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Brena-450
28th January 2019, 02:10 PM
Hey everyone not woodturning related really but I have this big piece of redgum I’m working on and I’m currently applying danish oil to and there is a few spots that as soon as I paint it the oil looks as if it is repelled from that area not sure if it’s absorbing it or running off but this is the 4th coat and it’s still looks like I haven’t painted this area. Any one know a solution just keep applying more until it takes?
https://uploads.tapatalk-cdn.com/20190128/255dc9a0c814f58e399999fd9ebe8d43.jpghttps://uploads.tapatalk-cdn.com/20190128/e18d0b79fa685af17be29b244152dd3e.jpghttps://uploads.tapatalk-cdn.com/20190128/07f2d59ec6067257a1a5cb88ae86d97e.jpg


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FenceFurniture
28th January 2019, 03:22 PM
Nice looking piece of timber! Would look great under strong point source spotlight of about 3200-3400°K.

It looks like it is being absorbed into more "corky" part - it's a little bit tricky to see. Maybe just put a drop or three onto those parts and watch it closely - I don't reckon it is being repelled, but absorbed straight in due to its porosity, but only you can tell which of those two is happening as you apply the oil. Dip a stick into the oil and drip it on slowly a drop at a time - practise it beforehand.

OTOH, that part in the lower left corner looks a bit weird. Almost looks like it's had wax on it (candle wax or summink?)

It may be a case of...
...just keep applying more until it takes?....in those parts. If they are softer parts you could dig them out and replace with epoxy mixed with coffee grounds but that will kinda mean starting again with sanding and finishing.

cava
29th January 2019, 02:51 AM
Hard to tell from the photographs, but has it ever had sump oil on it?

LGS
29th January 2019, 07:21 AM
Hi,
The slab looks sound and, to me, has what appear to be air pockets under the resin. Do you have course sand paper pads you can use to try and clean some of the places that look white? I wouldn't think that anymore oil is required, though a photo of the slab left alone for 24 hours may be useful. What kind of sander are you using?

Regards,

Rob

Skew ChiDAMN!!
29th January 2019, 10:37 AM
You haven't said which DO you're using, whether it be a traditional type or one of the PolyU types. Nor have you mentioned how you're applying it... these can all help diagnose the problem.

One thing you can do is put a single drop of DO in the middle of a problem area. Observe. It disappears? It's soaking in. It just sits there as a little droplet? You have surface contamination.

Apart from that...

When you applied the first coat, did you let it fully cure over several days before applying the next coat or only a few hours? If the latter, then it probably is, indeed, just soaking in. Especially if it's a 'true' Danish Oil. I'd simply put the slab aside for a week and let the DO you've already applied cure properly and seal the grain. After a week or two, I'd give the whole thing a light sand and start building up coats again.


If the first coat applied after that exhibits the same symptoms, then there's a good chance that the timber has been contaminated with something else. Looking at where the problem areas are, I'm guessing the tree may have been sprayed with something before 'twas slabbed. It's also possible that whoever milled it was a bit over-enthusiastic with the bar oil on their chainsaw. ;)

If so, I'd sand back to bear timber and wash down the surface with a solvent such as acetone or metho, being quite liberal. This will not remove any contaminants "deep" in the timber but should remove any from the surface and, perhaps, 0.2mm(ish) deep, allowing a film to flow over the whole surface.

After the solvent dries, wipe the slab down again with a rag dampened with solvent and as soon as that evaporates apply a flood coat of DO so any 'deep' contaminants don't have the time to rise back to the surface. I wouldn't bother wiping off the excess DO as one would with a traditional type, just a simple flood coat and let it cure for several days before sanding back lightly and building up the coats as per normal.