Infinity Lock Miter Master Jig

[Patrick Varley]

Not sure if others have come across this, but I picked one up on a whim and I have to say it's $30 well spent

https://www.infinitytools.com/lock-miter-master-jigs

I've been messing around over the last few months on the router table testing out different methods for drawer boxes, keepsake boxes, etc. Was interested in trying some lock miters and came across this. I know there are setup blocks, but I liked that this method would work for essentially any thickness (even if it was non-standard), and can help setup offset joints. Also nice that it works with other brand bits.

Broke it out this weekend, and cut a nice fitting joing on the first try. Can't beat that!

[Mike Burke]

I have been thinking about trying this kind of router bit for making Stickley style legs. Thanks for posting.

[Rich Engelhardt]

IIRC, the inventor of that bit is a member here.

(P.S. They do work so easy even a fumble fingers like me can use it and get great results)

[Dave Sabo]

FYI

The set up jig works on bit other than infinity too.

[Dave Zellers]

IIRC, the inventor of that bit is a member here.

Yes indeed.

Adam Shaffter. IBox as well.

[Kris Cook]

Funny coincidence. Just ordered one of their bits and the jig last night. Hadn't seen this post before that. The video on their site sold me (that and actually having an option for expedited shipping )

[Dave Zellers]

Well I certainly made a mess of that. It's
Alan Schaffter.

And to be more precise he didn't invent the bit but the set-up jig.

My bad.

[Rich Engelhardt]

Arg...that's correct - I made a huge mistake. He invented the setup jig - which is worth it's weight in gold.

[Dave Zellers]

Yeah we both dropped the ball on that one.

But for those in the market for one, I'd be careful- Gold today is $1911 an ounce.

[Joseph Montroy]

Does anyone know if the jig will work with the infinity lock miter shaper setup?

[Patrick Varley]

Does anyone know if the jig will work with the infinity lock miter shaper setup?

I have not done it personally, but the instructions say that it is possible though the setup may be slightly changed depending on your cutter (p. 14): https://www.infinitytools.com/amfile.../product/3322/

The Q&A for the Infinity lock miter shaper head also has a reply from Infinity which says it should work. Specifically notes it will not work with cutters that use inserts, though.

I've had good experiences with Infinity customer service, which would give me a bit more piece of mind to try it out.

[Joseph Montroy]

Thanks, Patrick. That's great advice - I'll give them a call!

[Ernie Miller]

Actually his first name is Alan - very inventive guy!

[Ken Krawford]

How does this bit work with plywood? I assume it's like any other router bit - the sharper the better.

[Alan Schaffter]

test, to see if I can still post.

Well I guess I can. Thanks Ernie.

I used to spend a lot of time here but haven't been around in quite awhile. Yes, I am the inventor of the Lock Miter Master. My name is on the patent which is now owned by Infinity. I still get a small royalty.

As to the capabilities of the LMM- it can be used without special procedures with almost every brand of lock miter router bit except ones that have cutter geometry similar to many shapers. The LMM is designed to work with bits whose cutting edge is a radius of the cutting circle. Some router bits, especially those with replaceable carbide inserts, and many shaper cutters, have cutting edges that are chords of the cutting circle. While the LMM can be used with these, the procedures are more complex. Worth it??? As mentioned, this is discussed on pp. 14 of the instructions.

There is a heavily illustrated set of online (and downloadable) instructions on the Infinity website at the link posted above by Patrick. I believe Infinity has a video on their website as well and there are tons on Youtube- those vary in quality and understanding of the principle of lock miter bits and how the LMM works. The instructions provided with many (most?) lock miter bits are generally wrong and often devolve into frustrating trial and error. With just a little be of care you can set a lock miter bit with the LMM and achieve a perfect fit on the first try!!

One statement I hear a lot is that a lock miter bit can not be used to join stock with different thicknesses- that is totally incorrect. Also, I don't believe any of the videos discuss the extra reference marks on the LMM. I put them there to be used to create single and dual offset lock miters. (discussed in the instructions). There are times when such joints may be desirable.

While not as fancy or complex as a CNC or Pantorouter, my other invention, the INCRA I-BOX jig for making box joints does a fantastic job making box joints, dentil molding, etc. of almost any finger width and it can be used on both a router table with a straight or spiral bit or table saw with a dado blade. Many prefer the table saw because of speed and reduced chance of chip out possible with a router especially in ply.