Help figure out this staining problem?

[®smpr_fi_mac®]

Red oak.  Sanded 120, 180, 220.  Wiped clean between each.  Also marked entire surface with pencil before each grit to ensure complete, even coverage. 

Varathane Dark Walnut oil based stain.  Flooded on with lint free cloth.  Wiped clean with the same a few minutes later. 

The top isn't evenly colored and I cannot imagine why.  

I know I need to sand it back down to fix it; I imagine I need to wait a few days to ensure the stain has fully cured, no?

Will sanding it down fix this?  Do I need to do something else?

Please help!

[®smpr_fi_mac®]

Maybe it's the wiping pattern?  This angle and light makes me think that.

[®smpr_fi_mac®]

After sleeping on it, I wonder whether I should have started with 80 and then moved forward.  I did use 80 on parts to knock down really rough spots. 

Maybe not doing the whole thing with 80 caused this weird staining?

Either way, I'll resand it tonight.

[jteneyck]

After sleeping on it, I wonder whether I should have started with 80 and then moved forward.  I did use 80 on parts to knock down really rough spots. 

Maybe not doing the whole thing with 80 caused this weird staining?

Either way, I'll resand it tonight.

Maybe, but you said you put pencil marks across it and sanded each grit until they were gone, but I can't think of a better explanation.  When you resand it I would stop at 150 or 180 grit.  Sanding to finer grits on open pore woods increases the chance of ending up with a non-uniform surface because of the hardness difference between the growth rings and also increases the contrast when stained, unless that's what you are after.  

John

[Willyou]

It looks to me like you did not get all of the 80 grit scratch pattern removed when you moved up to the next grit (120). I can see where your sanding motions were moving across the grain in some places. I suggest that you use 100 grit in between the 80 and 120 and move your sander at a constant rate with the grain rather than in a random fashion. 150 between the 120 and 180 might also help. When you think you are ready to move to the next grit, test the surface by wiping it liberally with mineral spirits. This will highlight any rough spots that may remain. Also, be sure to vacuum and/or blow off all of the sanding dust (and grit) from the previous grit before moving on to the next finer one.

[®smpr_fi_mac®]

Hey, thanks! I'll change my approach to what you guys suggest.

I'll post up what happens this evening.

[®smpr_fi_mac®]

I spent 90 minutes going through the grits again with my ROS, following the grain direction, then with a sanding block on each grit along the grain.  Cleaned up the surface between each grit.  Then reapplied. 

Looks great. 

I did find some long scratches across the grain where I was sloppy with the sanding block so I'll need to touch those places up but it's fixed now. 

Thanks!

[Willyou]

Looks good. Good job. Thanks for showing us.

[Bill Tindall]

Other's results may differ but after decades of finishing I have concluded that it is so hard to recover from the effects of 80 grit that I just begin at 100.  Personally I think it is near impossible to successfully jump from 80 to 120, hard enough 80 to 100.  For oak I stop at 180 to avoid the risk of burnishing if I intend to stain the piece.  

I apply oil stain like French Polishing Shellac.  I make a "rubber" from a wad of absorbent cloth or wool and wrap it in a layer of Tee shirt or similar.     Something the size of a golf ball +/- is about right for a medium sized surface.  Tie off the outer wrap with a twistee.  Dip into the stain and bounce the rubber on the can lid or some such to distribute the stain in the rubber.  Then rub the stain on the wood, pressing to release stain, or not, as needed.  Finish up by wiping any excess away.  

This approach enables the stain to be applied evenly with almost no wasted stain.  A couple of ounces of stain will do a large case piece.