Need Buttress thread info

[mike561h]

Hey Friends,

 

Any ideas on where I could find specs/gauges/tooling etc for a saw tooth buttress (3 deg / 30 deg) thread? It is also called the “filettatura a dente di sega” in Italy and the “Sagengewinde” in Germany. They have specs (which I can’t read) but I haven’t been able to find an ansi or similar spec. Any ideas?

[TheePres]

filettatura a dente di sega, tranlates to "cut it with a hacksaw"

[CNC USA]

Hello,

 

Here is the info needed on your Buttress Thread. Not sure on were to get tooling.

 

 

Metric Units

 

 

 

S12 x 2-7e external specs

 

Allowance,0.071

 

Major Diameter Max,12.000

 

Major Diameter Min,11.957

 

Pitch Diameter Max,10.429

 

Pitch Diameter Min,10.229

 

Minor Diameter Max,8.529

 

Minor Diameter Min (Ref),8.208

 

Crest Radius (Ref),--

 

Root Radius (Ref),0.249

 

Flat At Root,--

 

Thread Height (Basic),1.736

 

 

 

S12 x 2-7H internal specs

 

Allowance,--

 

Minor Diameter Min,9.000

 

Minor Diameter Max,9.236

 

Pitch Diameter Min,10.949

 

Pitch Diameter Max,11.214

 

Major Diameter Min,12.000

 

Major Diameter Max (Ref),12.070

 

Flat At Root,--

 

Thread Height (Basic),1.500

 

 

 

Pitch,2.000

 

Lead,2.000

 

Starts,1

 

Lead Angle,3.493

 

 

 

Included Angle,3 x 30

 

Good luck

[steveo25]

We use butress threads regularly at my shop. Valenite makes a butress snap tap threading insert that works good. Unfortunely our engineers figure all the the O.D. thread over wire information out but it shouldn't be to hard to figure out using mastercam.