Roll Form Tap vs Cutting taps Looking for thread forming that requires low torque

[mikemxparts]

I am running an M17 1.5 tap in aluminum at .500" depth. My Kitamura Mycenter1 does not have enough torque to spin the tap unless I bore the hole oversize. My question is: Does Roll Form Taping require more or less torque than cutting taps? Also if taps require less torque what type tap requires the least torque?

 

[hvnlymachining]

Cut taps require far less torque to drive. As for what requires the least, one of the members with more knowledge then I have will have to answer that.

 

[Finegrain]

Threadmill

 

[DouglasJRizzo]

In low torque applications thread milling is the way to go.
Superior thread form, tighter size control, better thread finish and easier on the spindle.

 

[Vancbiker]

I am running an M17 1.5 tap in aluminum at .500" depth. My Kitamura Mycenter1 does not have enough torque to spin the tap unless I bore the hole oversize. My question is: Does Roll Form Taping require more or less torque than cutting taps? Also if taps require less torque what type tap requires the least torque?

What RPM are you tapping at? If too low you might be successful with more speed to get into the power curve of the machine. IIRC, the Mycenter1 had a few different spindle speed options. What is on your machine?

 

[prime_mover]

Taps with a longer chamfer length require less torque, which is to say a plug tap will require less torque than a bottoming tap. The best taps for aluminum are the GLT8 (DLC) coated taps by EMUGE. The best taps are made by Emuge, period. They don't make an M17x1.5 tap though. If you are applying lube, Relton A9 works good and is non-toxic. Other than that: thread milling.

 

[mhajicek]

In aluminum you can run a pilotless threadmill in a competitive cycle time to drill and tap. There are some designed to mill the pilot while threading, and others that are combo drill/threadmill.

 

[BT Fabrication]

I am running an M17 1.5 tap in aluminum at .500" depth. My Kitamura Mycenter1 does not have enough torque to spin the tap unless I bore the hole oversize. My question is: Does Roll Form Taping require more or less torque than cutting taps? Also if taps require less torque what type tap requires the least torque?

for that, you would need a 15-20 hp motor and really low gear reduction to turn that one.
if its a small machine with a 7.5 or 10 hp, you wont cut it either way. as it needs something like a 3/4-10 that is 7.98hp before any gear box hp losses.

 

[Vancbiker]

for that, you would need a 15-20 hp motor and really low gear reduction to turn that one.
if its a small machine with a 7.5 or 10 hp, you wont cut it either way. as it needs something like a 3/4-10 that is 7.98hp before any gear box hp losses.

Can you tell us where your numbers come from???

 

[Conrad Hoffman]

Yeah, 17 mm is 0.67" and I could run that form tap in by hand (in aluminum) with a decent tap wrench, and I'm not producing very many HP these days! Now, there's the question of how fast you want to do it.

 

[Vancbiker]

A 5hp Mori with 8k spindle will tap M10 in aluminum and the book says ok for up to M12 in 1045 steel. I’ve not done that so no way to verify.

 

[DavidScott]

What RPM are you tapping at? If too low you might be successful with more speed to get into the power curve of the machine. IIRC, the Mycenter1 had a few different spindle speed options. What is on your machine?

I think my 2001 version with a 10 hp Yasnac motor switches "gears" at 3750 rpm, or really close to that. It has a two speed motor. The book says M24x3 in S45C with a minimum spindle speed of 150.

 

[mikemxparts]

On our Fadal we use thread milling but this Kitamura has a Fanuc 3M control and does not do 3 axis interpolation so I am limited to tapping. I need a newer machine !!

Yeah, 17 mm is 0.67" and I could run that form tap in by hand (in aluminum) with a decent tap wrench, and I'm not producing very many HP these days! Now, there's the question of how fast you want to do it.

I can't find a form tap for M17 x 1.5

 

[mikemxparts]

What RPM are you tapping at? If too low you might be successful with more speed to get into the power curve of the machine. IIRC, the Mycenter1 had a few different spindle speed options. What is on your machine?

I was tapping at 260 rpm. I didn't know the machine would have more torque at higher rpm's. It is a 1984 Mycenter1 Fanuc 3M dripfeed 8000 rpm max spindle, no gear box

 

[Conrad Hoffman]

Ha! You're right, no M17, just M16 and M18, at least in forming taps. There are a couple places that suggest they would make it. Probably not cheap.

 

[FamilyTradition]

I haven't done much thread milling myself, so I can't speak to that. However, someone close to me works for a large company that makes taps, and suggests that you check to see if the taps you are using have any radial relief. This may help with your torque problems - a lot of taps they produce have no relief on the lands, and such rub a bit all the way down. They've seen radial relief work wonders in certain applications.