parting with a fixed steady disaster

[prepman]

Difficult to see what you have there @Kram - have you removed the topslide and made a solid qctp holder?
Of course you're right, how often does one use the topslide???
More details pics please? A qctp is on my wanted list, but one for the Triumph will cost me more than I paid for the lathe, and I would struggle to justify it.

As to QCTP I bought cheapo Chinzo 250-300 series 3/4" tooling. Not the best, but perfectly adquate though after cleaning some rough spots and cleaning grit and then greasing, Whether its available or at the price I paid ~£100 ???
I do use my topslide when thread cutting mainly, very rarely tapers.

 

[Erie Fred]

Pacemakers ....I didn't know they also made lathes?

Dis one right cheer:

"American" Pacemaker Lathes

And the Bullard:

20013 - 56" BULLARD DYNATROL HI COLUMN VERTICAL BORING MILL WITH 4 POSITION POWER INDEX SWIVELLING RAM HEAD & SIDE HEAD

www.raco.com

 

[Kram]

The smaller QCTP likely work just as well if you can mount it in a good place. Holders are much cheaper and the bigger ones dont have much more capacity.
I must have over 30 holders and its great to be able to swap a tool in seconds.

Old photo and not a great one.. the toolpost is mounted on a 12mm steel plate with a 30mm thick spacer tig welded to it, tapped m14 for the toolpost stud.

 

[prepman]

Dis one right cheer:

"American" Pacemaker Lathes

And the Bullard:

20013 - 56" BULLARD DYNATROL HI COLUMN VERTICAL BORING MILL WITH 4 POSITION POWER INDEX SWIVELLING RAM HEAD & SIDE HEAD

www.raco.com

Okly dokely....don't fancy having that fitted....one I've got is a bit unconfortable

 

[Erie Fred]

Okly dokely....don't fancy having that fitted....one I've got is a bit unconfortable

I would think most people (myself included) don't have enough powerline to feed it.

I ran 1" IC triangle inserts, with a 1/4" radius, negative rake.

One day roughing a big ring, had the turret boring the inside with a 3/8" deep cut (3/4" on the dia.)
as well as the side head doing the same on the O.D. both with .085 feed.
Chips were raining off nicely, blue "C" shaped.

And I wasn't a production worker, those guys really cranked things up.

 

[E T]

The smaller QCTP likely work just as well if you can mount it in a good place. Holders are much cheaper and the bigger ones dont have much more capacity.
I must have over 30 holders and its great to be able to swap a tool in seconds.

Old photo and not a great one.. the toolpost is mounted on a 12mm steel plate with a 30mm thick spacer tig welded to it, tapped m14 for the toolpost stud.

Do you have a way to lock the qctp to that spacer to prevent it from turning due to the tool pressure or is it only the clamping force of the stud and nut?
I found that, no matter how much I tightened down on the nut, the tool pressure from parting off turned the qctp a bit.
I drilled and tapped the bottom of the toolpost for two setscrews and milled a strip to fit in the top part of the top slide T-nut slot.
This did the trick, no more turning of the toolpost. The round dovetail on the bottom the top slide has resistance enough.
With my South Bend also came a heavy duty 4 way toolpost which can be used instead of the top slide. I love this toolpost. Very heavy and solid, but the biggest tools it will take is 10mm so my iscar parting tool doesn't fit.

 

[Kram]

I did initially have problems on the previous version. I would suggest you replace the clamping nut and include a recess underneath for ball thrust washer. This allows me to do it up much tighter and there is no chance of rotation.

Also to make sure the mounting faces are flat or slightly convex so the clamping force acts on the outer edges, rather than in the centre. Your compound does lok just slightly rounded, but if the screwed plate works, no need to change anything.

I dont like 4 way posts but you could always mill it out to take 12-16mm tools, plenty of meat there.

 

[E T]

I dont like 4 way posts but you could always mill it out to take 12-16mm tools, plenty of meat there.

I tried that but I need some different endmills for that. It's bl**dy hard steel and HSS Cobalt won't touch it.
I fear my small round column mill is not rigid enough for solid carbid endmills.

 

[Kram]

Hmm what mill is that? I have used carbide cutters milling in my lathe with good results.
You could temper or anneal the 4 way to make it easier before milling. Also use angle grinder to rough it out and only finish it with endmill. The top of the slot is only cosmetic too.

 

[dave h 2]

Pacemakers ....I didn't know they also made lathes?

Joseph Lucas made Pacemakers in the late 60'S, setting the points to 15thou was a swine to do.

 

[E T]

Hmm what mill is that? I have used carbide cutters milling in my lathe with good results.
You could temper or anneal the 4 way to make it easier before milling. Also use angle grinder to rough it out and only finish it with endmill. The top of the slot is only cosmetic too.

A Huvema 25-BF, which is a RongFu 25 with a Dutch name tag. I'm not too experienced at milling yet and I gathered that solid carbide endmills don't like vibrations and just break. I might get some and see how it goes.
Adapting that 4 way toolpost isn't a priority. Got plenty of toolholders for the qctp but I do like that South Bend toolpost because it's so ridgid. I have 4 10mm tools set in it and it's an quick swap with the topslide but I think my parting tool would benefit if it could fit in there.

 

[dave h 2]

Joseph Lucas made Pacemakers in the late 60'S, setting the points to 15thou was a swine to do.

I perhaps should explain that's a reference to medical ones, with a coil nearly the size of a small jam jar lid stuffed in your chest.

 

[prepman]

I perhaps should explain that's a reference to medical ones, with a coil nearly the size of a small jam jar lid stuffed in your chest.

Sorry my fault I've merged two threads and the joke hasn't been pickedup.

 

[prepman]

One thing I'd been meaning to do and @Kram 's setup jogged my memory. That was to make lever to replace the QCTP post retaining/clamping nut, just to make it spannerless. It's a 20 x 2 mm bolt with more exposed thread than is necessary, but I was reluctant to chop in down. Didn't want b'stardise the origal nut either,,,so I made a new one. 50mm long. I was amazed the internal thread was bang on with 1st attempt. Welded arm on it. I don't have issues with post slipping though. It is the correct 250-300 QCTP for 3/4" tooling. I need it to be infinitely adjustable so I can align full form threading tools with the topslide set at the appropriate half thread angle.