Danish oil "seeping/weeping" in spots through black walnut

[MikeAndSon]

My son and I are total novices. We are finishing a slab of black walnut for coffee table, and on advice, we started the process with Danish oil (watco).For 3 coats, it took the oil unevenly and did not start to develop a sheen. But we did notice a little of what I now I understand is a "seeping" or "weeping" prob. Little spots of oil seep up through the wood after wiping, even into the next day. We would wipe away as we saw them. then after a couple days, we poured on a 4th coat and let it sit longer before wiping. Finally started to get a little sheen to half the slab. But now there was more regular seeping problem. Every day there were new drops coming up through wood. You can see small circles like faint "stain" spots all over the surface from where these drops are coming through. We waited SIX days from last coat, no more weeping, and then sanded wood with 220 paper to see if it would remove the small circles. It did partially, but now more oil is seeping out again after the sanding. We are not sure what we need to do but don't want to apply any other finish till oil is done coming out, and it seems there's still a lot of oil in it.

[Von]

I'm not sure this is relevant since it's about pure oils and not Danish, but Marc did a video recently on applying oils that touched on similar issues: https://www.youtube.com/watch?v=OLW9f9Dw5Gg

 

[wtnhighlander]

Danish oil is a unique critter. My preference is to flood it on, wet sand with #600, then wipe away the excess. Dry overnight, repeat. It never builds a sheen this way, but develops a buttery-smooth luster that is very sensual to the touch. 

Being of high oil content, I guess the weeping issue can be trouble if you over-saturate the first coat, but I've only ever experienced that with pure oils. I'd suggest wiping it down once or twice a day with mineral spirits, to remove the weeps, but it sounds like you have it under control.

[MikeAndSon]

On 6/7/2023 at 8:05 PM, Von said:

I'm not sure this is relevant since it's about pure oils and not Danish, but Marc did a video recently on applying oils that touched on similar issues: https://www.youtube.com/watch?v=OLW9f9Dw5Gg

 

Thank you - I think it's very relevant. He does show a sample with a finish that is part oil, part solvent, like Danish oil. We did flood rather than putting on thin coat -- exactly how we were advised -- and this is exactly what I feared - the wood inside must be too saturated. The question is, what next? He shows a piece of oak that has uncured oil in it 2 months after application. Does this mean we are done with this slab for two months? I guess there's no do-over at this point. Would heating or blow drying it cause it to express oil and maybe accelerate the curing process?

[MikeAndSon]

On 6/7/2023 at 8:28 PM, wtnhighlander said:

Danish oil is a unique critter. My preference is to flood it on, wet sand with #600, then wipe away the excess. Dry overnight, repeat. It never builds a sheen this way, but develops a buttery-smooth luster that is very sensual to the touch. 

Being of high oil content, I guess the weeping issue can be trouble if you over-saturate the first coat, but I've only ever experienced that with pure oils. I'd suggest wiping it down once or twice a day with mineral spirits, to remove the weeps, but it sounds like you have it under control.

Thanks for reply. I just watched video sent by Von - interesting; video recommends thin application rather than flooding. It looks like we must have oversaturated. Video also shows wood that stays uncured for two months after flooding method. so I am worried now that we have a very long wait before this oil cures.. We should have wet sanded - we are too new to this - but at this point I'm too concerned about applying any more oil. I'm wondering if using a hot blowdryer would accelerate the curing process by causing it to express some of the over saturation faster, or if that could damage the wood.

[Coop]

Is this slab end grain or long grain?

[wtnhighlander]

I don't know if a hot air gun could heat evenly enough, but storing the slab in a warm place, like an attic,would probably accelerate the curing. Still takes days, though.

[gee-dub]

The only way I have had long term success with weeping is to just keep wiping.  One of my first attempts with using the flooding method with oils led to a small table becoming a resident of my guest bathroom for about 2 months before I could actually put it into service. The good news is that table is still in use to this day.  One thing for sure is that if you do not continue to wipe away the weeping, the wet portions of finish will eventually cure into bits of goo.  This will lead you to a re-finishing effort that you do not want. DAMHIKT.

[MikeAndSon]

On 6/8/2023 at 9:49 AM, gee-dub said:

The only way I have had long term success with weeping is to just keep wiping.  One of my first attempts with using the flooding method with oils led to a small table becoming a resident of my guest bathroom for about 2 months before I could actually put it into service. The good news is that table is still in use to this day.  One thing for sure is that if you do not continue to wipe away the weeping, the wet portions of finish will eventually cure into bits of goo.  This will lead you to a re-finishing effort that you do not want. DAMHIKT.

Thanks Gee-dub. We are not home most of day but are wiping away spots as they appear and we see them. Right now there are faintly visible circles, that you can only see in the right light. I'm wondering if these can be sanded off.

[MikeAndSon]

On 6/8/2023 at 6:44 AM, wtnhighlander said:

I don't know if a hot air gun could heat evenly enough, but storing the slab in a warm place, like an attic,would probably accelerate the curing. Still takes days, though.

 

On 6/8/2023 at 6:44 AM, wtnhighlander said:

I don't know if a hot air gun could heat evenly enough, but storing the slab in a warm place, like an attic,would probably accelerate the curing. Still takes days, though.

That's helpful - we do have an attic that would work well for it. Nice, practical suggestion.

 

[MikeAndSon]

On 6/7/2023 at 11:32 PM, Coop said:

Is this slab end grain or long grain?

Slab is long grain. (if I understand question correctly - I'm not totally sure I do). the seeping is occurring on the long grain/face.

[gee-dub]

Continuing to wipe away the wet spots as they appear should be fine.

On 6/8/2023 at 8:02 AM, MikeAndSon said:

 I'm wondering if these can be sanded off.

I would be tempted to rub them as hard as I could to try to blend them in.  If the finish has reached the point where it can no longer be blended with a rag then adding a drop or two of finish (or some mineral spirits) to some 600 - 800 grit wet/dry abrasive and feathering things in should serve you well.