Threading back to front question

camhead420

Cast Iron

Joined

Nov 22, 2019

• Jan 17, 2020

• #1

Hi,

I have a little part that i am trying to run in one operation on a doosan with live tooling. Can i thread from back to front? and have normal threads?

 

L

Larry Dickman

Titanium

Joined

Jan 30, 2014

Location

Temecula, Ca

• Jan 17, 2020

• #2

you'll need to reverse the spindle, otherwise they'll be left handed

 

camhead420

Cast Iron

Joined

Nov 22, 2019

• Jan 17, 2020

• #3

wont reversing the spindle change my tool setup?

 

L

Larry Dickman

Titanium

Joined

Jan 30, 2014

Location

Temecula, Ca

• Jan 17, 2020

• #4

mr.greenman said:

wont reversing the spindle change my tool setup?

Click to expand...

ya, you'll need to turn the tool upside down

 

EmGo

Diamond

Joined

Apr 14, 2018

Location

in the middle of the edge of the center

• Jan 17, 2020

• #5

Larry Dickman said:

ya, you'll need to turn the tool upside down

Click to expand...

Can you do that with a Jap/Korean turret ? Otherwise, they make a special drop-head threading holder for reverse-rotation back side turrets. As Larry says, they are upside down, But the insert still has to be on the centerline of the part

 

camhead420

Cast Iron

Joined

Nov 22, 2019

• Jan 17, 2020

• #6

thanks guys,i knew i was over thinking it. i read a couple threads and someone suggested using an id threading bar turned over.
I think i will try that first.

 

V

Vancbiker

Diamond

Joined

Jan 5, 2014

Location

Vancouver, WA. USA

• Jan 17, 2020

• #7

EmanuelGoldstein said:

Can you do that with a Jap/Korean turret ? ....

Click to expand...

Most all can. You just switch the clamp wedge position.

 

camhead420

Cast Iron

Joined

Nov 22, 2019

• Jan 17, 2020

• #8

Yes it can, but the insert would set back and i would have to hang the bar out to far.

 

M

mmurray70

Stainless

Joined

Jan 11, 2003

• Jan 17, 2020

• #9

I do this all the time with no issues. My very old mazak lathe uses "right side up" tooling on the back. Normal RH threads starting close to the chuck and moving away from it. Spindle in reverse and tool right side up.

The initial plunge is a little harder on the tool, but just program more passes then you normally do and it will work fine.

 

Ox

Diamond

Joined

Aug 27, 2002

Location

Northwest Ohio

• Jan 17, 2020

• #10

mr.greenman said:

thanks guys,i knew i was over thinking it. i read a couple threads and someone suggested using an id threading bar turned over.
I think i will try that first.

Click to expand...

That would werk if you are just using a basic 60* single point insert, but not if you want to use a cresting insert.

Trying to git a full thread all the way to the undercut on your part would be much easier with a cresting insert.


--------------------

Think Snow Eh!
Ox

 

Matt_Maguire

Stainless

Joined

Oct 17, 2011

Location

West-Central Illinois, USA

• Jan 17, 2020

• #11

With chuck turning CCW → tool cutting away from chuck → then operator side of the part insert is upside down & from the backside of the part insert is right side up = both make right hand threads.

Good luck,
Matt