Sanding sealer when using oil finish

[Brianp]

Hey guys,

I've not been using a sanding sealer in recent times - I've just been oiling up my bowls with Danish or Teak oil and enjoying the warmth of their finish. Does anyone use or advise using a sanding sealer in between sanding and oiling when using oil? Am I missing a vital finishing stage?

Thanks,

Brian.

Edit: I occasionally sand after the first coat of oil's soaked in, it depends on what the finish is like.

 

[tekno.mage]

I don't use a sanding sealer when using oil finishes unless the wood is very punky and I'm using the sanding sealer to firm up the fibres soo they will cut better. Sanding sealer will prevent the oil from penetrating as far into the wood, so is usually undesirable under an oil finish.

 

[chipmunk]

Hi Brian,
Stick to what you have been doing - Don't use sanding sealer with oil.
The idea of an oil finish is to soak as far as possible into the wood and seal the pores.

Sanding sealer is designed to prevent finishes soaking into the wood and so it will prevent you from achieving a good oil finish.

Instead of using sanding sealer as Tekno.mage suggests to harden up punky wood you can also use the oil you plan to finish with - that's what I do. Even a non-drying oil will swell the fibres and make it easier to cut.

HTH
Jon

 

[Brianp]

Thanks guys, that pretty much confirms my reasoning. They say self praise is no praise, well self doubt is no doubt one of the most confounding things!

Love the oil for finish - food safe, toy safe, and very good looking.

 

[duncanh]

As posted by me in this thread from 2009

I remember going to a demo at our club given by Mark Baker (I think) where he used a sealer before an oil finish. On page 25 of his book 'Woodturning Projects' under the Surface Finishes heading he says 'Sanding sealers are used to seal and prepare the surface of the wood prior to the application of a wax or oil finish coat.
In the Oils section he doesn't mention it though.

From my recollection he said something along the lines of ...

if you apply the oil to plain wood the oil soaks into the surface (the bit between the pores) and into the pores themselves. It's easier for the oil to get into the pores so that's where most of it will disappear to and it can end up relatively deep in the timber. You can see this in action on a bowl where the oil applied to the area of end grain soaks in a lot faster and needs another application almost immediately. You can do this, wait for it to soak in again and perhaps apply again. Wipe off the excess. Then wait 24 hours, repeat, then repeat until the oil starts to build up. This may take several applications and use a fair amount of oil on a large project.

You actually want the oil to remain quite close to the surface (so that over several coats it will build up a protective layer and harden over the surface), so why waste the oil that soaks into the pores?

To stop the oil heading into the pores you can apply a sanding sealer to the surface, wipe off excess, let it harden and then sand back so the wood surface is exposed but the pores remain filled.
If you now apply oil it doesn't soak into the pores (perhaps some, but not as much) and remains to soak into the surface.

I've tried it a few times and it kind of works but I've never persevered with it.


Duncan

 

[chipmunk]

Duncan,
Well it's an interesting idea but for the sake of a wasted bit of absorbed oil it does seem a bit risky to me. More chances of a patchy finish due to variable soaking IMHO?

I tend to use either Danish oil or food-safe/mineral oil which are about as cheap as they come so for me saving a bit that gets absorbed is neither here or there to be honest. Maybe more important for the smelly oils like lemon or the like?

I also think I probably waste more oil on the brush or the kitchen towel/rag I use to apply it with, and then wipe it off with - the Danish or finishing oil that actually gets absorbed after the first coat is pretty minimal the way I seem to use it :wink:

Jon

 

[Noggsy]

I almost always use sanding sealer, cut it back and then oil (Danish, Cosmo or food safe, depending). I don't find that the oil stays on the surface especially and I find it gives a more consistent surface than just oil alone. The exception would lignam or something similarly dense, where there seems to be little point.