Double Bass Workshop

First though, a few words about the sticky subject of glue. The traditional glue that is used to glue basses (and all other violin family instruments) together is called granular hide glue. It is derived from the hides, hoofs and sinews of livestock, usually cow or sheep. It is a glue of antiquity and by today's standards is still amazing in strength. It is what we still use to glue and repair just about everything in the bass. The user buys it in its dry form; dry honey colored granules. It is reconstituted with water and heated to about 140° F. In its cool state it has the same consistency as stiff Jello gelatin because it basically is Jello! Jello and other gelatins are made out of pretty much the same thing (yum!) but are a little more refined and are food grade. In fact you can use plain Knox gelatine mix as a substitute for hide glue in a pinch. So now we know that this stuff is basically a meat product and not surprisingly it has about the same shelf life as meat (the dry granular form lasts indefinitely just as long as it's kept dry). When you go to the hardware store to repair an open seam on your bass and you see that bottle of liquid hide glue, you say, "aha, there's what I need." But don't be fooled. Although that is a hide glue, it is laced with preservatives and stabilizers to keep it from rotting. We have nothing against the folks who make Franklin Liquid Hide Glue or their fine product but it is decidedly NOT what you should use on your bass! The additives change its strength characteristics and make it incompatible with granular hide glue thereby contaminating the glue joint.

There are other glues that have their place in the construction and repairing of the bass, including aliphatic resin glue, the contentious cyanoacrylate glue and a few other modern wonders but the home user need not concern themselves with those. No matter what you're trying to glue, granular hide is the only glue to use with no fear of screwing something up. This is thanks in part to the fact that it's water soluble and is therefore easily removed.

Okay, now back to care guidelines:

Open seams

Generally a seam will open due to changes in humidity, temperature, weak or incorrect glue, or physical impact. You should check seams periodically, especially during seasonal weather changes. An open seam may not always be obvious. You shouldn't let an open seam sit around too long. Get it fixed sooner than later. VERY IMPORTANT: If you take it upon yourself to repair it, NEVER use anything but granular hide glue. In case you missed it, read about glues at the top of this page.

Cracks on top, back and ribs

These should be repaired as soon as possible by a luthier. The longer they're left unrepaired, the more difficult it may be to realign the crack.

Fallen sound post

Loosen strings right away! (even if you're in the middle of a gig!) Failure to due so may result in severe damage to the instrument. Have the soundpost set by your luthier.

Loose neck

If you bang the neck handling the instrument, you may have loosened it. Once the neck is loose, it's more vulnerable to loosening further, even to the point where it may break free. To check for a loose neck, loosen strings and try moving the neck side to side and back and forth. If the neck is loose, you will notice movement where the neck attaches to the body. Even more critical is the joint between the back of the neck heel and the button. If the button is partially or fully separated from the neck heel or appears to be damaged in any other way, it must be repaired as soon as possible.

Changing strings

Here's the easy and correct method. Remove the D, A and E strings, leaving the G at full tension. This should prevent the soundpost from falling. Next, string up the new E string to full tension. Now remove the old G string and string up the new G. Next string on the A and lastly, the D. Do not allow the string to bunch up between the tuning peg and peg box as this will damage the string and cause binding of the tuning gear. Always check the nut and bridge to see that the string isn't jammed in the groove. If it is, get your nut/bridge adjusted to prevent damage to your new strings. Mark the grooves of the bridge and nut with a soft (No. 1 or 2) lead pencil. This will help the strings slide in the grooves without getting damaged. After string installation is complete, check that the bridge is still straight and adjust as necessary.

The bridge

Periodically, check to see that the bridge is perpendicular to the top of the instrument. If it has moved, straighten by pushing it in the appropriate direction (it's normal for the bridge to move on its own). If it's too difficult to move under full string tension, loosen strings a little. Failure to correct a skewed bridge may result in warping of the bridge.
If the bridge gets knocked out of its proper position from handling, loosen strings enough to move bridge. Draw an imaginary line between the notches on the F holes and center the bridge feet on this line. Center strings on fingerboard for side to side alignment. If you don't feel comfortable doing this on your own, bring it to a luthier. They should be able to correct it in a few minutes.

Bridge Adjusters

You should raise and lower bridge height adjusters the same amount on each side. Either count turns or make sure that the gap between the adjuster wheel and bridge leg is equal on each side. If one side gets jacked up higher than the other, it will cause misalignment of the strings on the fingerboard and can damage the threads in the bridge and/or bend the adjuster shaft. If it's impossible to turn the adjusters by hand, don't use pliers. Loosen the strings until you can turn the adjusters by hand. I can usually remedy tight adjusters successfully if you drop your bass by. If the feet move while turning the adjusters, simply hold foot in place while making the adjustment.

Buzzing sounds from your instrument

Buzzing may be caused by a variety of problems. Open seams, incorrectly cut nut or bridge, cheap endpin, damaged strings and cracks are typical culprits. More severe problems could include loose bass bar, loose cleats or other internal parts that have become loose. This may require removal of the top. Consult your luthier.

Scratches

Minor nicks and dings are unavoidable when toting a bass around. Touch up is usually successful in correcting small blemishes. Never use any kind of paint, markers or furniture varnish to touch up your instrument. Touch-up is better left to a luthier

Cleaning of instrument

Consult your luthier for best method of cleaning your instrument. In the mean time, a soft cotton cloth or towel will do. Wipe down the top around the bridge and the strings after every session with the bow. Rosin particles that are left on the top will begin to melt onto the varnish and will require more drastic measures to remove. Do not clean your instrument using the following methods:
-steel wool
-brillo pad
-solvents such as acetone, lacquer thinner, xylene, etc. Some of these agent may work to remove stubborn rosin buildup or other problems such as tar, but they should only be used by a luthier who is experienced working with these substances.
-polishes that contain wax
-polishes that contain silicon

Strings and Fingerboard

Use denatured or isopropyl alcohol to clean strings and fingerboard. Apply alcohol to rag first. NEVER get alcohol on any varnished part of the instrument. Alcohol will damage spirit violin varnish, which is one of the most widely used types of varnish for basses. I don't recommend using an abrasive such as a Brillo pad or steel wool to clean strings. Alcohol will remove all rosin, dirt and finger oil without abrading the string. I also don't recommend applying oil, grease, talcum powder, etc. to strings. These substances will only shorten the life of the string and make a mess. If any windings on strings become damaged, replace the string. Loose windings effect the trueness of the string and can cause buzzing. Always buy the highest quality strings. Cheap strings sound bad and don't last as long as a good set.

Boiling strings (steel strings only-don't try it with gut or composite strings)

String life can be extended by boiling the strings in distilled water. Remove strings from instrument (place a heavy weight on the top to prevent sound post from falling) coil up strings and boil for 10 minutes. Take care not to get the ends of the strings in the water as they may fray. Air dry strings thoroughly, wipe off with a alcohol damp cloth and re-install.