Best way to cut a 60" mortise?

[dennis thompson]

I am building a patio serving cart for my outdoor grilling.
I need to make a 1/4 inch wide by 1/2 inch deep mortise along center of the side of a 3/4 in thick board which is 60 inches long.
The mortise will run the whole 60 inches to accept about 26 tenoned boards
What do you suggest as the best way to cut the mortise?
Thanks
Dennis

[Doug Shepard]

I'd use a router with edge guide and do 3-4 passes to get to full depth.

[Doug Shepard]

Oops - I missed,
The mortise will run the whole 60 inches ..
Thought this was a stopped mortise. Dado blade would be my new choice.

[David Tiell]

Agree with Doug on the dado blade.

[Russ Sears]

How wide is the 60" long board?

[dennis thompson]

The 60" board is 2 1/4 inches wide

[Tim Marks]

Seems like a job for the router table. I have done this in 48" of hard maple without much trouble with just a stright bit. An Up-Cut Spiral Bit would work better, since you wont have to stop ever 6" or so to clear the chips out of the groove.

Or you could use a rabbet bit, which would also keep the groove clear. But it would require more work with a chisel to dress up the end where you stopped cutting.

Why are you cutting all the way down instead of just a separate slot for each mortise? You would be better off asking how you will cut a rabbet in the board instead of a mortise.

[Peter Quinn]

I have cut very long 1/2" deep mortises for splines with a 1/4" slot cutter and router...simple, accurate and puts much less stress on the shaft than any other setup. I'd use the router freehand (use test pieces to set the mortise location).

TS with dado or two passes with a rip blade would be my second option.

I would only resort to router table with straight cutter if I had nothing else, as any deflection will easily distort the mortise. Also it will take multiple passes, more chances to mess it up. If you use the router table/straight cutter very good hold downs/feather boards/ infeed/outfeed support will be essential over 60".

[James Hart]

This thread has me wondering; at what point does a mortise technically become a groove or a stop groove? I'm thinking the difference is really semantic, but I'm curious if there is a defined difference between the two.
I'm thinking it's a mortise when the mating piece is either cut to an integral tenon or to accept a loose tenon. Or maybe when the joint is used to connect parts of a frame as opposed to sides of a case.

[Peter Quinn]

A mortise has sides to accept and support the tennon shoulder...mortise and tennon are a pair like love birds! Mortises rarely exceed 4" in width as they are made to strengthen what would otherwise be a butt joint, with two pieces of wood set perpendicular moving in different directions.

You are making a dado and using its slot like a mortise, but it is not in fact a mortise as I know it.

[dennis thompson]

I guess I'll have to call it a dado since I cut it this afternoon with my dado blade & it worked very well.
Thanks for all the advice
Dennis

[Rod Sheridan]

I guess I'll have to call it a dado since I cut it this afternoon with my dado blade & it worked very well.
Thanks for all the advice
Dennis

In my opinion, it's neither.

Since it runs with the grain, it's a groove.

I'd cut it with a slotting cutter in the shaper, or a rip blade in the tablesaw since it's easy to flip the piece to center the groove.

However, the important thing is that you accomplished the cut in a manner that suited your tools and needs.

Regards, Rod.