I don't know if it is a senior citizen thread. I have an HP41CX. RPN is great.

In the G-codes before the drill canned cycle, make sure there is a G98 instead of a G99. G99 will return to the R value between moves while the G98 will return to the initial height between moves.

Someone suggested a while back to use an unused machine offset. I have several Haas machines with different X travels so I use G110 and set that in my offset page. Therefore I don't need to make a specific post just to center the machine.

I use 508 rpm then all you have to do is multiply the pitch by 20 ex M6 x .75 508 rpm 15 ipm

Thanks again for all the help. I read about the problems that other have and the various solutions. It is alway great to add more solutions to one tool box. It was this forum that I read about using alum to erode HSS from aluminum and SST. We actually tried it and the tap was removed after about three weeks in cold water. Thanks again.

I hadn't gotten to the end of the flute, so I know that wasn't the problem. I have caught a chip between the material and the solid part of the shank before and it go exciting real quick. I will attempt to never let it happen again. Using the information that everyone kindly provided, I ran an experiment on the other hole location and it worked great. Thanks to everyone that has help. I have been lurking on the forum for several years now, and it has helped in many ways. Thanks again. PS I know not to ask for post processors.

I will slow everything down. I haven't machined much stainless, but I have heard that if I go to slow on my feed, I will work harden the material. At 534 rpm, with a 1/2" drill, I am at 70 sfm. From everything this thread is telling me, I am still way to fast. I will slow it down. I appear to be taking way to much per tooth. I will slow that down also. The smaller drill and ream is only what I can get fast. I only have 7 holes and only one of those is 6" the others are 4". The drill broke on one of the shorter hole, so I thought I better look for some advise. Thanks.

I am checking now with my tooling supplier now. With what he has available, I may go with a smaller drill and then ream the hole. I have to check the length of reamers I have in the shop. Thank you for all the information.

That is a good idea with the stub drill. I will give it a try. We do not have coolant thru. We use Blazer 2000 coolant. I will also check the concentration. Thanks.

Yes I am pecking with a full return to help evacuate the chips and allow the coolant to pool in the hole. I am going to try and use an old endmill to remove the drill pieces. Thanks.

I am trying to drill a 1/2" hole approximately 6" deep in 304 SS. The holes are for heating cartridges for a heat staking machine. We had a 1/2" dia. by 12" long 135 degree cobalt aircraft drill. It got to about 3 inches and stopped the spindle. 534 rpm @ 4.28 ipm. When I tried to remove the drill, it broke in the hole. Any help is appreciated.

Discovery or the Learning Channel had a show call "Machine Tools". It showed a lot of different types of machines in action.