# what size dowels to use



## sweets (Apr 13, 2009)

I'm getting ready to begin construction of a kids table and chair set made of oak. I plan to use dowels and glue for all of the joints. Which size, type (spiral?), and species dowel should I use? The table top, rails and seat tops will be 3/4 thick; the chair legs/back approx 15/16 thick, and the table legs approx 1-5/8 to 
1-3/4 thick.


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## CharlieM1958 (Nov 7, 2006)

I use dowel joints quite often, and I find 3/8 is a good size to use when working with stock in the 3/4 to 1" thickness range. I normally use 2 dowels at each joint. Be sure to get dowels made for gluing that have flutes of some sort to allow excess glue to squeeze out. Otherwise, the hydraulic pressure of the glue in the hole makes it almost impossible to close the joint.


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## FirehouseWoodworking (Jun 9, 2009)

The rule of thumb that I learned was to try to use dowels whose diameter is half the thickness of the material being joined.

As Charlie has already indicated, ALWAYS use dowels which are spiral- or straight fluted to allow for glue squeeze out. And I agree that at least two dowels should be used per joint. If you're joining wide boards, use more.

Another important thing to do is to drill each hole about an 1/8" deeper than you drive in the dowel. In other words, if the dowel is 1" long, you'll drive it 1/2" into each piece to be joined. Drill each hole 5/8" deep. This creates a little "pocket" at the end of the dowel that allows for the glue squeeze out.

All these steps will greatly lessen the chance of splitting the piece of lumber.


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## a1Jim (Aug 9, 2008)

Hey sweets
You brought up the table top. It is a bad idea to connect the top with dowels because of the expansion and contraction of the top due to moisture , you need to connect the top with connectors like fiqure 8s . Dowels are not my first choice for joinery because they are one of the weaker types of joinery, but they are used frequently by many people.


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## sweets (Apr 13, 2009)

Jim,

Can you describe the figure 8 connectors? Would just gluing the table top be better than using the dowels?


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## CharlieM1958 (Nov 7, 2006)

Lee, are you talking about attaching to top to the apron, or the actual gluing up of the top from smaller boards?

It is okay to use dowels to glue up the top (although not really necessary). Jim is talking about how you connect the top to the legs/apron assembly. He was referring to these, I think:

http://www.leevalley.com/hardware/page.aspx?c=2&p=50311&cat=3,41306,41312


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## a1Jim (Aug 9, 2008)

Hi Again Lee
In case I didn't make my self clear in the PM Charlie has it correct. glue the boards to the top together but not to the apron. BTW I think the type of figure 8s Charlie sent is a stronger one then the link I sent you.


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## patron (Apr 2, 2009)

for top to apron ,
at charlies , lee valley site ,
table top mounting clamps , #13k01.01
they even have a picture of them in use .


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## CharlieM1958 (Nov 7, 2006)

Actually, the ones David is talking about are what I use all the time.


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## sweets (Apr 13, 2009)

Guys,

I meant using dowels to join the taple top to itself, not the apron or legs. I plan to attach the apron to the legs on both the table and the chairs using dowels. From what I've been reading on this site, I figured I would need to use the table top mounting clamps which David and Charlie suggested. I was going to ask that question when I got closer to that step. So ya'll answered it for me already.

Speaking of the clamps, it appears as though I would need to create a channel (rabbet?) in the apron with either the table saw or router. Is that correct? How far apart should I put them, and do I use them on all four sides? Use on the chair seat to apron as well? Table top will be 30 in x 30 in and seat 13 in x 13 in.


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## CharlieM1958 (Nov 7, 2006)

Just use the clips on the 2 sides that run in the same direction as the grain of the table top. For a table that size, 2 clips on each side should be fine.

You can cut the channel in whatever way is easiest for you. I like to use my biscuit joiner, so instead of cutting a channel the whole length of the apron, I just cut one biscuit slot wherever a mounting clip is going to go. The width of a biscuit slot still leaves plenty of room for wood movement.


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