"Brushed and Burnt" Oak Flooring

Thoughts on how to replicate a "brushed and burned" look on wide plank oak flooring, using a flame gun and a brushing power tool. July 27, 2008

I have a job that has some wide oak floorboards that I need to match in with. They have had a technique applied to them known as brush and burn. As far as I know this means that they have been first burnt with a blowtorch and then wire brushed. However, I have no specific info on how exactly to do this, such as what type of wire brush to use, hand/drill driven etc. I was wondering if anyone could offer any advice on this technique?

Forum Responses
(Architectural Woodworking Forum)
From contributor R:
We do it a lot. We have one of those wide flame torches for doing shrink wrap covering like they do on boats. You could use the wand type for weeds you hook up to a propane tank. We have several options on the brush but the cheapest to start with a Makita brush tool from Timberwolf Tools. It comes with the 100 grit nylon brush and I'd recommend you get the steel brush as well and do some samples to see what the customer wants. You could make and arbor and stack a bunch of brushes on a homemade arbore and put it on a drill. You can put some bearings on a pipe for an outboard handle. Higher speed is better than 500 rpm. Been there and done all that.

From the original questioner:
I'll give it a go. I assume you burn the wood before brushing? Does the brushing then not get rid of some of the burning effect? Do you in that case do another burn after the brushing?

Not sure I can stretch to the Makita for this job, although it does look the tool for the job. Will try the drill method you mentioned. What are the best brushes to get? Nylon ones I wouldn't have thought would be hard enough to pick out the grain in oak, although I may be wrong. Steel brushes, on the other hand, sound a little too harsh. Brass maybe?

From contributor R:
You are going to have to do your own tests. The nylon brushes have an abrasive in the bristles. I don't think brass will work very well. The nylon is good for softer material and will do things to hardwood as well. Buy a bunch of different types of steel diameter bristle brushes. Burn it first.

We just do stuff because we know very few folks have done it before so there's really no one to ask. Start playing with chemical, brushes and keep a record of what you did with samples. Don't be afraid to try anything. Don't expect many folks to even share "secret techniques". Nobody told us how to do it.

From contributor D:
About how many linear feet will a set of those nylon brushes cover before you have to replace them?

From contributor R:
I couldn't even begin to guess. I am in charge of purchasing and keeping the shop running. If I could get the guys in the shop to keep track of that stuff it would be a miracle. Plus each guy handles it differently so wear can vary and wide versus narrow is a whole different issue. We are a total custom shop that does projects with fuming, brushing, adze finishing and footworn floors. We've done 4,000 linear strip flooring that was handplaned of antique oak or 3,000 square feet of reproduced footworn flooring.

Like I said just go out and do it and keep your own records. Experimenting costs but it's the cost of doing business and if you can do what no one else can you will get more business as you figure out how to price it so you don't lose your shirt.

From the original questioner:
As you say, I think that experimentation is the best way to go. I'll give it a try and see what the results are like. I have already had some reasonable success with fuming by spraying a strong ammonia solution onto hand-worked ceiling beams etc.

From contributor R:
The more you say the more I get a feel for your experience. Get an angle grinder and some different steel brushes of varying bristle diameter and do samples and carefully record what you did and how long. Do it with different woods and make sure you do enough extra pieces so you can play with the next step.

The best results with fuming are to actually seal up a chamber. Spraying it on isn't really effective. We use a hundred lb tank of anhydrous ammonia. Before that we used blueprint ammonia in a sealed chamber overnight. This was timbers, millwork. An interior we would seal it off and let the fumes work overnight. It's highly corrosive and will rust and corrode metal. Better to fume before the install.

From the original questioner:
Yes, I will try the angle grinder with some different brushes. The only problem I foresee is that most of the wheel brushes are quite narrow so it will take a very long time to do a lot of floorboards. A cup brush may work but it won't be working along the grain in quite the same way as the Makita you suggested so I don't know what the results will be like.

As for the fuming, yes I have heard that the best technique is to use the ammonia fumes in a sealed area. However, a lot of the work I have done is with retrofitted ceiling beam layouts into houses that are being lived in. Not sure whether I'd fancy releasing a load of ammonia fumes in that situation - I might kill the occupants and they wouldn't be able to pay me. Spraying it on in advance does seem to have a reasonable result (although perhaps not as good as the proper way of doing it). The oak goes a lovely walnut shell brown color and it is a lot more even than a stain.