Tapping / Helicoil Tapping

[Tinyfxds]

I have a bunch a holes in my part that need to be drilled and tapped for their respective Helicoils.  6-32, 8-32, 10-32 and 1/4-20.  If I'm correct the Helicoil taps have the same pitch as the threads you are trying to helicoil right?  So when I enter my pitch of .03125 (6-32, 8-32, 10-32) into Mastercam everything should be fine using a helicoil tap correct?

[Guest]

Yup, the difference is the tap drill and tap are slightly larger but the pitch is the same

 

 

DO note that if you ever get into locking inserts, they are typically a different outside size but Heli-coils are as you stated

[Tinyfxds]

There is a call out on the print that the 10-32 and 1/4-20 need to be locking inserts

[Guest]

Check the style they are calling out......

 

Some styles have a different outside thread, if it's just Heli-coil, then it's just a locking Heli-coil insert......

 

Keen-serts and others are a different ballgame

 

This style is a different beast

 

http://www.alcoa.com/fastening_systems_and_rings/aerospace/en/product_category.asp?cat_id=679

[Tinyfxds]

I'll have to get clarification from the customer.  They call for those two sizes that it must be a "locking insert"  but then it also says all holes must have a Helicoil. 

[Machineguy]

The locking helicoils are usually RED in color, but not always. They also go in a little tighter due to the locking bend.

Also ask the customer if they require  a primer in the holes before installing the insets.

[Tinyfxds]

I'm glad I posted this.  We do need a locking Helicoil insert which we didn't order and we didn't have an 8-32 Helicoil tap either.  So now our purchasing department is trying to scramble and buy everything we need before the material show up today

[88Matt]

There are different size helicoils for the same thread as well; i.e. there is more than one diameter 1/4-20 helicoil.  Make sure you have the right drill and tap for the helicoils you are actually using.

[Pilot Plant Supervisor]

And they make oversize Helicoil inserts if you screw up like I might have at one time...

[mikenaturalice]

There are different size helicoils for the same thread as well; i.e. there is more than one diameter 1/4-20 helicoil.  Make sure you have the right drill and tap for the helicoils you are actually using.

Where do you find this? Just curious I have never seen anything specced on the helicoil other than insert style, coating, length, etc. So you are saying there is a (for example) 10-32 helicoil that would require a different drill size and tap, not counting the varying drill size for material (usually very minimal) and the class of fit tap like 2b or 3b? I have a downloaded pdf of their (helicoil's) catalogue and don't see anything about this...

[88Matt]

Where do you find this? Just curious I have never seen anything specced on the helicoil other than insert style, coating, length, etc. So you are saying there is a (for example) 10-32 helicoil that would require a different drill size and tap, not counting the varying drill size for material (usually very minimal) and the class of fit tap like 2b or 3b? I have a downloaded pdf of their (helicoil's) catalogue and don't see anything about this...

Mike,

 

Basically there is standard and oversize.  Look up the helicoil you have in hand for the right drill and tap and you should be fine.  

 

We have had parts from one customer that wanted the oversize to begin with and the first time we ran them we drilled and tapped to the usual size we use. Needless to say the helicoils didn't go in... 

[jeff]

Here are the different styles of helcoils (now owned by Stanley):

http://www.stanleyengineeredfastening.com/brands/heli-coil/screw-thread-inserts

[mikenaturalice]

I'll be damn&*! Good to know. Are they new products or just seldom used?