My Lathe project; might CNC it one day

[Stevie]

First off mill the block to sizes
I used the big lathe with a 4 jaw to make te first hole very close to the center height; then went in the vertical mill; I bored close to the final size and measured to the outside edges; moved the block till dead on
Flip it over and repeat

[Stevie]

Managed to slip back again to the shop

New spindle set into the tapered roller brg; this will be finish cut to fit the chuck under power in the brgs; the collet taper and some small detail can be done then too; this will ensure accuracy

The back view; still need to make the locking threaded coller; but the 1.000" dia is finished ready for the drive pulley; this is longer than the single 8 step pulley I was using to allow for a timing pulley to be added just behind the lock coller; this will be for indexing the spindle with a 310oz/in stepper 3-1 reduction
Note the shallow keyway 0.125 deep 0.1875 wide I kept it shallow because the hole through is quite big 23/32" dia

Next will be the lock coller and mod the pulleys; the extra depth in the bores is for the oil seals 55mm 38mm 8mm

[arvidb]

Let's see if I got this straight;

you first used a lathe to mark the hole position and get a start hole, then used the mill to do the actual hole?

I'm unclear about the different ways to make a hole - there's the normal drill (spiral or "twist") for small "crude" holes (I've heard they don't make a hole really round), then the reamer for finishing the hole off (better surface quality, a round hole, and better tolerance in dia). Is this correct?

And then boring... which is actually like turning but done on the mill? In a manual mill I guess one would use an offset boring head to get the correct hole size? Is it possible to only use the boring bar in a CNC mill and still get variable hole size?

I could really use a tutorial on how to make holes in metal

How good diametric and positional tolerances can you get with the method you used?

Thanks for the help,
Arvid

[Stevie]

I used the big lathe because it's easier to bore a big hole than the miling machine; I drilled about 1" dia first then took 3 cuts to 1 13/16" dia
This would have taken a great deal of time with an offset boring head in a mill; the block is 5 1/2" long
The mill finished the brg and oil seal dia just 0.880 deep; behind is a second bore to clear the inner section of the taper brg 2" dia 0.187 deeper than the brg depth

I got the 2 sides within 0.0005" thats close enough for me

[Stevie]

Newest images
Here is a side shot of the new head finally bolted to the bed; yes it's quite a bit longer and has already caused a few thoughts about the layout under the bench
The head is 1/2 filled with #30 oil ready for the machining of the chuck location diameter; bearings are preloaded too



Above shot; once again that trusty bronze has shown up; this is the preload nut; 2 holes for a tommy bar and 1 lock set screw; just behind it is a collar for the oil seal to run on; it also spaces the inner bearing race


I've lost a bit of travel with the chuck and new spindle; but without the chuck I gain a few mm's
The old collet setup will not be reused; I intend to make a new ring to fit the same diameter as the chuck; this will have an inner thread and a push ring to lock the collets tight; a simple pin wrench will fit it

Now for a question
I'm running it now with a 1/2hp 120Vac motor
If I got a sweet deal on a 1/3hp do you think it will be enough power; remembering the new tapered roller brg setup; the old setup had very little resistance to rotary movement; now we have preload to consider

[Ken_Shea]

If I got a sweet deal on a 1/3hp do you think it will be enough power

Maybe Steve if it is a high torque type but I have my doubts if it is not, since I know you are going to be cranking the RPM at times on your unit. Not that big a deal to just try it and see how it goes.
I am assuming cheap is spelled "Sweet"

I put one on an old lathe years ago that was 1/3 HP high-Torque and it amazed me the power it has in starting up. Came off a pin setter from a bowling lane.

How does tyhe head mount to the bed?

EDIT:
BTW, and once again, nice work.

Ken

[Stevie]

There are 2 8mm grade 8 socket head cap screws up from the bed bottom; but this will have to be increased now; I'll add 2 more plus a rear support

Also I forgot to add; the driven and drive pulleys have swapped places; I'll re-make the drive pulley with bigger changes to the steps; this will space the speeds apart a bit more; there will be 8 regular speeds plus any differentals

[WayneHill]

Look for a motor at http://www.surpluscenter.com/

Also think about using a DC motor with a DC variable drive. No pulleys needed. Well, maybe high and low gear.

[Stevie]

Basically the new head is finished as for the running part; it sure cuts nice; there was a small sound for the brgs at first; but I think I had a bit too much preload; or it could have been a very small chip; piece of hair; who knows??
I ran it for 1 hour with a temp sensor; hit 49dgr; which is why I think it needs an oil cooler; at 6000rpm she is sure winding out; this is still 3000rpm from max speed with oil



Here is the head with chuck fitted and cuts made

Wayne; I've looked into VSD; might one day

I was thinking of buying a small drill press and removing the motor; for about 80bucks i can buy a 8" benchtop drill; i can't get a 1/3hp for $80 as just motor

[balsaman]

Very, very cool.

Eric

[Stevie]

Thanks Eric

[Ken_Shea]

1/3hp for $80 as just motor

Are you serious Steve, wow!, any scrap yards around you?, how about a well digger or plumber, ask if they have any old jet pumps that maybe the motor is still good, these are high torque but do have a 4 bolt flange on the face for mounting, sometimes that can come in handy, sometimes not. If you need something shipped from the states let me know. I can probably round you one up here and ship it to you for about $50 or so maybe even a 1/2 HP.

Ken

[Stevie]

Well the rest of the drill press would be worth making something out of it too; the spindle maybe just the ticket for another project

Remember $80 Canadain is about $50 American

[Ken_Shea]

Well the rest of the drill press would be worth making something out of it too; the spindle maybe just the ticket for another project

Thinking ahead, that's smart.

I can get a motor for about $10-$15 the shipping of about $35 is the killer.

Ken

[Ken_Shea]

which is why I think it needs an oil cooler

How about machining some thin cooling fins into the sides of the head or trying oil additives that cut friction?

I use CPR brand here, it is not in Canada but I would think there would be similiar products there or I could mail you enough to try for FREE



Ken

[Stevie]

Hi Ken

I can't; there is too much stuff to be bolted to the head; there will be a 3 axis milling attachment; plus the bridge to the tailstock for another Z axis

I can try an addative; I even think I have a free sample somewhere

[ynneb]

Because lathes don't interest me, I haven't read this thread till now. Boy have I missed out.
Stevie, you have done a magnificent job. The photos you have posted are fabulous too.
Tremendous effort.

The Lathes looks too good to use. You wouldn't want to dirty it.

[Stevie]

ynneb

Thanks; ho it's been plenty dirty; I use a shp vac every time I'm finished

[Stevie]

Hey Ken

Good news

The 1/3 HP will drive it just dandy
I got a 8" drill press for $69.95; so in effect I got a 2" travel spindle with 3 spoked handwheel (if this were laid down and the back cut off; I see a tailstock of sorts) a new 1/32-3/8" chuck with Key; the 1/3HP motor; a nice 115Vac switch; small cast iron base with column and rotatable table (must be another use for this too)

[IJ.]

Originally posted by Stevie
Hey Ken

Good news

The 1/3 HP will drive it just dandy
I got a 8" drill press for $69.95; so in effect I got a 2" travel spindle with 3 spoked handwheel (if this were laid down and the back cut off; I see a tailstock of sorts) a new 1/32-3/8" chuck with Key; the 1/3HP motor; a nice 115Vac switch; small cast iron base with column and rotatable table (must be another use for this too)

Stevie: If you were really clever (and going by your Lathe you are) You could make a mini turret out of your left over drill parts !