I would sincerely appreciate your input from those that have experience with the fuming of QWO. I have a small craftsman table which is not assembled but sanded to 120
grade / grit. I also have the ammonia (janitorial strength).
Would appreciate your expertise as to what grade of sandpaper should I go to? As well as your recommendations with respect to safety & actual fuming procedures. Best temps for Iowa climate?
FWW article recommendations are also appreciated.
As you have determined, this will be my first attempt at fuming and it is especially attractive to me as I believe the actual color would be uniform as well as penetration.
After fuming is completed, I’m planning on using General Finishes Arm R All. But again, I’m open to your input there as well.
I thank you for your considerations as well as advice,
Sincerely
Frank W Jones
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Replies
Put fuming in the search box. Many articles and videos come up.
Thank you! I’ll ch them out!
Sanding does not matter much as fuming goes well inside the wood, I sand to 150 grit and after fuming, I go around with a scotch brite to cut the raising grain. Janitorial grade will get you to a light grayish color in two hours or three depending on the wood, sap does not change color much. what darkness are you aiming for ? I do not know about the Arm R All but I believe its an oil based finish so likely to add amber tones, I prefer Enduro Var to keep he true color of fuming without much of amber .
Do your assembly and finish sanding. Fuming is a finishing process and going back to sanding or scraping after fuming is not what you want.
Build a chamber that you can really seal, then put the chamber someplace safe for when it leaks. Try to seal it well because janitor-strength will Take a while. Use a flat wide glass dish, surface area helps and some metals will react.
Set up a parallel chamber to fume samples so you don't need to vent your table to check color. I use a cooler with a hefty bag in it...but I also use anhydrous ammonia from a blueprint shop. Put in a bunch of samples so all you have to do is open, grab one, and reseal. I would check for the first time at 24hrs with janitor ammonia.
Finally (ACTUALLY FIRSTLY), get a mask with filters rated for ammonia and a pair of swim goggles that will seal to your face. The fumes will burn your eyes.
Have a 5gal bucket of water waiting to pour the ammonia into when you're done with it. The fastest way to make it safe is to massively dilute it.
The fuming can leave a cool greenish tone in the darkened oak, so an amber topcoat helps warm it to match the image in your brain.
Very helpful indeed! You mention a cool greenish tone. Will additional time yield that desirable brown color?
Thank you!
I`m new to woodworking and also building a QWO project that I`m planning to fume, but mine will be more of a cabinet.
I`m wondering about this, "Do your assembly and finish sanding."
When the doors are assembled prior to finishes, won't the edges remain unfinished where they're set into the rails/styles? With seasonal movement, won't these unfinished edges become exposed?
Fuming should be thought of as an application of color similar to staining. You don't want to go back to sanding or scraping after fuming because it does not penetrate very deeply and you can sand through to unfumed wood just like going through a stained surface.
After fuming all you want to do is apply the surface finish / topcoat of your choice.
Thank you MJ.
What you`re saying about sanding & scraping makes sense, but how do you get the surface finish/topcoat onto the edges of a raised door panel after assembly? If that center panel shrinks seasonally, will I have unfinished edges exposed?
Attached is a pic of a door in my house, that may illustrate my concern better than i`m describing. The door was painted (and caulked), the raised panel shrunk, and now there's an unpainted portion exposed.
2 ways to go:
1: Prefinish or at least partially finish your panels before assembly, including the fuming process and a topcoat at the edges. If you do that first coat with shellac it will blend when you finish the rest of the door.
2: Do your finishing at the driest time of year for your location so you are applying at maximum contraction of the panels. In the US right now you'd have to wait for next winter.
Something I have never tried is fuming oak through a coat of shellac. Next time I have an occasion to break out the ammonia I'm going to try it and see what happens. If you can fume through shellac the first coat could go in the panels before assembly. Anybody out there ever try it?
I forget the details MJ, but George Frank describes fuming an oak bank lobby after the finish was put on. Check out the book.
It might take me until next winter to be ready for finish!
:D
Thanks for the help, it's appreciated
That has not been my experience, I do fuming with strong cleaning ammonia, I only fume for between 2 and 4 hours for a light grey/greenish tone, not a dark brown, and if I need sanding some tool marks or other I do with 150 grit and the color does not change, if you cut a fumed piece even as lightly fumes as I do, you will see coloration over 1/4 deep under the surface.
I've had varied experience with the color depth. Usually I put a couple of sample blocks in the tent with the project and cut them open as a gauge. Some have had decent depth and some have not. I always go for the approach I described out of caution and treat the fuming as a "coat of color" that is not very deep.
With a more time, could one expect a medium brown color? I have some scrap pieces I could test with different time durations. This is where it gets a little queasy. I really don’t know what to expect but I guess the easy answers would be to use the scraps and experiment. I would be totally happy to replicate those Stickley colors if possible. Your suggestion about a final coating with Enduro Var is very interesting,
Thank you for the input as well as the probing.
As has been mentioned above, you need to get a more concentrated form of anhydrous ammonia. Blueprint shops used to carry this for Diazo machines, perhaps they still do. I wouldn't waste my time on cleaning strength ammonia. Tent it outside, it is very strong, you will figure it out.
Thank you! Your are absolutely correct on the anhydrous ammonia as a more concentrated form. I witnessed a hose that ruptured on an anhydrous ammonia applicator and it is very dangerous indeed. Eyes & your lungs can / will be severely damaged if you suffer exposure to this. I had planned on fuming this outside and to be upwind, even with janitorial strength.
Thank you for your contribution! Much appreciated!
I just fumed a QSWO bed with inlays of walnut and maple. Sand to your finished surface, at least 180 grit making sure any glue spots are removed etc. Fuming is part of the finishing process. You can do some touch up sanding in spots but not too much depending how deeply the ammonia has penetrated your project. Make yourself a tent of plastic sheathing which can be sealed up. I set up in my shop with great success. The wood you are fuming must not be touching the plastic or other parts in order to get a consistent look throughout your piece. If you are using janitorial ammonia (recommended) it will give good results but may take a little longer to get to the final look you want. I didn't get much of a result after just a few hours but longer did the trick. You can experiment with some scraps as far as fuming time goes or just keep an eye on the furniture piece you are fuming. Janitorial ammonia will smell really bad but you can peak in on your project with some reasonable care. I fumed my piece for two days to get the results I wanted. I let the piece stand in the open for a day after fuming to de-gas. I used several coats of Waterlox finish directly and ended up with a beautiful deep chestnut brown color. Waterlox has a wonderful tan color and provides a great looking finish.
I do this a lot. I sand to 220. I fume prior to assembly when possible, but after works too. Given the same tannin levels in the wood, you'll get darker results with warmer temps, stronger ammonia, and longer fuming times. Temp doesn't really matter but I do it above freezing. In the summer it goes quick. If it's cold out, leave it in the fumes longer. With janitorial strength in cool temps you might need it to sit in the fumes 24 to 48 hours. Finish will darken the work quite a bit. Your results will vary in terms of color depending on tannin content, even in the same piece of wood. Embrace the organic look. I get slightly different results every time but it always looks great. Here's a couple recent pieces that were fumed. All were finished with clear Danish oil, shellac, and wax. All turned out a bit different:
This is the color change I got from raw QS white oak by fuming in a simple tent with 29% ammonia which I was able to purchase from Alliance Chemical via Amazon. Topcoated w/ shellac. Very pleasing results.
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