Help with hole in thick stainless

[abarnett]

I'm building out a new keggle, and having trouble with the last hole. I want to install 1/2" plumbing through the chime, where the stainless looks to be twice as thick as the regular keg walls. I'm guessing it's around 1/8". I trashed a few speed bits drilling the hole for my punch. Then I broke the draw stud and bent a point on my Greenlee punch. I tried a cheap Harbor Freight punch, but it died instantly. My old step bit made a little progress, but now it's toast as well.

What is my next (economical) option? Will a 7/8" hole saw from big-box work? Do I go for another cheap step bit? Or will I have to spend the money on a more expensive step bit or a new Greenlee punch?

What do people use to get through thicker stainless?

 

[duboman]

I actually found it more affordable to take mine to my local welder/fabricator and him do it. The price was about the same as the bits and in his press he knocked it out in about 15 minutes

 

[jcaudill]

Hole saw - carbide or cobalt tip. Go very slow, lots of cutting oil and do it in a WELL ventilated area. It will go. I did a 7/8" hole this way in a 4" TC cap and that is probably over 1/8" thick. Expect the saw to be toast following.

 

[TrainSafe]

Greenlee makes special punches for stainless, but they are pricey. Look for SlugBuster series.

You can do it with a step bit, but go real slow and use lots of oil.

 

[jcaudill]

I'd not spend a lot money. Get cheap bits because you're very likely to ruin them.

 

[acidrain]

Cheap bit's (you've already learned) won't work.
I've not had good luck using a holesaw on stainless.
Cobalt is what we use to drill stainless, but a 7/8" cobalt drill is going to be way expansive.
Maybe start with a smaller hole and grind it to size with an abrasive stone on a high-speed (air) drill, or Dremel. it will take several grinding bits and some sweat (if you really want to do it yourself).

 

[gtmaus]

trick to cutting stainless is a lot of cutting oil and drill very slow. It'll go through. Once the bit heats up it's done.

 

[Mumbly]

I have very little to add that hasn't been said, although I was able to drill 8 holes with 2 cheap ass harbor freight step bits(both are still going fairly strong), and 6 of those were through double walled kegs. The key as said before, lots of lube, and take your time.

 

[abarnett]

Thanks, everybody!

I think the step bit will be more useful for other projects than a single-size hole saw, so I'm going to try again with some cutting oil (I'd been using WD-40) and a new step bit.

I'll also try to figure out how to get the keggle under my drill press and turn the rpms down. If I can't get it under there, I'll *just* have to upgrade my hand drill to a variable speed model.

I'll let you know how this goes...

 

[abarnett]

That sucked, but I eventually got the hole big enough. I got a cheap variable speed drill and another step bit (total cost $80). The heat coming off the drill motor burned my hand a bit, and I had to use a file to finish up. Luckily this doesn't have to be water tight.

 

[flanneltrees804]

I used a Milwaukee 3/4" hole saw and a corded, low rpm drill and a bit of cutting oil. Worked like a charm and I got 8 holes drilled in minutes and the bit is still in good shape...