Precision clamping apparatus for sanding acoustic guitar saddles

A handheld precision clamping apparatus for sanding acoustic guitar saddles comprised of a generally rectangular base with a clamping mechanism, comprised of a clamping bar located in the base's lowest extremities, so that the low profile nature of an acoustic guitar saddle can be effectively grasped perpendicular to a separate flat sanding surface, the material to be removed from the saddle extending beyond the flat-bottom surface of the apparatus, ensuring precise material removal.

BACKGROUND OF INVENTION

1. Field of the Invention

The present invention relates generally to a system for precise sanding and more particularly to a precise sanding method for use on acoustic guitar saddles by individuals or guitar luthiers.

2. Description of the Related Art

Acoustic guitars are very popular with many musicians and individuals playing in bands, solo engagements or just for fun. In some applications, a guitar saddle must be sanded down to interface with an under-saddle pickup or to lower the strings' action for easy playing of the instrument or for changing out an existing saddle for a better material such as bone, tusk, etc. It is very important that the bottom surface of the guitar saddle is perpendicular to its sides and perfectly flat, which is critical to proper pick up function and sound. The applicant realized the need to accomplish this in a precise way.

The applicant looked for such an apparatus that would fulfill his needs. After searching the internet and trade magazines for luthier tools, no adequate apparatus was available. The most common method for removing material from the saddle is to make a pencil mark or scribe line on the saddle and remove material using a belt sander, disk sander, vise and file, or while holding the saddle in your hand moving it back and forth on a piece of sandpaper taped down to a flat surface while trying to keep the sides of the saddle at 90 degrees and maintaining equal pressure on both ends of the saddle. Ensuring accurate positioning of the saddle while sanding is very difficult, and the results only approximate. A milling machine would be very accurate, but job setup would take some time, and a milling machine can be very expensive while offering little other use to guitar makers. As a result, the applicant invented this precision clamping apparatus.

This invention will make precision guitar saddle work easy and efficient, in addition to providing a clamping method for holding the saddle secure while sanding to a precise amount. This method, which uses feeler gauges, makes this a very precision tool for saddle work.

For example, aftermarket electrical sound pickups are installed under the existing saddle and rest on the guitar body where the saddle was originally. Because the pickup has a finite thickness, in some cases 0.053″, one would need to remove 0.053″ from the bottom of the saddle to maintain the guitar's playing characteristics, or action. Using the aforementioned methods is a very time consuming task, and, with the exception of using a milling machine, holding these tolerances is near impossible. The risk of removing too little or too much material from the saddle is very probable, and the end result is having to start over with a new saddle, creating additional costs and loss of time for the individual or repair shop.

BRIEF SUMMARY OF THE INVENTION

In one embodiment of the present invention, the precision clamping apparatus, employing a clamping bar for holding the saddle in place during sanding, includes an aluminum base with an L-shaped slot for both accepting the saddle and holding the clamping bar; a clamping bar held in place by a roll pin on either end; two clamping bar screws to hold the saddle during sanding; a set of replaceable stainless steel shoes which simultaneously provide superior durability as a sanding surface and also secure the clamping bar in its slot; and a push pin for seating the saddle to an underlying flat surface.

DETAILED DESCRIPTION OF THE INVENTION

The preferred embodiment of the precision clamping apparatus10of the present invention will now be described with reference toFIGS. 1-6.

Referring toFIG. 1, a preferred embodiment of the precision clamping apparatus10is comprised of a base12; clamping bar16; roll pins18for holding clamping bar in place; internal clamping face40; shoes14, which are replaceable after excessive wear; socket cap clamping screws22, preferably #8-32×¾″ 304 stainless steel, for tightening clamping bar16; and pushpin20. Preferably, the base10is made of aluminum 6061, approximately 1.5″×1.5″×3.25″ in size, although other sizes and materials may be utilized. The clamping bar16fits in the horizontal leg of the L-shaped slot in base12, allowing clamping bar16to move freely from front to back. Preferably, the clamping bar is made of ¼″×¼″×3.58″ stainless steel key stock. A ball plunger38secures pushpin20in its storage hole when pushpin is not in use.

Referring toFIG. 2, a full view of push pin20is shown, preferably measuring 0.062″ in diameter and approximately 1.38″ in length and with a knurled knob on top. Preferably, the push pin20is made of CRES 300 series stainless steel.

Referring toFIG. 3, the shoes14are preferably 0.672″×3.25″×0.063″ in size and made of CRES 300 series half-hard or full-hard stainless steel, although other hard materials may be utilized. The shoes14are secured with screws24, preferably 18-8 stainless steel 100 degree flat head Phillips machine screws, 4-40 thread, ⅜″ length. In a preferred embodiment, the right and left side of the clamping bar16will be kept in place using two roll pins on either end, preferably 1/16″×½″ stainless steel. Also, the bottom side of the clamping bar is held in place by the front side shoe.

Referring toFIG. 4, a guitar saddle28is shown clamped in the precision clamping apparatus. Push pin20is shown in its storage position.

As shown inFIG. 6, a preferred embodiment of the precision clamping apparatus10is shown resting upon two equivalent stacks of feeler gauges34in order to set the amount of saddle material to be removed equal to the height of the feeler gauge stacks.

The sum of these parts that make up the preferred embodiments of the precision clamping apparatus function in unison with the feeler gauges and flat sanding surface.

The following is representative of the process employed when using the precision clamping apparatus10according to a preferred embodiment:1. After determining the amount needed to be removed from guitar saddle28, create two stacks of feeler gauges34of equivalent height as shown inFIG. 6. When installing a Fishman Matrix Pickup, for example, to maintain current action on a guitar, remove 0.053″ from the bottom of the saddle per manufacturer's instructions by making two stacks of feeler gauges 0.053″ each as shown inFIG. 6, set on a flat surface, preferably a 12″×12″ granite plate.2. To insert saddle as shown inFIG. 4, turn base12so that clamping screws22face downward in order to prevent saddle from dropping below clamping bar. Slide saddle into slot so that bottom of saddle is flush with shoes and finger-tighten clamping screws.3. As shown inFIG. 6, set precision clamping apparatus10on feeler gauge stacks34, each stack 0.053″ in height, so that the shoes14rest upon the feeler gauges.4. Loosen socket cap screws22so that saddle drops onto flat surface, preferably a 12″×12″ granite plate. While holding the precision clamping apparatus10firmly down on feeler gauge stacks, use index finger to push down on push pin20to seat saddle down on flat plate.5. Use appropriate hex wrench to re-tighten socket cap screws22firmly so that only that portion of material to be removed from saddle28, in this case 0.053″, extends beyond shoes14as shown inFIG. 6. Pushpin20can now be stored as shown inFIGS. 3-5in storage hole36as shown inFIG. 2.6. Referring toFIG. 5, if removing more than 0.018″, first remove the bulk of the material off the bottom of the saddle28using the optional shoe guard plate26and electric rotary tool30with drum sander attachment32. Otherwise, proceed to the next step.7. The saddle is now ready for the final sanding procedure. Tape a sheet of sandpaper to a flat surface (preferably a 9″×11″ sheet of 150 grit silicon carbide affixed to a 12″×12″ granite plate as was used to support the feeler gauge stacks34). Holding the precision clamping apparatus10in your hand, sand the bottom of the saddle until no more material can be removed. You are now finished. For example, if you are installing a Fishman Matrix pick up, you will have uniformly removed precisely 0.053″ from the bottom of the saddle.

The total process takes about 5 minutes.

When using the precision clamping apparatus10, the individual or guitar luthier will be able to take precise amounts off the bottom of a guitar saddle while avoiding mistakes and eliminating the need for extraordinary skills. In some applications, such as crafting one's own saddle, a pencil line or scribed line may be preferred and the feeler gauges will be unnecessary. For this method, the saddle can be installed in the precision clamping apparatus10finger-tight, and the mark on the saddle can be lined up with the bottom of the back shoe14.

The foregoing disclosure and description of the invention are illustrative and explanatory thereof, and various changes in the size, shape and materials, as well as in the details of the illustrated construction, may be made without departing from the spirit of the invention. The present embodiment is, therefore, to be considered as merely illustrative and not restrictive, the scope of the invention being indicated by the claims rather than the foregoing description, and all changes which come within the meaning and range of equivalence of the claims are therefore intended to be embraced therein.