Need Help!- Live tapping

[Peter Gibbs]

Hi all , I guess this should be a no brainer ,but Im having trouble tapping 6 X 1mm threads in 12mm 6060 T5 alloy and the threads are 12mm deep,

I have several hundred to do. I have drilled M5 hole, I used 500rpm and a gun nose tap with Castrol EP690 coolant , and also with Rocol, the trouble is that the alloy is galling on the tap and buggering up the subsequent opperations and to top it off Ive brocken two new taps, yes there is room for the swarf to be pushed through during the opperation.

My best result was to slow it down to 300 rpm and use some old Trefolex but of course I have to stop and drop goop on each hole, some suggestions would be appreciated cheers peter

[extanker59]

Use a form tap instead of a cut tap.

[rbest27]

Originally Posted by extanker59 Use a form tap instead of a cut tap.

agreed

[littlerob]

Your title was "live" tapping, I am assuming you mean Rigid tapping since this is a mill forum. Not that the answer would change you still need to be using a form tap, But if you were referring to the "live" tools on a Lathe there might be some different variables. Robert

[Peter Gibbs]

Yerr your right , Rigid tapping, thanks for the responses form tap it is then, Ive never used one before I shall buy one today cheers Peter

[Geof]

Why are you tapping in 6060 why don't you get a decent alloy for machining?

Form tap is probably the best, but if you want to be daring and risk another tap go to 2000rpm and a very rich (20% or so) coolant mix.

I have found some of the sticky aluminum alloys behaviour better if you hit them fast. Of course sometimes it doesn't work and all you do is break the tap quicker.

[HelicopterJohn]

Hi Peter,

I have a little product that I produce for Radio Controlled Model Aircraft Transmitters. It is a balancer to change the CG of the Neck Strap button attachment point.

I have a HAAS TM-1P that I use to do this with. One of the operations is tapping some 3mm X .5 holes. I used a form tap and rigid tapping. I am using 6061T6 Aluminun with a rich coolant mixture with flood coolant like Geof mentioned. I have tapped several hundred holes and it has worked fine for me. I also use ONECNC XR2 software and use a peck tapping routine that one on the guys on the ONECNC form developed for use with the HAAS post.

I have attached a picture for your reference.

John

[Peter Gibbs]

Geoff would you belive that is the only mateial I could get off the shelf, without special order that is , next time ill know better,

John thanks for that are you saying there is a special post for the peck tapping ? I run XR2 as well , and thank you for the input,

I just spoke to my tool rep and he is sending a two flute tap free for me to try, designed for alloy has anyone tried this , but I will buy a form tap as well cheers peter

[engine tech art]

I do alot of taping with m6 and the only way i found works is pec taping but you have to go to your parameters and turn on repeat rigtap to a 1.
Then make your coolant rich and the coolant should be oil base not synthetic.
Mineral base has better lub properties. if you don't have a post just copy the tap program and past below and just change the depth.I learned the hard way many taps. I had to go 1. deep blind hole, 8 holes, 3 pec's.

Art

[littlerob]

Oh yeah if you have never form tapped keep in mind you will need a bigger hole size, it is in Machineries Handbook. I would tell you but I took the day off, and it is at work. And here I am online with a bunch of machinists? Robert


5.6 MM

[HelicopterJohn]

[QUOTE][/John thanks for that are you saying there is a special post for the peck tapping ? I run XR2 as well , and thank you for the input,
QUOTE]

Yes, I downloaded the modified post from one of the threads on the CNC Zone. Just do a search and you will find it or just ask about it and someone there will direct you to the source. It will go to 3 levels.

If the 2 flute tap doesn't work for you I would try a FORM Tap as it has produced really nice results for me with a rich coolant mixture.

John

[kojack]

threadmill ?