I’m working on the 6-4 grade stuff.
I’m going to buy some tooling and I’m not sure what would be the best to get.
I have always center drilled my holes with a combination center drill, and then drilled with a regular HSS 118 degree drill.
I have heard that spot drilling is actually better for doing the same operation as a center drill. Can anybody elaborate on why that is the case?
So If I am going to be buying some spot drills, which angle should I buy? I notice they come in angles of 90, 120, and 140.
Also, assuming that I will then be drilling these holes, should I stick with a regular 118 degree drill or can I move to the smaller screw machine length drills that are shorter and seem more rigid? Most of these have a 135 degree angle, and I’m not sure if this would be good for Ti.
Most holes I’ll be drilling will be less than 5/16 in diameter, and through less than 1/4″ of material.
I know that solid carbide would be best for Ti, and coated as well. I will definitely go ahead with that with the spot drills I buy, but not sure about the drills.
I will also be reaming some holes through the same material, and I was advised by someone that carbide tipped reamers would be better than solid carbide, because I would retain the “semi-flexibility” of the HSS body, while still having the strength of the carbide cutting edges. Solid carbide for a reamer seems good but brittle, and that’s the reason this person suggested that.