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How do you finish your wood?

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#1 AlienRatDog

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Posted 19 June 2019 - 09:00 PM

With Baltic birch, how is everyone finishing theirs? Anyone using a darker stain??

#2 EJN

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Posted 19 June 2019 - 09:43 PM

Paint. If it will be subject to heavy dew, paint protects it better than any clear finish

over stained wood. It might not look as good, but I look at it this way: a telescope

is not a piece of furniture.


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#3 nypsirc

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Posted 19 June 2019 - 11:42 PM

I am no furniture maker or finish carpenter so I typically stick with paint to hide those little "mistakes". 



#4 WSChurch

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Posted 19 June 2019 - 11:45 PM

Baltic birch can be blotchy if not conditioned first. It might benefit you to read these earlier CN posts concerning baltic birch: https://www.cloudyni...g-baltic-birch/


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#5 Jeff Morgan

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Posted 20 June 2019 - 12:06 AM

Another vote for paint.

 

A telescope is a working device, not furniture. Subject to lots of handling and transport. Scratches and dings are inevitable. Paint is easily fixed.

 

And paint can be "astronomically correct" - darker colors and no gloss. It can even be fun.

IMG_5006.jpg
 
But if you are an aspiring Sam Maloof: skip the stain on birch. For the best look go with spar varnish. Mixed about 50% with mineral spirits. Polyurethane finishes also look good and amber the wood somewhat. Less protection though.
 
Here is a great thread from the archives: https://www.cloudyni...4-finish-tests/


#6 stargazer193857

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Posted 20 June 2019 - 03:13 AM

Everything I read backs up what they said. Paint lasts the longest and protects more than a clear coat. Also lets you pick more colors.

Water based or acrylic has much less fumes but also is a bit less moisture resistant than oil based polyurethane.

#7 Old Rookie

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Posted 20 June 2019 - 06:15 AM

Can't do paint.  Like the warm wood color.

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#8 roscoe

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Posted 20 June 2019 - 07:39 AM

Urethane 'varnish' - oil-based, not water-based.  Staining, particularly darker color, can be blotchy - apply at least two coats to even things out.

 

I usually just put a clear finish on my astro-stuff....if I want something dark, I use darker wood, or ply with a dark veneer, unfortunately, BB only comes with a birch outer layer, so it is what it is....

 

Marine grade 'spar' urethanes, are quite water resistant, somewhat more so than standard urethanes, but even regular urethane, with three coats - a thinned prime coat, plus two full-strength coats, will survive anything but extended direct immersion just fine.

 

I avoid gloss products, they show scrapes and scuffs too easily, and make the part look like it was wrapped in plastic....


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#9 pdurk

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Posted 20 June 2019 - 07:54 AM

If you'd like to go to a darker/different color or tone in with the wood, I would look into using dyes. The pigment in dyes is smaller than stains so they don't typically end up as blotchy on woods like maple, birch, and poplar. I frequently use transtint dyes in shellac as a toner to match a finish. It's not too difficult if you have access to spraying equipment. Dyes can also be used directly on the wood, but I would work on some test pieces to figure out what you want since they tend to penetrate deeper into the material than stains. They dyes are kind of expensive, but a bottle last a very long time. You mix a few drops into water or alcohol and use that as your "stain."

 

Woodcraft link:

https://www.woodcraf...9702d3baa0025c5

 


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#10 MitchAlsup

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Posted 20 June 2019 - 12:17 PM

Tung oil, lots of tung oil.....

 

TungOil2.JPG



#11 spokeshave

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Posted 20 June 2019 - 12:39 PM

I disagree with the claims that paint is a more durable finish than any clear finish. There are very good clear finishes that are suitable for exposure to the elements. Any good spar varnish will withstand anything that outdoor imaging can throw at it as they are designed for maritime applications. so, paint it if you want to, but if you want a clear finish, use spar varnish without worry.

 

Tim


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#12 John Jarosz

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Posted 20 June 2019 - 03:41 PM

+1 for Tung oil



#13 AlienRatDog

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Posted 20 June 2019 - 04:45 PM

I was originally going to go with oil based but it dawned on me that I will be doing this with my 9 (soon to be 10 year old) daughter. We also do not have a garage. I am thinking of going with water-based. We would take over our dining room and have a window open (and exhaust fans). I would use a Minwax pre-stain conditioner (for water based), a dark water based stain, and Helsman water based Urethane (for outdoor). Does the oil based stuff have a lot of fumes?

Edited by AlienRatDog, 20 June 2019 - 04:46 PM.

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#14 rgpalmer

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Posted 20 June 2019 - 07:57 PM

+2 for Tung Oil.

 

Smooth matt finish,  waterproof,  easily patched with a little swipe of more oil, non-toxic (although not sure about possible problems for nut allergy folks).  thin the first coat 50% with citrus solvent and  let dry a few days. Lightly sand with 200 grit and then as many coats of oil as you can stand.

 

I did all the interior woodwork in my house with tung oil.


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#15 Pinbout

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Posted 20 June 2019 - 08:33 PM

I dislike the bb grain so I veneer it with better grains

 

med_gallery_106859_3508_84110.jpg


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#16 Pinbout

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Posted 20 June 2019 - 08:34 PM

even cardboard tubes veneer well

 

gallery_106859_3508_559.jpg


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#17 stargazer193857

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Posted 21 June 2019 - 05:09 AM

Tung oil sounds very easy to apply. And easy to touch up. I mean as far as skill and effort.
But wouldn't there be fumes and take longer to dry?
I read oils help with water resistance but are not as resistant as an actual hard clear coat. I read that while water based is not as resistant as oil based hard coats, it dries much faster, and no risk of long lasting smells.

My concern is avoiding finger print smudges, and making cleaning easier. I think I want satin. Also needs to withstand a few minutes of light sprinkle, or few. I'll be sure to keep it out of the rain.

#18 AlienRatDog

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Posted 21 June 2019 - 07:03 AM

There is water based spar urethane, wouldn’t that be enough protection?

#19 spokeshave

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Posted 21 June 2019 - 07:13 AM

Tung oil is the only natural hardening oil finish that has very good water and weather resistance. In fact, it is so good that it is often used as a marine finish (above the water line). There are a couple of problems with Tung oil, though. First, applying genuine Tung oil is a long and painstaking process. If you want good weather resistance, you need to apply between 5 and 10 coats - the more the better. Natural Tung oil, though, takes several days to harden (2 to 3 days) between coats. So a 10-coat finish may take a month to apply. The other problem with Tung oil is that many of the products sold as "Tung oil" are simply not - or at least they contain little Tung oil. Formby's is a good example. It is a "wiping finish" marketed as Tung oil, but it contains little if any actual Tung oil. Instead, it contains synthetic resins, aliphatic hydrocarbons, boiled linseed oil and metallic dryers. That's fine for indoor furniture finishes (though I despite the idea that they call it "Tung oil"), but it won't give you the durable, weather-resistant Tung oil finish. So, if you want a genuine Tung oil finish, you need to find 100% genuine Tung oil and be prepared to commit to a long-haul finishing schedule. 

 

Tim


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#20 roscoe

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Posted 21 June 2019 - 07:26 AM

oil finishes, penetrating oils or urethanes,  smell quite a bit more than water-based ones, and water-base dries in a couple of hours, not a day.  For inside-the-house stuff, water-base might be a good choice.  The fast dry time can be an issue if you're painting intricate things, by the time you get around the piece and back to where you started, that paint has already set up, so you have to pay attention to where that overlap is going to happen, so the transition is smooth.



#21 roscoe

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Posted 21 June 2019 - 07:27 AM

I dislike the bb grain so I veneer it with better grains

 

med_gallery_106859_3508_84110.jpg

did you veneer the edges, or just paint/stain them?



#22 rgpalmer

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Posted 21 June 2019 - 08:54 AM

Tung oil is the only natural hardening oil finish that has very good water and weather resistance. In fact, it is so good that it is often used as a marine finish (above the water line). There are a couple of problems with Tung oil, though. First, applying genuine Tung oil is a long and painstaking process. If you want good weather resistance, you need to apply between 5 and 10 coats - the more the better. Natural Tung oil, though, takes several days to harden (2 to 3 days) between coats. So a 10-coat finish may take a month to apply. The other problem with Tung oil is that many of the products sold as "Tung oil" are simply not - or at least they contain little Tung oil. Formby's is a good example. It is a "wiping finish" marketed as Tung oil, but it contains little if any actual Tung oil. Instead, it contains synthetic resins, aliphatic hydrocarbons, boiled linseed oil and metallic dryers. That's fine for indoor furniture finishes (though I despite the idea that they call it "Tung oil"), but it won't give you the durable, weather-resistant Tung oil finish. So, if you want a genuine Tung oil finish, you need to find 100% genuine Tung oil and be prepared to commit to a long-haul finishing schedule. 

 

Tim

spokeshave's comments echo my personal experience with Tung oil.  I only needed 3 coats of oil for my interior woodwork but would use many more for anything exposed to ambient temperature and humidity fluctuations such as a portable or obsy mounted scope.  Yes, not all "tung oils" are created equal.   I got mine from Rockler, 100% pure and citrus solvent to thin the first coat from The Real Milk Paint Company online.  if you do use tung oil or any oil for that matter beware of the exothermic reaction as the oil dries on old rags.  Lay the used rags outside to dry BEFORE putting in the garbage.  As an Architect I have heard of rookies on construction sites leaving oily rags and starting costly fires.



#23 rgpalmer

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Posted 21 June 2019 - 08:56 AM

as for the smell of tung oil,  smells like nuts, literally.  not a problem unless you have a nut allergy



#24 HunterofPhotons

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Posted 21 June 2019 - 10:38 AM

If I were you I would keep it simple.

Skip the stain and conditioner.  As noted above, birch doesn't stain well and I would be leery of a water-based conditioner.  Each time that you use a water-based product you're going to have to knock down the raised grain.

The water-based urethane is your easiest and safest way to go.

If this piece were destined for the Museum of Modern Art I would have a different recommendation but it's supposed to be a fun project with your daughter.

 

dan k

 

P.S.

Tung oil is not waterproof.



#25 Dale Eason

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Posted 21 June 2019 - 10:55 AM

I like MinWax PollyShades   (Pecan) combined stain and polly on real Baltic Birch.  I used 5 to 6 coats.  One coat per day.  So not really a dinning table project.  But it made a beautiful deep glossy finish that I like.  The wood grain shows through and the figure is very interesting on some of the smaller 10 inch scope.  My scopes do not stay out in the sun unless at a dark site star party and then they are covered with an astro systems scope cover.  My 16 inch scope base has been in use for many years.  Not much wood there but never needed any touch up.  Mirror box is only partially open in that pic and strong wind is blowing the foam baffle on the UTA.

 

The stain gets darker the more you apply.  So that is why I did so many coats.  It does take at least 2 coats to make a good finish.

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Edited by Dale Eason, 21 June 2019 - 11:08 AM.

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