Cool box joint jig

[tfischer]

Dave's thread about his box joint jig got me doing some googling on the subject, and I ran across this very cool shop-built jig with a ratcheting indexing system. Has anyone here built/used this jig? Any thoughts on how to adapt it to use the SMT vs the miter slot? I can use the slots if necessary, I have them on both sides of the blade, but typically prefer the SMT.

http://www.ibuildit.ca/Workshop%20Pr...ced-jig-1.html

[tfischer]

No comments? Guess this isn't as unique as I thought it was

[LCHIEN]

No comments? Guess this isn't as unique as I thought it was

I had a few thoughts, but unfortunately there's not the complete plans to look at in enough detail - they want you to buy the plans.

So anyway here's my questions and thoughts:

Usually the tightness of a box joint can be adjusted on a very fine scale by changing either the cutter width or the finger width... usually its way more convenient to change the finger width because the cutter (router) is fixed or you have to dismount the blade which also dismounts the jog which changes the finger width. So almost always you change the finger width and in most box joints this is done by moving the jig to either side.. But here he permanently attached the miterslot guide so it not movable and the ratcheting index seems to be fixed to a precut piece of wood inside the jig so its not adjustable. And the accuracy of the index seems to depend upon a series of cuts which must be initially very accurate. So I don't see how you make the all-important tightness adjustment.

Another thought was what keeps the blade from chewing up the index mechanism if you push it too far??? Looks like the mechanism is elevated so normal blade height won't hurt it.

Finally, jigs are easily transferred to the BT3 SMT by attaching the back of it to the front of the BT3 miter fence. Here, though, the back is got a strange angle I'm not sure what its for on the back left side.

Got a lot of moving parts... Generally we like to think of jigs as having few moving parts as possible.

[Black wallnut]

My thoughts on box joint jigs are that the router table is easier. This page details what I use. I done lots of box joints and this method works for me. That said Tim your linked jig looks really cool, overkill, but cool. A simple spacer fence jig takes less than 10 minutes to make. Setup no matter what jig is a test, adjust, retest thing.

[tfischer]

My thoughts on box joint jigs are that the router table is easier. This page details what I use. I done lots of box joints and this method works for me. That said Tim your linked jig looks really cool, overkill, but cool. A simple spacer fence jig takes less than 10 minutes to make. Setup no matter what jig is a test, adjust, retest thing.

Good advice. This isn't "my" jig (yet anyway). Just thought it was cool how it can work with different spacings, etc (at least in 1/4" increments). In the one video he takes a brand new jig, sets it up on his saw, and makes perfect joints without any tweaking at all.

Plans are $9 and doesn't seem like it would cost that much in materials.

[tfischer]

Loring - he has instructions for a jig to make the indexing piece. It indeed has to be very accurate.

If one were to attach it to the SMT then you'd have some side-to-side adjustment play...

[Black wallnut]

Good advice. This isn't "my" jig (yet anyway). Just thought it was cool how it can work with different spacings, etc (at least in 1/4" increments). In the one video he takes a brand new jig, sets it up on his saw, and makes perfect joints without any tweaking at all.

Plans are $9 and doesn't seem like it would cost that much in materials.

I guess I wrote my reply poorly. I know it's not your jig, yet? It's neat and impressive that he just mounts it and starts cutting without adjusting. In a way it is like my SMT mounted tenon jig; it is overkill but nice.

Building elaborate jigs has been for me just as rewarding as building projects. It is shop time.