hamsguitaringblog

Building the Basses

Last summer while working on the previous build, “Maple-ene” I opened a message from a long time friend which included a link to a short video about a guitar builder, Randy at Wyn guitars. What an impressive story. The number of instruments he builds is staggering, at least to me. Randy builds basses, very beautiful and unique basses. I was immediately sure that after “Maple-ene”, a bass would be my next project.

Well, not one but two basses right? It’s the only way around deciding on 4 string or 5 string. For the woods I chose solid cherry for the 5 and a three piece body of Cherry/Walnut/Cherry for the 4. The tops are bookmatched Flamed Maple and Locust.

While sawing, shaping, routing and gluing the tops to the bodies I spent a lot of time searching for hardware, pickups, electronics etc. I settled in on Hip shot Quarter Pound bridge for each, Seymour Duncan PJ set up with 250k pots, Gotoh tuners and Grover strap locks. Long scale: 34 inches.

I had previously routed for wiring channel and some chambers for weight reduction but until I make a full scale drawing I can’t locate the pickup cavities, control cavities or bridge location. By making the full-scale drawing I’ll be able to locate the pickups to the bridge and scale length to achieve the correct string spacing at the pickups. I made a template for each of the four pickup cavities. In the end the string spacing on all came out well.

Armed with dimensions for pickup and control cavities and ready to rout I also have to calculate the neck and pickup planes on the body as with solid body archtops. Once these angles are done I rout the cavities and locate the bridges. I used a laminated neck design with Maple and Sapele, just a straightforward ‘set’ neck with huge tuning machines.

Finally I get down to wood finish and have decided to use polyeurethane except for the Rosewood headplates will have to be lacquered, or at least not anything with oil such as the poly. Usually with oily woods like Rosewood the poly will never dry properly.

These two finished up really nice, I enjoyed it and learned a lot and now it’s time to put on some Allman Brothers and play along.

The Oblique journey or The Building of Maple-ene

Long ago there came to me from the west coast supplier, along with other items a set of Maple back and sides for a Dreadnought . Recently the time seemed right and I finally got on with building the Maple guitar I had wanted to build for a long time, since well before the Maple set was purchased.

It’s been said, by me, that I have the ‘Build of Dreams” philosophy. Meaning I build instruments as a hobby. I build them for someone. I don’t know who that someone is yet. When I build it, they will come.

I had set my mind to use a two step dye process with red over black. At some point after getting the back halves glued and the sides bent I had a vision of something a little on the dark side. As I list the parts and hardware I’ll need the personality of the instrument emerges. It starts with necessary things like, bridge, bridge pins, end pin, strap button, position markers, tuners and either natural or bleached bone nut and saddle. With this build I got hung up on making my own position markers from MOP. What I came up with was a small Oblique triangle. I also chose to use Maple throughout, almost, and name her ‘Maple-ene’.

Having started on the MOP position markers I also embarked on a hunt for a MOP rosette. Not really hard to find except for the size I need, which meant special order, normally two weeks only thing, it’s coming from Vietnam, Tet starts in one week and the factory will close for three weeks, so I said “make that two”. One decision I really sweated over was to make the end cap the way it’s done with MOP. Still not sure if it flies but I like it. I have the top thicknessed, braces roughed and just waiting, waiting waiting. Three months after ordering the rosettes arrive. Once the rosette is in I cut the sound hole, glue on braces. Carving braces and voicing the top is next then, make the box.

Maple-ene is mostly Maple. Back and sides, back center strip, binding, bridge, fretboard, headplate, and parts of the neck. I am trying to keep the flame going, ha ha, on the surface, with the red over black it looks a little “hellish” to me. There is something inside hiding in the same skin as the outside. I mentioned dark earlier, right? The first unconventional thing I did was cut that Obtuse angle on the headstock. Some one out there will tell you that headstock looks short and stupid. Well, when they look down and see the bridge they’ll flip! That was the second unconventional thing I did. It was well thought out and I calculated the footprint or square inch gluing surface, it’s almost the same as a standard Martin bridge. I’m happy with the way the bridge turned out.

The third unconventional thing I did was float the fretboard over the top. It’s really not much above the top and is ‘glued’ in so it will not flex. Two reasons, no more planing the fingerboard to compensate angle drop created naturally when an angled neck meets a flat top. Secondly there is nothing to dictate having the fingerboard on the top of a dreadnought other than tradition. Many builders and factory guitars are made this way today. Archtop guitars and mandolins for instance also float the fingerboard over the top.

I always finish up the build process by stringing up the instrument and doing a preliminary set up to get dialed in real close before final sanding and lacquer. This one came together very well, played like an old friend sounded awesome.

The Oblique triangle, having no right angle and therefore being unable to make a square, is like our world today, things are off, including me.

It’s been way too busy here to explain why I took so long to get this posted. So, a wrap up is in order. This one is done and in it’s case “waiting for love”. RIP Nanci.

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The Skinny Grape

This is a story about a piece of Ambrosia Maple and some purple and black dye. The piece of Ambrosia Maple, a term I hadn’t heard, was purchased by my wife at Guitar show a couple of years ago. While attending our booth this gentleman appeared from nowhere with this dazzling piece of Maple. What a wild piece of wood.

Since the board was barely a half inch thick I decided on a flat top, with a set neck at 2.5 degrees. I rounded the edge of the top and created the illusion of an arch top by rolling the top from the lower bout to the waist and then shaped a subtle forearm and belly bevel.

The body is figured Sapele with two full veneer layers, one of Maple and one of Mahogany. The body is chambered in the bass side of the lower bout and also both areas of the upper bout. The total thickness is 1& 7/16ths inches.

I used flame Maple fingerboard and headplate veneer along with a two piece Cherry neck. Sperzel locking tuners, Schaller wrap around bridge and those sweet, sweet Lollar Pickups.

The thing is simply awesome. My friend Patton came down to try it out and was impressed with the clarity over the volume range and when playing softly then striking a note. Very crisp and lots of depth.

I wanted something different in the build this time around and believe I found it. See more of this guitar at http://hamjonesguitars.com/jimmie-grape.html

On November 16^th, this Guitar spent a day in a recording studio with it’s prospective buyer so he may be sold!

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In January 2020 I began building two dreadnoughts, Cherry and Rosewood. I have finished the Cherry and written about it in my previous post and now it’s time to write about the Indian Rosewood build.

As mentioned before I have implemented some changes in my building process intended to reduce the weight and add to the resonance and volume from the box. As discussed in the previous post, I had formed some bad habits and made a few ‘heavy’ guitars, or overbuilt them. The first one turned out great. Lets see how this one did.

This Rosewood is a lot more dense and heavier than the Cherry was. I have sanded the sides and back down to the same thickness as the Cherry and it is considerably heavier at this point. I used the same Spruce/Sapele laminated tail and heel blocks here as well. While getting my parts made and nearing assembly I continue to weigh parts and groups of parts to keep track of the total weight. I have tried to make the Cherry and this guitar as identical as possible and yet the Rosewood one has come out a few ounces heavier. The Cherry was 4lb 7oz while the Rosewood was 4lb 10oz.

In the end both guitars turned out great and much improved to the ear above the ‘overbuilt’ guitars, which by the way are discounted on the website

hamjonesguitars.com under Acoustics.

I got some straight advice from those folks at the a fore-mentioned retail shop and it was very positive for me in the end. The four overbuilt guitars had a few things in common which I saw no problem with until I started to find out where the excess weight was. On these guitars I used the same board for the heel and tail blocks which, when I dug around the shop for a piece I realized it was like lead. I also used a thicker fingerboard requiring a similarly thick bridge. Also, I had left the heel of the necks fat for some reason and probably should have sanded the back and sides thinner. All these little things added up enough to make a difference. Remember to keep the weight down.

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Hard to believe it’s been nine months since I last had a finished instrument to write about. I actually started two dreadnoughts in January 2020 with intentions of taking my time in order to implement some improvements. The two new builds, one with a Indian Rosewood back and sides and one with Cherry back and sides are done. The former is a good buffing away from being finished and the latter is done and will be the subject of this writing.

The Cherry back and side set came out of a board I picked up from a local sawmill/lumber yard which has since, disappointingly, closed. This board was 8 1/4’s x 16” x 80”, 17 plus board feet, rough sawn all sides. I have gotten a lot of use from this piece of lumber for other instruments and necks as well.

I mentioned before that changes were in store for my future acoustic instruments.

The story behind this is simple. I took some instruments to a guitar retailer with a unique inventory of handmade guitars. I went for an evaluation and I got one. It was an odd visit as in, they forgot I was coming to an appointment only shop and the owner spent very little time with me once he arrived. The person who did see me and played a couple of my instruments was very pleasant and seemed to enjoy what he saw. The owner however was rushed, because now his next appointment is waiting, curt and somewhat unpleasant about whatever issues he thought I should address in my building. I did however rise above it all get some legitimate and reliable feedback which I have used to make the improvements. The simple part, overbuilt. I had not carefully noted the weight of the parts and the whole throughout the build. I had used some Sapele for heel and tail blocks that were very dense and ‘heaavyy’. I was using a thicker fingerboard, which required a thicker bridge and last my heels were fat and heavy. I had no argument, in fact I sort of knew after building a few mandolins per Roger Siminoff’s method. There is a lot of discussion on the web on the subject of just exactly how much your F5 should weigh. There were four of these overbuilt guitars which I have worked on to reduce the size of the heels and take some weight out. Check them out at

hamjonesguitars.com for photos and special pricing.

This guitar has American Cherry back, sides and neck, a Spruce top and American Ebony fretboard. The sides for this guitar had been sawn and clamped between two flat boards for almost 4 years prior to bending. The back was more recently sawn from a piece which was set aside back then as well. The sides and back thicknessed to about .110” and I’m using tail and heel blocks made from laminated stock of Mahogany and Spruce. The blocks came out weighing about half the weight of the old Sapele blocks. The fretboard on this guitar is made from Persimmon/ American Ebony. Next I fashioned all of my braces about 1/16” thinner and worked the top bracing as usual only going a little further to lighten it up a little more. The tops on my guitars were fine in the Gen I as the evenness of tone has always stood out, but they were a little stiff. The fingerboard issue was easy enough to fix by making it and the bridge thinner.

With the body together, the other area to make changes is in the heel carve of the neck. I just had to discipline myself to keep digging and get the heels to proper size. I weighed all parts as I went and weighed the finished body and neck before assembly.

Fiinal weight on this one: 4lb. Including hardware, 3lb. 8oz. without.

The average weight of the overbuilt guitars was 5lb. 8oz with hardware. I was surprised there was as much difference in weight. As for the sound? The output is louder, the tone is still very even and the string sensitivity is increased See it and shop at hamjonesguitars.com

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January 2020

During the Holidays we found out that one of the items on Bob’s list was a Ukulele. Christmas came and went with no Ukulele but seems Bob has a birthday soon. So I found kits on sale and ordered a Soprano kit from Stew-mac. The top is solid Mahogany, the back and sides are laminated Mahogany. Nice looking pieces of wood and all the parts.

First step is to build the ‘mold’ for gluing the sides, top and bottom while maintaining proper shape of the instrument. It uses one piece of wood, four L brackets, two wood blocks and two pieces of dowel. The specs and video are all available at their web site so I will not go into great detail on that.

It’s always good to gather all of the parts and build in the brain so one has a vision of how things go together. I have built a lot of instruments but never a Ukulele so I study it well.

It’s a two part project basically. The body and the completed neck. The body is assembled after gluing braces to the top and back. Take note that the braces for the back have a radius so do not clamp on a flat surface. When it’s together and sanded it’s ready for the neck. The completed neck would be finished, headplate & logo (not included in the kit), fretboard, frets, side markers, installed and everything sanded and ready for assembly. As mentioned the kit did not include a headplate. Since the fingerboard provided is Walnut I found a nice piece in the shop with a cool arch in the grain to use as headplate. The kit maker did not intend for the added thickness of the headplate so I do not recommend trying it unless you use a veneer about 1/32”

Up to this point things have gone smoothly. Assembly of the body, braces, top and back come together easily for proper fit. The neck shaft, fret slots, and frets all came together well also. But when preparing to fit the neck to the body and drill the dowel holes I ran into some trouble. The arc machined on the neck shaft which mates to the curve of the body at the heel, is not concentric to the center-line of the neck shaft. I shaded the face of the neck side with pencil and used a spindle sander with 2” drum to remove material. I got lucky. A couple of passes, a little hand sanding with some PSA 150 grit on the body, I cleaned it up to a proper fit. Drilling the dowel holes by hand was tricky but can be done with a little caution.

The instructions called for locating the bridge, before gluing the neck to body, by dry fitting the neck in place. I totally disagree. Locate the bridge after the neck is glued into place, it’s more accurate.

With the fingerboard taped off I just rubbed in several coats of lacquer on the neck being careful not to get lacquer on the gluing surface. When it was dry I buffed it out and glued the neck to the body. I must stress that the neck angle is critical to obtaining proper string height. Use the neck reset calculator at Stew-mac to figure this out and get it right.

Next thing is to install the nut and locate the bridge. Once the bridge area is taped off I apply finish to the the body and buff it out.

Gluing the bridge was also tricky. I had a hard time finding the right clamp, in-fact I had to modify one, and getting a caul inside that small body was a challenge.

In the end it turned out great and my son in law loved it.

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In the process of sorting lumber for fall and winter builds I came across two pieces of Cherry that looked like they were destined to be a lap steel and that was it. This will be my second lap steel and I had so much fun building and noodling on the first one, I’m excited to get started.

I started by joining the two pieces and cutting the design on the bandsaw. Next I finalize my design: laying out the bridge, pickup, controls, jack and nut locations. From the nut location I can layout the headplate then cut away the excess on the bandsaw, freehand. The top and back of the headplate need to be sanded before laying out it’s shape and tuner hole locations. When the layout is done I can saw the shape of the headplate on the bandsaw and drill the tuner holes. On the first lap steel I placed the control cavity on the back with a cover. This time I decided the top mount the controls to avoid having the cover and screws on the players thigh. Now I can rout the pickup and control cavity and drill the jack mount hole. The body itself is now ready for lots of sanding prior to adding the finger board and hardware.

The next few steps are: building the fretboard, headplate veneer with logo, pickup ring, control cover and nut. I’ve chosen figured hard Maple for these pieces it will make a nice contrast to the Cherry Red I’m aiming for on the body. Starting with the fretboard, cut to length, width and thickness. For fret markers I make a .060” slot and super glue a piece of ‘wbw’ purfling and for the position markers I’m using black plastic dots. The headplate veneer, pickup ring and control cover are made from a Maple about 1/8”and final sanded around 7/64″. It’s tedious but the Maple doesn’t break easily which helps. Final part to make is the nut which I’m making from cold-rolled steel, ¼” x ½” When these parts are finished I’ll do a final layout, drill holes for the bridge, pickup ring, control cover, and jack plate. I’ll temporarily mount my hardware and remove it before lacquer and buffing which helps not to damage the finish, as in no drilling after buffing.

When the lacquer has been sprayed and it’s surface sanded and buffed to a gloss finish I can put this pup together and plug it in.

It’s all done and it works and after setting up the string height at he bridge and setting the intonation it sounds great. You can see this and many other fine hand crafted instruments at

hamjonesguitars.com

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Lilly & Walter

One evening after dinner in the fall of 2018, my wife said, “I would like to get rid grandma’s Cedar Chest,” a chest that had been handed down, was beaten, ugly and had block nailed to one rear corner where a foot had departed years ago. I replied that I had no suggestions but I would think about it. Next day, having forgotten all about it, Kat asks, “Could you make me a guitar from grandma Lilly’s Cedar Chest?”

So I set about drawing pictures, surveying the chest, taking it apart and sawing the chunks into workable blanks and began building a guitar. The chest was made of Cedar planks of various widths and lengths and therefore not applicable for an acoustic guitar. The design I came up with was a product of Kat telling me what she liked and she chose the wood blanks which made the body. The final plan is a solid body Archtop with dual humbuckers. She will have a Cherry neck, Rosewood fingerboard and bone nut.

I start by sawing out the body shape and sanding the edges to size. Now I use the plane routing jig and create the neck and pickup angle planes. Though the body shape is different from other models I have built, I am still able to use the same layout template for the neck pocket, pickup cavities and the hardware mounting holes. When the routing is done there is plenty of final carving and sanding the top. Next step is binding, then more sanding. At this point the body is ready for the neck.

The neck is made of Cherry with a two-way truss rod, Rosewood headplate veneer with logo and MOP inlay. I’ve already checked my tenon fit prior to attaching the fretboard and just need to final check and/or adjust befor gluing. It’s very important to…. Nope it’s imperative to check the bridge location before gluing. Just to be safe. Now it’s just a matter of sanding and sanding and sanding and getting it all smooth and clean for lacquer.

So the other side to the story is Walter, Grandpa Walter. There was plenty of “Frankenwood” left around so I made Walter from my design. He is a Fender style with dual humbuckers and double cutaway with streaks of gold.

I’m pleased with how these turned out. Another great idea from Kat, the marketing dept.

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Much too far back in time I began building a second Ham Jones Archtop Mandolin with Walnut back and sides, a Red Spruce top, plus a Flattop Mandolin with figured Sapele back and sides, Spruce top. It was January , and I should’ve had these finished mid-April but life gets in the way of things at times and here we are almost mid-July telling the tale.

I’ll start with the Archtop which I have built and covered here before. This one was made with the same piece of Walnut as the first. Since I’ve posted this type build before I’m just gonna cover the basic plan and any things I did different. This time around the bending went a little better with experience and the rim came together without issue. I decided it was best to have the top on before sawing the neck pocket so at this point I moved on to carving the top and back plates.

Carving the plates by hand with convex finger planes takes a lot of time but if I want to say ‘hand-made’…. Right? I start with a large flat hand plane to knock the outer edge down, cut the shape out at about an eight inch over size and begin carving. The upper surface of the top is carved first and then the inner. On the inner side I do use a drill press jig to drill a series of holes to facilitate wood removal. When the top is ready it is glued in place and the edge is trimmed flush to the sides once the glue is dry. At this point I finish carving the backplate and make and install the two tone bars for the top.

I made the neck, finger board, headplate, and frets same as before except I built the fingerboard extension into the shaft and eliminated the extra part. When the neck is finished, including fingerboard and fret work I can move on to fitting the neck joint.

I am not going go into detail about fitting the neck but it goes like this, I slip the finished neck into the pocket and let it go where it wants to go. Now check, the fret plane height at the bridge location, the center line of neck is center line of body, and fretboard is 90* to sides of body. If it looks good then I got lucky, if not I adjust.

With the neck glued in and locked, the back plate can be installed, trimmed and final carved along with the top. Before routing the binding slots there is sanding required to get the top and back flush with the rim for a nice clean channel. After the binding is glued in there is lots and lots of sanding.

Prep for lacquer includes some grain filler, especially with rosewood headplate. I really don’t like to use grain filler unless it’s necessary. If I didn’t say it already, lots of sanding, this time with fine grit paper. I start with 100 grit after binding, then 220, 320 and 400 then 600 to 1000. After lacquer there is more sanding, gently with 400, do not to remove all sparkle, then with wet sand with 600, 1000, 1500 as needed. Then buffing and polishing.

For about a year I’ve had it in my head that I wanted to build a Flat top Mandolin. Not having built one before and this being a prototype I used the same mold as for the Archtop and build the rim, using figured Sapele this time.

From the same Sapele I made the back halves and joined them using a redwood center strip. I braced the back similar to guitar bracing with a spine and three ribs. It looks to me as if the bracing is too heavy but when done, the weight of the finished instrument was the same as the Archtop, for whatever that’s worth.

For the top I’m using Ukulele size Sitka Spruce with ‘H’ bracing which looks heavy to me, same as I felt about the back bracing. I have at the time of this writing strung it up and I am pleased with the sound. I calculated the size for the circular aperture and after the two top halves were glued I installed the rosette. Next I position the rim to the top and mark the bracing layout. When the braces are glued in place they can be carved, tapered at the ends and then locked into the rim.

The neck joint on this is done the same way but there is some adjustment needed to get the correct neck to body angle due to the lack of an arch. Once the finished neck is fitted to the pocket the neck can be glued in place. The back is positioned and it’s braces locked into the rim then glued in place. What follows is lots of sanding, binding installation, lots more sanding, more sanding then the finish and hardware.

Now I have two new Mandolins ‘Windy’ and ‘Skinny. They both play and sound great, of course.

See these and all the other fine instruments for sale at hamjonesguitars.com

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A Note For Beginning Guitarists

I often wonder, if every guitar purchased was properly set up, how many more guitarists there would be, and how many fewer guitars would be hanging in pawn shops. Getting beyond the initial soreness of the fingertips on the fretting hand is most likely the number one cause of attrition among beginners and 100% preventable.

Guitars come in all shapes, sizes, styles, materials and construction techniques. This is great and lends to the lure and romanticism we have for our instruments. The crux of this biscuit however is that if the thing isn’t playable, then it becomes a wall hanger or firewood. Unless your able to wrestle the music from a hard to play guitar.

The key elements are; the Fretboard/Neck, Frets, Nut and saddle. The key measurements are; individual string height at the first fret and twelfth fret, and neck relief and intonation.  The techniques used and measurements desired can be found online and I will include some links as well.

Once your guitar is strung and tuned we will begin by measuring the neck relief.  Have the guitar vertical to the bench, (gravity), and  depress the sixth string at the first and fourteenth frets, (use a capo at first fret).  Check the height at the seventh fret and record it. (writing down these measurements will aid in understanding the process and intent). The neck relief measurement should be .008” to .012”, if less than .008” a truss rod adjustment could be necessary, especially if you hear string rattle, (depending on playing style), if over .012” a truss rod adjustment would be necessary for lower action. To adjust turn (normally), clockwise to tighten which will flatten the upbow in the neck and reduce your measurement. I’ve seen this done with the strings tuned vs. loosened. Safer to de-tune, relieving tension, turn the truss rod a quarter turn or so then re-tune and re-measure. Do this gently and in small increments and recheck until you get the correct measurement.  I recommend you recheck the neck relief in at around two weeks, after the guitar has settled in from the adjustment. Now check  string height of each string at the first fret using a feeler gauge set of your choice. ( a note on feeler gauge: a longer angled blade works well for me. Short blade gauges make it difficult to reach center strings. I’d stay away from gimmick tools made for this. A feeler gauge is best.) When making initial measurements write them down.  I have the guitar flat for the first fret measurements and the hold it vertical again to check the height at the twelfth fret. 

We set the distance between the bottom of the string and the top of the first fret. These measurements will vary between types of guitars, electric vs. acoustic vs. classical, bass, etc. and personal opinion. On acoustics I aim for .024” on strings 5&6, .018” on strings 4&5, .011” on strings 1&2. If your measurement is higher than your target you will have to remove material from the nut slot in order to lower the string. This is normally done with a fret slotting file, or you can improvise one edge of the appropriate thickness of feeler gauge blade. Do this by filing ‘teeth’ in the edge of the feeler blade. It is certainly ok to stack the feeler gauges to get the desired thickness for measuring. As for the actually cutting I would recommend slotting files. Buy the ones you need. The slot should be wide enough to let the string lay on the bottom and move back and forth freely. Once your are removing material from the slot let the fear sink in. The fear of going too deep.. then you’re screwed. Seriously, I am  always very cautious, using just 2 to 4 strokes of cut before  resetting the string, bringing it up to pitch and measuring only to have to loosen it, remove it from the slot, and file 2 to 4 more strokes. This is very tedious work and should be approached with calm reserve. I can assure you that one does not want to ruin a nut and have to start over. Measure, loosen string and move aside, cut the slot, replace the string, tune the string, measure, repeat, repeat, repeat.  If you are making  a new nut, compare your measurements each time and count the strokes of your file to learn how much you are cutting. Do this consistently for better results.

Congratulations, you’re string heights at the first fret are correct and it’s time for the easy part. Adjusting the string height at the twelfth fret. On acoustics you will generally have to loosen all strings enough to remove the saddle and remove material from the bottom to ‘lower it’ . On electrics there are a variety of bridge/saddle styles, but generally the adjustment is simply turning a screw or screws. The target measurement here can vary also and can be more of a ‘feel’ adjustment than a hard number. Either way if your first fret heights are correct the next step is to re-measure the string heights at the twelfth fret. Now subtract your twelfth fret target from your current measurement. Double this number. The answer is the amount of material you will need to remove from the bottom of your saddle or lower the saddle(s) on an electric. Yes! It’s geometry. Since twelfth fret is the center point between the nut and the saddle that’s where we measure. Therefore, in order to lower the string 0.010” at the twelfth fret, requires lowering the saddle height 0.020”. The target height I start with here is .093″ E string 6^th, .078″ at E string 1^st, on acoustics. My personal set up is .080 at sixth string and .068 first string. Depending on the integrity of the fretboard, neck relief and playing style lower numbers can be achieved without buzzing. Striving for this magic lowest action is easily done on an electric guitar because if you get the saddle too low, simply raise the saddle back up. On an acoustic if you go too far it’s not that simple. The saddle of an acoustic flat top guitar should be flat on the bottom and have an arc on the top which matches that of the fret board. Most archtop acoustic guitars have a thumbscrew adjustment similar to electric guitars. On acoustic saddles you can always put a ‘hard’ shim beneath the saddle to raise it up. Apply super glue to the bottom of the short saddle and firmly place it onto a rectangular piece of shim material about a 1/16 “ wider and longer than the saddle. When it dries trim the excess. Assuming you’re .010” to low, use a .020 to ,030 thick shim and remove the material from the bottom for proper height.

http://www.guitarnotes.com/notes/noteget.cgi?basic_guitar_setup