Notching 4130 tubing

[z28kla]

Hi all. Newbie here with some questions. I tried a search but came up with nothing. Maybe i'm just doing it wrong... Any how, I had a few questions about how to notch some tubing on my new mill. I have been using a tubing notcher but hope to save some time by having the mill cut it. What I am cutting is 1"X.065 wall 4130 tubing. The tube is offset notched on both sides. One side is notched at 1.5" the other side is 3.5" both are notched so the 1" tube is sitting on top of the others. I hope that makes sense. These tubes are going to be Tig welded together so a super fine finish is not all that important.
My questions are:
What kind of end mill material should be used? HSS Cobalt or Carbide?
Should I use use a finishing bit, roughing bit, or roughing-finish bit?
When cutting should I start from the bottom of the tube or the end?
Coolant or not?
Coated end mills?
3,4 or 6 flutes?
I have more questions but will have to post pics in order to better explain.

I hope these questions are not ridiculous, I just don't want to buy end mills I wont need.
Any help would be appreciated.
Lance

[MrWild]

What mill do you have? A small X2 doesn't like 1" endmills.

[z28kla]

Just purchased a CNC Supra from CNC Masters.
1" end mill? I was thinking about using a 1/2" end mill...
Lance

[ctate2000]

Use IMCO Powerfeed end mills. They are wicked tough we use them on 4140 forgings that have been heat treated to 40HRC. 1/2 dia will be about
$30. They are coated and perform well with or without coolant.

[z28kla]

Originally Posted by ctate2000 Use IMCO Powerfeed end mills. They are wicked tough we use them on 4140 forgings that have been heat treated to 40HRC. 1/2 dia will be about $30. They are coated and perform well with or without coolant.

Thanks, I found their website. Looks like good stuff. I bought some jobber cobalt end mills from Enco today. At $10-$20 a piece I figured I just give them a whirl. I got two rougher-finishers and two standard center-cutting 1/2" end-mills. I also purchased v-blocks that clamp to the table and also have independent workpiece clamps to hold the tubing. I will post some pictures of each one of the end mill finishes. I'm still am unsure about which side of the tube to start from??? I was reading about the difference between conventional milling vs. climb milling and don't really understand which is applicable here since both notches will be an internal contour. I guess I'll give it a shot both ways and see which works best. Worst case scenario I break or chip a bit...
Also the internal contour on one side will be opposite the internal contour on the other side. I'll post pics as soon as possible.

I plan to use this site a ton in the future. I feel best when I can give as well as take. I appreciate any and all help given and hope that through my "stupid" questions many more will not have to ask them.
Lance