# need help making "cross halving joint" or "half lap joint"



## grace123 (Nov 2, 2010)

I need to repair a picnic table. The legs were made of 2×4. They cross making an X and I believe the joint is called a cross halving joint or a half lap leg joint. Can someone tell me how to make this joint with a router?


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## crank49 (Apr 7, 2010)

I lay one 2×4 over the other and position to get the angle I need. Mark both pieces, then separate.

The next step could involve a router I suppose, but I prefer to set my circular saw to cut a 3/4" deep kerf and then make about 8 cuts across the space I want to remove, right up to the lines I just marked and a cut about every 3/8" to 1/2". Then I just knock the waste out with a hammer and dress it up with a chisel. I could normally be done before I could get a router out of the box and get a bit in it and get the workpiece clamped down.


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## lew (Feb 13, 2008)

I think I would make a jig that would "trap" the router base. Something like this-










The distance between the jig sides would have to be determined by the diameter of your router base and the exact width of the leg material. You will have to make the half laps in several passes so as not to remove too much material at a time.


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## nailbanger2 (Oct 17, 2009)

Crank is right on about the fastest way I can think of, of course the router would be cleaner. If you go the circular saw route, you may want to wedge the saw's blade guard open, it will tend to fight you. I say this expecting to get killed by the safety police. I have no idea of your equipment or experience with that equipment. Do not do anything that you feel is unsafe.


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## jusfine (May 22, 2010)

Nice disclaimer, nailbanger… 

I can't talk, in my framing years, I constantly had my guard wedged up on my Sawcat (with a brake) when cutting rafters.

I would recommend Pat Warner's video where he shows a number of jigs to use with a router, including an especially simple one for the half lap joint which makes them perfectly.

All the Best!


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## Loren (May 30, 2008)

I'd do it with a circular saw to define the sides and knock out the
middle with a chisel. Much faster than messing around with a router
to remove the waste. You can use a router to flatten the bottom
and that's pretty fast and what router planes used to be used for.

You can also saw the sides with a handsaw.


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## grace123 (Nov 2, 2010)

Thanks very much for all the responses. My table saw is currently out of commission which is the reason for the question regarding a router.


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## BlankMan (Mar 21, 2009)

This is the perfect example of why I've always had a RAS and still do.  Even while everybody said the miter saw killed the RAS. LOL


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## cloakie1 (May 29, 2011)

i would use the compound slider myself…very quick…..but as blankman said a radial arm with a dado head on it….now we are talking fast


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## OldMike (Mar 4, 2007)

Curt is absolutely, right on the money. The half lap, and a lot of BIG joinery, is drop dead easy on a RAS, and the reason I never got rid of my Delta turret saw.


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