Peck Tapping, peck depth formulas.

[MotorCityMinion]

I'm looking for some data on peck depth settings when rigid tapping. At the moment I'm winging it. The machine has a very low HP/Torque rating and I was wondering if there is a standard / simple formula for calculating the depth of the peck relative to the tap size. Material considerations aside, does anybody have a formula or data they can share?

 

Thanks in advance, MCM.

[zero_divide]

IIRC Kenametal website had Power requirements for tapping in different materials.

Depth of the hole was not a parameter there.

 

Whats important is the diameter of the tap drill.

I also remember that tapping to 90% enagegemnt requires 3 times more torque than tapping to 70% thread engagement.

 

My HSMAdvisor can estimate tapping torque/power requirements, but it is not very precise. It tends to be more conservative than it really is. In other words if calculator says machine can handle it - it most probably will.

[Newbeeee™]

_{Good advice ref the torque requirements of full form tapping against truncated.}

 

_{For tuff mtl we usually peck at 1xD. This hasn't been arrived at from any specific thinking (could be considered as winging-it as well ) but it works for us.}

_{We're using soluble coolant (houghtons 795) and run it at 10% for everything on all mtl. Small thread, big threads, ally or steel, it works well for us.}

 

_{And good to see you around MCM!}

[Eric@HorsepowerInc.]

Newbeeee; I'm glad to see someone else is running Houghton's 795, we switched to that maybe 2 years ago and its been great. We run 795-B about 8% concentration and it pretty much rocks.

[Newbeeee™]

Eric - it is excellent but we're getting a huge amount of foaming on one machine.

It was a total clean-out/refill a couple of months ago, and we did it again with new coolant (both times) last weekend.

We have the anti-foam we spray on the top but 10 mins later and she's blowing again!

[Eric@HorsepowerInc.]

I am think maybe at 10% you are a little high, which could cause the foaming. We also have to add a slight amt of de-foamer in our high pressure applications, I'll get you the brand and amt we use shortly. I know we add very little maybe once a month to solve that, maybe a bottle cap or two .

[MotorCityMinion]

Happy Holidays MC brethren. 

 

A 10-32 tap with a .050 peck depth in 4140PH is pushing things a bit on our HSM Mikron.  I'm also using a 8-32 tap with a .032 peck (= to pitch) and that seems decent. We use an oil mister on this machine with Cool Lube 2210 EP and it works well.

 

Zero, we have the full version in our shop but it's time for an update.

 

Finding data for pecks depths with a tap is proving to be difficult. I'll see if I can pull something more academic from our tooling suppliers.

 

Keep the tips coming.

 

MCM.

[zero_divide]

 

 Zero, we have the full version in our shop but it's time for an update.MCM.

Please do. I have lots of new goodies there.

[zero_divide]

Nevermind tapatalk doublepost

[jlw™]

I usually just wing it too.  I've always started at 3 times pitch which is loosely related to diameter (smaller the tap, finer the pitch - mostly).  Of course, material is the primary factor imho.  Second would be the machine.  I've ran Grob's at 3000rpm in and 6000rpm out with 6mm carbide taps and I currently have Mazak's that don't like tapping any faster than 60 to 70sf regardless of size.

 

On a side note, I'm new to Mastercam (current Esprit user changing over).  How do you guys get Mastercam to output Q values for peck tapping?

[Newbeeee™]

I usually just wing it too.  I've always started at 3 times pitch which is loosely related to diameter (smaller the tap, finer the pitch - mostly).  Of course, material is the primary factor imho.  Second would be the machine.  I've ran Grob's at 3000rpm in and 6000rpm out with 6mm carbide taps and I currently have Mazak's that don't like tapping any faster than 60 to 70sf regardless of size.

 

On a side note, I'm new to Mastercam (current Esprit user changing over).  How do you guys get Mastercam to output Q values for peck tapping?

It's a post processor edit (usually).

If you search you may find it - if not put a question in the post processor forum.

[civiceg]

What do you guys have your backup distances set to and do you change them often? 

[slyym]

I've only peck tapped on a siemens controlled machines and just recently learned that Fanuc is able to do it as well. Is it just a Q in the G84 line? Can someone give me an example of how you use it?

[crazy^millman]

Q.2 would be a .200 peck. Easy to configure in the post if your post is not set up for it.

[Newbeeee™]

What do you guys have your backup distances set to and do you change them often? 

Assuming you mean the retract within the peck cycle - ie the 'swarf break' - 0.5mm & never changed it.

Its a parameter in the control

[civiceg]

Yes, your assumption is correct. I have always had it set  to 2 mm. Although I have never  done any production tapping with a peck. 0.5 seems like too small of an amount for a coarse pitch. Just curious, guess I could start decreasing it.