Live edge maple stump slab - saw marks?

[Donald Alles]

I've just started prepping a 100-year-old hard maple stump slap for finish, and I notice there are horizontal striations in the top that look to be some kind of saw marks. I have attached a pic, and if you zoom in you'll see these striations running at about a 45 degree angle from the horizontal plane of the pic. As I run my fingers over the striations I can feel a very slight bump to them.
Will these striations disappear with aggressive sanding? What grit would you recommend? Would planing be more effective or faster?

[Rod Sheridan]

Hi Donald, I would sand with a 60 grit, followed by 100 then maybe 150 and 220 grit..........Regards, Rod.

P.S. Is the slab dry?

[Pat Barry]

The finished product will look better and better as the surface gets sanded to progressively higher grits. I would go to at least 220 as Rod suggested, might even try 320 to see what happens

[Chris Padilla]

Sanding or handplaning will do the trick. What is your planned finish for this cross-section? What are the plans for this?

Have you measured the moisture content? You may wish to decoratively keep those splits from opening up any further. A nice dutchman (bowtie) in contrasting wood can be nice.

[Tim McCarthy]

I have worked with several slabs similar to that. I would bet dollars to doughnuts that the marks are from the chain saw. Where are you? If it's less than 36" wide at any point you could bring it over to my house and run it through my drum sander. I use 36 / 60 grit then switch to 60 / 80 grit on the two drums. It's not quick but it's not too tedious either. Makes them nice and flat and ready for the 6" ROS. Bring gloves and a six pack!! LOL

[Bill Space]

Where are you and where are you! LOL.

MAYBE YOU BOTH SHOULD PUT YOUR LOCATION IN YOUR PROFILE! ��

[John K Jordan]

Donald, sometimes marks are what we used to call "subsurface deformation" in the metallography lab - damage below the surface. In wood this can sometimes be far below if fibers are torn and pulled out instead of the surface simply being scratched. If the surface is just scratched by the saw, it can be sanded away fairly easily. If the fibers are torn out the marks may go "deep" below the surface and take a huge amount of sanding to get to undamaged wood. Torn fibers are especially a problem on end grain such as this. Some species seem to be worse than others but I don't know about hard maple.

The problem with excessive sanding is it is hard to keep the surface perfectly flat.

If the surface is otherwise sanded smooth with fine grit sometimes you can tell what's what by examining with a strong magnifier, sometimes not. If you sand with 60 thru 220 and marks still remain the fibers may in fact be torn deeper than you can easily sand. In that case it might be quicker to plane, rout, or otherwise remove the top few millimeters and get down to undamaged wood and then sand.

JKJ

[Donald Alles]

I'm in Ann Arbor MI. Anywhere close?