I began this project by buying a 3/8 inch dovetail cutter with a 45 degree cutting angle. This cutter would normally be locked in a milling machine, but I am using a floor-standing drill press with a 3/4 inch chuck and the speed set quite low to prevent overheating the tool.
Figure 1 is a close-up photo of the dovetail cutter laying on its side. This photo was taken after the cut was complete and I had cleaned the lube and shavings off with mineral sprits. This cutter looks like it can handle many more cuts and does not appear to be damaged or dulled by the cut.
The next important item is a cross-sliding vise that simulates the moving table found on a milling machine.
The cross-sliding vise illustrated in Figure 2 allows the barrel to be clamped in the vise and then the vise is moved on the x and y axis to smoothly pass the part through the cutting tool.
The vise must be securely clamped or bolted to the table of the drill press so it cannot move while the cut is being made.
I clamped the octagonal barrel section into the vise and securely clamped the cross sliding vise to the table of the drill press. I locked the dovetail cutter into the chuck of the drill press as deeply as reasonably possible and tightly secured the chuck.
As part of the setup procedures, I removed as much play as possible from the drill press by tightening the locking collar that controls the vertical movement of the drill press.
With everything locked down as much as I could, I adjusted the base of the drill press to give me the desired depth of the cut. I cut this dovetail a little deeper than normal in order to provide a better photo.
Figure 3 shows the cutter in the vise and the barrel aligned just prior to starting the cut. After double-checking the alignment, I double-checked to assure myself that every movement was locked down to reduce play in the cutter and to improve the quality of the cut.
I checked the vertical column lock, the plunge stop, the clamping of the cross sliding vise, and even locked the vise components that did not need to move. With everything secure, I coated the tool and barrel with cutting oil and turned on the drill press.
It is important to feed the work into the tool very slowly to prevent chattering or tool deflection. Milling machines are more rigid than drill presses so the drill press cannot handle the the side loads as smoothly and a slow and patient feed is essential.
I slowly fed the material through the tool while adding cutting oil to allow cooling and to help float the chips out of the area of the cut. The cut took about five minutes and seemed to go well.
Figure 4 shows the cutting in progress as the tool is breaking out through the the near side of the barrel. The strobe of the camera actually stops the action, but the tool is turning and the flow of chips and cutting oil can be seen coming out of the cut region.
I continued to slowly move the cross sliding vise knob to bring the cutter clear of the barrel before turning off the drill press and removing the barrel. I could see a good cut covered with small chips and cutting oil.
Figure 5 shows the finished cut after being cleaned with mineral spirits. The cut is very clean and all angles appear to be perfect. The camera optics make the cut look a little uneven, but the cut is very nice.
This exercise shows it is possible to use a drill press along with milling cutters to produce high-quality cuts in the garage of the hobby gunsmith who is equipped with a good drill press.
Next I will make the new front sight to fit into the dovetail. Mohave Gambler
Don't throw away old tools, they can be reformed to make special-purpose tools.