How can I tell if my bridge is straight?

For a bridge to function as the luthier intended, sounding and feeling right for the player, both bridge feet should sit flat on the cello front, with even pressure on every part of the feet—so that the bridge is neither rocking back on its ‘heels’ nor forward onto its ‘toes’.

What are the benefits of a straight bridge?

As well as maximizing the life of your bridge, keeping it straight is also beneficial from a tonal point of view as the posture of the bridge makes a big difference to the sound and response of the cello. The first step whenever helping cellists to improve their set-up is to check the alignment of their bridge; it’s surprising how often this is the only issue that needs addressing. Simply straightening the bridge can return their cello to the sound and response they were worried the cello had lost.

What are the risks involved if you don’t keep the bridge straight?

It’s quite common for the top of the bridge to become warped, or bent over, if it isn’t kept straight. If your bridge has already become warped, don’t despair. Good luthiers can re-flatten moderately warped bridges (there are a variety of techniques).

Why isn’t my bridge straight?

Every time you tune (or fit) a string, some friction will occur between the bridge and string, even when the grooves are lubricated with dry soap or graphite. Depending on whether you are tuning from the pegs or fine tuners, this friction will drag the bridge fractionally in the direction of the pegs or the tailpiece.

Why lubricate the string grooves?

Lubricating the string grooves on the bridge reduces the amount of friction between the string and the bridge when you tune the string. This will also reduce the amount that the bridge is ‘dragged’ in one direction or another by the string (depending on whether you tune from the pegs or the tailpiece adjusters).

Which is the best lubricant to use?

We prefer to use dried-out soap, as it’s cleaner and
quicker to apply than soft pencil graphite. The best soap to use is of a basic quality, such as a little tablet of hard and crumbly hotel soap. Nice soaps containing oils that are good for your skin are too soft for our purpose.

If you don’t have a cake of old hotel soap, cut a 1cm slice off a bar of basic soap and put it in a warm, dry place for a few months until the soap is dried out. When you scrape the surface, small flakes should come away like snow.

A little piece of soap like this can safely be kept in your cello case and used for your string grooves in the bridge—as well as in the nut at the top of the fingerboard—whenever you fit a new string.

What’s the relative impact of tuning from the pegs or fine tuners on the tailpiece?

Fine tuners drag the bridge six times more powerfully than pegs, because they are six times closer to the bridge than the pegs.  So if you use fine tuners regularly, you need to keep a close eye on the bridge and correct its stance away from the tailpiece.

It’s worth tuning with your pegs whenever practical to counteract the effect of the fine tuners, but every time you fit a new string, you should assume that the bridge has been pulled towards the peg box and will need straightening.

How do I straighten my bridge?

Option 1. This is Robin’s preferred method, which we illustrate in the video:  Lie the cello across your lap. Wrap your hands around the strings on either side of the bridge and brace the little finger of one hand against the tailpiece and the little finger of the other against the fingerboard. If the string grooves have been lubricated, you will now be able to push the head of the bridge in the desired direction with your thumbs. The thumb that is not pushing should act as a balance or brake to ensure that the bridge doesn’t go too far.

Option 2 . The other option is to adjust the bridge when the cello is in the playing position, like this 1,000-year-old viol player from Spain: grip the bridge immediately beneath the strings in order not to break any part of it with the pressure you’re applying. Straighten the bridge gently and evenly, balancing the effort of both hands.

Why is it harder to move the bridge head towards the tailpiece than towards the pegs?

The angle of the strings down to the tailpiece is much steeper than the angle of the strings towards the pegbox. This steep angle makes it more difficult to push the bridge in this direction.

How often should I straighten my bridge?

To ensure that the bridge stays upright and in perfect condition through its lifetime, we recommend checking the posture of your bridge at least once a week and after changing strings.

Can I experiment with my bridge angle?

Some cellists carry out minor sound adjustments on their instruments by changing the angle of the bridge; other players are less keen to experiment, but we would encourage every cellist to learn how to adjust the angle of the bridge to keep it standing upright.

Practise straightening your bridge until you’re confident. Then you can experiment by moving the bridge fractionally towards the fingerboard and seeing what effect this has, then returning it to an upright position, testing again, and finally, try the bridge fractionally towards the tailpiece. When the bridge rocks onto its toes or heels, you are mimicking the effect of a minor sound post adjustment by increasing or decreasing the connection between the bridge and post.

What is a bridge gauge? 

We often cut bridge gauges for cellists once we have achieved a nice sound adjustment, so that the player has a record of the posture of the bridge when this adjustment was carried out. A bridge gauge is a piece of thin wood that is cut to fit precisely between the top of the bridge and the end of your fingerboard when the bridge is standing perfectly upright. It can be kept in the cello case and used regularly to check the bridge angle.  The video shows the gauge in action.

Where can I get a bridge gauge?

Any violin maker will be able to make you one; just make sure that your cello is playing optimally and your bridge is straight before they cut it to fit.  Use this gauge to check the posture of your bridge and correct the bridge angle as required. NB Make sure the grooves are well lubricated with dry soap before you correct the bridge angle, otherwise the strings will grip the bridge too firmly to allow any movement.

Now it’s time to watch our video to see the bridge gauge in action. https://www.aitchisoncellos.com/cellos-by-robin/video-gallery/

Huge thanks to Thibault Blanchard Dubois of Europik Music and Samara Ginsberg for their wonderful work in producing this video.
www.europikmusic.com
@samaracello