[MarkSerbu]

Okay, so I've got a part that I used to run on my Mazak horizontal mill (now sold) and am now running on the Haas VF-4SS. I'm thinking that the "SS" is a joke, because there's a bit of 3D machining on this part that was amazing to watch on the Mazak and is painful to watch on the Haas. It nearly stops when changing directions! I've changed the program to put arcs where there were 90-degree changes in direction, but it doesn't help much. My Haas Factory Outlet will kindly turn on the high-speed machining option for a mere $2300 (Hmmm.....I thought buying a SUPER SPEED machine meant that it was already high-speed!), but I have my doubts as to whether this will help. If it merely changes the look-ahead from 40 to 80 blocks, that won't do squat for the slowing I'm seeing during direction changes. I'm thinking that this machine just isn't very stiff, and it needs to slow to a crawl around turns just to keep the tool from gouging. Has anyone paid to turn on this option and felt it's worth it? Will the HFO deal on the price?

Thanks!

[KenFoulks]

I have seen high-speed machining (HSM) solve many problems. You can try HSM for free by entering a 1 into parameter 315, bit 4. Any option listed in parameters with a 0T to the right of it, has a 200 hour free trial available. You can also use G187 to change setting 191 and 85 on the fly. More information can be found in the operator's manual and on the Haas website.

[mactec54]

MarkSerbu

You can turn it on your self, to try it all there machines have 200 hrs of time for the extras, so you can test it, then turn it off to save the hrs

I have it turned on & find it smooths the machine movement, what software are you using for your cam, this to can play a big part as to how the control will run your part

How can you compare the Haas VMC to the Mazak Horizontal, the Mazak is a much more expensive & different machine, spend the same amount for the same model/type Haas & then compare

[MarkSerbu]

Damn....the tech guy turned on the HSM when the machine was installed 2 years ago and of course the 200 hour trial is long gone. I use a few different CAM packages (including Mastercam X2), but in the problem areas I've checked the differences in how the machine operates by drawing my own toolpaths. I've ruled out the program as being the culprit for the slow, jerky function of the machine. I've read of companies that use Haas machines to do 3D machining of aluminum on a production basis, and I can't imagine they're using a VF-4SS from what I've seen. I appreciate the responses so far, but is there someone out there who can say, "Yes, I've paid the $2300 to turn on HSM and it's like night and day!" or "Hell no! Save your money!" ?

[extanker59]

We have had it from day one. Doing a lot of 3D. Even going slow (30 IPM), it doesn't do very well and hasn't from day one. It's acceptable for our parts but nothing like the mirror finishes in the pictures.
I have one suggestion though, could it be backlash in any of the 3 axi? I know ours needs to be adjusted but since this is from the very first and hasn't gotten worse I have my doubts about it fixing the problem.
Machine not as tight as the Matsuuras I used to run but not as expensive either.
Overall I still like the machine.

[Matt@RFR]

I do a lot of 3D machining on my VF-2ss, but I bought HSM with the machine so I can't say what it would be like to not have it. (I could turn it off, but I'm not going to)

I feed 1/8" ball endmills at 150 IPM all the time on small, irregular, fine semi-finish passes and the machine does just fine. I've been as high as 300 IPM with larger endmills doing semi finishing passes and it looks just like 300 IPM doing 2D stuff.

Like Ken said, G187 Px Ex.xxx can have a huge effect on how a toolpath runs, but be careful with that. Getting too aggressive with those settings will let the machine round corners quite a bit and possibly gouge your part. I only use G187 during roughing and semi finish passes, never finish passes; Finish passes are done with the default settings.

The attached part was finished on the surfaces with a 1/8" 3 flute ball endmill at 90 IPM and .003" stepover. Those specific toolpaths took 6.5 minutes to run. That's a pretty damn good finish for such a fast cycle time in my opinion.

[extanker59]

The inside of your part looks like the outside of mine. The outside of your part is great. Nice part.

A .003 stepover and 60 IPM is my norm with a 1/8" ball 2 flute in titanium and 17-4 SS. Not satisfied. What is the default G187 setting (I've changed mine so much I've forgotten)? I'm talking about settings 85 and 191. Mine are .025 and Finish respectively.

[KenFoulks]

The Haas factory and your local HFO are happy to help resolve your issue. Your HFO will be contacting you shortly, let us know how it turns out.

[Wizzard of H]

Turning on HSM is not just changing lookahead from 40 to 80 blocks.
HSM really is all of the things needed to make lookahead work.
That gives 80 blocks of lookahead.
Without HSM, you don't get any effective lookahead so short strokes keep the feed from getting very high.

[Matt@RFR]

What is the default G187 setting (I've changed mine so much I've forgotten)? I'm talking about settings 85 and 191. Mine are .025 and Finish respectively.

Mine are set to .025 and Medium. That's how it shipped from the factory. I just tried and in MDI, G187 P1 E0.050 does NOT change settings 85 and 191, atleast the control doesn't show the change. I guess those settings are strictly to control the defaults so when G187 with no other inputs are programmed, the control goes back to what settings 85 and 191 are set to.

I'm thinking G187 P2 E0.025 (or just make setting 191 to medium) will make a big difference in your machine. I know when running something like a 1" indexable endmill at 400 IPM, going from medium (P2) to rough (P1) makes a big difference.

Nice part.

Thanks! Those are tricky little parts. The skinny sections are only .047" thick with the spaces in between being +.002" / -0.

[Pondo]

If 3D and HSM machining was the primary job of the machine, then the SS model is not the correct one for the job. The SS has a double lead ballscrew that is not suited to fast starts and stops, just high speed rapids. It's like having a tall first gear on a drag bike - it doesn't launch hard.
The standard VF-2 will outdo an SS model in surfacing parts where you need a fast change of direction and are not concerned with high rapids.

[extanker59]

If 3D and HSM machining was the primary job of the machine, then the SS model is not the correct one for the job. The SS has a double lead ballscrew that is not suited to fast starts and stops, just high speed rapids. It's like having a tall first gear on a drag bike - it doesn't launch hard.
The standard VF-2 will outdo an SS model in surfacing parts where you need a fast change of direction and are not concerned with high rapids.

Now THAT is interesting! I didn't know that!

[extanker59]

Re-reading it. Can you clarify: "The standard VF-2 will outdo an SS model in surfacing parts where you need a fast change of direction and are not concerned with high rapids."
Outdo in what sense? Time? Surface finish? Accuracy? We just ordered a VF-2ss and it might be in time to switch.

[Pondo]

I was looking at a VF-2SS when I bought my standard VF-3. I was cutting only aluminum and plastic prototypes and did a lot of 3D surfacing with small tools, so I needed a machine that could change directions quickly. The SS models have a wider pitch ballscrew that gives it the higher rapids, but the finer pitch ballscrew on the standard machine let it change direction quicker. It's like driving a car in first gear - your top speed is low, but it gets there fast.
It all depends on what is important to you. The SS has a lot faster chip-to-chip time and there are time savings with the high rapids, but for surfacing at high feedrates they can not do what the standard machines can.
Take a look at what kind of work you are going to use the machine for and get the machine that best fits it including SS or not, spindle speeds, memory needs, air blast, HSM, TSC, pallet changer, tolerances, production volume, cycle times, complexity of the parts, etc.
Try not to get sold on a machine that may sound great but doesn't suit your work.

[extanker59]

Thanks.
We're kind of stuck between a rock and a hard place. We do a lot of surfacing (on most parts it takes up the bulk of the cycle time) but it's with small tools where the higher RPM is desired.

[Pondo]

I had the VF-3 built with a 15K spindle, but I believe I could have gone up to a 25K. I stuck with the 15K so I could use regular collet holders and not have to go to balanced or shrink holders.
The majority of the cycle time in my machine was surfacing with tools 1/2 - 1/8" and engraving with a 1/32 BNEM in plastic and aluminum.

[extanker59]

Just saw an option for 15,000 RPM on the standard VF-2. Can a Haas representative chime in with an opinion? Making medical devices/instruments in 17-4PH and Titanium. Using 1/8" carbide ball endmills and smaller typically.
Concerned about poor finish in 3D operations rather than chip to chip speeds.

[KenFoulks]

The absolute best machine for high-precision/fine-finish 3D/mold making is the VM-series machine. As Pondo stated the chip-to-chip time on the SS is superior to non-SS machines, because of the higher rapids and fast tool-changes. If your machining for three hours with one tool change you will not realize the benefits of an SS. If you make one 3D part per year, you will not realize the benefits of a VM. The VF-2 and the VF-2SS, when HSM is turned on; perform nearly identical and almost as well as a VM.

extanker59: I would recommended the VM-2 for you, based on your last post. The VM may have a higher base price, but a VF-2 with all of the options a VM-2 has standard; would cost more.

[MarkSerbu]

Damn, I wish I'd known this BEFORE I bought my machine! I ordered the SS package because it included a lot of things that I was going to get as options anyway and turned out to be a better deal. Since we always run the rapids at 50% I guess the high-rate ball screws were a waste. So far we only have this one part that's got 3D machining on it, and we'll probably be outsourcing it anyway. Would be nice if I could get Haas to temporarily turn on the HSM again so I could do an A to B comparison on this particular part, but I won't die if they can't. And I guess I won't be spending the $2300, either! Thanks for all the great feedback, guys!

The absolute best machine for high-precision/fine-finish 3D/mold making is the VM-series machine. As Pondo stated the chip-to-chip time on the SS is superior to non-SS machines, because of the higher rapids and fast tool-changes. If your machining for three hours with one tool change you will not realize the benefits of an SS. If you make one 3D part per year, you will not realize the benefits of a VM. The VF-2 and the VF-2SS, when HSM is turned on; perform nearly identical and almost as well as a VM.

extanker59: I would recommended the VM-2 for you, based on your last post. The VM may have a higher base price, but a VF-2 with all of the options a VM-2 has standard; would cost more.

[haastec]

[QUOTE=MarkSerbu;939379]Damn, I wish I'd known this BEFORE I bought my machine! [QUOTE]

Sadly, your sales rep should have helped you decide on the right machine for you and truly know the differences between them besides what is on the stickers. Instead, some just take your order and their commission. Want fries with that?

This is not to say you have a bad machine by any means; I am sure you will enjoy the new machine and that new cosmoline smell too!