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Hi

I recently purchased the Jon Simpson neck jig, I ran a trail yesterday and trashed my template (but that is another story)

I did finally cut a dovetail tenon, the length (not the depth) of the dovetail is about 95mm - my Martin OM plans have a depth at the neck of about 85mm - obviously the tenon is too tall for the body of the guitar. I am thinking I have to make a new template with a shorter tenon, has any of you who are using the jig experienced this ?

John

The templates are fixed, I think I will have to remodel the jig to make the profile adjustable. This means I will need to make new templates which defeats the objective of buying this jig in the first place. I think I need something like this

viewtopic.php?f=10101&t=27922

Thanks

John

Hi John,
Shouldn't be too hard to drill a couple more sets of mounting holes in the top of the jig so that your templates become more adjustable. It looks like there'd be room to do that and it would be less work than making another template.

Cal

_________________
Remember, there are no stupid questions, only stupid answers!

Agreed, but I trashed the template on my fist trial - I should have paid more attention to what I was doing - so I need to make a new template anyway. I will also make the top table a little bigger so my router has more room. I may even consider buying the stew mac templates and remodeling the jig to make them fit.

Have you talked to Jon Simpson???

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Dave
Milton, ON

Yes I did, but I don't think he fully understood my question - there was confusion between depth and length - so I thought I would post it on the forum to see if anyone else has come across my issue.

I am also considering packing the neck blank which also has the effect of shortening the dovetail, I am not sure if thsi will have an effect on the angle setting feature.

Maybe I should post some pics and start a new thread.

Regards

John

Hey John, I just got my simpson jig this week and see the problem you're talking about. I sent an email to Jon asking about making the router template adjustable as some of my builds are only 3" deep at the neck. He suggested using a spacer under the neck to shorten the tenon, with a spline on each side to engage the jig and the trussrod slot. Apparently the jig is set up to give proper tenon depth for dread depth guitars, so some adjustment is needed. Shouldn't affect the angle.

Joe

I received my Simpson jig a month or so ago. It works perfectly as advertised. It really takes a nerve wracking job and makes it easy and accurate. I also picked up his brace radiusing jig it too works as advertised and is more accurate than trying to radius on a radius plate. I've also used the jig that clamps the brace into a forced bend and then run across a joiner or an abrasive planer. While the latter works well it's a pain to set up.

I'm glad I read this post because I will be cutting a mortice and tendon on a Ditson grand concert shortly and had not anticipated this problem. I'm sure I would have spotted the problem when I went to do the job. On the Ditson plans I've looked at the body depth varies from plan to plan but all require a shorter tendon. I guess I'll have to shim out the neck to shorten the tendon. Shouldn't take but a few minutes to build the spacer. It sure beats the old way of cutting the tendon on the table saw.

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"Try to be the person your dog thinks you are."

http://sites.google.com/site/bertsguitarshop/

I was beginning to think it was only me - let me know how you get on and I will let you know when I have made my modifications and run some tests. I made my own radius jig a few weeks ago, I can't remember where I got the details from. I didn't know about Jon's radius jig - I'll post a picture of mine later today.

Regards

John

This is the brace jig I made 15 & 28 degrees - seems to do the job OK, is this the same as your brace Jig ?

You jig is similar to my old jig where you force a bend in the brace and then level and when it springs back you have your arc. Nothing wrong with that design I've used it for years.

The Simpson brace jig requires a flush cut bearing bit that follows a pattern. It can be used with a table mounted router using a pattern bit with the bearing under the cutting surface. I have an over-arm router so I use a flush cut bit with the cutter above the bearing. His pattern board has two faces one with a 15 foot and the other with a 25 foot radius. He can make the pattern what ever radius you want. *

*I hope I'm not talking out of class. My apologies Jon if that last sentence isn't true.

_________________
"Try to be the person your dog thinks you are."

http://sites.google.com/site/bertsguitarshop/

Hi Bert

I would be interested in seeing that, I started out trying to make braces on my router table but it just tore them to pieces.

John

If I understand you correctly it should be an easy task to adapt it to an adjustable StewMac template. Just drill 4 hole and use knockdown furniture or pan head bolts. You can either drill through the top plate and use wingnuts on the underside or see if the ply will hold a thread or use brass inserts. I'd probably also scribe a centerline on the template and maybe another at a 90 for the top of the neck, might make setup a bit faster. Here's a picture of the SM template over the top and you can see there's plenty of clear space for the bolts to go. That's a future adjustment I'll be making to mine even though I haven't the need for it now. You could also cut the template down to the same size of the table and put side rails on it to keep the template square but I think the scribe line would eliminate the need for that.
And then if you don't want it to be adjustable and have a set length in mind you can just set the template and clamp it in place and then drill some new dowel pin hole and set it with pins like the original.
You will also have to slot the template for the bar too.

But it would be a lot cheaper to make your own template and shorten the length.
http://www.stewmac.com/shop/Tools/Speci ... lates.html

John,

I first draw a pencil line using the pattern and cut to the line with my bandsaw first. So all I'm doing is clean-up with the jig. I suppose I could just use a sanding drum with a follower on the drill press and accomplish the same thing.

Bert

_________________
"Try to be the person your dog thinks you are."

http://sites.google.com/site/bertsguitarshop/

Yep I have already come to the conclusion that the templates need to be movable to facilitate different lengths of tenon, in my case they are both too long. Making the templates and getting them accurate is not an easy process and it is time consuming. I already re made the one I trashed to the original dimensions which in hindsight was unnecessary although it did provide me with some practice.

John

You might be better off to just go with a mortice and tennon and forget about the dovetail in more ways then one.
It shouldn't be that hard to make the template. You can trace the mortice template to copy and match the dovetail shape an adjust the length to what you need. Use a scroll saw to ruff cut the template out and finish up with a file or whatever. Or use a router Inlay Kit to make your own.
http://www.woodcraft.com/Catalog/Produc ... 4d343cf390

Hi Chris

Yes a straightforward tenon is the easiest option and it will probably the way I will go for teh majority of builds I intend to make. However it very rewarding and provides a great deal of satsicfaction in cretating a good fitting dovetail joint. I'll not give up on it completely.

John