i'm a newbie and i need some advice on cupped Mahogany

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aisuru

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evening everyone, looks like a nice place, hope i can get some helpful answers around here.

some background first of all: i'm not a professional joiner by a long shot. i could have been, though, and i'm still angry at the careers advisers who told me, when i was leaving school, that there were few jobs for joiners going. i found out two years later than the construction industry was crying out for apprentice joiners, and so now i work in an office - won't name my employer, as it may turn you all against me. anyroad (sorry, i tend to go off on tangents quite a lot) i'm a bit of a newbie, having done no real woodwork since i left school about six years ago - and even then, i'd hardly call that 'real' woodwork. regardless, i'm building a guitar the now, with my bandmate Captain Circle-jack (a fearless and mighty pirate).

he decided he wanted a new guitar, and it had to be 'glam' and unique. however, he didn't want to pay through the nose for a professional luthier, so we hatched a plan involving eBay, a load of hardwood and some power tools.

we ordered a load of Brazilian Mahogany over the internet - 3M long, 295mm across, 50mm thick. i cut a bit off the end, and that's what we're using to make the body of the guitar at the moment. it's nearing completion, no real problems (apart from our incompetence, but that'll just add 'mojo' to the finished guitar!) but the plan for the rest of the wood is to cut it into strips and make 3-4 more body blanks out of it, either for more guitars in the future, or for eBaying to recoup some costs. problem with the rest of the wood is it's slightly cupped.

i don't think it was always that way, i don't remember it being too bad when i took delivery, i think it's a more recent development while sitting in the garage.

aaaanyroad, what would be the best way to straighten it out? i've got a cheap power planer, but no access to a thicknesser right now - or for the foreseeable future, since i'm a bit skint. the plan was to cut the board into sections of certain width and glue them together to make broader blanks, but should i try and get them all flush before glueing, or glue them together then plane the blank flat? and what would be the best way to go about this?

cheers in advance and apologies for writing War & Peace as my first post :?
 
Hi aisuru and welcome.

How cupped is your timber, a picture would help. if it's not to bad you may be able to rip into lengths plane and glue together, is your garage very damp?

Dom
 
I would tackle this by ripping the boards in half and then jointing them with the planer and re-glueing them back together. If you don't have access to a jointer/planer I would use a router and a straight edge to plane the edge square and then re-glue them. Also alternate the boards by turning one witht he growth rings up and the next down this should help stabilise them a little. My ha' penneth, maybe someone else can suggest something better? :wink:
 
Hi aisuru

Welcome to the forum

I don't know the answer to your question but...

Your forum name is very interesting....in Japanese;

Ai = love
Suru = do (to do)

The combination of Ai & Suru means "To love"

Is that what you meant in your forum name? :)

niki
 
thanks for the welcome everyone, and for the quick response!

i'll try and get a photo of the timber tomorrow. i don't think it's too bad, but it's not quite perfect. i've got a planer and a router - both cheap ones, but they work.


Niki":1rjlmavh said:
The combination of Ai & Suru means "To love"

Is that what you meant in your forum name? :)
aye, kind of :lol: i picked it at random from a Japanese phrasebook a few years back, used it ever since all over the place.
 
hello, aisuru.

Any board 12" wide 295mm in my opinion is going to cup. (I've got some boards over 24" wide and they must be 50 years old, and they are cupped. Too heavy to take down from my storeage spot at the moment and if I rebuild them they will still be too heavy :roll: )
So I think you will have to follow advice above, perhaps rip it to 8 pieces and reglue alternatively.

By the waqy I studied your username, I tried reading it backwards but no luck that way.
 
i think that may be the best option. either that or just make another four narrow guitar bodies! :lol:

as promised though, here's a pic of the timber:

DSCN3819.jpg


i measured the gap in the middle, and it's aprox 2mm.
 
If you rip that board at angles instead 0f 90% you could finish up with quarter sawn boards. You will lose a bit though.
 
eh... could you explain what you mean by that a wee bit please? i don't have a tight grasp on all the jargon quite yet :?
 
aisuru":3qftog5h said:
eh... could you explain what you mean by that a wee bit please? i don't have a tight grasp on all the jargon quite yet :?

have a look at this thread. Click the link below.

http://www.woodworkforums.ubeaut.com.au ... hp?t=54294

Quarter sawn timber is reckoned to be more stable, your boarde cups on the grain lines, QS has very short distance grain rings.
 
That's not serious cupping, if it has now stopped I would face plane it first, it only looks like a couple of millimeters then using that face as a guide against your fence plane one edge square to it.
Next plane the other face a couple of mill. and see how it looks, should you need to take more of, alternate the faces to keep tension equal.

Dom
 
I think the saw cuts are obscuring the grain , that to me looks like through and through or plain sawn . To get good quater sawn you would lose alot of timber in thickness and width . Then again i just but it in so don't really get involved in this bit :oops:
 
No fair Jon.

Forum rule 93, clause 57 sub-section C.

No member shall be discriminated against whether by race, colour,creed or nature of employment.

:)

Dom
 
DomValente":1zthv4mx said:
No member shall be discriminated against whether by race, colour,creed or nature of employment.
phew, saved my skin that one! :eek:


anyroad, i think i get the idea about the quarter sawing. problem is, that'd take an age with the tools at my disposal right now - the quickest being a Bosch powersaw, which will still take an age and isn't really designed for precision cuts like that. i think i might be able to get a loan of a tablesaw though, i'm sure i'll know someone who's got one lying around.

cheers for the replies everyone!
 

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