Started programming the grip today!
Hope everyone is doing well. Things are moving along. I just finished programming the Internal Diameter (ID) operations on the grip today. The new drills I got are from a different manufacturer. They have odd size shanks so I had to have a few more collets shipped from the east coast, so that and the 4th of July holiday set me back a couple of days. Enough chit chat, photos!
(Above) It doesn't look like much but that aluminum cylinder will eventually turn into a grip like the two prototype parts just above. The good news is that my custom taps actually fit the threads on the Montblanc cartridge...one of those things you can't really know until you test fit. Whew! Don't have to worry about that at least.
(Above) The ID operations are done, but I still have to program the Outside Diameter (OD) operations. I'll have to spend some time tweaking the exact shape of the tip. Again, it might look fine of paper, but you don't know if it looks or feels "right" until you transfer it to metal. All of the prototypes were machined on my Hardinge HLV manual lathe, and the shape of the tip was finished with a file and a cardboard pattern :)
I do all of my programming by hand, no help from software like CAM (Computer Aided Machining) programs that automatically write the code that controls the tool path. This takes a little bit longer, but I program by hand because I don't own CAM software and I enjoy the mental exercise of the "hands on" approach. Many new machinists have no idea how to hand write code even though they run CNC machines.
(Above) Once the OD and ID ops for the grip are set, I'll run a test batch of aluminum parts, and then send those off for plating. In the photo above, the (test batch) is for the pen body. The other two stacks of parts will go out for plating as a lot.
It's important to run a test batch because the plating process adds a significant amount of thickness to the parts. There is a risk that this buildup will mean the components won't thread together. You can measure and calculate all you want, but there is no substitute for confirming the fit in real life. After verifying the fit I can proceed with the rest of the aluminum parts. One nice thing about the Ti is that it's not plated. So, if the part fit when the come of the machine...then they fit...it's a done deal.
(Above) Sorry for the terrible phone video! All of the parts are tumbled in a vibratory bowl after machining. The aluminum parts (in the video) are processed with a "medium" cutting plastic media for 3 hours. This knocks of any sharp edges and also creates a uniform and very smooth surface. After plating, they will be nice and shiny!
(Above) After tumbling, the parts go into a tub filled with hot clean water and let soak for about 10 minutes. The hot water helps lift the metal residue off of the parts. Tumbling is a "wet" process where water and a surfactant are cycled through to wash away the microscopic dust that is generated. Even though the water is filtered and recirculated, residue remains and can make the parts "cloudy" looking. The hot water heats the metal and makes the water evaporate faster when removed from the tank. I learned that little trick making flashlights :)
(Above) As each part comes out of the wash tank, it is dryed with a microfiber cloth and is blown off with compressed air. It's hard to get "all" of the water out from inside the hole, so this is where the hot metal helps to speed evaporation and drying of the parts.
(Above) This is 150 finished aluminum caps. They are plated and have the pocket clip and brass screw installed. These parts are "done done" and that's pretty exciting! The only thing left is to mate them up with the body and grip and get them in the mail! Of course I still need to make all of the grips :)
That's all for now!
Cheers and thanks again for your patience and support!