Cedar slab furring / dark spots

Hi guys,

I thought I would start this new thread as Im now a little unsure about what is going on with my table.
As some of you may know I thought have furred the finish on my table but i am a little confused as to whats actually going on.
I will post some close up pictures later but dont have a camera right now.

I dry sanded this table back to about 800 - 1200 ( cant remember) grit with an orbital sander.
I then applied by brush a liberal coating of feast watson furniture oil.

Everything looked fine except in some areas, (most notably the tighter knotty patches) the timber went very dark and felt a little furry.

I have since sanded it back with the same sandpaper (800 - 1200) and the stain began to remove from the normal areas but the darker patches remained.
I then dropped grits back further and further but the dark patches still remain and I am at the point where I think I need to strip it all to bare timber to get beneath the dark patches to start again.
So, even though the dark patches are not furry any longer, they are still very dark and matty feeling compared to the rest of the table.

Am i on the right track? By sanding further? Or is the dark patch simply now the colour from the oil?

The original finish had no dark patches.Attachment 453324

I will try and post some closeups pictures later
Ben

I'm tipping it's just the grain absorbing the oil differently; where the grain reverses it can start to be more like endgrain and suck up more oil than the rest of the slab.

There's nothing you can do about it short of sanding it all back totally and putting on a synthetic finish that is just a surface coating, rather than a finish that gets absorbed, and even then you'll probably still have some variation in colour.

I agree with ElanJacobs. The dark spots are always going to look dark, due to the fact that the grain is in different directions.

Rob

Different types of grain will behave differently with finishes. Your table being a crotch section will have everything - straight grain, interlocked grain, reversing grain. Essentially on the same plane, you'll have parts that behave like side grain and end grain. The darker spots are the 'end grain' taking up more of the finish than the surrounding areas. You can alleviate this a bit by sanding these areas to a higher grit. You can also try using a grain filler and sanding sealer first, then applying your finish.

What everyone above has said and also going on the post in another thread of the dining table, I’d lay money on it originally having a tinted finish which was either a poly or lacquer type rather than an oil finish of which will bring out the natural differences in the timber regardless of what the grain is doing, but yes endgrain will go darker with oil, of which your particular slab will have a fair bit of.

Okay, this is starting to make sense.
Gee, and I thought this was going to be a simple sand and oil :)

So, I have found evidence underneath of what looks like stain that has overlapped the edges. It also looks like it had a waterbased gloss coating on it. (From my limited experience)
So the initial finish was combining a darker stain and the synthetic coating that sits on top ---> therefore the darker end grain bits wouldnt have shown through and a more consistent colour resulted.

So going forward, I need to -
1) completely sand back. Any suggestions on what grit to use last before applying the finish?
2) Choose a synthetic coating instead of an oil.

As i dont fully understand what a synthetic coating is, do I just go for a water based gloss or semi gloss polyurethane finishes such as Cabots Cabothane Clear? (Which I have some leftover)
Or decide to choose one with a stain in it?
Or do you guys have other suggestions about which synthetic coating would be best for this situation?
I saw someone in another post suggested a wattyl estapol 2 pack finish.... or is that going a bit far?

Thank you all so much, as removing the dark spots was/is taking some some significant sanding, I feel like I was on the road to destroying the table!

Ben


Attachment 453362

Attachment 453363

If you really want a flat, even colour, yes you’ll have to sand off the areas with oil soaked in to the grain before using a polyurethane (the oil could be quite deep?) on the other hand many of us deliberately use oil to accentuate the grain patterns and pay more for timber with those grain patterns, you could think about embracing those patterns and the way they will shimmer as you move around the table.