Finishing Techniques

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John_TX
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Finishing Techniques

Post by John_TX » Thu Feb 25, 2016 12:17 pm

I'm sure there are forums dedicated to this subject matter, but would anyone here like to discuss their wood finishing techniques post-carving?
I'm struggling with mine lately but I'll share my approach to start things off:
For a V-carved sign: Apply two coats of SealCoat sanding sealer. Let dry. Apply a liberal coat of very dark stain. Let it sit in the engraved recesses, it wipes up easily from the SealCoat on the top surface if you don't wait too long. Sand the surface. Apply a lighter stain - won't affect the carved areas as they are already darker. Seal with spray-on Spar Urethane.

My struggles are with bleeding of the dark stain into surrounding wood - this would probably work better in harder wood, or I need to apply lighter coats, or simply be more patient. I'm also only guessing on which grit sandpaper to use and numerous other variables.

What techniques do you folks use? (Atonwa, your carvings are beautiful - I'm hoping you can share here too)

WillAdams
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Re: Finishing Techniques

Post by WillAdams » Thu Feb 25, 2016 1:30 pm

Finishing is an art in and of itself, but one based on chemistry principles.

It gets discussed a lot on the woodworking forums --- one of the better ones is Sawmill Creek, and I believe they have a section on this (but they're down now).

Mostly I just use spray lacquer, or mineral or olive oil and paste wax. I have tried ebonizing red oak w/ a rust-vinegar solution which worked mostly okay (but I need to work out a way to get into the grain of the wood or break down and use a wood filler/sanding sealer). See: http://lumberjocks.com/projects/75378

Your local library should have some good books on this. I've considered linking some of the public domain texts, but some of the chemicals people used to use are scary.

Perhaps this is a useful link? http://www.motherearthnews.com/diy/craf ... 5zhou.aspx
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Atonwa
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Re: Finishing Techniques

Post by Atonwa » Thu Feb 25, 2016 4:02 pm

I appreciate the compliment John. I have to say that finishing is a lot of trial and error but I'll see if I can give some suggestions.

Wood type makes the biggest impact on the finishing as you said and I actually balance the cost of the wood versus the cost of the finishing when I do carvings for profit. Sometimes you have no choice of wood for instance a customer just dropped off primary red pine siding from an 1860 Tobacco Barn to carve a sign yesterday. In this case I always ask or buy slightly more material to do some tests on for sanding sealer, stain, etc. I'll be doing some test carving this afternoon to see how soft and what tools work best and move on to finishing to see how well the sealer works.

I've also found that all sanding sealers are not created equal. The Minwax I used is just not effective against oak or pine while a Bullseye sanding sealer is. I've also taken to thinking through my steps more closely. Can I stain, apply sanding seal and then carve to provide a clean sealed edge to later stain? I tend to not stain my lettering and instead use an acrylic or sign paint. It's easy to wipe/sand and clean up later leaving very crisp edges. Once painted I can then just apply my final sealer of choice.

For your specific sign if you are forced to stay with that wood type then I would experiment with another type of sanding sealer or the steps. What if you applied the light stain and the final polyurethane finish. Then carve and fill the letters with the dark stain which should not bleed into the finished lighter face. Then apply your final finish again to the whole piece.
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atrueresistance
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Re: Finishing Techniques

Post by atrueresistance » Fri Feb 26, 2016 4:40 am

Making me rethink my plan. . . On the other side I was planning to place the rebel logo out of the remaining walnut (which is why I didn't want to go too dark)..... mmm I wonder if I can find some curly maple. The dark stain would really make the rebel symbol pop. It looks so good with the photo @Fablicator posted.
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TomDChi
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Re: Finishing Techniques

Post by TomDChi » Wed Mar 02, 2016 1:17 am

If you're interested in some in-depth information, I highly recommend "Understanding Wood Finishing" by Bob Flexner. The book covers a wide range of finish types and techniques in depth. Crucially, a lot of manufacturers of finishes don't state what's in the can. Flexner has done a lot of research into figuring out what's what and how you can figure out what's in the can, for instance by making inferences from how the directions say to thin or clean up the product.

Atonwa
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Re: Finishing Techniques

Post by Atonwa » Wed Mar 02, 2016 2:26 am

TomDChi wrote:If you're interested in some in-depth information, I highly recommend "Understanding Wood Finishing" by Bob Flexner. The book covers a wide range of finish types and techniques in depth. Crucially, a lot of manufacturers of finishes don't state what's in the can. Flexner has done a lot of research into figuring out what's what and how you can figure out what's in the can, for instance by making inferences from how the directions say to thin or clean up the product.
Thanks for the tip! Looks like his book Wood Finishing 101 is free on KindleUnlimited too if anyone has that.
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RoguePirin
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Re: Finishing Techniques

Post by RoguePirin » Wed Mar 02, 2016 2:49 pm

Atonwa wrote:
TomDChi wrote:If you're interested in some in-depth information, I highly recommend "Understanding Wood Finishing" by Bob Flexner.
Thanks for the tip! Looks like his book Wood Finishing 101 is free on KindleUnlimited too if anyone has that.
Sweet! My library has both books. Thanks for the recommendations.
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WillAdams
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Re: Finishing Techniques

Post by WillAdams » Wed Mar 02, 2016 3:07 pm

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edwan
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Re: Finishing Techniques

Post by edwan » Wed Mar 02, 2016 4:26 pm

From my experience atonwa has it right. Depending on the desired results, Sealing, a couple of finish coats, then cutting the vcarve, followed by staining the v carved letters, and then promptly wiping the stain off the finished areas works great. As atonwa pointed out, you can get lots of variations by staining/painting/sanding at different levels. You can even v carve thru transfer tape(using it as a mask) depending on your effect.

The type of wood matters a great deal not only in the cutting, but the finishing. Hardwoods like oak, cherry, maple, walnut, birch, cut well, and finish with less effort. The soft woods need more preparation, bleed a lot and get the "fuzzies" which require more sanding after cutting. Though its a matter of personal preference, I am using water soluble sealers, stains, paints and finishes. They dry fast and the cleanup is quick and easy. The newer water based finishes even have excellent life outdoors.
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