Rabbets on end of plywood help needed

I don't know how you would do it with a router, but here's your rabbits.

Uh, that wasn't rabbets you meant, was it?

The Devil is in the details.

Glad you decided to join the fun. An edge guide is good for a dado, but for a rabbet, I would use a straight edge clamped to the long end, spaced so when the router's base rides against the straight edge, the bit bites into the ply exactly the width of the desired Rabbet. You can use a straight bit for this, but a 3/4 inch long mortising bit cuts a beautiful flat bottom. I'd do this in several passes, with the last one only shaving a slight bit of material for the best possible glue up finish.

With ply, the end grain really sops up the glue, so put two coats of glue on the end grain so it really fills all the nooks and crannies.

When you do this, mark the edge of the router that will ride against your straightedge. Otherwise you could rotate the router and have an uneven cut and a nasty surprise at glue up.

Here's a diagram of a bit with bearings showing the difference between top and bottom bearings, something that occasionally confuses me.

I did this with dado blade on the TS. Can this be done with a router and how?

First I did these with the TS and Dado blade setup but took a lot of setup time only to find was too tight fit, so I used the bit sized for plywood. Any tips how center the bit when making the cut "X" inches from edge.

Still need to do face trim.

Here's a rabbeting bit and a mortising bit. Rabbets are rarely wider than the thickness of the piece you're glueing into it. The rabbiting bit has a bottom mounted bearing you let ride against the edge of the wood. You can get them with several diameter bearings and change them out. Using an edge guide and the mortising bit, you take a scrap of the material and lay it on edge where you want the rabbet. Use it to scribe a short line on each side of the piece you want to rabbet. Lay a straight edge (the factory edge on a half inch piece of MDF for example) from scribe mark to scribe mark. Your mortising bit's bearing will roll on that edge.

Plywood is not 3/4 inch thick anymore, it is not 18mm, slightly thinner. So your bit should go no deeper than about half that thickness. You can see that a 3/4 diameter mortising bit will remove the entire rabbet area just fine.

Dados and grooves are another matter. You can buy an 23/32nds plywood bit just for that purpose, but there is no guarantee that any particular piece of plywood is exactly that thickness. So for a dado or groove, you are much better off using a half inch bit as suggested and an exact width dado jig as in the video. They are pretty easy to make. Here's a drawing.

You fit a piece of the material that will go into the dado or groove between the two horizontal boards and use the star knobs to cinch tem down. Clamp the jig securely in palce and begin to do the routing. A half inch straight bit will work but I'd go right back to a half inch mortising bit for this. The top mounted bearing will ride on the side of the rails as you slide the router first one way, then the other. One important feature of mortising bits is that they cut a really flat bottom groove, rabbet or dado.