Many of you are probably already using dogs but for those new to milling may find this of interest.
These are the simplest of items to make and one of the most useful pieces of kit to have to hand for setting up the mill.
They are simply hexagon or square pieces of material cut to the desired length that are a good tight fit in the tee slots of the machine table. They can be drilled so they can be permanently fitted to work holding devices, this is why I prefer hexagon as it can be held in a three-jaw chuck to be drilled centrally.
Sometimes vices etc. have a pre-machined slot and tapped holes so your own dogs can be fitted.
Please note I have stated hexagon or square stock. I do not recommend round stock as the point contact of round stock can damage the tee slot when pieces are pushed against them.
I use machine dogs for alignment of all types of items on the mill from angle plates, Vee blocks, vices, dividing head, jigs and fixtures or just the workpiece being machined. As previously stated dogs can be permanently attached to the base of certain items such as the machine vice and dividing head but others items are simply pushed against the dogs for alignment.
Please see the photos below showing vee blocks being pushed against the hexagon dogs and photos show permanently fitted dogs to vices and an indexing head.
5/8" hexagon to suit tee slots on Bridgeport mill.
Two vee blocks alingned by pushing against the hexagon tee slot dogs.
Vee blocks and dogs moved further apart to support longer work piece.
Permanently fitted dogs
Thank you for viewing
The Home Engineer