Lock Miter Router Bit Questions

[Dave Sabo]

The infinity setup gauge is quite helpful, but it’s not foolproof and not quite plug and play either.

That said, it’s better than a setup block because it’ll work on any bit with any thickness material. The matched setup blocks only work for that bit and thickness. As already mentioned , consistent and accurate stock prep is crucial for the Infinity jig too.

You’re still likely to have to tweak the fence with the infiniTy jig to get a perfect joint, but it will get you there quicker and with less test cuts.

[Mel Fulks]

The biggest problem with this bit I that there is a knife edge that runs against the out-feed side of the fence. A sled would definitely help especially for the horizontal cut.

I have always just left a small flat instead of running to a pointed edge. Then ,after gluing and sanding , I sand the sharp corners off
by hand.

[Warren Lake]

old guys I knew just cut a mitre then put a slot in each piece then a spline. Thats how they were taught. Mel whats your thinking of sitting back a bit, that the sharp point is too delicate or.

[Mike Cutler]

old guys I knew just cut a mitre then put a slot in each piece then a spline. That's how they were taught. Mel whats your thinking of sitting back a bit, that the sharp point is too delicate or.

Warren.
The edge is definitely fragile. It's essentially a knife edge in wood. Trying to use it as the reference edge for joint doesn't work out well.
I used a carrier sled that referenced the top of the sled to the fence and table, and thus protected the edge of the miter joint. That was many years ago though.
I was making Stickley style chair legs, and costumers at that time. 4 pieces of qsawn oak, glued together to present qsawn on all four sides.They were pretty, but a pain in the butt to make.
I know the folks are making 90 degree joints with it now. I've never done that, personally. All of mine were long grain, edge, glueups in the form of "posts".

[Rod Sheridan]

Hi Joshua, once you have the bit, make your own sample block out of wood...........Regards, Rod.

[Rod Sheridan]

old guys I knew just cut a mitre then put a slot in each piece then a spline. Thats how they were taught. Mel whats your thinking of sitting back a bit, that the sharp point is too delicate or.

Hi Warren, I have that cutter for my shaper, the edge is delicate.

Once setup it works great however I'm not convinced that what I do it's worth the bother. I can simply veneer a leg blank much easier, especially since as a hobby user I'm only making a few legs.....Rod.

[Warren Lake]

Dont have a problem with the edge. Ive laid back before on it as a fair bit of my work was rounded so it gets erased anyway. If left sharp edges as well with no issue. 45 degree cutter high speed steel on the shaper cuts clean. There is more tension release on material if you rip a 45 on a saw than if you do the on a shaper. Ive done enough just 45 with no spline but good clamping block set up and it works well but more care needed. Also the folding and packing tape on MDF.

Joe has a you tube on those cutters and runs some material.

[Mel Fulks]

Warren, Yeah the sharp point serves no purpose . I leave about 1/32" ,with that I never have tear out on the edge.
I also use 3/8 round over climb cut on the inside corners to eliminate any tear out from the mitre cutter. Without that
roundover you can have big strips of wood flying off.
I've never used the router bits ,only the aprox. 4 inch diameter shaper cutter

[Dave Sabo]

once you have the bit, make your own sample block out of wood

Sure , you can do that.

But chances are you’re going to have different thicknesses that would necessitate multiple setup blocks. 3/4” stock isn’t always 3/4” exactly.

[Thomas McCurnin]

It sounds like you are joining leg parts so that QS figures are showing on all four sides. I have done this and it is a pain.

You will need multiple set up parts and multiple home made set up gauges.

I bought popular milled to the exact dimensions of the QS Oak, and used that for test pieces and set up. Adjust the bit, run the stock, adjust the bit, run the stock, get it sort of right, make a set up gauge, run the other half, realize that I was off by a 1/16th,re- adjust the bit, re-run the first piece, make another set up gauge, re-run the 2nd piece and make a trial fit. Rinse and Repeat if necessary.

Once I had it dialed with the popular, I ran the oak. Having multiple router tables with two bits would have been really nice. If you are a FWW Premium member, the technique is detailed in an article by Patrick Nelson FWW No. 121–Nov/Dec 1996.

This is very fussy work, something that I seemed to enjoy at the time.

Another way of doing this is to apply 1/16th" QS veneer and chamfering the edges. I have not used that technique, but I know it exists. If you are a member of Fine Woodworking Premium Plan, the plan is detailed in FWW Aug 07, 2012 by Gregory Paolini. It might be free since it is a video. It utilizes three QS sandwiches and two veneers covering the edge gain of the sandwiches.