# Cross dowels, 1/2 ply & jig ?s



## Redicliff (Aug 29, 2018)

I'd like to use cross dowels to join 1/2 ply.
Assume 1/4 is appropriate cd size?

But, the jig?
I find this jig on aliexpress
3 in 1 doweling jig
which looks like a knock-off of an earlier, discontinued Woodpecker's model.
or would an inexpensive jig work, such as this Home Depot offer
jig

Advise and recommendations appreciated.


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## Steve Neul (Sep 2, 2011)

The HD jig would be better for the face of a sheet where the 3 in 1 would be better for edge jointing.


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## Redicliff (Aug 29, 2018)

Steve Neul said:


> The HD jig would be better for the face of a sheet where the 3 in 1 would be better for edge jointing.


Thank you for the response.

Being an utter novice, I'm unclear the distinction you make. Are you indicting that two jigs would be necessary for a cross dowel installation. It might not be difficult to DIY something that would work. But it seems that one, angle jig would line up the cross dowel bolt hole with the screw hole.


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## JohnGi (May 9, 2019)

Are you trying to make corner joints for a box made out of 1/2" plywood with dowels? Dowel construction has some shortcomings in that orientation. 
A dowel in the edge of plywood can be very strong if the hole is deep enough (3 times diameter is the old rule of thumb), accurately sized (brad point bits work best in my experience), and well glued. 
A dowel like that may well break before it can be pulled out.
But a dowel through a piece of plywood has much lower withdrawal force. A blind dowel into one side has even less. The hole isn't deep enough, and the plywood contact is largely end grain which doesn't give as good a glue bond. A box corner joint made this way will likely work loose over time.

The dowel jigs I've seen are intended for frame, not box, corners. Dowels work much better for frames since the cross grain hole can be deep enough to get the needed glue area. The jigs give very accurate registration of the frame faces.

Do you plan to use dowels and screws, or does your last comment mean something else?


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## Steve Neul (Sep 2, 2011)

Redicliff said:


> Thank you for the response.
> 
> Being an utter novice, I'm unclear the distinction you make. Are you indicting that two jigs would be necessary for a cross dowel installation. It might not be difficult to DIY something that would work. But it seems that one, angle jig would line up the cross dowel bolt hole with the screw hole.


In this illustration the joint on the left would go easier with the 3 in 1 jig. On the one on the right where holes are needed in the face of one board the HD jig would be better there. Personally unless I'm doweling a lot of parts I don't use a jig at all. If you have a steady hand and a brad point drill bit you can just mark where the dowels go and drill it. Often jigs move from where you set them so I consider them marginally helpful.


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## GeorgeC (Jul 30, 2008)

What are cross dowels?

G


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## Tool Agnostic (Aug 13, 2017)

GeorgeC said:


> What are cross dowels? G


Like George, I am a bit confused by this thread. Here is what confuses me:

I don't understand what @Redicliff wants to do.
I am not sure Redicliff is using the term "cross dowel" as I understand it.

To me, a cross dowel is a short piece of dowel, usually metal, with a threaded hole through the middle of the dowel. The threaded hole is perpendicular to the long axis of the dowel.

In typical use, a long hole is drilled into the edge or end of a board, such as a shelf. A short hole (often a stopped hole) is drilled into the face or side of the board to intersect with the longer hole. The cross dowel is inserted in the short hole. A long bolt (screw) is put through another board (e.g., shelf support) and then down the long hole until it threads into the cross dowel. As you tighten the screw, it pulls the two boards together. See the image below.

I have seen cross dowels when I assembled inexpensive ready-made furniture for relatives. They are well suited for mass-produced flat-pack furniture, where industrial production methods assure consistent, accurate drill holes for assembly. You can buy cross dowels at woodworking stores.

Go ahead and shoot me now, but this is another example where someone has brought us the solution and we know little about the problem being solved. If we knew more about the true requirements, then we might be able to suggest better alternative solutions. 

_-> Perhaps Redicliff can tell us more about the project._ What are you building? What are the cross dowels supposed to do? It seems like you are joining the edges of two plywood boards at right angles to each other - is that right?

Here is an image of a cross dowel, which is the the silver part. The image was found from a web search. I did not look at the source site:


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## Steve Neul (Sep 2, 2011)

GeorgeC said:


> What are cross dowels?
> 
> G


It's a dowel that is angry. Actually it's a piece of hardware which looks like a short steel dowel with another hole running through the side of it that is threaded. You insert it in hole to bolt other parts to. They are sometimes used in box store shelving that is mortised for cam lock fasteners.


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## GeorgeC (Jul 30, 2008)

Thanks. Had never heard the terminology and could not figure it out based on original post.

George


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## HoytC (Dec 30, 2019)

The AliExpress jig is for Cam and Dowel connectors. Also called Camlock or Ikea connectors.










See the video here.


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## Tool Agnostic (Aug 13, 2017)

I am still trying to understand what @Redicliff wants to do. 

Does he/she want to join two plywood board edges at right angles to one another? Something else?


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