2-Speed Gear Box a Necessity?

[JMFabrications]

I currently have an '02 VF2 with the standard options and the 2 speed gear head. I bought the machine used so it wasnt an option I chose but I have used it many times for drilling and tapping SS. Im in the market for a 2nd VF2 and found a nice '03 VF2 SS with the inline direct drive spindle. Im just trying to decide if I really need the 2-speed gear box on both machines for what im doing. 75% of my jobs are aluminum and the rest are usually 304 SS. The biggest holes I have tapped (form tapping) to date are 1/2" NPT in AL and 1/2"-13 in SS, at the low RPM the machine automatically went into low gear. At what point do some of you expert machinists feel a 2-speed gear box is in order? Haas advertises the standard spindle as 75 ft/lb of torque but the seller of the machine stated that with the direct drive the torque is much higher.....not sure if that is true or not. Any input would greatly help me with my next purchase!

Thanks,
Jim

[wms]

The Std VF2 SS is indeed a 75 FT/lb spindle, same as the normal non gear box machine....but a gear box machine is 250 FT/lb...you decide..

[Donkey Hotey]

You said 75% of your work is aluminum. If you buy a SS, then you'll have a single speed VF-2 and a super-speed VF-2: 75% of your machining capacity will be suited for aluminum.

If I only had one machine, the gearbox is necessary. If I have two machines, I'm not giving up anything by getting the super-speed. I then have a 'fast machine' and a 'torque machine'.

At least that's how I see it.

[JMFabrications]

You said 75% of your work is aluminum. If you buy a SS, then you'll have a single speed VF-2 and a super-speed VF-2: 75% of your machining capacity will be suited for aluminum.

If I only had one machine, the gearbox is necessary. If I have two machines, I'm not giving up anything by getting the super-speed. I then have a 'fast machine' and a 'torque machine'.

At least that's how I see it.

Thats kinda how I have been thinking about it to, its just nice to hear opinions from others. Thanks for your input!

[slatern44]

JM. If you get the SS machine just dont run it at 12K all day and night or you will be buying lots of spindle motors. I know of 3 shops in the northwest that have the SS machines and they all have replaced several spindle motors but they run their machines 24/7 and 12K motor cant handle. It kinda funny (but not to them) they all say we wish we would have got the 10K spindle, it's bullet proof.

[PBMW]

Slatern
Is that anyone in the Seattle area? I'd be interested in hearing who that shop is.
I know a shop that is all Haas and has had issues, but seem to be getting taken care of.
Actually, I can think of more than one...

[Geof]

Have you scanned through all the threads/posts discussing the Super Speed? Some people are not happy with them.

[toastydeath]

I feel a two speed is in order as soon as you put anything other than Al on the table or want to tap "serious" holes. All our good multipurpose machines at work have two speed heads.

The Haas at my college has a one speed head, and they suffer because of it. They can "show off" the machine to visitors and throw Al chips everywhere, but when it comes time to fix the fleet of manual machines or get some work done it falls short. If they had two machines, one high speed newfangled machine to show off and an old 80's Mori or Matsuura to get real work done, it would be perfect.

I think you are better served with a high speed machine, as long as you don't plan on throwing the other one away. If the majority of your business is Al, you already have the generic multipurpose machine, so it's time to invest your money in something that will reduce costs on 70% of your work versus adding capacity to that other 30%.

Edit: In a nod to Geof over there, I know nothing about Haas and can't speak to the quality. I am only making suggestions based on capacity.

[slatern44]

No, they are in the Portland and southern part of the state. The duty cycle on those spindle motors just cant handle 12K all of the time. I think the SS machines are fine but it seems that the shops that I know that have bought them think that because they have the big SS on the side of them they can just hammer on them. There not a "Super Sport" machine there a "Service Spindle" machine, just a joke haas guys.

[Geof]

Just a comment not aimed at any specific machine.

I wonder why 12,000rpm was chosen for a speed.

If you stick with 10,000rpm it is possible to get by without getting paranoid about balancing tooling.

If you go to 12,000rpm you do need to start getting fussy and making sure things are balanced.

So if you are going to have to worry about balanced tooling why not go for a 15,000rpm machine. Or even faster.

But I have to admit running a machine at 15,000rpm scares the pants off me. I have a VF2 with a 15,000rpm spindle and the noise it makes pushing a 3/4" two flute through 6061 at 15,000rpm and 120% spindle load is deafening. The machine can handle it okay but my nerves cannot.

[toastydeath]

Just a comment not aimed at any specific machine.

I wonder why 12,000rpm was chosen for a speed.

If you stick with 10,000rpm it is possible to get by without getting paranoid about balancing tooling.

If you go to 12,000rpm you do need to start getting fussy and making sure things are balanced.

So if you are going to have to worry about balanced tooling why not go for a 15,000rpm machine. Or even faster.

But I have to admit running a machine at 15,000rpm scares the pants off me. I have a VF2 with a 15,000rpm spindle and the noise it makes pushing a 3/4" two flute through 6061 at 15,000rpm and 120% spindle load is deafening. The machine can handle it okay but my nerves cannot.

You know, that's a really good question.

I think DMG had the same thought you did. If I recall correctly, they offer three spindles. 10k, 28k, and 52k (at a monster ~50 hp).

Your guess is just as good as mine, but it's probably just a pissing match.

"Our machine does 10k rpm!"
"Oh yeah, well ours does 12k!"
"12.5!"
"13!"
et cetera...

[Donkey Hotey]

The attraction of the SS is not just the spindle. Remember that it has a faster tool changer. It's obviously faster than the umbrella but it's also about twice as fast as the standard, side mount changer. It also has 1200 IPM rapids.

It would depend on the parts being run (number of tool changes, etc) but I think the SS does have its place. For all the reasons already discussed, I'm happy with my 10K, 2-speed VF-2. But if I had room and a need for more aluminum capacity, a nice, used VF-2SS would be hard to beat.

This talk about blowing the 12K motors is interesting though.