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Forum topic by AGolden posted 06-12-2020 09:44 PM 494 views 0 times favorited 7 replies Add to Favorites Watch
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AGolden

54 posts in 137 days


06-12-2020 09:44 PM

Hello all,

I am building an Irish harp and need some help with the joinery. There are really only three joints to cut in the whole thing.

the mortise and tenon between the pillar and the soundbox,

the mortise and tenon between the “neck” and “pillar”,

and the dado joint between the neck and soundbox.

I can get all three of the joints to seat individually but if i try to put the whole thing together they never quite get there. with the dado at the top of the soundbox being the worst as it rotates out of position.

My question is this: I know i have to adjust the joints to make them all fit together but I am not sure exactly how to approach it and in what order. I don’t want to run around to each joint making changes and end up with sloppy joints all around. my current plan was to deepen the dado at the top of the soundbox and put it at an angle to match the rotation of the neck and go from there. let me know if you have any tips on getting tricky joints like this to come together when they all have to essentially fit together simultaneously. Thank you!


7 replies so far

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SMP

2248 posts in 708 days


#1 posted 06-12-2020 09:52 PM

Its things like this I really like drawboring. Its a way to pull those joints together and hold them tight, even if they have to be a little “loose”. And especially when clamping would be awkward. Chris Schwarz wrote a great article on it that helped me.
https://www.popularwoodworking.com/techniques/drawboring-resurrected/

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AGolden

54 posts in 137 days


#2 posted 06-16-2020 02:01 AM



Its things like this I really like drawboring. Its a way to pull those joints together and hold them tight, even if they have to be a little “loose”. And especially when clamping would be awkward. Chris Schwarz wrote a great article on it that helped me.
https://www.popularwoodworking.com/techniques/drawboring-resurrected/

- SMP

I may try this in the future and do it intentionally. it may not work in this situation as a fix. I have been able to get it a little tighter but man it feels more like a carving project than a joinery project, there has got to be a better way than this.

View bandit571's profile

bandit571

26126 posts in 3486 days


#3 posted 06-16-2020 02:54 AM

Maybe the part that is a single curve…needs to be a wee bit longer? THEN, you can trim it down until the fit is perfect….

-- A Planer? I'M the planer, this is what I use

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AGolden

54 posts in 137 days


#4 posted 06-16-2020 04:56 PM



Maybe the part that is a single curve…needs to be a wee bit longer? THEN, you can trim it down until the fit is perfect….

- bandit571


View Axis39's profile

Axis39

261 posts in 400 days


#5 posted 06-16-2020 09:10 PM

I think the neck and pillar should be fit together, first. Then, they, as a unit, should slip down into the mortices on the soundbox.

The reason I say this is that the two joints between the sound box and the upper pieces look like vertically fit joints. You would want the tenons on the two upper pieces parallel, and ‘plumb’... and the mortise/dado would also be plumb.

Right? Or, am I not getting something.

-- John F. SoCal transplant, chewer uppper of good wood

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AGolden

54 posts in 137 days


#6 posted 07-14-2020 09:19 PM

Update,

all done, some tactical shimming of the shoulders eventually got it to a place where i wanted it to be. If you look at the neck the joint between the neck and pillar did get some “draw bore” effect because three of the tapered tuning pins go right through the tenon. I also ended up making the neck to soundbox dado a little deeper

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23tony

40 posts in 972 days


#7 posted 07-15-2020 04:43 PM

Looking good! How does it play?

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