tapping 10/24 in stainless

[Joels]

Hello,

I am currently trying to drill and tap 316 stainless steel. I am starting with a center drill then followed with a #25 drill. we break some of these but the problem is the tapping. we drill to a depth of .800 and we are trying to tap to a depth of .500 but after 4 holes we break the tap. we have tried different rpms and it doesnt get better. I am using a fadal VMC. Anybody have any suggestions for tapping?

[kccadcam]

Look here:

 

http://www.emastercam.com/ubb/ultimatebb.p...c;f=11;t=000985

 

Use the search function, tons of topics on tapping.

[Joels]

i saw that thread but i dont know what the difference is between 304 and 316 for machining

[Surface]

Is this a continuation of this? You got some good advice there. Use a decent brand drill, screw machine length, split point, 80 SFM, .0015 FPT. No centerdrill. Roll tap. Molly-dee. No problems

[Kevangel]

drilling and tapping fluid from "Union Butterfield" Ashevill, NC 28813 "clear and thick" ,it really makes a difference in stainless. very cheap for big 16oz. bottle. Best tapping stuff I have ever seen. I have tried a bunch...bottle says non toxic..

[Harryman]

Form tap.

 

If you cannot form tap (stupid boss forbids it or something) drill on the large side of the chart and peck tap.

 

If your drill is "wearing" that high speed steel is getting stuck to the walls of the hole and can cause huge problems tapping.

 

Coolant fed carbide drills are the best.