1Q22 challenge - DartmoorHedgehog's solid-body mandolin

DartmoorHedgehog

OK, I'm up for this "build a thing" challenge - I need something to take my mind off other shit at the moment.

I've got a piece of maple left over from making an electric violin some time ago, about the right size for another similarly-sized instrument.  So the plan was to build a solid-bodied mandolin.  I got as far as making a pickup using the parts of a dead dano-style lipstick I had (https://www.thefretboard.co.uk/discussion/200740/ if you're interested) but then the project has stalled a bit.  So I intend to get my arse in gear and build the rest.

(Hopefully it's within the challenge scope... not really "guitar-related" as such, but a fretted stringed instrument with similar construction.  If it's not, feel free to kick me out of the challenge, but I'll post the build updates anyway - it's not as if I'm likely to win anyway )

downbytheriver

Perfectly within the scope - I look forward to seeing it! 

DartmoorHedgehog

Cool - hopefully I'll have something to post soon.

paulnb57

Excellent!

DartmoorHedgehog

OK, made a bit of progress on this today.  It's going to be a neck-though construction (mainly because I don't trust myself to make a decent neck joint with the tools/skill I've got).  The neck will be made out of the piece of maple I had left over from the violin, and the wings, top and back will be whatever I can find.  I'll probably hollow the middle out and put f-holes in the top - not sure yet whether to try to carve a domed top or just leave it flat... see how ambitious I'm feeling when I get to that stage!

I've blown up some mandolin plans to full size to give me a guide for neck angle etc.  So far I've marked up the neck on my piece of maple and made all the straight cuts - some with a little table saw and some with hand saw (I'm quite envious of anyone who has a band saw).  Next will be the cut underneath the neck, which I'll have to do with a fret saw.

I haven't decided yet whether to make the body f-style mando shaped or go with a sort of DC LP Junior shape.  At the moment I'm leaning towards the LP shape, both for simplicity and looks.

Not very interesting yet, but here are a few pictures of where I'm at:
(Pictures seem to be weirdly rotated for some reason... they're the right way up on Flickr )

paulnb57

Wow! Enviable skills!

DartmoorHedgehog

Little bit more on this today.  Epic cut along the back of the neck with a fretsaw - pretty slow going in 2" thick maple!  And I think the body shape is going to be a single horn like on a F-type mando, but without the scroll, so sort of somewhere between my two original ideas.  I've bought a piece of grenadilla for the fretboard, which should be here in a few days.  I need to buy a tailpiece and some tuners, but I think I'll make the bridge and nut from scratch.
Not quite sure what wood to use for the top and back yet... I've got some beech logs that are destined to be firewood but the bigger ones are about the right size for a mando body.  I'm tempted to cut a slice of one of those and see if I can dry it out in the oven - no idea how possible that is or whether it's a silly idea (when wood is "kiln dried" is it pretty much just cooked in an oven?) so need to do some more research. It doesn't need to be structural because of the solid through-neck and wings.  Am I mad or is it worth a try?

Here's how my rough cut neck looks now, and my sketch of the body shape.

DartmoorHedgehog

Weather's not been on my side this week, but I've managed to make a bit of progress. 

The piece of grenadilla for the fretboard arrived, and I've cut that roughly to shape - still needs the fancy bit at the end cutting, then thinning down a fair bit (it's 9mm thick at the moment) before I mark and cut the fret slots.  I've got some brass-coloured (not sure if it's actually brass) fret wire left over from replacing a couple of frets on an old banjolin, so I'll probably use that rather than buying something else - it's probably softer than normal silver-coloured frets but I don't play mando that much so I reckon it'll last fine (the frets on the old banjolin are not bad after 100 years).



I've also cut some slices of the beech logs with the hope I may be able to use them for making the top and back.  If I can successfully dry them out enough without them cracking or warping too badly then I won't need to buy any more wood.  Bit of a gamble though trying to speed up the drying process... @roland suggested on another thread that I may get away with microwaving small pieces, and apparently beech is quite forgiving split-wise, so I may have a chance - nothing to lose if it fails. Some quite interesting spalting on some of the bits as well.  We'll see what happens...  might all end up as firewood (which is what it was intended for anyway). Wish me luck

TTony

DartmoorHedgehog said:

. Wish me luck

Good luck!

paulnb57

Good luck!

Andyjr1515

I like this very much...

...oh, and good luck 

DartmoorHedgehog

Thanks folks. I know it's a bit of a long shot trying to dry this wood quickly but I've got nothing to lose except a bit of time. It'll be an interesting experiment even if it fails, and if it does work I'll have some cool very local wood (it fell on my fence). Plan B will be to buy some wood, but that's boring (and expensive)

DartmoorHedgehog

Well, today I finished off cutting the curvy end of the fretboard - next thing to do with that will be to thin it down a bit before cutting the fret slots, but that will have to wait for a dry day so I can do it outside (I'm going to have to take three or so mm off with a sander, so lots of mess...)


In the meantime I thought I'd try drying some of the beech.  It's too big to fit in my microwave, so thought I'd see what would happen in the normal oven.  Two slices in on a low oven until they stopped steaming (bit more than two hours) and they stayed amazingly flat and uncracked.  So I did another two pieces the same way.  I'll leave them standing in the house for a couple of weeks until I get round to needing them, but they feel very dry to me so I reckon there's a good chance of being able to use them.  I'll probably cut the end off one of them in a week or so and see how dry it feels when filed and sanded - if it's not properly dry I can cook it a bit more, but I think it may well work after all, which will be cool.

DartmoorHedgehog

Fretboard is coming along nicely.

My thicknesser is two strips of 4mm steel, an angle grinder and a scraper - worked fine.


Fret slots cut with little jig and junior hacksaw. The two 3mm drill bits are being a depth gauge.


Dots inlaid and frets pressed in.


Fret ends need snipping off and filing, then back to the neck and body. I've got the machine heads now so can plan the shape of the headstock. Also bought a tailpiece, but I plan to make the bridge and nut from scratch (probably with some of the offcuts of maple).

paulnb57

Excellent progress

Roland

I’m glad the beech hasn’t cracked.

DartmoorHedgehog

Roland said:

I’m glad the beech hasn’t cracked.

It seems to have survived the cooking pretty well.  Very slightly warped but it wasn't completely flat anyway so was going to need serious sanding (I just cut slices freehand with a chainsaw).  It's been inside since I baked it so I'll have a go at filing a bit of it soon and see how it feels - I'm quite optimistic it'll be good enough for this though where the main strength is in the maple spine and whatever I use for the wings and the beech bits will be pretty much cosmetic. We'll see...

Roland

If you’ve got a router you could make a router sledge, and flatten it with that.

davros

Not seen thicknessing with an angle grinder before!!! You're a braver man than me!

DartmoorHedgehog

@Roland no router I'm afraid. My tool kit is much more mechanic than luthier, or even woodworker for that matter. I do have a plane, saws, big rasp, scrapers and a little table saw, but some improvisation still has to come into play.

@davros thanks... It worked pretty well, angle grinder to get rid of the bulk of it then scraper to make sure it was flat and down to the thickness of the steel strips. I did try a more subtle approach with a sanding block but grenadilla is so hard it was going to take days. 

DartmoorHedgehog

Nice dry weekend here for a change, so I've managed to get some more of the messy parts of this done.  I've made the rough headstock shape and drilled the holes for the tuners.    Basic body shape is made with hole for control cavity (and some probably pointless "weight relief" holes), and a long hole for the pickup wire.


Fret ends are trimmed (but not filed yet - I find that easier to do when it's stuck to the neck). And I've made a support piece for the end of the fretboard.


So now it's starting to look a bit like a mandolin.


I've planed down some of the beech so it's fairly flat and will be able to be clamped onto the top and back of the body. Not perfect but there's enough flex in the wood that the clamp pulls it down, so hopefully it'll be good enough once the glue dries.  Next jobs are some more neck shaping and sticking the beech on...