dovetails and tenons with CNC?

[al ladd]

I'm early in the process of building a larger version on the JDS multirouter, a xyz joinery machine that works with a horizontal router, and can be used with a template follower to cut tenons and traditional dovetails. I use a similar, lightweight version, the Matchmaker, (from Woodworkers Supply) for lots of joinery and hardware mortising for my jewelry box making business, but want a longer x axis, and something stouter that will be less sensitive to operator pressure on the template following stylus, especially on dovetails. Now I realize I'm being somewhat of a luddite in not making this machine a CNC machine, but it's already a big project, and I know nothing about CNC. Also, the joints I cut typically take only 15-45 seconds to cut with a manual template follower machine, like I'm looking to build, so the time savings aren't immediately obvious to me -although making good templates is laborious. I also don't see CNC machines using a horizontal router, so one would either have to come up with methods for clamping pieces vertically perpendicular to the table, or design a machine unlike the great mass of existing CNC routers. (I guess I"m looking to build something like http://www.gold-state.com/New_Machines/Maxym/maxym.html ) Am I being ridiculous in not tackling this as a CNC machine? The xy table I"m using, bought used off eb*y, was obviously CNC controlled in its earlier life, and built with THK rails and bearings. I guess I"m also wondering why the sort of thing I"m looking to build (in a CNC version) isn't widely commercially available, or are there machines that allow for both regular and horizontal router mounting? Thanks for advice on this!

[Rob Wright]

I read a post last year on the rec.woodworking site about a man who built a cnc to cut M&T, three types of dovetails and two types of box joints.

He had written his own interface for it as well and was selling them.

Google " Morris Dovey Desoto Solar" the 5th result is his home page - send him an email and see if he is still making them.

It's worth a try -

[Dennis Ford]

I have cut dovetails on my home made CNC router. It works fine but is NOT faster than your template based system. You could build your unit with CNC and possibly gain a lot of versatility, I doubt you would gain speed without spending a lot of money.
;)

[Matt Zettl]

I have a ShopBot CNC router as well as a Matchmaker. Although I have not attempted dovetails on the CNC, I have cut a lot of mortises with it. It is much faster than the Matchmaker, once one has learned how to the lay them out and toolpath them with CAD/CAM software.

Cutting tenons is more of a challenge. Although I have cut them on the CNC with the workpiece in the horizontal position, the piece has to be flipped over to cut both cheeks of the tenon. This requires very accurate registration of the piece once it is flipped. A better technique is to build a fixture off of the end of the work surface to hold the piece vertically. This would allow the cutting of multiple tenons with the workpieces held vertically. I plan on adding this to my CNC setup, as it would also be faster, as well as more accurate, than the Matchmaker.

Finally, I have to say there is a rather steep learning curve with a CNC machine. If you already have experience with CAD software, then you will have a good head start. You have to be willing to put in a lot of time learning the software and the machine in order to use it efficiently and effectively.

Hope all this rambling helped.

-Matt

[Ian Strouse]

Hermance has a line of Dovetailing machines that range from basic manual machines to highly automatic CNC machines.

Thanks,
Ian