“The Eurotech lathe gave us huge advantages over the Swiss machines. For instance, the work envelope is safer and easier to work in and offers much better chip control. The horsepower and rigidity make the Eurotech a much more powerful machine and gives you double tool life. The guide bushing support is terrific; we get no blend lines and machine a perfect part in one operation!”
“With the Eurotech lot control is not a problem and running unattended over the weekend is simple. The Eurotechs are simple to operate and hold their resale value better than any other machine out there.”
1. Work envelope – Ease of Setup. It’s all about safety! Swiss are flexible but to work on them is a nightmare. Every time you work on it you’re getting cut up, banged up; oil drips down on your cuts, etc. It is hygienically a huge problem. You want room in the machine to work in, so the work envelope space of the machine is very important to the guys on the shop floor. Swiss do not give you much room to work in.
2. Work envelope -Chip Control. This is a major problem on Swiss machines. Yes, you can turn the part but where do the chips go? They wrap up on next tool right beside it. They fall halfway down in the chip tank. The next tool picks them up. For parts that are square or rectangular and you’re taking huge volumes of material off, (especially with materials such as nickel alloys, aluminum and copper), you can’t break the chip up and high pressure coolant is not always effective at pushing the chip from the tool. You need good chip flow as well as a decent cycle time but with the small work envelope of the Swiss it’s a huge headache. The Star SR32 has 8 cubic feet inside the machine; the Eurotech Rapido has work space of 22 cubic feet inside machine. That’s almost three times more volume for tool changes, chip control, and coolant flow and everything else that goes with it. Not an issue on the Eurotech Rapido.
3. Horsepower and Rigidity. For high metal removal rates, Swiss machines often do not have the power needed to get the job done efficiently. Combined power on the Star SR32 is 8.9 kilowatts. The Eurotech Rapido has 24 kilowatts of power. This is a BIG difference. With horsepower comes rigidity. We ran the same parts on Swiss and the Eurotech Rapido and found that the Eurotech Rapido had double tool life simply because of the larger tool holder. Vibration wasn’t transmitting from the work piece to the tool holder.
4. Guide Bushing Support – part example – muzzle break with 150 holes in it. Star SR20 has ¾ of an inch of bearing surface on the guide bushing so once you machine ¾ of an inch you can never machine more than that and then go back. We try never to do any secondary or off line deburring. So once you’ve machined it, it’s going to drop out of the support of the guide bushing. You’d have to break this part up into thirds which gives you blend lines – it’s impossible to get a perfect blend between those two rough and finish passes. We want to make our parts look like a diamond – perfect. We don’t want the blend lines but they are unavoidable on Swiss. Not an issue on the Eurotech Rapido.
5. Bar Stock Quality. With a Swiss a lot of companies like to run ground stock but it’s not optimal. (Grind lines on ground stock are perpendicular to your axis of force so grind lines are going around a bar, while you’re trying to push against the grind lines). Swiss do not require ground stock; however, without it, we have to hold an OD tolerance of +/-0.0003” within material lot. Having to retension a guide-bushing between different lots of the same material is a huge waste of time. Long unattended runs over a weekend are not possible on Swiss machines unless sufficient material from one lot is available. With Eurotech lot control is not required, as in a brass part, we can load up the Rapido with mixed lots of material and run for 48 hours unattended as the size variations from the different material lots is compensated for by the collet where the guide-bushing of a Swiss machine would prevent this.
6. Chucking and Manual Operations. We try to service customers as best as we can and sometimes that requires small runs of manual parts or modifying existing parts. We don’t have manual equipment. Locating the part in the sub-spindle of a Swiss because it is not long enough for the guide-bushing support causes many issues in maintaining length and positional tolerances. While we really hate to stop the efficiency of working off a bar to hand load a Rapido, occasionally, it is necessary, easy, and meets a customer’s critical need.
7. Resale Value is much better with Eurotech than Swiss. Any machine purchase for a job shop has risk. You never know what job you’re going to have month to month, day to day. The risk is much less with conventional CNC’s, especially Eurotech as they hold their value longer than any machine I’ve ever seen.
8. Operator Capability – you need a “contemplative operator” for Swiss. Machining a complex part on Swiss is like playing chess. You have to be thinking many moves ahead and a crash is just a brief distraction away. Conventional is much simpler and it’s far, far easier to train a new operator on Eurotech than Swiss.
9. Transition Point – The defining point for parts to be run on Swiss or conventional is .687 (11/16). From 11/16 and over it is almost always far better to run on the Eurotech Rapido.