so I have a cabinet to build with a dish display rack which requires routing 14 identical mortises in alder veneered mdf. a few months ago I upgraded my drill press to a mill-drill for just this sort of thing. a router template made with machine tools....
first I ran the "tennon" stock through the performax. there are no shoulders- the ends of the sticks set directly into the mortises- so the fit is critical. gang the parts and run them in batches for consistency. got them to a decent dimension and finish, not trying for any absolute size, just all the same. all went well.
get out the vernier caliper and measure. parts are within .010 or so. I'd like better, but I can live with it. Now a little head scratching... measure the template guide, figure the diameter of the router bit, the diameter of the mill cutter, the size of the hole I want to end up with... come up with some numbers to use at the handwheels of the mill... clamp up a scrap of ply.... plunge the mill cutter and start counting turns on the handwheel.... simple shape... somehow I get it wrong the first 2 times, but finally the third try yields a template that produces a nice tight fit.
I could have made a template that indexed from the previous hole, but for this one off setup I laid out the pattern on the material and positioned the template by eye. the sticks seat top and bottom and lie at about a 10 degree bias to the face of the cabinet, so I made my template with a lip on both sides so I could turn it over and use it to cut both left and righthand sets. unfortunately, this made it so I couldn't get a plunge router in there- the lip got in the way if the big base. I used a laminate trimmer and tipped it in to plunge the start cuts, which was a bit hairy. I'll do it differently if I make another one-perhaps a lip/ fence thing that indexes via pin holes....
Bridger