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TIPS FOR CRAFTSMEN ON THE WORKING OF IVORY Ivory is a unique material and there are methods of working it to avoid or help avoid problems. It is not necessary to use carbide tools. The material cuts well with a band saw and turns beautifully on a lathe. One should avoid temperature and humidity swings with ivory . Ivory will crack and check if the atmospheric conditions are not stable. It is best to keep ivory at a comfortable human temperature and at 40% humidity. Craftsmen should purchase a humidifier for their work area should they desire to work ivory with success in dry climates. Ivory has grain much like wood but it has the density of a soft metal. The material needs to be aged and seasoned. The material our museum sells is pre-ban ivory that is well seasoned. We also cut ivory properly - an art that is virtually gone in America today. Ivory grows in rings much like a tree and will crack and break up, over time , oftentimes in the rings it grew in , should it be improperly cut. When ivory is cut there is a great deal of waste and when it is cut properly there is a huge amount of waste. If you buy ivory from us , you can be assured it was cut properly so it will continue to age and season out in a manner that will not lead to the material breaking up over time. This is why we ask what the application of your ivory is. Ivory needs to be cut differently in accordance with the end application of that particular piece of ivory. Ivory is a pleasure to cut, drill , sand , and polish but the following information should be of help in these areas. When ivory is worked it is best to re-seal the material , especially the end grain on large pieces, to keep it from checking and cracking. Resealing can be done with a coat of Elmers' white glue set to dry or, most easily , by spraying the ivory with several coats of any lacquer or varnish. This re-sealing of the ivory is done when you plan on leaving the partially worked ivory to the side for a day or two. After the ivory is finished and polished you will no longer need to re-seal the material. If your shop has good humidity it is not so important to re-seal the ivory as you progress with your work. The smaller the ivory is, the less important re-sealing is. Piano keys are thin enough to breathe and never need any sealing . Slabs at 1/4" thick and less are pretty safe and should not need sealing. The same is true with guitar nuts and saddles , etc. but thicker knife handles, gun grips, etc. need attention in these areas. Cue inlay slabs do not need sealing but the round parts do. Ferrules are not so critical but joint stock and butt cap stock are prone to cracking and checking in a dry environment.Top-knotch cue makers re-seal the ivory during the various stages of cue production - usually by applying a thin coat of Elmers' white glue to the ivory as it spins. In the end , they work this coating off and very soon afterwards apply their finish coat to the cue and ivory. Do not use heat-lamps to help dry the finish as it will cause the ivory round stock to crack. If you do not have an atmospherically controlled workshop you may wish to work in the fair weather months when humidity is naturally high across much of the U.S. Folks living in southern States have little or no problems year-round and folks in the eastern half of the U.S. and west coast areas seldom have problems in the fair weather months. The dry western States are where folks really need a humidified shop as well as folks working ivory in the dry winter months in any area. Swings in temperature can also cause cracking especially if the swings are sudden as when one turns the heat or air-conditioning of a shop off for the night or weekend. The shaping of ivory is accomplished with saws and files. Belt and drum sanders work well but one needs to take care the ivory is not heated up too much in this work as, again , checking can occur especially on the end grain. Many folks use dremel type dental cutters to carve and shape the ivory - this is especially helpful when carving figurines and other " in the round " art. Keep ivory dry – that is – do not get ivory wet while working it. Hand sanding is best with a wet-dry type of sandpaper – use it dry. Final sanding is to be done with a used or " dead " 220X paper. When developing a buffed finish you will find a proper buffing procedure will remove all the scratches of a dead 220 sanding and leave your ivory with a mirror like surface. Polishing ivory is best done by buffing. I recommend utilizing a sewn wheel followed by a floppy wheel. A white jewelers rouge should be utilized . Small parts can be polished with small felt wheels set in a dremel or drill press. When buffing on a lathe one will find that after a final sanding the rouge can be held to the turning ivory for a melt-on application followed by a burnishing of this rouge into the ivory with a thick piece of felt held to the ivory surface. The ivory will get hot but one develops a " feel " for how hot this can get before one experiences cracking or checking. Turning and polishing on a lathe should be done at about 2500 RPM. Drilling ivory oftentimes causes cracking. Drilling small holes for knife handle rivets, etc. are not a problem but large bore drilling for items like cue joints and butt caps are. When doing large bore drilling , it is best to drill a large pilot hole prior to the final size drilling ( if and when possible and feasible). Boring bars or " gun drills " are better than standard drill bits because they do not develop as much heat. Regular drill bits can be used but one should drill short areas at a time and allow the bit to cool before re-entering the ivory. Finished ivory should be kept dry and should be kept from extended periods of direct or indirect sunlight. In the winter or dry times some folks keep a film of mineral oil on their knife handles or other finished ivory work and this is not a bad idea. Do not apply a thick coat but rather just a light film as this will keep it from cracking in the dry months. This needs to be done only for a few years after the item is made - by then the material is stable enough to not need it. Dyeing ivory can be accomplished by using any of a variety of dyestuffs. The ivory must be brought to a high polish prior to dyeing. The ivory should be " mordanted " by immersing the ivory in muriatic acid for 15 to 20 seconds prior to the immersion into the hot dye. The dye should be hot but not boiling. After removing the ivory from the dye , the color will darken a shade or two. After drying the dyed ivory and letting it cool for an hour or so then re-buff to bring up the high polish again. Be careful not to re-buff to harshly on a firm wheel ( sewn ) or the color will be buffed out of high areas. This final buffing is best done on a floppy wheel. Ageing of ivory is done through many techniques. The simplest and most commonly used technique is to polish the ivory to a high gloss and then immerse the ivory in a container of hot tea. The tea should be very hot but not boiling. The tea should have a tablespoon of white vinegar per cup of tea to serve as a mordant. Removing the ivory from the tea , one should let cool and then buff. Follow similar cautions as seen in dyeing paragraph above. Scrimshaw - the art of ivory engraving is a simple and easy to learn art form. One needs to polish the ivory to a high gloss by buffing . The ivory is then scored or scratched with a sharp needle or knife point and black india ink is applied to the surface. It takes about 30 seconds for the ink to dry and then the excess ink is wiped from the ivory with a cloth dampened with spit. Water is too watery and oils are too oily - spit works best ! I apply the ink with a q-tip and I prefer Koh-I-Noor brand ink. A good friend of mine does excellent scrimshaw and utilizes only # 16 x-acto blades ! I prefer a needle point which I fashion on the back end of a # 48 drill bit. I hold the bit in a mechanical pencil - # 48 works well as it is the same diameter as the lead for the pencil. Templates can be made from overhead projector plastic cut to shape with an x-acto blade. We hope these ivory working tips will be of help to you in your work with this beautiful material. Warther Museum P.O. Box 6 Dover, Ohio 44622-0006 Hampton Development - Commercial Web Site Development and Hosting - www.hamptonplace.com
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