Please read all instructions before proceeding. If you are not familiar with the following terms or procedures, please find a violin maker, qualified instructor or knowledgeable sales person that can assist you. A moment of consultation can help avoid making your instrument unplayable.
Old bridges can be brittle and can crack easily. Always have a spare bridge and new strings on hand in case they are needed. These instructions apply to Violin, Fiddle, Viola, Cello and Upright or Double Bass.
Check that your sound post is in the proper position. If you are unsure of how to do this, find a knowledgeable and qualified person that can help you before proceeding.
Look to see if the bridge feet are lined up with the small f notches in the f holes.
If it is necessary to reposition the bridge feet, carefully place the Violin, Viola or Fiddle in your lap with the peg box by your knees. Cello and Bass players should place the instrument in a stand, or have someone carefully hold it in the upright position while you face the instrument.
Firmly grasp the Violin, Viola or Fiddle bridge feet with the thumb and first finger at the bottom on both sides of the bridge. Cello and Bass players should try to fit as many fingers on the bridge feet as you easily can.
Applying gently increasing pressure, move the bridge feet in-line with the f notches in the f holes (see first image).
Cello and Bass players may need to move one foot at a time.
It may be necessary to slightly loosen the strings to get the feet to move easily. If you have to loosen the strings, wait to re-tune your instrument.
Check to make sure your bridge is perpendicular to the instrument body top. Holding the instrument so you can see across the top, look between the bridge and tail piece. Check to see if the back of the bridge appears to be straight up and down in relation to the instrument top just behind the bridge (see image below). If your bridge is straight and properly positioned you can re-tune at this point. Proceed to the next step if you need to adjust the top of your bridge.
To adjust your Violin, Viola or Fiddle bridge top, firmly grasp the top of the bridge with your thumbs and first fingers on both sides of the bridge just under the strings, (see image below). Cello and Bass players should use as many fingers as possible.
Applying gently increasing pressure, move the bridge top until the back of the bridge is straight up and down in relation to the body top just behind the bridge area, (see image above). Take care to not move the bridge feet during this process.
A slight forward or backward lean to the bridge can alter the string vibrating length. A violin maker would measure the scale or string length and make sure the top of the bridge is the correct distance from the fingerboard side of the nut.
If you can not get your bridge to be perpendicular to the instrument top, take it to a violin maker and have them take a look.
Once the Violin, Viola, Fiddle, Cello or upright Bass bridge is in the proper position, re-tune your instrument. Check to make sure the bridge stayed in the proper position during the re-tuning process. Readjust if necessary.