Help tapping stainless steel - Home Brew Forums
Register Now For Free!

Home Brew Forums > Home Brewing Beer > DIY Projects > Kettles, Mash Tuns & Hot Liquor Tanks > Help tapping stainless steel

Reply
 
Thread Tools
Old 11-07-2009, 06:01 AM   #1
jppostKW
 
jppostKW's Avatar
Recipes 
 
Jan 2009
Englewood CO
Posts: 1,807
Liked 11 Times on 11 Posts



I built a diy version of derrins sanke conversion today all went well until I tried tapping the holes one was drilled to 7/16 for a 1/4 npt fitting the other 9/16 for a 3/8 npt I used thread cutting oil but it was really tough and ended up chipping my 3/8 npt tap the cap is 316L I was wondering if I need to use a specific stainless tap are my hole sizes wrong etc.

Thanks guys
Paul
__________________
Diesel Fuel Brewery

Quote:
Originally Posted by paulthenurse View Post
It would be the brewing equivalent of painting the Sistine Chapel with Crayola Crayons.
Quote:
Originally Posted by Stuntman View Post
You sir, are a specialist in the art of discovering a welcoming outcome of a particular situation....not a mechanic.

 
Reply With Quote
Old 11-07-2009, 11:05 AM   #2
marzsit
Recipes 
 
Sep 2009
kent, wa.
Posts: 316
Liked 6 Times on 6 Posts


sounds like the heat generated during the hole drilling has work-hardened the stainless.. unfortunately i don't know of an easy way to anneal stainless once it has turned into glass.

 
Reply With Quote
Old 11-07-2009, 04:45 PM   #3
Dwain
 
Dwain's Avatar
Recipes 
 
Feb 2009
Hill Country, TX
Posts: 1,135
Liked 5 Times on 5 Posts


Do yourself a favor. Call some local machine shops and see what they will charge to do it or if they can recommend someone. You will destroy the taps that you can buy from Harbor Freight, Lowe's, and Home Depot. Then you're about $60.00 in, at least, and whistling "who da thought it". I'm sure everyone else on here, besides you & I, has been successful doing this. Maybe you can even coax them with some homebrew. The guy I used drinks Miller Lite, so it was even cheeper. Let me know what you do. Luck - Dwain

 
Reply With Quote
Old 11-07-2009, 06:18 PM   #4
kladue
Senior Member
HBT_LIFETIMESUPPORTER.png
Recipes 
 
Dec 2006
Turner, Oregon, Oregon most of the time now
Posts: 2,305
Liked 53 Times on 47 Posts


The hole sizes sound correct, here is a chart http://www.engineersedge.com/manufac...rill-chart.htm. The most succesful method I have used for tapping stainless steel is to advance 1/4 turn then back up 1/2 turn to break the chip, then advance another 1/4 turn past previous ending point. If you try to go forward continously like you can with carbon steel the chips will sometimes bind and shatter the tap face. It is best to start with a new tap and pitch it in the junk pile after a couple holes as the stainless is really hard on non cobalt alloy taps.

 
Reply With Quote
Old 11-07-2009, 06:29 PM   #5
jppostKW
 
jppostKW's Avatar
Recipes 
 
Jan 2009
Englewood CO
Posts: 1,807
Liked 11 Times on 11 Posts


The taps are snap on not cheap and kladue that's the basic method I used.
Dwain this was basically seeing if I could build something cheaper than buying.
20 bucks shipped for tri clover clamp cap and gasket
12 for the SS racking cane
I already had the compression fitting and barb fitting but they would add two bucks apiece
That's a total of 36 dollars I guess if a machine shop cuts and taps the holes I have to bank on the guys working for beer!
Thanks for the insight so far.
__________________
Diesel Fuel Brewery

Quote:
Originally Posted by paulthenurse View Post
It would be the brewing equivalent of painting the Sistine Chapel with Crayola Crayons.
Quote:
Originally Posted by Stuntman View Post
You sir, are a specialist in the art of discovering a welcoming outcome of a particular situation....not a mechanic.


 
Reply With Quote
Old 11-07-2009, 07:25 PM   #6
Dwain
 
Dwain's Avatar
Recipes 
 
Feb 2009
Hill Country, TX
Posts: 1,135
Liked 5 Times on 5 Posts


Yeah, I used an old Mac tap first and ruined it, then the succession of others. Most machine shops routinely cut and thread stainless. That stuff is harder than Superman's knee caps. Luck - Dwain

 
Reply With Quote
Old 11-07-2009, 10:28 PM   #7
kladue
Senior Member
HBT_LIFETIMESUPPORTER.png
Recipes 
 
Dec 2006
Turner, Oregon, Oregon most of the time now
Posts: 2,305
Liked 53 Times on 47 Posts


I have nothing against Snap On but these Cobalt steel taps will deal with the harder stainless http://www.grainger.com/Grainger/wwg...PT&N=0&sst=All. The other thing that will help is up sizing the drill size for the connection and using a bit more tape on the threads.

 
Reply With Quote
Old 11-08-2009, 02:45 AM   #8
sudbuster
This ain't my first rodeo....
HBT_LIFETIMESUPPORTER.png
 
sudbuster's Avatar
Recipes 
 
Jul 2007
Western Arkansas
Posts: 4,030
Liked 283 Times on 219 Posts


Quote:
Originally Posted by jppostKW View Post
I built a diy version of derrins sanke conversion today all went well until I tried tapping the holes one was drilled to 7/16 for a 1/4 npt fitting the other 9/16 for a 3/8 npt I used thread cutting oil but it was really tough and ended up chipping my 3/8 npt tap the cap is 316L I was wondering if I need to use a specific stainless tap are my hole sizes wrong etc.

Thanks guys
Paul
you will find some tough going in stainless without using an npt reamer...

 
Reply With Quote
Old 11-08-2009, 03:24 AM   #9
jppostKW
 
jppostKW's Avatar
Recipes 
 
Jan 2009
Englewood CO
Posts: 1,807
Liked 11 Times on 11 Posts


Quote:
Originally Posted by Sudbuster View Post
you will find some tough going in stainless without using an npt reamer...
This guy right here is a thinker!!!!!!!!!!!

Might have to look into this
__________________
Diesel Fuel Brewery

Quote:
Originally Posted by paulthenurse View Post
It would be the brewing equivalent of painting the Sistine Chapel with Crayola Crayons.
Quote:
Originally Posted by Stuntman View Post
You sir, are a specialist in the art of discovering a welcoming outcome of a particular situation....not a mechanic.


 
Reply With Quote
Reply
Thread Tools


Similar Threads
Thread Thread Starter Forum Replies Last Post
Stainless steel question baer19d Kettles, Mash Tuns & Hot Liquor Tanks 22 06-16-2011 05:05 AM
is there any way to tell if something is Stainless Steel Grinder12000 Equipment/Sanitation 25 05-12-2010 01:44 PM
Suggestions for a stainless steel pot Q2XL General Beer Discussion 18 12-01-2009 04:45 AM
Stainless Steel v. Aluminum DirtyJersey Beginners Beer Brewing Forum 18 03-23-2009 08:37 PM
Stainless Steel Burners HenryHill Equipment/Sanitation 8 03-20-2007 09:38 PM


Forum Jump