Wooden Jack Puzzle (6 piece burr)

[RedShirtGuy]

Finally!!! I've made something I'm not entirely disgusted by and am willing to show.

It's a very, very basic 6 piece burr puzzle from here (http://www.almy.us/puzzle.html) that I've designed my own router jig for...which is probably the bit I'm most pleased with.

The pieces aren't finished but I'm so happy that something finally went right this year that I wanted to post the pics anyway.

The jig runs along a mitre slot so there's no setup or adjusting to be made other than the height of the bit (6mm bit x 6mm high). The workpiece goes between the two edges and is adjusted with the two spacers which are used one at a time to push the workpiece along so I don't have to change bits to clear out the bigger areas. The spacer that isn't being used in the jig slips into the other end to push the workpiece against the left end of the jig.

The jig could do with a bit of refining so it pushes the workpiece down harder and as can be seen in the last image, it's not quite as tight as I'd like it (although it still does take a bit of pressure to get the pieces together).

I've got to figure out why the cuts are tearing so much (single flute bit rather than double?), but otherwise I'm pretty happy with how everything has come out. It only takes a few minutes (maybe 5?) to route the cut pieces (I did a jig for my SCMS to do this too) which was the real goal of all my faffing around...to make it quick and repeatable.

[ShazL]

That looks great! Well done on making you're own jig. I'm still only up to straight cuts on the router and have just made my own straight cut jig for the circular saw.

Happy woodworking :2tsup:

[munruben]

I've got to figure out why the cuts are tearing so much . Do you back up the piece you are routing with another piece of timber, this should prevent any tear out. I like it, great job. I think they are fascinating. Well done.:2tsup: BTW, I think your little jig is great.

[artme]

:2tsup::2tsup::2tsup:

[RedShirtGuy]

Do you back up the piece you are routing with another piece of timber,

The workpieces sit in the middle of the jig quite tightly and the whole thing passes over the router bit. I thought that would have been enough backing up but I guess that the channel for the cut in the jig has probably been enlarged from so many passes. It would only be .5-1mm bigger, but maybe that's enough to cause the tearing.

I was also taking out a depth of 6mm in one shot so I think next time I'll have a crack at doing a couple of 3mm passes per cut and see how that goes.

I've also been thinking of redoing the jig so it can take a full load of 5 pieces so I can make a whole bunch of cuts in one pass just to speed things up a bit more. There's nothing like procrastinating on doing work by making uber-jigs :p

[watson]

If you were thinking of two 3mm cuts, may I recommend that you do this by setting the bit to 6mm above the jig base and then adding a 3mm insert into the jig and cutting with that in place, then remove the insert to make the full depth cut. That'll make sure you avoid stepped cuts caused by raising the bit between cuts.

[RedShirtGuy]

Clever breeches Watson. Consider it done. Ta :2tsup:

[bpj1968]

Perhaps cut 1/2 way through then cut from the other side. Start on the other side of the bit and pull it towards you to make a small first cut, then lift it over the bit and finished in the normal direction.

[Mr Brush]

Actually, this job is a perfect application for the:

YouTube - KM-1 KerfMaker by Bridge City Tool Works

Used mine the other day to cut some slots for shelves, and it makes life very easy. A very nice little gadget.....:2tsup:

[Mr Brush]

Yes - the joints really are that tight !

I've got into the habit of adding one thickness of paper to the timber I am gauging up with the KM-1, the resulting slot is then more of a nice sliding fit :2tsup:

Could be used on the router table too; you'd just set the KM-1 to whatever the 'kerf' of your router bit happens to be (from a test cut).

[RedShirtGuy]

Get me one or the kitten gets it :dev:

http://3.bp.blogspot.com/_ahIy1udbZ9M/SKCKiWavZ9I/AAAAAAAAAJk/5OA_UFA72Sk/S660/cute+kitten.jpg


That thing looks awesome!!! So easy to setup and use, and produces fantastic looking joints. Thanks for the heads up.

Did you get yours from Bridge City or somewhere else? (They're $72 USD btw for those that haven't chased it up)

[Mr Brush]

LOL - great pic :D

I got mine from Bridge City direct. A painful company to deal with, but worth it in this case. I seem to remember that there are a few ideas out there on the interweb for making your own? Anyone???