sander got too many ripples. Can/t use spindle sander back and top arch. Don/t like changing grits on my thickness sander too time consuming What methods do you use to flatten your guitar sides after it has been glued up thanks ernie.

Hi Ernie,

I use a scraper in a Veritas scraper holder. This stops my fingers and thumbs from getting hurt...

Cheers,
Dave F.

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Cambrian Guitars

"There goes Mister Tic-Tac out the back with some bric-brac from the knick-knack rack"

The drum of my 6x89 edge sander.

First: Hi Ernie. I live in KC and it is good to see another builder from the area on the forum.

Second: Your question is a bit confusing. At least to me. Are you asking about the best way to thickness sides prior to bending? I think you might be given the comment about using a 3in by 14in board with sand paper attached to it (not much use for such a lengthy sanding stick on bent sides), but the "spindle sander" and "top arch" language is confusing and also the part about "after it has been glued up." Clarification of the exact procedure you are speaking of would probably result in more, better responses.

If you are asking about unbent sides, then I would say use your thickness sander with 80 grit to level and thickness the sides. Then bend away. There is no need to sand past 80 grit at this stage IMO. You will have to level bindings out anyway, and may suggest insetting the bindings in from the sides ever so slightly and then bringing the sides down to level with the bindings (helps reduce the risk of sanding your binding too thin in spots). In the process, you can work down through finer grits. Sides can get wavy (spell check didn't underline this one, so I guess that's a word) or dish a bit during the bending process, so sanding too finely prior to bending probably would be time wasted.

If you are asking about after the sides are bent and the box is closed, I have found a tip from another forum member useful. Make a shallow rabbit cut where the bindings will go to cut a small relief in the top and back plate. This takes the end-grain out of the equation and makes truing the sides easier. I just use a flat sanding block lined with 1/16 quark and sand away with whatever grit I think the problems call for in all parts but the waist, where I use a 2 1/2 pipe lined with quark and sandpaper to clean up the side. I have also made a flexible sanding block by cutting lots of kerfs into say 3/4 in ply and sticking sandpaper to the unkerfed side. Works well also (another tip from Hesh I believe).

Best Regards,

Aaron

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Aaron Craig

I've tried everything (except the scraper holder) and always go back to my trusty side sanding block I made 6 or 7 years ago with a hard round rubber block for the waist. A good guitar vise was the big breakthrough for me. Makes it so much easier. I like the holder Dave.

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It's not what you don't know that hurts you, it's what you do know that's wrong.

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Hi What is quark?? yes I do use a sanding block and round 2 in rubber form with sandpaper. I like your idea of the rabbett, makes sense. Have a verita scrapers holder dont like using it to scrape sides feels awkward to me . Yes after sides are glued to top and back . Checked into rolling pin sander. Don/t think I will try it , one mistake and a huge divet in your sides ouch. Keep those ideas comin thanks ernie

KC builders unite!

I've only done one, but mostly same as Aaron. 80 grit on a flat cork-lined sanding block that I use for just about everything, and a cylindrical block for the waist. I actually just used my LMI white glue bottle... little squishy. I think I'll look for a 2.5" or so PVC pipe this time and line that with cork as well. Mostly circular type sanding motions.

I did all the level sanding at the end, after bindings were installed so no end grain to deal with. I quit with still a few very shallow pits, because the sides were pretty thin already and I didn't want to go too far. Just sanded those with my fingers to smooth them with the finer grits, after going over all the surface with the blocks. Can't find them now.

So... probably no easier than what you've tried already. But the cork lining definitely speed things up, because it conforms to the curved surface just a bit, getting much more contact area than a hard block.

I just take my wife's marble rolling-pin and tape some sandpaper to it and just us it to sand the sides (after closing the box). Since only the tangential point of the pin will touch the side and it is used just like a block, it won't leave a divot, but you do need to rotate the pin to utilize all of the sandpaper.

"Quark" appears to be my phonetic spelling of "cork."

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Aaron Craig

A 2 inch dowel here, with sandpaper taped to it for the cutaway.