Cutting M and T joint on my 12 string - for Showtell

[kiwigeo]

Some time ago Kim (Showtell) PM'd me on another forum with a request for details on how I do my M and T neck joints using the Woolson jig. Over a series of posts Ill try and capture the procedure. Im due back at work next week so I may not get everything done before then.

Criticism as well as praise most welcome.

The first lot of pics shows the body of the guitar set up in the jig I use for cutting the body mortise. The jig is the end product of consulting numerous texts and journal articles on the subject. Before jigging up the body I make sure the front of the body where the heel will be in contact with same is perfectly flat. if its not flat then youre wasting your time. The cutter in the router is a Stewmac dovetail cutter. The templates in the jig are also from Stewmac.

[gratay]

Martin , this would be very helpful as this is the next step I need to research in my build and was wondering how you all do it..
I will be watching and looking forward to this thread unfolding.
thanks for your effort in advance.

[kiwigeo]

No worries Grant. As posted I may not get the whole job done before heading off to the North West Shelf on Wednesday. Should get the mortise routed tomorrow and might get the tenon roughed out before I go.

Note that the jig Im doing the mortise with is not the Woolson jig. I used to use the Woolson jig for both the mortise and tenon but have found it quicker using the seperate jig.

Cheers Martin

[kiwigeo]

Okay I got the mortise cut this morning. went okay apart from a slight boo boo half way through when router depth stop slipped. The router is trend T5....like anything out of Pommy land it has a terrible whine so ear muffs and safety glasses are a must.

The mortise depth I aim for is 20mm and for the tenon its about 17mm, ie a 3mm gap between the back of the tenon and the bottom of the mortise.
Pic 1: hogging out with a straight cutter..think it was an 8mm double fluter.

Pic 2: Cutting with the dovetail cutter. Router depth stop slipped halfway through this operation leaving depth of mortise a bit larger in one spot. Not fatal but I should have checked the depth stop..the things can work lose during a cutting session.

Pic 3: Checking height of the mortise withy the caliper. I want about 75mm at the back of the mortise to match the height at widest part of the tenon.

Pic 4: The finished cut. You can see where I cut a bit deeper than I wanted to when the depth stop slipped on the router.

Pic 5: and from the top. A bit of chip out on the top but fretboard will hide same.

[kiwigeo]

Tuesday and I managed to cut the neck tenon and get it half fitted. Photos were taken of the process but Ive run out of time and posting of same will have to wait a few weeks until I get back from work.

Cheers Martin

[Kim]

Thanks Martin,

Have a good stint mate and don't go getting too carried away with the pallet wood. looking forward to your next installment upon your return.

cheers

Kim

[matthew]

How would this have been done before routers?

[Kim Strode]

Hi Martin,

Thanks for your efforts so far.

Thanks, Kim Strode