Step 6Making a Dowel Joint
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Dowels can be used to connect two boards side to side together to create wider shelves or chair seats (Pic 20)or workbench counter tops. 1/2" to 3/4" dowels connect the boards together and are held in place by 1/4" lock dowels. Since dowels are usually pretty dry and wood is somewhat wet they tend to swell up and stay in place without glue. So you can consider this a permanent joint that will not come apart easily. You will usually have to drill out the lock dowels to get it apart.
Pic 21-I usually leave a 1/8" to 1/2" crud gap between the two boards to allow dust and junk to fall through. If you try and make the joint totally tight, it tends to gunk up.