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Lonely Raven · 8th November 2009

Now for the fin jig.

So these fins are going to fit together like a giant tic-tac-toe grid. The best way to do this would be to cut consistent and accurate slots 1.75" into each fin, then the fins would interlock together. If I'm off on these cuts, the tiles won't fit!

So along comes the fin jig. Typically this type of jig is used for making finger joints for building boxes or cabinets. I came up with it while teaching myself to make guitar speaker cabinets as a teen, only to find out woodworkers had been doing this for probably a couple hundred years.

The way this jig works, is that you mount a board to the miter (I used the same miter as before), then you take the 1/8" saw blade, and run it completely through the board at the correct height. This gives you a clean cut, exactly as you want it on the fins. Then I measure 1" exactly to the right of the blade kurf, and make a second cut. In the second cut I glue in a 1/8" "key". So, now that everything is set, you make the first cut on the fins by pressing it up against the "key". This gives you the correct spacing so you have 1" from the end of the board to the first cut (this is assuming your fin ends don't slot into the frame on the diffuser!!). Then you take the cut fin, and slide the cut OVER the key, which gives you the exact 1" spacing you need for your next slot. Then cut, move and repeat till you get to the end of the board! It's that simple! In fact, I was cutting 10 fins at a time using this method. It was hard on my hands, cutting, pulling, moving over one slot, cutting, pulling moving over one slot...but the end result was so accurate, that the 1" tiles I cut fit inside the assembled fins perfectly!!

8th November 2009	#3
Lonely Raven Gear maniac Join Date: Nov 2009 Location: Bolingbrook, IL Posts: 230 Thread Starter	Now for the fin jig. So these fins are going to fit together like a giant tic-tac-toe grid. The best way to do this would be to cut consistent and accurate slots 1.75" into each fin, then the fins would interlock together. If I'm off on these cuts, the tiles won't fit! So along comes the fin jig. Typically this type of jig is used for making finger joints for building boxes or cabinets. I came up with it while teaching myself to make guitar speaker cabinets as a teen, only to find out woodworkers had been doing this for probably a couple hundred years. The way this jig works, is that you mount a board to the miter (I used the same miter as before), then you take the 1/8" saw blade, and run it completely through the board at the correct height. This gives you a clean cut, exactly as you want it on the fins. Then I measure 1" exactly to the right of the blade kurf, and make a second cut. In the second cut I glue in a 1/8" "key". So, now that everything is set, you make the first cut on the fins by pressing it up against the "key". This gives you the correct spacing so you have 1" from the end of the board to the first cut (this is assuming your fin ends don't slot into the frame on the diffuser!!). Then you take the cut fin, and slide the cut OVER the key, which gives you the exact 1" spacing you need for your next slot. Then cut, move and repeat till you get to the end of the board! It's that simple! In fact, I was cutting 10 fins at a time using this method. It was hard on my hands, cutting, pulling, moving over one slot, cutting, pulling moving over one slot...but the end result was so accurate, that the 1" tiles I cut fit inside the assembled fins perfectly!!