# How to Use Rockler 61886 Finger Joint Bit



## gdonham1 (Oct 31, 2011)

I have a Rockler bit 61886. It is a finger joint bit but I cannot find any instructions for how to use it. I bought it a few years ago at a clearance sale at Rockler. I have a need for some finger jointed lumber and want to use it. Attached is a picture.

The puzzling thing about the bit is at the top is a square 1/4" cutter. I have not used a finger joint bit before but I thought you ran part A through the bit then used a spacer or adjusted the bit down/up and ran part B. The square cutter is used for something but I cannot figure out what. There is only the one bit and not a pair like cope and stick cabinet door bits.

If anyone knows how to use this I would appreciate the help.


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## Nickp (Dec 4, 2012)

Couldn't find it in Rockler but Amana's bit looks exactly like yours...

it seems you would cut the first piece and the second piece is cut upside down. If the cutters are spaced properly for the size of the wood, the 1/4" cutter makes a complimentary cut on each of the pieces.


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## gdonham1 (Oct 31, 2011)

Thanks,

I found a video on youtube.com about the Infinity Tools Finger Joint Bit. It explained that you reorganize the bits according to the height of your wood. You run one side up and then turn the second piece with the opposite face up. This is how you get the ends to match up. The nut on the top of the bit is removed and you restack the bits and do some testing and fine tuning, then run your production work. 

I have a lot of reclaimed oak from a church furniture factory. A lot of it is glued up with 4/4 pieces to be seats and pew bench ends. I have resawed a lot of it and run it through the planner and got a lot of 7/8" four to six inch boards that are from 28 to 14 inches long. . I have a project to make and want to use this material to make longer boards. 

Mystery solved. Thanks for your help


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## Nickp (Dec 4, 2012)

Excellent...good luck... @gdonham1

...have you figured how to finger joint the 4-6" boards...or another mystery...? 

Maybe a different joint method...? Here's an article that might give you some other ideas... https://www.woodmagazine.com/woodworking-tips/techniques/joinery/end-to-end

After you join them, might you need strength if used horizontally...? like shelves...?

What are you making with the jointed boards...? That might drive which (or better) joint to use...

...just thinkin' out loud...


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## Stick486 (Jan 4, 2013)

> ...just thinkin' out loud...



move to the head of the class...
stagger the FJ's and edge spline..


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## gdonham1 (Oct 31, 2011)

Thanks forr your replies. 

The finger joints for this project will work best. I have milled the boards to 7/8" thickness. I will trim all boards to 4" wide and then finger joint them together. After I make the longer boards I will then glue two layers together and of course stagger the finger joints. I need four boards that are 4" x 52" and eight 4" X 33" and a few other pieces. So in the end I will have two 7/8" thick boards glued up and the finished dimension of the boards will be 1.75" Thick X 4" wide X 52 Long". 

The reason for this is most of my lumber is reclaimed and are 12" to 24" long. The finger joints will allow me to make longer boards and laminating two of them together will work like segmented bowls, staggering the finger joints will make it very strong.

Since I have so much of this lumber I need a practical way to make longer boards. I will most likely not do any edge gluing but the finger joint bit makes that work pretty good for alignment. So if I need to make some panels I can finger joint the ends then edge joint after trimming the boards and make wide panels if required. 

After I make the end grain finger joints I will run all boards through a drum sander to clean up any variations, joint one edge, then trim to a uniform width on the table saw. 

Yes it is a lot of work but the project I have in mind will be worth the effort. 

Thanks for your advise and help


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## Nickp (Dec 4, 2012)

It certainly sounds like you got it all together...best success with your project...would love to see what you end up with...

Didn't mean to bombard you with all the questions...


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## Cherryville Chuck (Sep 28, 2010)

If you stagger joints then you don't really need to joint the ends like that. The double thickness lam should be strong enough for short lengths. In longer lengths or when bending lams to make ribs you have to make scarf joints which is a tapered lap. I tried making ribs for tarp covered buildings once. On 3/4" thick lumber the scarf joint had to be 9" long.


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## gdonham1 (Oct 31, 2011)

I found instructions on Infinity Tools website and for Amana. I got the bit working today. At first I rearranged the cutters so I had two of the little cutters and the big one on top. I got it to work but had a lip at top and bottom. I figured out that I needed three of the cutters and the large one and the problem was solved. You would have to rearrange the cutters for your particular thickness of wood. I had 7/8" thick. The cutter is a little picky but once I got it dialed in it went like clockwork. I used my coping sled that is usually used with cope and stick router bits. The coping sled held each piece very well and I got the height all set up and replaced the backer board and go no tearout or fuzzies. So far so good. Like many bits, 45 degree lock miter, and others, there is a lot of fussy setup. Once you get it set up things work well. It is just frustrating to get to the perfect setup.

One thing I did learn is you run one end, part A through the router, then you run the second board, part B, and place the A cut on the table and turn the B cut over and slide the two together. If part B is above part A then you move the bit down. If the opposite is true then you move the bit up. I have a Jessum FX router lift and the crank is calibrated to 164" increments.


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## Nickp (Dec 4, 2012)

Excellent, Guy...like eating an elephant...one bite at a time...


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