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View Full Version : Another Tru-oil question - Spruce?



Pondoro
07-05-2013, 03:41 PM
I've built 4 ukes, all with cedar tops, on each of them Tru-oil looked great. The current uke has a top of lovely white spruce. I Tru-oiled it and the top now looks a bit blotchy or almost dirty. I never had this trouble with cedar, but cedar is a lot darker than spruce.

Is this normal and will it look better after a few coats? Or should I sand it off and start over?

I've kept my surroundings fairly clean - I sand and cut in my garage but apply finish in the house - does spruce demand crazy levels of cleanliness?

Thanks!

Rick Turner
07-05-2013, 03:55 PM
Shellac seal it first. You can even use the Zinnser rattle can stuff. Or seal with Smith CPES.

Pondoro
07-05-2013, 04:14 PM
Thanks a bunch Rick.

ProfChris
07-06-2013, 12:16 AM
I had the same experience using Tru-Oil direct onto spruce. The blotchiness became less marked as I addedmore coats, but it was still visible at the end. However, after a few months the colour evened out and it looks fine now.

But starting again, I'd do what Rick says. Just thought you'd like to know, if the oil goes too deep for comfortable sanding out, that time is likely to fix the problem.

aaronckeim
07-06-2013, 01:43 PM
If you aren't up for rick's good advice, I suggest that spruce can look splotchy, dirty or un-even under tru oil due to poor surface prep and extra dust from sides and bindings in the top. I suggest that the top gets it own pieces of sand paper and that you spray it off with the air compressor first. Also, the grain can sometimes raise on spruce after first coat and you may need extra sanding with 800 grit as well as the customary steel wool. the 2nd coat and beyond can also help it look more even.

Pondoro
07-06-2013, 03:16 PM
If you aren't up for rick's good advice, I suggest that spruce can look splotchy, dirty or un-even under tru oil due to poor surface prep and extra dust from sides and bindings in the top. I suggest that the top gets it own pieces of sand paper and that you spray it off with the air compressor first. Also, the grain can sometimes raise on spruce after first coat and you may need extra sanding with 800 grit as well as the customary steel wool. the 2nd coat and beyond can also help it look more even.

Aaron - I sanded the top with new sandpaper and was scrupulously clean about it. From now on I will treat spruce like a wound that might get infected, and seal it with shellac. I have enough spruce for a few more ukes, so I need to get it right.

saltytri
07-06-2013, 03:26 PM
If you use shellac or another sealer under the Tru-Oil (or any other finish for that matter) make sure that you don't sand thru the sealer to wood. While there seems to be a fair amount of variability in this area, it is probable that the finish will look different over the bare wood than over intact sealer.

Laidback1
07-06-2013, 06:45 PM
Aaron,
On the oil finishes that you guys use, Is it Waterlox, Tru-oil, some other product or proprietary and you would have to kill me if you told? I love the look of your oil finish and was wondering....
Thanks, Mark

Michael N.
07-07-2013, 01:37 AM
Spruce (actually any wood) commonly needs sanding to a finer grit when used with these thin oil finishes. The micro scratches really pop out. Much less so with Shellac. I would go to 600 G if you aren't using a Shellac sealer. You can probably get away with 180G if using Shellac alone although I go to 240G. I think I'd be tempted to give the wirewool a miss on bare Spruce.

Chris_H
07-07-2013, 03:22 AM
with any oil finish, the better your surface prep, the better the finish. Take care not to miss any scratches before moving to the next grit.

aaronckeim
07-07-2013, 05:24 AM
Laidback1- We use plain old Tru Oil, although many people don't believe us because we get pretty consistent results for such a lo tech method. It is just a result of sticking through it till you get pretty good at it. Gordon and I have done about 1400 oil finishes over about 5 years, so we are starting to get a sense of how it will behave on different kinds of wood. It has it's limitations, which Rick as some good ideas about how to work around, but it works for our shop setup, skill set and customers.

Laidback1
07-07-2013, 06:00 PM
Aaron,
Thanks for the info! Wow, Tru-Oil? I would not have guessed that. You guys do great work with it.
mark