Not long ago, I purchased a A.C. BARTLETT'S OHIO PLANES #120 handled screw-arm plow plane on ebay. It did not come with a wedge or irons so I went down to see Ed who occupys the 2nd floor over The Woodwright School in Pittsboro. Ed found a wedge and 6 irons that would work. My problem is not knowing how to set it up. I sharpened the iron to 35 degrees for extra strength (it is quite sharp). I have it bevel down and inserted the wedge. I have the iron only 1/4" below the skate (the vertical metal plate that touches the wood) but the iron keeps catching in the wood and I am not able to push it. I know that I am doing something wrong. I tap the wedge in with a wooden mallet but sometimes it comes loose when I try to push the plane very hard.. Suggestions would be very much appreciated. If pictures are needed, I can supply them.