6 Piece Burr Puzzle Router Jig

[BozInOz]

Recently I've made a few 6 piece burrs as presents. I thought it was a nice way to practice some technique and quite fun to make and challenge people with.

My lovely wife thought this was great and she wanted some to give some away. Only problem was it takes me about 2 hours to make one.

So I made a jig.

Pics are pretty explainatory. 10mm router bit, extending into the jig 16mm (6mm MDF, 10mm pine) Triton router table with fence moved back and fixed.

Action is simple. Piece in. Spacers as needed. Slide it through using fence as guide. Cuts a 10x10mm hole into the 20x20x60mm pieces of wood. (I used jarrah, blackwood and maple). A bit of sanding, a bit of oil, and presto.

Limitations. Obviously can't do notched pieces, you'd still have to chisel part of it out. I used a piece of pine to hold the work horizontal but downward pressure upgrade needed.

Burr designs from http://www.research.ibm.com/BurrPuzzles/

[les88]

Jig good idea I like the puzzles too
les

[Chipman]

Only 2 hours! you are a fast worker...well made and nicely presented

Chipman

[keju]

Those look fantastic! I'm with Chipman..... the presentation is really nice!

I'm not confident using a router.... so when I made a 3 piece burr puzzle I did it with the scroll saw. I'd think maybe using the scroll saw to cut the notches might be quicker and easier then using a chisel?

Juvy

[BozInOz]

Well the wife has to get the credit for the presentation. I was going to have the 6 blocks next to each other with those instructions printed to size. It's good for the person to see them together, otherwise, they tend to think it can't be done.

Scroll saw is not a bad idea. I've never really got into scroll saws. It may be hard to get perfect 90 degree square cuts.

[keju]

Shouldn't be much of a problem to get 90 degree square.... you should have the saw perfectly square at all times anyway ( well unless you do a special kind of cut) ... that's easy accomplished with help of a block.
The other thing is to be careful not to press too hard or you push the blade out of square..... but for this particular project you could use a decent size blade which makes that much easier.... just cut in to one corner, back up.... cut into the next.... then I'd go into the middle and turn to reach the end of the first cut... perfect corner... then cut to the other side... three cuts is all it takes. If you try to turn in the corner you risk rounding them.
You don't even need a pinless blade.... you can do this with any of the pinblades too.

In case anyone's interested.... here's the 3-piece knot....
http://www.wood-line.de/G/G000801.htm


Juvy

[BozInOz]

I know this post is a little old.
However I was asked today to explain how the jig works so I've posted some intructions on my blog.

Burr Jig Instructions @ The Love of Wood