The plow plane, while primarily cutting grooves, is a versatile plane for many groove and rebate operations. Lets start with the basics.
Using the plow is a bit unlike using a bench plane that you are probably more familiar with. First off it has a fence and a depth stop. Second of all the goal is to make a shape, in this case a groove, as opposed to flatten a board.
With these difference come a difference in technique in using the plane.
Set up the Tool
Set the depth stop for the depth you want your groove to be. Insert an iron for the width of the groove you want to create and set the iron for a thick cut, no whispy shavings here. We need to get this groove cut quickly. Then set the fence to position your groove at the proper distance from the edge of the board.
Holding the Tool
Grasp the plane tote with your dominant hand like any other plane. Your off hand will be used to apply pressure to the fence onto the work. Your dominant hand will push the plane forward but resist the urge to guide the plane while pushing. Allow your off hand and the fence to guide the plane.
Starting the Cut
Here's where things really start to differ. You start at the far end of the board and work back toward the traditional beginning portion of the cut in increments. I like to start about 6 inches from the end of the board and take two cuts and then move back six inches and cut again all the way to the end. Repeat until you reach the start of the board. This establishes the groove while minimizing the tendency of the plane to follow the grain of the board in a long cut. This technique is also useful for complex moulding planes and some rebate planes. Continue taking full length cuts until the plane hits the depth stop and no longer cuts. Congrats, you have a groove.
Making a Rebate
While it may be more convenient to make various small rebate with the plow plane you can also make some very large ones.
First, counter-intuitively, place the narrowest iron you have in the plane. The object here to to remove a lot of waste without doing a lot of work.
Set fence so the plane cuts a groove just inside the waste area of your rebate from the scribe line. Set the depth stop so that the plane will cut to the depth of your rebate. Cut that first groove. Then turn the work 90 degrees and set the fence and depth stop similarly from the other scribe line. Cut the second groove. You'll cut a little stick of waste free when you hit the other groove and, tada, you have a rebate.
A few tips on the Veritas Small Plow Plane
I've learned a couple of things about my Veritas plow plane I thought I'd share with you.
Adding a thin auxiliary fence to the plow can help it register more positively on the work, Veritas has already provided some countersunk holes on the fence to help you out.
The longer fence rods for the Veritas Skew Rabbet Plane also fit the plow plane, allowing you to make grooved further from the edge of the board than the stock set of rods will allow. I've found this handy, don't know about you.
I hope you'll give a plow plane a try and would appreciate any input on plow techniques that anyone is using but I may not have thought of.