I want to drill into my SS kettle - How do I make the hole threadable?

[cannman]

I'm going to drill into my kettle. I'd like to be able to directly screw in a 1/2" MPT Thermowell... I have a step bit that I use to drill holes into metal, but how do I drill it to accept the threads?

Thanks!

 

[troy2000]

I'm going to drill into my kettle. I'd like to be able to directly screw in a 1/2" MPT Thermowell... I have a step bit that I use to drill holes into metal, but how do I drill it to accept the threads?

Thanks!

You'd use a thread tap, which cuts the threads as you screw it into the hole. But I think most stainless steel pots are too thin to provide secure threads for a 1/2" or thereabouts fitting...

 

[Tokoroa_Brewer]

Measure the outside diameter of about halfway up the thread then subtract 2x the hight of the thread. That will give you the size of hole you will need.

 

[cannman]

You'd use a thread tap, which cuts the threads as you screw it into the hole. But I think most stainless steel pots are too thin to provide secure threads for a 1/2" or thereabouts fitting...

I did an amazon search for "Thread tap" and I think I found a tool that would work, just slap it into a drill and bore away... I hope it's that easy.

The SS pot I have already has a manufacturer-drilled threaded thermowell, I'm just looking to get a little fancy, so I'm fairly sure it will take. :rockin:

Measure the outside diameter of about halfway up the thread then subtract 2x the hight of the thread. That will give you the size of hole you will need.

 

[orangehero]

You use a tap in a tap holder and carefully cut the threads in. Look up youtube on how to do it properly.

I will echo the comment that the pot is too thin for threads for a thermowell. You can cut the threads and the fitting will thread in but it won't make a good seal. You either need a coupling welded or soldered in or a weldless assembly that can make a secure mechanical seal against a gasket. Do you have photos of the thermowell that's on your pot now?

 

[cannman]

You use a tap in a tap holder and carefully cut the threads in. Look up youtube on how to do it properly.

I will echo the comment that the pot is too thin for threads for a thermowell. You can cut the threads and the fitting will thread in but it won't make a good seal. You either need a coupling welded or soldered in or a weldless assembly that can make a secure mechanical seal against a gasket. Do you have photos of the thermowell that's on your pot now?

Photos yes. I'll post in 2hrs

 

[troy2000]

I'm not a machinist, but I think about the most threads per inch you'll see on a 1/2" tap is thirty two, and they'd be pretty shallow threads. I doubt your thermowell has that many threads per inch. So the odds of getting a tight and strong connection are pretty low because you'll have at most one or two full threads. And if you try to run the tap in with a drill, I can almost guarantee you'll just strip the hole out bigger instead of cutting threads.

 

[TedandMargeBrewing]

I'm gonna have to agree with the other posters. Your well probably has 1/2"-13 NPT threads. You are gonna want to install a 1/2"-13 locknut/o-ring and perhaps a washer as well to get a good seal. But, maybe you have a really thick sidewall and it will all work out great. A pic of your final product would be great!
May the 4th be with you!

 

[cannman]

Hey guys! Everybody who voted that the threads were for the gaskets and nuts... YOU WERE RIGHT. This misconception has allowed me to rethink the entire process and threading is no longer an issue. Thanks for your guidance!

 

[brew_ny]

I'm not a machinist,

but you stayed at a Holiday Inn Express?

 

[troy2000]

but you stayed at a Holiday Inn Express?

 

[burninator]

I'm not a machinist

Hey, man, what takes place between two consenting adults behind closed doors is none of my business.