[benamcg]

I will be drilling through my SS kettle to attach a weldless valve kit so that I can begin to use my Therminator. 

I have all the equipment ready to go, including my titanium nitride step bit, but am trying to solicit advice from someone who has done this before proceeding.  I keep putting off the operation thinking that I am about to wreck a perfectly good kettle.

I have a 18 V cordless drill, but what speeds should I run it at?

Did the finished hole require smoothing?  If so, with what?

What did you use for cutting fluid?  I dont want to have greases in the kettle or anything that could be problematic.  I am not looking to use the bit again if that matters (i.e. if I dont need to use cutting fluid?).

Thanks

Ben

[jamminbrew]

 A regular metal drill bit should be fine.  If you're worried about it, use a soaking wet sponge above the bit, keeping it in slight contact.  That should keep it cool. Speed would be a med-low speed, but probably won't matter.  Once you're though, use a fine rat-tail file to remove any burrs and smooth the cut down.

[davidw]

The step-bit/unibit is the way to go. It will cut a nice, smooth hole. Start with a 1/8" bit and just drill a small pilot "divot" so the step-bit doesn't wander on the surface of the kettle when you start to drill. Use plenty 3 in 1 oil and drill with low speed and pressure, if you go to fast the SS will heat up it will get harder to drill. Clean up the oil with oxyclean and a blue scrubbie. I have installed weldless fittings on a dozen or more kettles/fermenters/kegs for myself and friends and this method has always worked well.

[alikocho]

The step-bit/unibit is the way to go. It will cut a nice, smooth hole. Start with a 1/8" bit and just drill a small pilot "divot" so the step-bit doesn't wander on the surface of the kettle when you start to drill. Use plenty 3 in 1 oil and drill with low speed and pressure, if you go to fast the SS will heat up it will get harder to drill. Clean up the oil with oxyclean and a blue scrubbie. I have installed weldless fittings on a dozen or more kettles/fermenters/kegs for myself and friends and this method has always worked well.

I'm curious as to why a step bit is the way to go. Would a hole saw work as well?

[euge]

My experience is that the step-bit is more precise and a good one cuts through steel easily. Also leaves a cleaner hole with few burrs.

[benamcg]

Start with a 1/8" bit and just drill a small pilot "divot" so the step-bit doesn't wander on the surface of the kettle when you start to drill

Some people have recommended tapping a punch into the kettle to make the divot.  But you are saying I could do this with the bit?  I am worried about the punch ended up damaging or denting a larger area than the intended hole.

[tygo]

I have a 18 V cordless drill, but what speeds should I run it at?

When I did this I had problems using my 18V cordless.  I could get up to about a 7/16 hole before it would freeze up.  However, several others have reported no issues with an 18V cordless.  My kettle is on the heavy side so that may have been the issue.

I eventually used a borrowed corded drill to finish it up.

[tygo]

Start with a 1/8" bit and just drill a small pilot "divot" so the step-bit doesn't wander on the surface of the kettle when you start to drill

Some people have recommended tapping a punch into the kettle to make the divot.  But you are saying I could do this with the bit?  I am worried about the punch ended up damaging or denting a larger area than the intended hole.

I drilled a pilot hole with a smaller bit to get it started.

[benamcg]

I have a 18 V cordless drill, but what speeds should I run it at?

When I did this I had problems using my 18V cordless.  I could get up to about a 7/16 hole before it would freeze up.  However, several others have reported no issues with an 18V cordless.  My kettle is on the heavy side so that may have been the issue.

I eventually used a borrowed corded drill to finish it up.

I have similar issues with my grain mill- I usually end up repeatedly switching out batteries. 

I should have specified that my kettle is the 60 qt Bayou Classic.

[Kit B]

Grab a can of WD-40, or some other adequate lubricant & give it a little spray.
tap the kettle lightly with a punch, just to make a tiny spot for your drill bit to grab.
Drill a very small pilot hole...I think I used a 3/32 bit.
Spray again & start your step bit.
Use light, but constant pressure & pause once in a while to spray.
Let the bit do the work...Don't go too fast or too hard.
To clean it up, I use a fine rat-tail file & emery cloth.
Then, I wash with Dawn, to remove all grease & debris.

I was terrified to drill my first one, but I've now done 4 & am very comfortable with the process.

[dak0415]

Ok, I've done 2 bayou classic kettles and a number of kegs.  The BC kettles are kind of thin so I started with a 1/8" bit to start the hole then went to 1/4" before I used the step bit.  I put the hole underneath the handles (Think about that as you are carrying a full, hot pot, "Where's the valve?").  BCs have a weld line up one side, it was also under the handle so drill on the other side so you don't try to put the hole through the weld.  With steel that thin, you don't need too much pressure, but DO put your drill on the slowest setting.

+1 on the WD-40, spray the step bit liberally so the oil will run down the bit to where you are cutting, don't spray the pot (lay the pot securely on it's side, best also to have someone holding it too) and re-spray whenever you increase a step.  Stop at 3/4" and see if the valve/nipple fits, then little by little until the nipple JUST goes through.  You can then use the step bit from the inside, VERY lightly, from the inside to deburr the hole.

Dawn IS the best for removing the cutting oil.

[narvin]

I didn't need to do any smoothing after drilling with a step bit.  My step bit was also self starting, so I didn't have to punch or pre-drill.

It's easiest to use garden hose water to lubricate during drilling, IMO.  It keeps the steel from heating up and cleans debris at the same time, and you don't have to worry about washing oil off of your kettle at the end.

Don't press too hard.  Let the tool do the work.

[benamcg]

Update: Success!

Thanks to one and all in this amazing community.  Much appreciated.

I ended up just placing the kettle in the tub, running water occasionally, going slow- the kettle, the hole, the bit and the drill all came through well.  Thanks for the tip on placing the valve under one handle (looks slick).  The bit (cheapo/ebay titanium nitride- $11.95) looks like it could go again.  Also, no rough edges on the hole.  The weldless kit is also holding strong- no leaks!

Thanks again
Ben

[Kit B]

Awesome!
Enjoy!!!