[Guldberg]

This is how it started (except for the length) and how it ended

From CNC

From CNC

The frame for the enclosure

From CNC

I recieved my new KX3, i decided to open a new thread for it to post mods, tweaks and various stuff http://www.cnczone.com/forums/showth...654#post588654

[vishnu]

Excellant show of Workmanship with good & simple design. Your machine build has inspired me to make one. Can you just breif me the exact specs of the machine and the constant possibility of machining Steel on long run. As i am a novice in building machines please share your ideas which would be really helpful in building one.

[Guldberg]

Finally some update. I droped off the base at my uncles mid december, but nothing has happend until today, so lets just say that it has now "aged". Anyway, they have a nice big 4 axis machine, capable of machining workpieces up to Ø900x900 and 1200kg.
Here is a picture of the first setup, machining the bottom and ends

From KX3

From KX3

Envy...

From KX3

From KX3

Second setup

From KX3

Machining finished

From KX3

Fits right in a punto

From KX3

And now the best part, this gonna make me feel a little better when I makes mistakes in the future. The machinist with 16 years of experience with this machine managed to ramp the face mill right into the workpiece. Its not ment for ramping so the material in the center is more or less just "pushed" away. Some serious forces, the machines is rated 380v 87amps!

From KX3

[svenakela]

The difference is that it will now take another 16 years before he makes that mistake again.
Looks very good.

[ebrewste]

I've been following this since you started this thread. You are doing great work and I am impressed by your persistence. I'm looking forward to your further progress.

[digits]

Very nice work

Were those setups done on the machine, or were they done with the fixture and lathe-bed horizontal on a bench, and then just hoisted on to the machine?

I'm glad you got it home safely - from those pics , an E-stop in your car could have left you with a lathe bed for a head!

[ZipSnipe]

A lil bondo will fix that screw up. Its looking great so far, love your enclosure.

[handlewanker]

Er, Guldberg, was that a counterbore he decided to give you for free or as they used to say in UK when someone made a mistake at the start, "a false start" LOL.

You could always just drill a hole through the centre of the "cutout" and bolt something to it.
It's in the right position to hang a light on.

I love that tool cabinet with all the "goodies" hangin there, I bet you've got one in mind for yourself too.
Ian.

[Guldberg]

Thx guys.

The machine has interchanging pallets, so the pallet just roll outside the machine where you can access it. We decided to add a eye bolt (?) to the end so we could lift it with the crane in the second setup. With both the drill and the tap already in the machine it only took like a minute anyway. Got to get me one of these one day:-)

I did a quick mount of the rails and the x-axis carriage. We made cut along the rail stand off's, so it was a breeze to dial in the rails. Wont be long till both axis are running, so I have to start fabricating the headstock soon

From KX3

[Willyb]

Great job designing and building your CNC Lathe. Can't wait to see this machine in action. Keep of the good work.

Willy

[vishnu]

Hi,

Good progress, whats the spec of the motor. What is the approx weight of the machine with motors, tool changer with Chuck. I think for the solid machine you are building a lot of strength on the base is required if machining mild steel at good speeds. What do you think can be the cut depth that you can go in MS ? . I have seen many lathe builds but not as professional as yours, love to start one bases on your designfor my personal use ASAP.

[Guldberg]

The motor are rated 3hp. I have no clue of the weight, but the base itself weighs approx. 90kg. My best guess is that the total weight of the machine will end up at around 300kg.

As i have not done any calculation on this, I dont know the capability of the machine yet, but I designed it to be more ridgid and with more power than similar sized lathe, so i hope that it will performe well

[vishnu]

Good 300 Kgs of machine weight is enough & equal to commercial machines available in the market. i think it should not vibrate as 3 Hp motor will slice up metal without problems. Have you thought about having a Hydraulic power chuck, which would put your machine at par with the commercial machines. In India the minimum price for a CNC turning centre is around $20,000/- , i cannot invest as i have already invested for Mechmate CNC router which is 95% complete and i have orders only for small lathe jobs for which a commercial machine is not required. I am eagerly waiting for the test results from your machine to start, i am planning to start with the ATC sometime this month prior to building the machine.

[Guldberg]

I just "ordered" a piece of Ø150x250mm steel for the headstock spindle housing. Here is the basic idea, comments are very much appreciated

From CNC

[S_J_H]

This setup was used by Mike.......(can't think of his surname), to build the CNC lathe bought by Rube in the USA, when Mike decided to build a Horizontal Borer from scratch.
Ian.

That would be "Steve" :wave:

That was my early setup and one I probably should have stayed with.

[S_J_H]

The plain bearing is a remarkably simple and extremely accurate way to go. I machined my own bronze shells for my SB9A. The original cast iron bearing surfaces were trashed when I took possession of the lathe. I did a quasi line bore to the headstock to remove enough material to fit new bronze shells. I converted it to a top oiler- total loss system which means constant fresh clean oil. I reworked the oil drainback grooves in the headstock for better return flow so it would not spit any oil at speed and it runs super clean.
I did not split the bronze shells and instead relied on the split headstock to crush/distort and provide the needed LEMON shape of the bronze shells for proper control of oil "whirl" and "whip". My bestest .00005" indicator shows almost no movement of spindle runout. I run it at about .0007" clearance.
I recently removed the spindle and after 1year of use the bearing shells looked EXACTLY as when I first machined them. I could not see any wear whatsoever and not even any markings of any sort . Astonishing!
The spindle will run at 1500rpm and just be warm. It's just a little old southbend flatbelt, but it sure does give a nice surface finish.
I'm a big fan of plain bearings and a pressurized system would be really neat!
Steve

[svenakela]

The plain bearing is a remarkably simple and extremely accurate way to go.

I agree on that. Every car engine got 'em.
They also have a greater area to take the load. Roller bearings are supernice, but may not be needed. I've said it before though - I do like overkill engineering.

[georgebarr]

In post #260, you machined your own bronze bearings. How did you get that groove on the inside of the bearings? What maching process was that?

[S_J_H]

Steve - I didn't realize bronze bearings could work so well. I'm re-thinking my design now. I'm surely going to go with the separate spindle-in-headstock idea, but maybe I should drop the AC bearings and go for bronze... Could you tell me what you're using for a thrust bearing? Would higher RPM be a bad idea with your setup?

Jason, I still am using the factory ball thrust bearing. Here is a link with further details- http://www.lathes.co.uk/southbend9-inch/page3.html
There is a fiber thrust bearing on the opposing side. Many now replace that with a needle bearing assembly.

Rpm is limited without using a pressurized system. I would not feel very comfortable pushing it beyond 1500rpm. Unless I was doing some small diameter work with carbide tooling I don't have much need for much more rpm out of it.

Steve

[vishnu]

Hi,

From the drawing i see that the spindle head can be removed without removing the head stock as in a commercial machine. What is the wall thickness of the spindle shaft and what is the bearing that you plan to use.

Vishnu