Weekend Projects - Fumed and Textured Oak Bowl archive

Friday 13 February 2015

George Watkins shows how fuming and texturing techniques can be used to produce an aged effect on an oak bowl

Gallery

For this article I wanted to combine two stand alone techniques to create the appearance of an aged effect.

Sometimes when I make things, I don't want them to look perfectly smooth and polished but I also don't want them to look worn out. I hope that by using texture and the fumed oak colour, I have achieved the correct balance with this project.

In addition to the turning tools, you will also need a stainless steel wire brush for this project. The finished piece measures 230mm wide x 78mm tall.

STEP 1

Start by attaching a faceplate or screw chuck, if you prefer, to what will eventually be the top of the bowl blank. Take an oak (Quercus robur) bowl blank measuring 230 x 75mm and use a 75mm faceplate

STEP 2

With the blank securely mounted on the lathe, use a 16mm bowl gouge to remove the wax and at the same time true up the sides of the blank

STEP 3

Using the gouge in a pulling cut with the flute rolled over but not fully closed, true up the face of the blank

STEP 4

With the lathe switched off, mark out the foot dimensions. As this bowl is going to be decorative, I used 35% of the overall width for the width of the foot. If this bowl was going to be functional then you would perhaps need to increase this to 45 or 50% to add more stability in use

STEP 5

Using the 16mm bowl gouge, start to round off the corner and begin to shape the exterior of the bowl

STEP 6

With the gouge in the same orientation - as used for the pull cut earlier - hold it still and gently push in with your thumb where you want the foot to be. Once it's 6mm deep, gently pull back towards yourself to clear the wood away and then go back and increase the depth more if needed

STEP 7

Once the foot is defined, carry on and finish off the exterior shape. Ensure to stop the lathe and move the toolrest closer as the shape of the bowl progresses

STEP 8

Once the exterior shape is complete, create a recess to suit your chuck using the 16mm gouge to remove the bulk of the wood and the negative-rake scraper to clean up the edges; this will create a sharp shoulder for the chuck to seat against

Texturing

STEP 1

The four brushes which I tried, from left to right: brass, nylon, stainless steel and brass coated steel

STEP 2

Here the brushes are being tested on a piece of oak. Dust extraction is essential as texturing produces a great deal of fine dust

STEP 3

Here are the results of my mini test, from left to right: brass, nylon, stainless steel and brass coated steel. I found that the stainless steel and brass coated steel gave the best texture

Back to making the project

STEP 9

Your bowl should now be at the stage when you would normally sand and apply a finish, but you don't need to do either of these things. Instead, use a stainless steel wire brush to create the desired texture. Be sure to use the brush in a trailing motion in the safe quarter of the bowl, just as you would with sandpaper

STEP 10

Here is the texture that you should be left with after just 3-4 minutes. Do not apply any finish at this stage

STEP 11

With the exterior now complete remove the bowl from the lathe, remove the faceplate and mount the bowl into the chuck ready for hollowing. Hollow out the bowl using the 16mm bowl gouge. If you prefer to use only one gouge for the majority of your bowl work then you may have to remove the heel from the base of the bevel of the gouge to allow it to keep in contact; this will depend on the shape and size of bowl you create

STEP 12

Once the gouge work is complete and you are happy with the shape of the bowl, sand the bowl working through the grits - here I started at 120 and went through to 400. Remember to not apply any finish

STEP 13

Remove the bowl from the chuck and reverse it to remove the chuck recess. Sand this area by hand to the same grit as the interior. Here I am using a vacuum chuck but you could make a wooden jam chuck or use cole jaws, etc.

STEP 14

The bowl is now ready for the fuming process. I use household ammonia which is relatively weak at 9% but this product must still be treated with caution and respect. Wear a full-face visor and safety gloves and always do the next stages outside and away from children and pets

STEP 15

Here I am using a plastic lidded container but any container which is relatively airtight will work. To do the next stages, you need to place a piece of scrap wood in the bottom of the container for the bowl to sit on; this ensures that the bowl doesn't come into direct contact with any ammonia either by the ammonia accidentally being spilt or by condensation

STEP 16

You need to start by placing the bowl into the container

STEP 17

Next, half fill a small plastic cup with some ammonia and place it in the corner of the container

STEP 18

Here you can clearly see the set up ready for fuming

STEP 19

Next, using masking tape, seal up any gaps which may be present around the lid of the container

STEP 20

Here are the results after four hours in the container; the colour varies depending on the strength of the ammonia and depending on how long you leave it for

STEP 21

Here I am using a polywax sealer for a finish; notice how the wood darkens slightly

STEP 22

The fumed and textured oak bowl is now complete


Woodworkers Institute

Tagged In:

weekend project , George Watkins


Tools Used

16mm bowl gouge
20mm negative-rake scraper

Diagrams Click an image to enlarge

Handy Hints

1. Slow down the speed of the lathe whilst using the wire brush to add texture; this makes the brush easier to control and avoids heat build up
2. When texturing a piece, avoid using normal steel wire brushes on woods with a high tannin content, as small fragments may break off and get stuck in the grain which can then cause the appearance of black stains
3. When you are looking at the colour and thinking of stopping the fuming process, keep in mind that most finishes will darken the colour you are currently seeing on the piece
4. The fuming technique will only work on woods which have a high tannin content