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Maybe a silly question but is there any reason one should not sand at least the presentation side of a Rosewood side to 180-220 grit before bending? They come off the thk sander with 120 grit off-grain scratches that are challenging to see and difficult to remove after bending. I have not bent a ton of sides but I know the oils scorch sometimes during bending and *might* be more difficult to remove if pre-sanded smooth.

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Measure Twice,

Karl Borum

I always sand to 220 both sides before bending by hand. Makes less work later on. If I start to get scorching I wet a piece of t-shirt and put it between the iron and the wood.

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Steve Smith
"Music is what feelings sound like"

One thing I learned on this last build I did was to use 240grit paper on my drum sander as the final pass(es). Got it cheap on Amazon and it works great, especially on the top. I don’t have to worry about final thickness after sanding out 80 or 120 grit scratches.

It’s a a lot easier to sand out the drum sand scratches when the wood is flat. Rather than change the paper in the drum sander, I sand it to 220 with a ROS before I bend.

For me there would be no value in that, as after the box is closed but before routing the binding channels, I level sand the sides with 60 grit on a hard block. I also flush sand the bindings with 60 grit on a hard block followed by 100 grit.

There is value in sanding the back with 150 grit on the drum sander in the final passes.

I thickness sand 0.15mm oversized and scrape both the interior and exterior faces of the side to achieve my final pre-bent thickness. Both sides are perfectly clean meaning cleanup after bending only requires 220 paper.

I sand P60/80/100/150 as required on the drum sander to bending thickness.
I use an elevate V2 rolling pin sander with P120 to level sides before binding, then normally a scraper on binding/sides.
Then P180 on blocks for the sides and an ROS with P180 on the top and soundboard.
Just before finishing I'll use P240 on everything or higher, depending on what I'm finishing with.

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.