Replacable Insert Throat Plate
I've been wanting one of these for a long time:
That's the insert with a replacable insert (what I call an oak insert insert) that Norm has had for some time. The guy that makes (made) them doesn't appear to be marketing them any longer and has the business up for sale.
I always thought they were a little pricey and longed to craft one of my own for some time. Can't be too hard, I thought, and it wasn't.
The first thing you need is a source for ˝" thick aluminum plate. I'm very fortunate to have an excellent scrap aluminum yard nearby and got some stock. I don't imagine I have to show you a plain old piece of aluminum plate, so I'll jump right to an interim shot.
After rough cutting the plate into the general shape of an insert (band saw, table saw), I spent some time filing and fitting, filing and fitting, filing and fitting. Eventually, I wound up with a blank plate (center, left). I also used my jig saw and drill press to size the finger hole, and finished it up with a roundover bit in my trim router.
A little layout time (to make sure they were located properly), and a trip to the drill press yielded the pilot holes for the adjusting set screws you can barely see here.
The insert at the top is the OEM insert which came with the saw. It still has its uses. At the bottom is one of the Baltic birch inserts I've made (I have probably a half dozen in inventory).
I'm sorry you're going to be disappointed that I don't have any live shots of the machining. Suffice to say there were several sessions at the router table.
The insert here is a piece of walnut. It just happened to be an already thicknessed piece at hand and I was in a hurry once I had the dovetail groove ready to get something in there. Eventually, I suspect I'll use a piece of maple, birch, or ash. To follow Norm, of course, I could make one of oak, but it doesn't really strike me as the appropriate zero clearance insert wood.
Incidentally, I agonized for some time over the angle to use for the dovetail. My first thought, naturally, was the
traditional 14° used in the dovetailing jigs. Then I thought 45° would be better. Finally, not having a 45° bit, I opted for 14° and in retrospect, there shouldn't have been any question. It's just right.
Not quite so visible are the enlarged and tapped holes for the adjusting set screws. I'm so pleased. This thing sits in its place rock solid and with a satisfying heavy metallic "clunk" as it goes in.
Here is a view with the insert removed so you can see the machined substructure. With the exception of a plough cut with an 8" blade in the table saw to establish the initial groove, all of the machining was done on the router table.
The through openings in the plate are essentially the same as the OEM insert, so I may be able to fit inserts for miter cuts as well, although probably not for a full 45° angle. Still, I did make a BB insert for 45°, so I'm covered there.
The through openings will also accommodate the OEM splitter/guard and an aftermarket splitter, so long as I cut the insert at the back for clearance.
Incidentally, and completely off topic, I just HATE that I can't use HTML when posting here. What's up with that? This looked so much better with some layout as I applied it over at WoodCentral.