Originally shared by Paweł Dobrowolski
I have made today one of these. Does anyone know what kind of endmill is used to make common mk7 drive gear?I used 4mm double flute end mill for stainless steel.
They use a hob with a 1mm lead
could you paste links to this hob?
Most people at DIY level are using taps. Typically m6 or 7. 7 works nicely because its stiff enough to decrease some of your tool deflection.
I am not at amateur level…
We use a knurling tool. Expensive but predictable. We used to use a tapping jig at a slight angle. That part looks choice!
A convex knurling tool would do the job. Might need to be a custom tool for the job though. I haven’t checked to see if someone currently makes one with the required specifications yet.
I can buy custom tool for this job but I have cnc with 4th axis and each teeth is cutted with endmill like in this my earlier video https://www.youtube.com/watch?v=ddsJ0jiFjCk
But in this method teeth is pointed in one direction like at the picture above.
Well, a side cutter with a V profile might do the trick. If you can find one with the appropriate dimensions. The radius would have to be pretty small. Given that you have a cnc mill you might be able to make one if you have a grinder attachment and some HSS.
I cleaned up my hobbed bolt with a Hart burr and it worked great.
I don’t even know what a hart gear is!
The knurling is fast and spits out consistent parts every time. It is a $400 custom knurling tool, btw.
@Brook_Drumm knurling is much faster that cutting each teeth. Are all jobs made at lathe?
Yes, a big one with auto stock feed.
@Brook_Drumm A Hart burr is a cutting tool with a diamond shaped head used by jewelers primarily in a rotary hand piece. Burrs are usually much cheaper than exotic shaped milling cutters so, while not suited to mass production, may sometimes be a good choice for hobbyists, especially those that can manage indexable milling (Sherline or similar).
Cool! Leave it to a watchmaker to school us all on rare and exotic tools. Maybe I need to hire a watchmaker 
I bet I’d get some cool tool knowledge out if the deal!
Brook
I have found that deburring/chamffering endmill with 45 degree angle can make the job easily.