Drilling Operations

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I decided to drill the hole for the geared 5th peg and hand taper afterwards and have done a bunch of them over the years and most were just done by "eye" so to speak without a dedicated fixture and never had a problem.  I gave away my custom modified hand reamer thinking I didn't have a need for it and ordered another one from one of the musical instrument suppliers and did notice their reamer was a lot longer than my custom one although they had modified the reamer length and had a much smaller beginning taper no doubt for some of the smaller plain traditional 5th pegs.  A few pixs below:

Prior to the above set-up, I drilled test holes in a scrap piece of walnut wood and checked the hand tapered reamer and noticed it was too small at the start of the tapered end and would require shortening to work with this 5th string geared peg and didn't see a problem with that.  After squaring up the neck in the vise and using an alignment tool in the drill press,  I drilled the hole for the geared 5th peg in small increments until I got to a little over 5/16 inch and drilled to the depth of the truss rod and all was well.  In order to cut the reamer to the length needed, I had to use a angle head grinder and after squaring off the bottom of the tapered reamer, I failed to take the time to do a test run on scrap material and did not check the diameter with my micrometer so now I had two human errors compounded and ready for a disaster to happen and it certainly did!  I rotated the tapered reamer in the hole drilled and the 5th string geared peg would literally drop into the hole.  In order to salvage this neck, I drilled the tapered hole to have straight walls and made a mahogany peg to fit the hole tightly, hand cut a few "splines" in it for air to escape from the hole and glued it in place and hopefully will not be too noticeable since I plan to move the original hole up a little over 1/16 of an inch to where the "splined" shaft will be barely touching the fingerboard binding or very close to it anyway.  I will round up another tapered reamer and I know one fine craftsman that uses a modified large file tang cut to the proper length for reaming the 5th string peg hole.  There is nothing high tech or complicated about installing a geared 5th peg but what can I say....I messed up!  Brain Dead!

I used regular metal drill bits manufactured by Greenlee of which that set is many decades old and back then were excellent quality although not the best and have added replacements to it over the years sharpening them many times;  however all drill bits are not the same.  For drill bits, you certainly do get what you pay for.  A much better drill bit type would be the brad point and not a cheap  complete set from 1/8 inch to 1/2 inch in 64ths of an inch increments that cost around 30 to 50 dollars.....they are not worth chucking in your drill press; most are not true and the diameters are not precision either.  Figure on the average of paying about 10 dollars per drill bit and that will give you an idea of something of quality.  A regular metal drill bit without a good solid fixture and a good tapered pilot hole, the drill bit will wander on you if you are not careful.  While talking about drill bits, a quality brad point point is for the serious wood worker and the Forstner type is for the amateurs and I have certainly used my share of the Forstner drill bits because they are cheaper but again, most of the time, "You get what you pay for".  As for drilling the 5th string peg hole, you are somewhat handicapped by the brad point since you don't have a lot of extra depth to deal with but there is just enough room if your brad point drill bit doesn't have a long brad point which normally is no longer than the front taper of a regular metal drill bit.  I have ordered custom brad point drill bits with a special shortened brad point for my turkey box call lids and they can get a little pricy when the diameter is over 1/2 inch but well worth the price.  I highly recommend W.L. Fuller bits and countersinks. 

After the glue dried overnight, I cut the mahogany peg fairly close to the neck with a small fret back saw and taped around the peg insert with masking tape and filed it to the radius to match the neck curvature.  I again went through the process of leveling the neck blank up and marked off the position to drill the first pilot hole for the geared 5th string peg and drilled in 1/16 inch or less increments until I had the hole at 5/16 inch in diameter.  Since I destroyed my hand tapering tool by grinding the length too short which in essence made the outside diameter oversize for the geared 5th string peg to have a "press fit",   I will have to purchase another one or improvise by grinding down an ole flathead screw driver or cut the tang off an ole file which is about the right taper or very close to it.  In all probability, I will order one although the shipping charges will be as much as the tool cost itself.   In the meantime, I will get some sanding time in on the banjo neck which is a momentous but very important task for a proper finish.  

I got another reamer in and did another test run on a scrap piece of Honduras Mahogany and my final drill hole was 21/64 inches in diameter which matched the the small end of the reamer.  I removed the button from the 5th peg shaft and drilled a 3/16 inch diameter hole in a wood block and gently tapped the 5th string peg seating it and all was well.

My neck had a 5/16 inch diameter hole predrilled in the plug that I had to install and again went through the process of squaring aka leveling the neck up in the vise and centered the hole with the drill press chuck by using a 5/16 inch diameter center punch and clamped the vise down.  I drilled a 21/64 inch hole to the depth of the truss rod and hand reamed the hole out a little at a time to be certain I did not ream the hole oversize as I did before.  The 5th string peg fit very well and will drive it to the proper depth after the neck is finished.  

The last two pixs on the far right above where I fitted and glued the bone nut blank in place.  I probably should have done more pre-shaping to the actual finish size as far as the height and taper toward the peghead but will do that after finishing and assembly. 


I believe most small shops and individuals making only a neck once in a while will drill the holes for the tuners without the aid of special made fixtures using hardened drill bushings but jigs and fixtures do tend to make it more "fail safe" and accurate.  I am not going to "reinvent" the wheel for this operation and the drilling will be totally freehand.  After laying out and marking the drill bit location with a hand center punch, I used a 25/64 inch drill bit since I plan to install a set of the Schaller D tuners and a little extra play on the 1st and 4th tuner hole want make that much difference....a little less lacquer to remove from the holes...grin if you must.


A much safer and accurate method would be to locate the center punch mark and bring the drill press brad point bit in contact with the center punch mark verifying the center and clamp the peghead to the drill press table.   The brad point bit makes a very clean hole and I would recommend a drill press speed of around 800 to 1000 rpm to prevent heating the drill bit.  The above bit was made by W.L. Fuller Company and a good quality drill bit as are all of the items they manufacture here in the USA.  The sacrifice backer board underneath the back of the peghead is necessary to prevent the exit hole from splintering/chipping.  Drilling the holes for the 1st and 4th tuners require repositioning the drill press table since the start of the hand volute taper is near those holes.  


For the side dot material I planned to use a 3/32 inch diameter plastic black rod marketed for this purpose, however after looking at the size, I immedialy didn't like the diameter and decided to go back to old school stuff drilling a hole and filling it with a black epoxy mix, although I have seen many of THE GREAT DEPRESSION ERA Mastertones with that size side dots in them.  I penciled the position of each position marker and marked two places at the 12th fret and all other position markers 1, 3, 5, 7, 10, 15, 17, 19 and 22nd has only one position dot.  I then hand drilled the holes using a tapered drill bit not much over 1/16 inch in diameter and drilled them by hand without a hand drill.  I used Stew Mac's 20-B black super glue and filled each drilled hole and will alloy to dry overnight.  I used a small scribe to help the super glue get down into the drilled hole.  When dry, I will sand flush with the fingerboard binding and hope it works as well as it use to.

I didn't like the looks of the side position dots using the black super glue and ordered a couple pieces of black plastic side dot material and will redo the above.  The black super glue didn't settle into the hole drilled and after applying another small drop, it still settled below the level of the binding.  Oh well, the old blackened Epoxy 330 worked great in the 1970s...grin if you must.


In order to use my neck shaping jig with the nut installed, I had to cut an opening in the jig to allow for the installed nut to properly clamp the neck down for the neck hanger bolts.  Prior to the actual drilling, I placed the neck heel against the pot assembly and using a 3/16 inch diameter transfer center punch referencing off the neck lag bolt holes drilled into the wood rim and tapped the transfer center punch lightly with a small fret hammer to make a witness mark on the end of the heel for the location of each hanger bolt.  I checked the diameter of the hanger bolts and they were .150 to .155 inches in diameter at the base portion of the screw threads and did a test drill on a piece of scrap end grain Honduras Mahogany and the 1/8 inch diameter pilot hole drilled was a little to tight for comfort.  I will do another test drilling using a 9/64 inch diameter bit which is around .140 inches which should be about right for the Mahogany.  It is important to keep the drill bit in the same plane as the neck heel which in this case it will be 90 degrees in reference to the portion of the neck heel that makes contact with the wood rim although the neck has a 3 degree angle.  The 10-32 hanger bolts are fairly malleable and will self-align once tension is applied from the coordinator rods but you want them as square and plumb as possible.  A good coat of Johnson's paste wax to the threads of the hanger bolts per Frank Neat does help when installing them and aids in removing them if necessary as well.  Many of THE GREAT DEPRESSION ERA Mastertones shows evidence where the factory assemblers elongated the two hanger bolt holes (North to South Direction) in the wood rim to get the banjo neck to fit the wood rim properly and a sign of a high production environment and not just on a Monday or Friday either.  The witness marks on the neck heel from the transfer center punch was not too far off center from the earlier scribed center line that I marked on the heel after I sanded the curvature for the heel.   The distance between the two hole centers was about 1.300 inches, pretty close to specifications.