Making a Baritone Harp Guitar

[Dave White]

Time to get the binding jig out – the top and back are routed for the depth of the binding, then the depth is increased to allow for the side purfling and the top and back re-routed stopping short at the end graft and hollow arm ends where the side purfling needs to be mitred. Using a chisel the purfling is mitred, the binding test fitted and cut to length and then the top and back purfling channels cut.



Then the English walnut binding and bwb purflings are glued in using fish glue and brown tape:






Finally the Madagascar Rosewood cap for the hollow arm peg-head is glued on:



When the glue is dry the bindings are scraped flush with a cabinet scraper:






Next the truss rod channel is routed in the neck shaft and the two way adjustable truss rod checked for fit – I’m using a Mark Blanchard designed Allied Luthierie (Electric guitar size) truss rod rather than my usual Gotoh ones:



The truss rod is glued in with a mahogany filler cap:



Then the twin carbon-fibre bar channels are routed and the bars glued in using fih glue:




A mahogany cap is glued onto the neck shaft to allow for the slanted nut and leveled with the peg-head face and the Madagascan Rosewood veneer glued on with fish glue:



The Madagascan Rosewood backstrap veneer is bent for the volute on a hot-pipe and glued on with fish glue:

[Dave White]

The pieces for the heel are glued using fish glue:



Then the mortice is routed in the body to take the fingerboard extension support of the neck:




The heel face is sanded to the correct angle and then glued to the neck shaft using fish glue:



The tennon of the neck shaft is cut and the position for the threaded inserts marked on the heel. These are drilled with an 8mm drill and the inserts screwed in – they will be epoxied in later. You can see here the result of my freehand and sometimes “eccentric” building methods in that the pre-drilled holes in the neck block ended up slightly off-centre from the final closed box. Mildly irritating but no big deal - well at least not for me:




The heel is the rough fit to the body using 120 grit sandpaper double taped to the body:



The heel is cut and rough shaped:



Now back to the “plywood” fretboard. The fret positions are marked and then cut by hand in the slotting jig:




The fretboard is cut and sanded for the taper to take the binding strips:



Next the end is cut using the circle cutting jig to match the soundhole again allowing for the binding strip:




The binding is English walnut with bwb side purflings – matching the body binding. The end strip is bent by hand on the hot-pipe and glued on using fish glue:



When the glue has tried, the ends are trimmed flush with the fretboard and the side bindings glued on using fish glue:



The fretboard is test fitted on the neck to find the correct position:



Three small wooden blocks are then spot glued with superglue on the excess edges of the neck shaft to keep the fingerboard in the correct position whilst gluing:



A small block of wood the same width as the nut is added and the fingerboard glued on using fish glue and another neck shaft of an instrument in progress used as a clamping caul as my usual one is too short for this baritone fingerboard. After half an hour I unclamped to remove the temporary wood blocks and glue squeeze-out and then re-clamped:

[Nick]

Thanks for keeping us updated Dave, fascinating stuff indeed, it's always interesting to observe how others do things.

[Dave White]

Thanks Nick,

When the glue has tried the neck shaft is trimmed flush with the fingerboard using a block plane, chisel and cabinet scraper. Then it’s into the jig and the 2mm side dot marker holes drilled:



The white plastic rod is then glued in with white pva glue and trimmed flush. Normally I wouldn’t have plastic anywhere near my guitars but I’ve found this the best material visually for this job – better than pearl or ablone – and so I’m happy to eat humble pie:



Now for the fun part – carving the neck. I use the technique I learned from Jim William’s book that involves differential calculus and drawing on facets. For me 7mm, 5.5mm and 4.5mm are the “magic numbers”. Here are the facets drawn on the neck after thinning the neck shaft to just under 21mm thick (measured from the fretboard middle:



The first facet (treble side) has been cut using my weapons of choice – spokeshave, chisel and cabinet scraper (the skew-chisel is used for the volute carving):



Here’s the treble side first facet carved:



The remaining facets are carved and then the neck bootstrapped (by the Invisible Man in this photo) using part of an old thickness sander sanding belt. I don’t use any templates but use my hands to feel up and down the neck and adjusting until it “feels” right. The guitar will be strung up and played with the neck unfinished for several days and this will result in more “fine tuning” of the neck profile before I’m finally happy and the neck gets finish applied:



The neck-heel then gets another “truing up”:





The heel is then cut in the correct position for the heel cap and veneer to match the side purfling, and two 6mm holes drilled for carbon-fibre rods to be glued in to stiffen the area:




The Madagascan Rosewood heelcap is glued to b/w/b veneer sheets using ca glue, the back edge shaped to match the binding where it joins the body, and then the cap is glued onto the heel using ca glue and when dry sanded to match the heel:




Next the fingerboard is leveled and has the radius sanded in:



Then the frets are put in – pressed using a Jaws up to the 13th fret and then the caul is taken out of the jaws and used to hammer in the rest. Each fret is seated with a bead of hot-hide glue in the fret-slot. If the fretboard has been leveled well and and the frets are pressed/hammered in with enough care – checking for high frets with a level over each group of three frets and re-pressing/hammering until they are – you can achieve a perfect fret set up without the need for fret leveling and re-crowning:



Here’s the fretted neck attached after I’d epoxied in the threaded inserts and “Fangorn” compared for size to my Grand Concert sized harp guitar:

[Kim]

Its a real treat to watch you work Dave. Everything performed with skill and confidence and such crisp clean results, we all learn a lot from you taking the time to share.

Cheers

Kim

[Nick]

Its a real treat to watch you work Dave. Everything performed with skill and confidence and such crisp clean results, we all learn a lot from you taking the time to share.

Cheers

Kim

I second that! A valuable resource for anybody that want's to attempt a harp guitar (myself included!)

[Allen]

I've been thinking harp uke, so I'm going to have to down scale everything a fair bit.

[Dave White]

Kim- thanks.

Nick - definitely have a go at a harp guitar, theyr'e great fun!!

Allen - do you mean like this one:

ferd194.jpg (111.23 KiB) Viewed 24367 times

I documented the build here on The Luthier Community Forum.

[Allen]

Could be. I've been looking at on of Pete Howlett's and am pretty impressed with the look and sound. I'll have a look at your thread and when it comes around to starting might pick your brains some.

[Dave White]

Allen,

Have a read of this article if you haven't seen it already.

[Allen]

Thanks Dave. Very interesting article.

[DarwinStrings]

Theses harp guitars like wiesies are slowly growing on me. Has anyone written a build book on them? if not I know someone who I think would do a great job of it.

Jim

[ozziebluesman]

Thanks Dave for the progress reports on the harp guitar you are currently building. It is insirational stuff! The article is very interesting too!

Jim: Here is a link to some information on Chris Knutsen.
http://www.harpguitars.net/knutsen/harpguitars.htm
He and Herman Weissenborn where the two responsible for the weissenborn guitar we know today. The weiss evolved from the harp guitar. If you are interested there is a book available here:
http://www.noeenterprises.com/
Tom Noe has been researching the weiss guitar for years. It is a great book.

As you can see I am a fan of the weissenborn guitar. It has been a fasinating story for me.

Cheers

Alan

[Corky Long]

David,

What a fantastic post - I'm mostly a lurker here - more active on OLF, but thanks to this, I'll definitely be spending more time over here.

And now, I've got a craving to start a harp guitar!! So many projects, so little time!

[Dave White]

There’s been a long gap here but I’ve had to start making a guitar that will be my sister-in-law’s 50th birthday present and her birthday is in early March. This guitar is at the “finishing” stage so now “Fangorn” can move on again at the same time. Next job is to work out where the bridge will be and what shape. I did this by taping some card on the top and marking where each of the six main strings needs to meet the centre of the saddle to intonate properly. Then I marked in the saddle position for the four sub bass strings keeping them at the same spacing as the six main strings. I can also use a pair of small magnets to check that all of the bridge-pin holes will be on the bridge-plate – always a nervous moment in making an instrument as “off-kilter” as this one but all was well.



This gives me a card template that I use to make the outline of the Madagascan Rosewood bridge:

[Dave White]

Next the bottom of the bridge is profiled to match the top’s curvature:



The bridge is thicknessed to 9mm from the top surface, the saddle slot positions marked and then routed with a 3mm bit using this jig. Two angled templates are used for strings 1-2 and 3-6 and then the sub-bass string saddle slot routed without a template:






The back edge of the bridge is then ramped on the belt sander and the string positions and bridge-pin holes for the first six strings marked, drilled using a 4mm bit and countersunk:





The bridge is then carefully positioned on the top in the correct position, clamped with a caul on the bridge-plate and the outer bridge-pin holes drilled through the top and bridge-plate:




These two bridge-pin holes are reamed a little way for two of the ebony bridge-pins to hold the bridge in place and the angle of the four sub-bass strings determined using a ruler to mark where the bridge-pin holes need to be drilled in the bridge – due to the hollow arm tuner position the angle of the strings over the saddle and bridge are slightly different from the six main strings:




The last four bridge-pin holes are then drilled and countersunk and the bridge shaped to its final shape:

[charangohabsburg]

I am following this brilliant thread since you started it. Thanks a lot for all those photos and descriptions!

When looking at your routing setup for the bridge slots I have a problem imagining how you held the bridge blank in place. Do I see a piece of sandpaper beneath the bridge blank which will hold it in place while pressure applied or am I hallucinating?

[Dave White]

Markus,

Thanks and I'm glad you are enjoying it. The bridge blank and template are held in place with double-sided tape - wonderful stuff

[Dave White]

Next the main neck tuner holes are marked and drilled. I’ve never been totally happy with the tuner layout on my multi-scale instruments so am trying something different this time. The position of the lowest string tuner is determined by interaction with those on the hollow arm. The rest of the tuners have been set to follow the offset angle patterns of the frets at the nut to draw the eye – I think it works:

[charangohabsburg]

The bridge blank and template are held in place with double-sided tape - wonderful stuff

Thanks. I couldn't see it but should have imagined.

The position of the lowest string tuner is determined by interaction with those on the hollow arm. The rest of the tuners have been set to follow the offset angle patterns of the frets at the nut [...]

The result is aesthetically very pleasing!

[Dave White]

Next job is to pore fill the back and sides using egg-white. Strips of 240 grit sandpaper are dipped into the egg-white and used to create a “wood slurry” that gets pushed into the pores working a small area at a time. This is left to dry over night and sanded back. The process needs to be repeated two or three times to completely fill the pores:



Then the pre-catalysed lacquer coats are sprayed:

[Nick]

Thanks for posting the update Dave, this thread is going to be one of those "must have" gems on this forum

[DarwinStrings]

Almost there Dave, sound clip soon, looking forward to it.

Jim

[Dave White]

Nick - Thanks. I'm really glad that you and your family made it alive and well out of that terrible earthquake. Makes what I'm doing and documenting here quite trivial and inconsequential in comparison.

Jim - watch (or listen to this space)

When the last coat of lacquer is on and sanded, the bridge is put on with the two outside pins of the main six strings, its outline carefully marked on the top with a scalpel and the finish underneath the bridge removed.



The bridge is then glued on using hot hide glue.



Tommorrow should be string up time.

[Allen]

There's some beautiful silking in that top David. I've watched every instalment you've made here. Very interesting indeed, and you've given me lots of builders ideas in ways of using up bits of wood that are just too nice to toss in the bin.