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ihasmario
17-09-2014, 05:14 PM
8-)

Here's going to be a build diary of a large lever harp. Expect slow progress. I am posting it now (before building has begun) because I am planning the harp myself and because I am having trouble sourcing timber, but I am currently in chats with some people.

I say "scratch" because chances are I won't be doing the shaping of the big pieces of wood, because my tools are very bad for large projects like this. I also definitely won't be doing the soundboard myself.

If the timber becomes too hard to source, I may just be building a harp from precut parts. If anyone would like to help me, where is a good place to get large pieces of hardwood (Cherry, Walnut, Blackwood, etc) in Western Australia? The dimensions I need (excluding soundboard at this stage) are;
1x 4.25cm, 36.20cm, 75cm
1x 4.25cm, 11.5cm, 130cm
2x 2cm, 18.25, 127cm

Where I think the planks are going is outlined in green. Not sure of what kind of sizes are economical and if glue will be strong enough compared to solid chunks + dowels, so I am just guessing as to the plank layout so far. Lots of work and reading to be done.

The only possibly hardwoods I can find at hardware shops are poplar and red cedar, which are ok but I'd prefer something more common for use in harps since I am not sure how well those woods would go (haven't done any maths at this stage).

Depending on the wood and progress, expect a dingotone finish or something similar, 34 strings (C-A, C being red on the diagram), height around 1.5m.

Here's the basic technical drawing, except some modifications and designs to make it a bit more unique. The reported sizes are tentative and are not indicative of what will be built.

Good luck to me :)
http://www.pitbullguitars.com/wp-content/uploads/2014/09/b6mc3-Harpplan.png

dingobass
17-09-2014, 09:50 PM
Over to you, Gavmiester! O Acoustic one ;)

ihasmario
17-09-2014, 10:03 PM
Going to leave the acoustic parts until last. The neck and pillar are going to be done and assembled first, which are the tension bearing parts (along with the soundboard - eek).

The soundboard, I will probably use "aircraft birch plywood" - since I am having trouble finding a large enough piece of plywood, let alone a large enough piece of spruce (and having enough money for it). I think I will probably shrink the harp a little to suit local sizes (2440mm length for the plywood). Aircraft birch seems like a pretty common soundboard material for non-pedal harps.

I actually think that overall a lever harp is an easier build than an acoustic guitar in terms of materials, since the soundbox is square and I have no idea how to bend wood. Cutting out the rounded parts is just a matter of having the tools. There's a lot more on guitars that I don't have any ideas how to build from scratch. There are quite a few harp 'kits' out there - but they become less economical since most of them are outside of Perth and the shipping cost is a killer.

I'll probably do an unstrung miniature harp before getting to this big one, but the big one is the goal.

dingobass
17-09-2014, 10:17 PM
I could probably source a chunk of tassie blackwood for the sound board.... Be a heck of a lot better sounding than ply :))
No problems machining it down to the correct thickness either.. I have the toys..errr...tools to do that :)

ihasmario
17-09-2014, 10:28 PM
I'll email you the details of the soundboard as it looks at the moment some time on the weekend, and revise my size (or wood choice) depending on cost - and the maths of it since the tension on the soundboard is going to be somewhere in the region of 400+kg.

The soundboard blank, if it was Birch would be in American - 1/8", 15-3/4", 49-3/8". So it could end up being too $$y for me. If blackwood is expensive, I'll definitely give it a go on the miniature one I'll make first.

I've got a feeling that depending on the direction of the grain, the blackwood would need to be thicker though. But I need to research that a bit more. :)

maxaxe
18-09-2014, 01:13 AM
"To boldly go where . . . . . "

Sounds scary to me, but at the same time fascinating.

lawry
18-09-2014, 06:58 AM
Damn. That's one serious project you've set yourself mate. Really looking forward to the diary on this cos I have no idea how to put one of these together!

stan
18-09-2014, 11:57 AM
wow, what a project. Good luck, sounds very interesting

ihasmario
06-10-2014, 07:49 AM
Some slight changes, rather than designing the harp, I'll be using an existing blueprint and modifying it slightly (think blank headstocks from PBG). While I would have really liked to do a true scratch design, I simply don't have the time to bend my head around all of the physics required to get something that sounds right and won't fall apart. :)

Here's the three (four if you include the two sides) major structural pieces laid out. The smaller bits will come later. In the center is all the harp related hardware - 34 strings, 34 bridge pins, 34 tuning pegs. No sharping levers, which alone would double the cost of the harp materials of the harp for a fully chromatic instrument. I will probably add some later but I want to make sure the harp ends up working before I shell out the cash for it.

The gap is for a part I haven't cut out yet. Still got lots of reading to do so I know what the types of cut the blueprints refer to so I can tell DB what I need when I inevitably step into the man-cave.

:) Bit busy at the moment (recording a lot of music), so progress will be even slower than I expected

Cheers.
http://www.pitbullguitars.com/wp-content/uploads/2014/10/n0061-harpprogress.jpg