Dovetail neck joint

[sprucetop1]

I've completed one steel string guitar using the StewMac machined and dovetailed neck and neck block (the rest was home built), and I'm an a second guitar and an F model mandolin. This time I'm trying to do everything myself, but am having great difficulty with hand cutting the neck dovetail on both. Have tried several dry runs in scrap wood for both the mandolin and guitar neck joints, but seem to be a long way from successfully achieving a good fit plus all the correct angles. Any advice to assist my struggles would be very gratefully received. I want to avoid the machine routing method if I can due to cost.
thanks...John

[sunburst]

In the words of Jim Hilburn: "centerline, centerline, centerline".

Go slowly and think about each cut and what affect it will have...try to predict.
Go ahead and finish fitting your practice joints with shims if you cut away too much and learn from the process.
Look at good dovetail joints when you have the opprtunity. Try to make yours look similar.

Just keep at it. It takes a while to learn.

[Chris Baird]

http://www.thefishnet.com/makemandolin/newmake.htm

[sprucetop1]

Thanks a million guys for the posts. Those images are extremely useful. It's back to the bench for more practice on scrap........
John

[bt345]

Also search "Dovetail re-visited" on this website; an excellent, simple idea with photos by Jim Hilburn, again.

Good luck...

[sprucetop1]

Bill: thanks v. much for the reference to "Dovetail revisited".....I missed this post on my 1st search thro' this site, and thanks Jim for the photos and your bandsaw method. This looks like a great way to go, and should be feasible for guitar neck blocks and necks as well. This is just what I need......thanks again

John

[Jim Hilburn]

John, I also posted how I do the layout in another dovetail thread, and that wasn't all that long ago in case you want to go on another search.

[ShaneJ]

Jim, I looked for the layout thread, but I couldn't find it. Do you happen to remember the title of the thread? Was it in the Builder section?

Thanks for all your helpful posts! I know a lot of us really appreciate it.

Shane

[Jim Hilburn]

It's in a thread called "upper cap on neckblock".

[douglas2cats]

You mentioned you're using handtools. Don't know if you're already trying this, but one thing that can't hurt is to clamp a thick scrap block onto your pc and use it as a fence to register your tool against as you cut/chisel down into the wood. This can help reduce drifting off from the cut you intended. Just make sure the guide block is perfectly square (or perfectly angled if you're after a taper) and keep your tool flat against it as you go. This won't help much with the curved cuts, but could help make the straight stuff more precise. Note - this will work for sawing but works better with a completely flat saw. A stiffening bead along the top of the blade means your guide block needs to be low enough to clear the stiffener and then you dont end up getting as much guiding support out of it.

[Chris Baird]

A cool tip for guide blocks it to inlay a big ol' magnet in the side of if such that it sits just inside the wood. It draws the saw blade into the guide but doesn't touch it. I've been experimenting and I can get some straighter cleaner cuts than with my bandsaw.

[amowry]

I saw that tip in Fine Woodworking recently and I'm planning on upgrading my fret-slotting miter box with magnets to remove play. It's a great idea.

[wtaylor]

You mentioned you're using handtools. Don't know if you're already trying this, but one thing that can't hurt is to clamp a thick scrap block onto your pc and use it as a fence...

Will this work with a Mac as well? http://www.mandolincafe.net/iB_html/non-cgi/emoticons/rock.gif

[amowry]

I would highly recommend the slightly compound dovetail that Jim describes, rather than the perfectly straight one that Lynn Dudenbostel seems to use (is this correct Lynn?). #I've been experimenting a lot, and the slight taper seems to really help get the joint tight near the heel, where a tight fit is most critical. #With completely straight sides, there's no room for error, and everything has to be right the first time. #Anyone else care to weigh in on doevetail styles? #I apologize if this has all been discussed here already.

Edit: Maybe this came off a bit strong, I didn't mean to suggest that Lynn doesn't do it right, just what seems to work well for me. :)

[Chris Baird]

I'll second the slight compound angle. I cut the female part with a router such that the bottom is about .020" smaller. That way I can cut a straight male part and just do a little hand work to get it down all the way with a tight fit on the bottom.

[sunburst]

I cut my dovetails with hand tools. I too prefer a tapered dovetail for the "locking" characteristic.

[Ward Elliott]

Same for me. For a long time I fit my necks after both the top and back were glued, but recently found out how much easier it is to do before the back is glued on.

[sunburst]

Ward,
If you haven't found out yet, be mindful that you have to control the neck angle as you glue the back on and not let it change in the process.
I found out the hard way so I thought I'd pass it along on the off chance you didn't know.

[peter.coombe]

Yes I use a slightly compound dovetail as well. I used to do a straight dovetail as Lynn does, but changed when I discovered a slight compound seemed to give me a tighter fit, particulalrly in the heel region. I cut it straight in the bandsaw and cut and fit the compound by hand. I also fit and glue the dovetail before the back is glued on, much easier this way.

[ShaneJ]

sunburst, I'm a rookie. What should I watch out for in gluing the back on after the neck exactly? If the dovetail joint was fitted and neck glued properly (and cured), how could I mess it up while gluing on the back?

I'm not doubting you a bit, just trying to learn something. http://www.mandolincafe.net/iB_html/non-cgi/emoticons/smile.gif

Thanks!

[sunburst]

SJennings, with the dovetail well fit and the neck angle correct with the back still off of the mandolin, you'll find that the rim can flex right much. You can hold the rim and push on the neck so that the projected bridge height would be higher or lower depending on which position it was in when the back was glued on.
All you have to do is make sure it doesn't flex from clamp presure and end up with the wrong bridge height.

[ShaneJ]

Ah...that makes sense. Thank you!

[Stanley Cox]

SJennings,
I am greener than green,newer than a newbie,but
I got the McRostie video. (No financial interest.) He covers
neck setting simular to what Sunburst said.How high is the pile of shavings and saw dust? My kit is coming along slowly.
Stanley http://www.mandolincafe.net/iB_html/non-cgi/emoticons/coffee.gif

[ShaneJ]

Stanley- I finished making jigs and patterns yesterday. I hope to actually get started on the good stuff this weekend.

[GaryM]

bump http://www.mandolincafe.net/iB_html/non-cgi/emoticons/coffee.gif