Polishing Porous Wood

tito

tito

Joined
May 30, 2006
Messages
670
I'm using the pink, no scratch rouge on my buffer to final polish out handles after sanding and treating with tung oil. If the wood is porous, the rouge fills in the pores and detracts from the finished peice. What's the best way to clean this out?

I'm headed to the garage to try acetone, alcohol, wd-40, kroil, and anything else I can think of. If anyone wants to know the results, let me know. Here's a pic of the knife, though I'm not sure you can see the issue.

thanks
 
I would try a toothbrush and the weakest solvent that will take it out. (paint thinner? alcohol?).

Prevention would be easier. Sand in your first several coats of tung oil till all pores or voids are filled. Then add a few more coats without sanding them in. The surface should be free of pores.

Rob!
 
Sand in tung oil? I guess the oil mixes with the dust and fills in the pores? I got it out with some acetone and wd-40. Have put a couple coats of gunstock wax on, and it's looking better. I'll have to experiment with the sanding. Thanks.
 
Tung oil will not fill the pores, even if you sand it in. The resin left behind by dried TO is too soft and not adhesive enough to bond sawdust to the wood. The only way I know of to fill the pores would be to use a grain filler before applying tung oil. The downside to this is that filling the pores with that product would decrease the absorption of the oil.

You are using tung oil and not tung oil finish, correct?
 
Pin holes or open grain?

Sanding tung oil WILL fill the open grain. It will take several sandings to do this. Sand with diluted tung oil because the oil becomes so tacky so quickly. Mix your tung oil about 1 to 1 tung oil to mineral spirits or even 1 part oil to 2 parts mineral spirits is okay. Sand one scale or side of handle and very lightly (VERY lightly) wipe the surface smooth. The sanding dust does indeed mix with the oil. Do your sanding in direction of grain and do your wiping against grain. That will help force the residue into grain. Wiping to forcefully will pull the oil out of the grain and all is for not. Wiping too late will allow the oil to set and make too thick a film left on surface to sand off. This does take patience since several sandings are required and the oil requires a curing time between sandings (at the very least 24 hours between and 48 hours is better). After gently wiping the wood surface will still have a thin film of dusty oil. That is okay because after all grain is finally filled level and the oil is properly cured you will then dry sand to wood surface. This method is not very good for filling pin holes. For tiny pin holes you should use another method. I use super glue - see below.

If the handle does not have a whole bunch of open or cracked grain or there are pin holes a quicker way that I use is to fill them with super glue. A tooth pick with a sharp point can be used to place a small amount on/in the pore and open grain. Let set only a couple seconds and lightly wipe smooth. The more excess glue you wipe from the surface the easier to clean after the glue sets. Super glue is very difficult to hand sand off so I usually do only a couple spots at a time and try to not leave much excess on the wood surface. Any excess will show like a sore thumb. The clear super glue will not show as clear. Within the grain and pores it will show as dark.

rlinger
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Sanding sealer can be used to fill all porous or open grained wood. It dries quickly, twenty minutes between coats. Sand after each application until you achieve the desired look. Apply your finish coat.
You can purchase this product at most any paint store.

Fred
 
I was using straight TO, but it went missing - All I could find the other day was TO finish - which is part TO and part "other fine penetrating oils." Whatever that means. So, I'm trying it out until my original can of TO turns up. Thanks for all the advice.
 
"Tung oil" and "tung oil finish" are not the same thing. Unless it is some brand I am not aware of, any "tung oil finish" will contain some amount of varnish. Certain TOFs are mixtures of oil and varnish (e.g. Minwax Tung Oil Finish). Many more, however, are simply varnish thinned with paint thinner (e.g. Formby's, Waterlox). Varnish will fill the grain, it will get tacky, and it will bind sawdust to the wood. That being said, I am of the opinion that the sawdust plays an insignificant role in the filling of the grain. I've used both varnishes and oil/varnish blends to fill the grain on walnut, elm, and oak, so it can be done, but I concur with Bob Flexner in his book Understanding Wood Finishes that the actual mechanism for finish-filled pores looks more like this:



As a side note, since pure tung oil doesn't leave an appreciable surface film, this method has never worked for me when using pure tung oil or boiled linseed oil.

I admit, rlinger may know more about this than I do, but I've never seen dried, pure tung oil that wasn't a soft, white, boogery goo, nor have I ever felt it get tacky quickly.
 
Your pix is great and a good pictorial of the total depth not being filled, which we will not be able to do by surface filling. As for my use of the word tacky, I may better have said 'sets'. That may have been more descriptive and more accurate. The sanding dust is useful as a filler which is bonded into the cured oil. The dust also thickens the solution to give it more body while working into the wood. It also adds a portion of the wood itself into the grain being filled. Of course without the dust added I believe the filled grain would look just fine but the sanding dust serves as a filling agent. Pure tung oil does not completely cure. Agents are added to assist in that. My favorite is a Waterlox tung oil product.

rlinger
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OK.....First let me say I don't know ANYTHING about knife handles but I have made custom coffee tables before and I get them level by wetting the wood and the wood swells and then drys....sand lightly...then wet again...the wood swells and drys......sand lightly again with a finer grit....eventually you'll get a glass like perfect surface.....will take time....but will be worth it.....then finish it like a regular wood handle.
 
Roosko said:
Fred...... What are you using for a finish coat ?

Robert
Click to expand...

Morning Robert,

Birchwood Casey's, TruOil cut with a flow agent like Penatrol works well.

Fred

I work exclusively with stabilized wood. It doesn't take the same finishing techniques as unstabilized wood. Very little absorption takes place with s/w, applying products that need to be absorbed by the wood don't have the desired effect.
Sanding sealer for open grained wood and super glue for pits or small inclusions will give a level surface. Burnishing the surface with a stiff piece of leather at this stage will do more for the finished look than just about anything else. This technique smooths the resin/wood surface to a glass finish.
A good discourse going on here, Fred

T-bag is rite on with his approach to finishing unstabilized wood.
 
Fred.Rowe said:
Burnishing the surface with a stiff piece of leather at this stage will do more for the finished look than just about anything else. This technique smooths the resin/wood surface to a glass finish.
Click to expand...

Whoa! Geeze, that one almost snuck by me and it sounds like a GEM!

...at what stage do you burnish? after sanding sealer?

Rob!
 
Rob! said:
Whoa! Geeze, that one almost snuck by me and it sounds like a GEM!

...at what stage do you burnish? after sanding sealer?

Rob!
Click to expand...

Morning Rob,

Yes, after the sanding sealer; if you are using that product. Even if you are not filling the wood, but are working with a non porous species, using leather to burnish the wood surface will bring out all of the features, that particular piece of wood has to offer. Use the edge of the leather first. [8 or 10 oz.] Work it briskly along the handle material. The flats of the leather, depending on the side you use will give a different effect. I always finish with the smooth side of the leather. It will bring out features in a fine piece of burl, that you did not know existed. I burnish after the finest sanding papers have been used.
This technique works well on the blade surface as well. When you think you have gotten the best finish on the blades surface, try burnishing with the leather's edge, then the flats. Those little smudges that seem to persist will many times, vanish.

I hope this helps, Fred
 
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