cycle times

Cycle Time Study - Hurco Ultimotion

One of the huge advantages of a Hurco is the architecture used in the control system. Not just the fact that the control is a full PC, but the way it is integrated into the control hardware. The servo’s, drive’s, amplifiers and all the components that make up the “motion control” are what would be called the “architecture.” On a Hurco it results in faster cycle times by around 30%. They print that directly into the brochures and on the quotes. They stand by it. I usually guarantee 20% knowing that I will beat it. Even though it is something well documented with plenty of YouTube videos to back it up, its hard to understand how. If its the same g-code on both machines and you do not change anything, use the same tools, how is it faster?

I was delighted with the chance to put the numbers to the test when the head of Hurco Engineering approached Gage Machine Tool with a cycle time study. They needed a customer with a new Haas VF2 to run a specific set of programs with no alterations for a comparison to a Hurco. I happened to have a customer close by that had a new Haas VF2SS and figured that would be a perfect fit. You can see a below what the part program looks like out of Hypermill. Hurco Germany had been tasked with making a set of programs for machining the sample part. The study was actually being done for a large potential customer in India. (programs are in metric)

hypermill program image.jpg

The way that Ultimotion works on the Hurco can be thought of as driving a sports car down a country road. The road curves up and down and around hills and you can only see so far ahead. You wish you could take the road at the posted limit of 60 MPH but you have to slow down for the curves otherwise your off the road and into a ditch. This is the way motion control works on every g-code CNC on the planet. Its called block look ahead. The control can only see so far in front of it and has to react as quickly as possible for the curves. The Hurco however has “infinite” block look ahead. Before the first tool is even cutting the control has read the entire program and knows the track better than Dale Earnhardt. On a g-code machine it has to slow down just a touch to make that curve, this does not happen on a Hurco. The graphic below shows how Ultimotion improves on a standard move from one location to another and can hit full rapids with a slight arc move. The graphic is drawn to exaggerate the arc and show how it is above the retract plane. There are simply fewer times that the machine has to stop and start. (6 versus 3)

Ultimotion Drilling Cycle Graphic.jpg

This becomes obvious when you look at the differences in cycle time below as compared on the Haas VF2SS and a Hurco VMX24.

Program 1 (21% reduction)

Haas: 49 min 59 sec
Hurco: 39 min 27 sec

Program 2 (7% reduction)

Haas: 1 min 35 sec
Hurco: 1 min 28 sec

Program 3 (39% reduction)

Haas: 41 min 41 sec
Hurco: 25 min 33 sec

Program 4
Was not needed

Program 5 (49% reduction)

Haas: 1 hour 14 min 59 sec
Hurco: 38 min 15 sec

Program 6 (40% reduction)

Haas: 2 hours 1 min 7 sec
Hurco: 1 hour 12 min 28 sec

The more complicated the geometry and the longer the cycle time is has some impact but that is not the whole story. By a percentage it would be better to look at it as a curve where you almost reach 50% reduction in cycle time. The geometry itself plays a role in how much time you save. If you think back to that country road it starts to make since.

A simple part that has a 3 minute cycle time on a g-code machine would see a small reduction in time on the Hurco, perhaps down to 2 minutes and 30 seconds. Maybe that’s trivial for a 5 part run? True, I’ll give you that. But if you can save say 15 seconds of run time or more on every single part you run for the whole year with out any effort on your part, what’s that add up to? Let’s look at some numbers since we are all numbers guys really.

15 seconds   X   1000 parts  =  15000 seconds  = 250 minutes  =  4.17 hours

I know you run more that 1000 parts a year on one machine but I’m being conservative. If we run the numbers again with something more like what a typical job shop run they would look like this;

6.5 hours of up time on a CNC Mill per day
5 minute average cycle time (IF this sounds slow or fast for your parts then change it)
78 parts per day
220 days of operation per year
17,160 parts in a year.

So that sounds high? How about we cut that in half for the sake of the argument. I don’t know about you but if my machine was only running 3.25 hours a day I would fire someone (and I have).

So that puts us at 8,580 parts a year off the machine.

If we stick to the 20% faster cycle time that’s a whole minute saved. On a Hurco it would be 4 minutes instead of 5 minutes. Run the equation again;

60 seconds   X   8,580 parts  =  514,800 seconds  = 8,580 minutes  =  143 hours

If you shop rate is 80/hr (seems kinda low) then you just saved $11,440 worth of production costs on all your parts. Even if you are just running the machine 3.25 hours a day. You can do the math and figure out how much you save if you run your machines all day across two shifts, three.

If you want a personal demonstration of how this works you can download the g-code program yourself and run it on your machine. See the cycle time you get and then come look at it on a Hurco. You can do that at one of our showrooms or at one of our customers. Just give a call or send us an email.