Wood for bridges

[dsouthwood]

I am using a white wood bridge on my erhu, and I like the brighter sound it gives. I would like to carve a white wood bridge for my zhonghu to see how that sounds. So my question is, what kind of wood is white wood? What do I ask for at the hardwoods store? And while I'm shopping, are there other woods it would be worth trying?

Thanks,

Dennis

[calden]

Dennis:

Where are you buying the wood? I am assuming it'll be at a place like Woodcraft or a similar type place that can help you select stuff. A local place that sells to luthiers woudl be excellent.

Maple - good and hard and would a first choice to try, used in violin bridges

Cherry - fairly hard, worth a try

pine, fir - very soft, probably would absorb and muffle the sound, but worth a try

cedar - can be white, also soft, usually used solely for soundboards

oak, ash - probably absorb sound, smells bad when sanding or working

beech - might work okay

basswood (linden, limewood) -interesting wood, technically a hardwood but is soft and almost totally without grain, used for carving. Probably too soft but would be interesting to try

Let us know what you discover. As long as you've got the carving knives out and have already knicked up your fingers, I wouldn't hesitate to try some synthetic materials, too. I'm thinking maybe epoxy resin, or that stuff used for kitchen countertops - Corazine, Coriander, Carioke, something like that....

Carlos

[davidmdahl]

My zhonghu was dramatically improved with a white wood bridge. I have no idea what kind of wood it is, sorry to say. Since other aspects of a bridge besides material seem to affect the sound, it is hard to know from one bridge to another what are the critical factors.

Good luck with the carving, Dennis. That sounds like fun.

Best wishes,

David

[dsouthwood]

I'm wondering if the density of the wood rather than hardness would be the important characteristic. Here are two density charts I found on the Web:

www.engineeringtoolbox.com/wood-density-d_40.html

www.simetric.co.uk/si_wood.htm

There's a place in San Diego that sells hardwood for hobbyists, and I remember that they have a scrap bin which is where I would do my shopping. I feel an experiment coming on.

Dennis

[calden]

Dennis:

If you're experimenting, go ahead and try some exotic woods like koa, zebrawood, ebony, etc. They all have different densities and properties that would affect sound production. Song sells a little package of different bridges to try. I was surprised at the sound differences.

Carlos

[song]

Hi Dennis,

Yes maple is a good choice. Some Erhu players here specially look for broken cello of double bass bridges to carve Erhu bridges out of them.

You probably would be interested to know that there's a guy on another erhu forum that diy some bridges out of ebony, boxwood and old rosewood and posted his analysis.


Merry Christmas to all!


Sung Wah

[dsouthwood]

I'm gearing up for my zhonghu bridge carving project. I have gone shopping at the Rockler woodworking supply place and bought the following woods, in order of density (kilograms per cubic meter):

Walnut (700)
Cherry (900)
African Blackwood (1250)
Lignum Vitae (1370)

African Blackwood is extensively used for clarinets, oboes, bagpipe chanters, etc. because of its tonal properties, so that is what I will start with. Unfortunately, the references I found say that tungsten carbide tools are required for working it. We'll see how my Dremel does.

The cherry and walnut are available in 3-foot lengths of doweling, so that will minimize the carving, but the other two are available only in turning blanks, which have a square cross section. The bridge on my zhonghu measures 11/16" in diameter, so I got 3/4" diameter doweling for the cherry and walnut, and 3/4" square pen turning blanks for the others.

I'm starting to collect social security next week and will have lots of time on my hands, so I'm counting on this to keep me busy. I will, of course, keep y'all posted.

Dennis

[jetz320]

very interesting to hear. i thought that you were going to try out maple wood also? i think i might also do something like this. is there a wood that can melow the sound a bit?

[dsouthwood]

I may also try maple wood. I'm wondering what would create a more mellow sound. Softer wood? Maybe softer wood would not transmit the vibrations as cleanly to the snakeskin. Maybe heavier wood would dampen the vibrations the way a mute does. Those are the things I am hoping to find out.

I still don't know what kind of wood "white wood" is. Does anyone on the forum know? And does anybody know what kind of wood the ordinary hardwood doweling you find in hardware stores is?

Dennis

[calden]

Dennis:

Doweling comes in different varieties, usuallly only hardwood because of the stability. Oak is what I've seen a lot of. Just ask 'em what it is. Don't know what "white wood" is - could be anything, really - oak, maple, poplar, probably not pine if it's referenced to making musical instruments.

Song's collection of bridges is interesting. THere is one that is reddish and lighter and softer than the dark, hard, heavy bridge, but the sound is louder and less refined. Ya never know. Have fun and do let us know.

Carlos