What problems can occur when dowelling?
Dowelling can be a tricky process as it requires accuracy at all times.
It's easy to make mistakes but don't be put off! Being aware of potential problems can help you to avoid running into them during your dowelling project.
Uneven drill holes
If you find that the holes you're drilling are not perfectly round then it's likely that your drill bit is not straight.
Once a drill bit becomes bent, it will need to be replaced as it can no longer drill holes accurately.
If you find that your joint does not connect properly, or that the two pieces of wood you are joining are not lined up properly, there may be a problem with the way your holes have been drilled.
If dowel holes are not drilled at 90 degrees to the wood's surface, the pieces of wood you are joining will not meet up properly and you will be able to see your dowel pegs in the resulting gap.
If this is the case, then you need to disassemble your joint, check which piece of wood has been incorrectly drilled and replace it with a new piece of wood with correctly drilled holes.
You may need to start the joint again from scratch.
If the edges of your joint are not in line, it's likely that your dowel holes were drilled incorrectly in your second piece of wood.
Fixing this is a little easier. You can do it by disassembling your joint and re-drilling your holes in the correct place.
For more guidance, see.
Making a dowelling joint can sometimes cause wood to crack. This is usually because of something called hydraulic pressure.
Hydraulic pressure is caused when something pushes down on liquid that is already in a confined space. The pressure that is being put on the liquid is then transferred to the material that contains it.
The added pressure on that material can cause it to break along any weak points. For example, wood would break along the grain.
This can be avoided by using fluted or grooved dowels, or by cutting nicks into plain dowels to allow the glue to escape the joint.
It can also be avoided by drilling a hole 1mm wider than the dowel you are intending to use.