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QC toolpost for Atlas 618

Posted: Fri Jun 07, 2019 7:35 am
by SteveM
A friend just picked up a 6" Atlas 618 lathe. I was trying to steer him to a 9" South Bend, but at the price he got this one, I can't fault him.

He's going to use it occasionally to turn out small parts, and this will fit that bill.

I was talking to him about the lantern toolpost. He's seen my Aloris copy, but I told him it would be too big.

Littlemachineshop sells the 0XA, but the price is more than half what he paid for the lathe, and then he would have to stock up on holders (if you don't have enough holders and you have to keep swapping bits, it's not really quick change). There's the A2Z, but it is no longer being made.

He doesn't have a mill, so making his own toolpost and/or holders is not an option.

There's the option of using a 4-way toolpost, but I don't think I've seen them that small.

Any suggestions?

Steve

Re: QC toolpost for Atlas 618

Posted: Fri Jun 07, 2019 2:15 pm
by pete
It sounds like any QC tool post and holders are going to be expensive against what the lathes cost was. The A2Z were afaik made from aluminum anyway, so in my opinion a real poor choice of material for tool holding. Shereline makes a set that could be blocked up to work with his larger swing. But even it's $273 for the post and 3 tool holders.If it were me? I'd just machine my own 4 position turret type tool post on the lathe he already has. Not having a mill isn't an obstacle at all. A fly cutter for trimming the O.D. to size and an end mill along with a couple of drills and a taps for the center hole and the tool holding screws would do the whole job. Holding an end mill with a lathe chuck certainly isn't the best practice, but it would work well enough if he's careful about depths of cut and feed rates.The turret block could also have all it's surfaces machined to size without the fly cutter just by holding it with a 4 jaw on the lathe spindle.It would take some time, but that's usual when trading it for $$$. Keeping the correct shims together with each cutting tool they go with only needs to be set up once and after that tool changes are pretty fast.Those 6" lathes suffer from rigidity issues anyway, so using it's rocker tool post just further increases the problem along with the frustration for new people constantly adjusting them on every tool change.

Re: QC toolpost for Atlas 618

Posted: Fri Jun 07, 2019 4:15 pm
by SteveM
We found this one
https://www.wttool.com/index/page/produ ... ini+Lathes
Image

which gets him the block already made for less than $20 and then we just need to make the nut and locking screw / handle.

Steve

Re: QC toolpost for Atlas 618

Posted: Fri Jun 07, 2019 4:38 pm
by pete
Hard to tell from that picture Steve, but if the screw tips aren't yet turned down to at least the threads minor diameter I'd do that before ever using it. If you don't those tips will mushroom out just from the constant use making them impossible to remove/replace without cutting them off first.

Re: QC toolpost for Atlas 618

Posted: Fri Jun 07, 2019 6:44 pm
by SteveM
pete wrote: Fri Jun 07, 2019 4:38 pm Hard to tell from that picture Steve, but if the screw tips aren't yet turned down to at least the threads minor diameter I'd do that before ever using it. If you don't those tips will mushroom out just from the constant use making them impossible to remove/replace without cutting them off first.
That can be his first lathe project.

Steve

Re: QC toolpost for Atlas 618

Posted: Fri Jun 07, 2019 8:18 pm
by Wolfgang
SteveM wrote: Fri Jun 07, 2019 7:35 am A friend just picked up a 6" Atlas 618 lathe. I was trying to steer him to a 9" South Bend, but at the price he got this one, I can't fault him.

He's going to use it occasionally to turn out small parts, and this will fit that bill.

I was talking to him about the lantern toolpost. He's seen my Aloris copy, but I told him it would be too big.

Littlemachineshop sells the 0XA, but the price is more than half what he paid for the lathe, and then he would have to stock up on holders (if you don't have enough holders and you have to keep swapping bits, it's not really quick change). There's the A2Z, but it is no longer being made.

He doesn't have a mill, so making his own toolpost and/or holders is not an option.

There's the option of using a 4-way toolpost, but I don't think I've seen them that small.

Any suggestions?

Steve
My first lathe, from 1963 to 1992, was a 6" Atlas lathe which did sterling work for me. But the lantern tool post was enough to drive me to drink.

I made a triangular 3 slot tool post, as opposed to a square 4 slot post because I determined that with a 4 sided post the front slot, usually more or less parallel with the lathe centreline, would interfere with the tailstock or tailstock barrel when turning a piece between centres.

I made several such tool posts, keeping them populated with all commonly used tools, ground and aligned such that when the left hand edge of the tool post was set parallel to a face plate or chuck face using a 123 bock or parallel, that toolbit was in its operating position. Think threading, parting, left hand and right hand tools, grooving, and other tools that need close setting to give acceptable results.

With a little planning it is possible to do all machining operations to produce such a tool post, on the little Atlas lathe. w

Re: QC toolpost for Atlas 618

Posted: Fri Jun 07, 2019 8:26 pm
by NP317
I also started machining with a well-cared-for 6" Atlas lathe. Complete with a quick-change gear box!
Yes, the lantern tool posts were always a limiting factor.
I replaced that nice little lathe before making an alternative tool holder. I like the triangular idea!
~RN

Re: QC toolpost for Atlas 618

Posted: Sat Jun 08, 2019 8:44 am
by TimTheGrim

Re: QC toolpost for Atlas 618

Posted: Sat Jun 08, 2019 9:49 am
by earlgo
Steve: This is the tool post I use on the 12" Atlas. and a variation may be useful to your friend. Not exactly quick change, but a heckuva lot more stable than the lantern.
tool post
tool post
There are working drawings if you just PM me if you are interested. (Any one else, too.)
--earlgo

Re: QC toolpost for Atlas 618

Posted: Sat Jun 08, 2019 3:56 pm
by Harold_V
A comment on tool post types.
By choice, I purchased one of the square turret types when I started my business. It was made by O.K. Rubber Welders, and has 3° indexing, with a spring loaded detent @ 15° intervals. A marking plate on the perimeter of the head allows for selecting spacing between the detents.

I had been using a KDK where I was previously employed, and really liked that one could load various tools, but the speed of changing, a problem when specializing in small work, was troublesome to me. The four position indexing head is much faster, which is a huge factor when cutting time may be just seconds, with tool changing taking a much greater period of time. That goes away with a square head, which can be indexed and locked in a couple seconds. Remember, this was used for gain, where time is everything.

The negative of indexing heads is the limited number of tool types that can be used in any given setup. If both internal and external work are to be accomplished, it can narrow down the number to as few as three tools, all depends on how the head is set up. That teaches one to make a given tool perform more than one function. It also, on occasion, will permit a stub tool to be included, assuming cutting pressure for that particular tool is quite low, as it allows for but a single screw to restrain the tool. With that approach, I've made several setups that numbered five tools in total, and used that approach with success.

The last comment is that the square head does not serve well for one off type of machining, as there's usually never a required complement of tools in the setup, so you find yourself constantly changing tools. That's where the quick change posts really shine, in spite of the fact that it takes more time to make tool changes.

What I hope to see folks take away from this is that If one has options, make your choice according to how the post will be used.

H

Re: QC toolpost for Atlas 618

Posted: Wed Jun 12, 2019 1:52 pm
by whateg0
Harold,
That tool change time is what drove me to pick up and adapt a little Schaublin turret to my old machine. Before that I picked up a SB indexing turret toolpost. Of course, both of those options are too expensive for the OP, and the SB toolpost would be too big, but it demonstrated to me that the QCTP was not always the best option available.

Dave

Re: QC toolpost for Atlas 618

Posted: Wed Jun 12, 2019 3:57 pm
by Harold_V
whateg0 wrote: Wed Jun 12, 2019 1:52 pm but it demonstrated to me that the QCTP was not always the best option available.
Yep! In an ideal world, a person might find that having more than one type can be advantageous, which is really true when machines are operated for gain. Hobby use? May be no big deal.

Indexing time can be a real deal killer when cuts are of short duration and indexing is ongoing. The quick change really falls flat in that situation.

H