Steffen Nowak, Maker of fine Violins, Violas and Cellos in baroque and modern style
BVMA Technical workshop: The use of equisetum arvense, the common horsetail
Occasional I am asked about an article I had written some years ago for the BVMA newsletter issue 50 (2007)
Steffen Nowak, Bristol, January 2020
My first encounter with horsetail was way back at the Welsh School of Violin Making (WSVM) in 1983/84 during our weekly sessions with Harp maker Alan Shires teaching us tool making. Being a novice to woodturning I struggled to get a nice finish to some turned handles and someone suggested the use of horsetail, commonly known as shaving grass.
I have actually never found a really ‘sharp’ horsetail growing in the UK, but have been successful in South Germany, Italy and Spain. I also bought a nice bunch once at a London flower shop (imported from Holland) and Kremer also supplies it ready cut in stems. Once you have a cutting horsetail the stems should have as large a diameter as possible as they shrink when dry and the following preparation might be too difficult.
Initially I used the cut segments – split open and with light pressure motion over the finished wood wherever I thought it needed ‘rubbing down’.
A few steps to guide you through the process will make it even easier:
Rub off any side stems if still present.
Now cut off the hard nodules at the end of each segment.
With a scalpel blade slice open each segment lengthwise.
Using a curved scraper scrape out the inner translucent membrane.
Depending on how many segments you are preparing, to prevent the scraped ones from drying out too much and curling up you might want to put them back into water.
Now dry all the rectangular pieces on several layers of kitchen paper, pressed down gently with some suitable pieces of wood.
You might need to replace the paper layers once to get them really dry.
Image 5. .
Once dry use a strong wide masking tape (or experiment with other tape varieties) and put each flat horsetail segment on the sticky tape side and press down gently.
I have used them as a gentle abrasive on both spruce and maple. I tend to use it more one directional with light pressure rather then going in circles. The light abrasion possible with horsetail appears to have more of a cutting then tearing action on the wood fibres. If used more aggressively it will give a more pronounced appearance to the medullary rays of spruce. Once the piece becomes clogged up with dust this can be easily brushed out with an old toothbrush and reused till it loses its bite or breaks up. Generally, use it lightly rather than forcing it.
Where and when to use horsetail (if at all) is a matter of each makers individual approach. Any surface finish on the white wood should already be an integral part of the varnishing process. What you do to the wood surface will have a major impact on how the wood will react to any possible ground sealer, the subsequent varnish coats and of course its optical appearance.
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