# Cutting deep cross lap / cross halving joints



## BFamous (Jan 26, 2018)

Greetings all.
Opinions wanted. I'm building a set of cubbies (roughly 6' wide x 4' high) that are going to be about 8" deep. In doing so, I'm thinking of using cross lap / cross halving joints (not certain which term is actually preferred). This cubbie is going to have 24 cubes in it, so three horizontal boards and five vertical boards - so a lot of cross lap joints.

I'm planning on using 1/2" plywood for all of these pieces. 
So here's my question. To make things easier and quicker, my current thought is to clamp and tape the 5 vertical boards together face to face, then standing on edge, run them all over the table saw blade set at 4", then slide the wood 1/4" and make a second pass to cut the other side of the joint. I could then knock out the waste with a chisel.

Does anyone have any other methods they think could be easier, quicker, or more precise for creating that many joints at that depth? Or a different idea on a better way to construct the cubbie instead of cross lap joints?

Thanks!


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## therealSteveN (Oct 29, 2016)

> So here s my question. To make things easier and quicker, my current thought is to clamp and tape the 5 vertical boards together face to face, then standing on edge, run them all over the table saw blade set at 4", then slide the wood 1/4" and make a second pass to cut the other side of the joint.
> 
> *Works great on some 12 inch table saws. On my General 350 a 10 inch saw I get a little over 3" max depth of cut.*
> 
> ...


If it were me, I'd look into a jig that would allow me to run a router in, and out with a 1/2" bit. Cleaning the corners would be the dicey part. Maybe a jigsaw with a smooth cutting plywood blade.


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## BFamous (Jan 26, 2018)

Thanks Steve. I had similar thoughts about the chisel on plywood - but figured the parts where it was rough would be hidden inside the piece lapping over it…

I was also thinking of using the bandsaw to cut the sides, but moving 6' pieces on my bandsaw table isn't something i really want to do.

Thought about the router and a jig, was debating that method doing 2-3 passes on each. As for cleaning it up, wouldn't the arch be hidden by the lapping board?

Also thought about just doing dados on the horizontal boards and cutting all of the vertical supports. Wasn't too crazy about the dados back to back on 1/2" plywood, even if they were just 1/8" deep. Would provably need to bump up to 3/4" ply…


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## bandit571 (Jan 20, 2011)

Hmmm…









And..









Done on the bandsaw, cleaned up with a chisel….


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## Lazyman (Aug 8, 2014)

If you have a bandsaw, that would be easier, though it will depend upon how far from the end you are able to cut with your bandsaw. I've never seen a 10" table saw that can cut to 4" depth? You could cut to whatever the max depth is and then finish with a hand saw or jigsaw. Then use a coping saw to cut out the waste and clean up with a chisel. If your coping saw cannot handle the max depth, you may have to cut the waste out in 2 steps.


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## LeeRoyMan (Feb 23, 2019)

I would just use my sled on the table saw with a dado blade.


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## Lazyman (Aug 8, 2014)

I've used a dado blade to do that with narrower stock but with the max dado blade being 8", plus the addition of the thickness of a sled, you'll be lucky if you can cut 3" deep.


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## LeeRoyMan (Feb 23, 2019)

I'm laying them flat.


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## MadMark (Jun 3, 2014)

As has been mentioned 10" table saw can only cut 3" or so, need 12" TS to get to 4". Beyond 4" TS isn't viable.

Dado leaves radius depth at end of stopped cut. Dado sets are generally 8" so their max depth of cut is just 1". Stopped cut will *look* sloppy as blade curve will show. Joint will *be* sloppy as end of slot will be tapered instead of square and pressure will make the joints move inward.

Band saw throat isn't deep enough for crosscut on 6' long boards.

Drill holes in all pieces at once and cut in 4" (or more) slots with hand saw. Drill hole reduces/eliminates need to chisel out ends. Drill and cuts can be made stacked. Could be done with jig saw or scroll saw but would be tedious and cuts won't be perfectly straight vs hand saw cut.

Alternately an open (no fences) router table with miter gauge & stop block can make consistent 4" (or deeper) slots in 6' 1×8 pieces.

M


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## bandit571 (Jan 20, 2011)

Millers Falls Langdon #75. Saw has a 5" depth of cut. Stand the board up on edge, clamp to the fence. Make 2 cuts. How ever long the board is, will still fit. Make the 2 saw cuts, setting the depth stops as needed. After the two cut per joint are done, couple hits with a chisel the same width…will pop the waste out, leaving a square end.

Can clamp a board to the mitre box, so the 1/2" plywood can slip by. Make a cut, slide a bit, make second cut. Slide again to the next two….30" long saw plate…cuts will be quick. And..very quiet.


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## LeeRoyMan (Feb 23, 2019)

8" dado blade will cut 2" 
I just took 10 minutes and did this. 
Here's both sides of the cut.


















Here are the two pieces put together. Nice and tight nothing sloppy and no curved end cut shows.


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## Kazooman (Jan 20, 2013)

Wow, LeeRoyMan! You sure use some really fine plywood when you want to do a demonstration! Very imoressive. The joinery looks nice as well.


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## MadMark (Jun 3, 2014)

You don't see that 1" long ramp on the one side? The edge isn't a taper? Put two together and rap 'em with a mallet and the edge of the back will curl and the joint will shift. Thanks for the perfect example of the issue.

M


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## LeeRoyMan (Feb 23, 2019)

> You don t see that 1" long ramp on the one side? The edge isn t a taper? Put two together and rap em with a mallet and the edge of the back will curl and the joint will shift. Thanks for the perfect example of the issue.
> 
> M
> 
> - Madmark2


sure! lol
Go drill your holes and use the hand saw and show me a better joint then.

enough said!


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## Kazooman (Jan 20, 2013)

LeeRoyMan: your high quality plywood demo is only surpassed by your stress test video. Good work and thanks for a good chuckle.


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## ColoradoJake (May 14, 2019)

> enough said!
> 
> 
> 
> ...


That was is an excellent video, I did not expect that. Thank you for the fun and showing me that I would not have to clean out that last bit of the cut. I guess it would perhaps be an issue if only one piece was hit with the other piece not being supported, but that is not likely to happen.


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## LeeRoyMan (Feb 23, 2019)

I built these in the late 70's using my radial arm saw and a dado blade. 
(Same lap joints as above) All the cuts were at a bevel. Lefts and rights. 
You think that was confusing….on a radial arm saw?.... yes!
LOL, a blast from the past as they say.


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## therealSteveN (Oct 29, 2016)

Looking like a Hippy LeeRoy. Are those for wine bottles?

I think I'd still stick with a router. You'd be faster though. Gets to being 6' long I start becoming a bring the tool to the work kinda guy, unless they are straight rip cuts, jointer, or planer runs.


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## SMP (Aug 29, 2018)

I had the same dilemma on an earlier project. I ended up just cutting a shallow dado in the horizontal pieces that the vertical pieces could slide into. Then it was just a matter of making a bunch of the same sized vertical pieces. Kind of like how those part bin containers or drawer organizers are setup.


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## Tony_S (Dec 16, 2009)

> enough said!
> 
> 
> 
> ...


THAT… was friggin awesome


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## LeeRoyMan (Feb 23, 2019)

> *Looking like a Hippy LeeRoy.* Are those for wine bottles?
> 
> - therealSteveN


I did mention it was the 70's right? lol 
Yeah, wine bottles.


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