No gloat because of no pictures but......

[Black Forest]

I just bought two retractable threading tool holders for my Multifix C QCTP.

One for internal threads and one for external threads. These things are massive. All you have to do is pull a lever and the threading tool is retracted from the threads you are cutting. So while the carriage is returning to the start of the thread you are cutting you can dial on the next pass either on the cross slide for plunge cutting or on the compound if you are threading that way.

I haven't tried them yet.

Saves time the same as Sir John's swing up tool holder.

Anyone on here ever use either of these toolholders?

[DannyW]

Gewinde Rückzughalter - Quick return threading tool holder.

Good evening Black Forest,

Are these the ones you are writing about?

External type

Internal type

Regards,

Danny

[Black Forest]

Yes those are the ones.
So have you used this type of toolholder?

[DannyW]

@ BF:

Short answer is, no, I haven't used them.

Although I have a few of both types somewhere in storage for a Multifix type B.
The switchover to Multifix altogether, on the designated lathe was postponed.
I made eight new holders for the QCTP that was on the lathe already. And in doing so
my Multifix QC threading toolholders have never been used.

They should function as the cat's meow, though!

But not everybody has access to the dedicated threading inserts they use (Ifanger – Komet?).


And one remark I have (maybe you can help me with that later) is, that the lever has to be manipulated
with care if you have play in the cross slide nut.

To demonstrate this, do the following:

Crank the cross slide in the direction away from you.
Now grab the tool-post and give it a good push forward!

You will see that the slide jumps forward!
So, on a lathe with some play in the cross-slide nut, if you shove the lever hard forward (on the Multifix setup toolholder) the threading tool will advance a lot more added to your dialed-in DOC (depth of cut)!

Just something to look out for.

But other than that, I think you will be pleasantly surprised at the ease of use.

Please report back later with images and hands-on experience.

Regards,

Danny

[Black Forest]

I did the test you mentioned and my cross slide doesn't move at all when I push or pull on the lever as hard as I can. I yanked it as hard as I dared without damaging the lever! The readout on the DRO never changed for either holder.

I think my cross slide is heavier than I am in KG's. My lathe is quite heavy.

Yes the actual thread cutting tools are hard to find and quite expensive. I bought one for 60 degree's and one for 55 degree's. I had already bought the threading holders so I had to buy the cutters. 161 Euro's apiece but they should last me the rest of my life if I don't live forever!

[DannyW]

Lucky you!

Don't go all King Kong on the lever, but doesn't the initial push against the toolpost result in it taking up slack and jumping a bit forward?

My cross slide nut is shot though but I would guess that a lot of folks can mimic this behavior, even with minimal play in the nut.

Test it, but understand the procedure!

- Crank the cross slide away from you.
- Don't back up the lever in the other direction!
- Zero the DRO or place dial indicator against cross slide.
- Give the toolpost a hard push forward.

Report results.

If you push a second time, or more you will get no movement, because the slack is now gone, until you crank forward another time!!

Regards,

Danny

[philbur]

I think they are no quicker that cranking back on the cross-slide. They are possibly less prone to making an infeed error, less so if you are using a DRO. If you do an awful lot of threading then they may be worthwhile, otherwise I think they are a bit of a luxury.

I'm amazed that you get no change on your cross-slide DRO when you yank on the toolpost as hard as you can. What size lathe do you have?

Phil

[Black Forest]

It is not huge but it is fair sized. It weighs 6600lbs.

I went and tried it again making sure I had fed the cross slide in and not backed it out. The cross slide does not change when I push or pull on the lever of the threading tool. Even when I slam it up against its end travel.

[philbur]

Is that with a 0.01mm resolution on the DRO? Do you have some form of backlash adjustment on the feed-screw? Do you have the gib set particularly tight?

Just curious as to how your machine achieves zero backlash.

Phil

I went and tried it again making sure I had fed the cross slide in and not backed it out. The cross slide does not change when I push or pull on the lever of the threading tool. Even when I slam it up against its end travel.