SAW DOCTOR report

Question: Can I cut a mix of aluminum and steel(s) on one machine?

The simple answer is yes, with the following caveat: whereas you can cut aluminum on a machine designed to cut steel – obviously not as fast, but with very acceptable results – you must not attempt to cut steel on an aluminum machine: dangerous.

Depending on the application, steel sawing machines with HHS blades run at peripheral blade speeds of 40 to 240 FPM = the speed of the tooth through the cut. On machines designed specifically to cut aluminum the peripheral blade speed is in the 14,000 FPM range, running carbide-tipped blades.  Aluminum is far softer than steel, and therefore the cutting forces – and the heat produced – are much lower than when cutting steel. Kaltenbach steel machines run through a gearbox for maximum torque at lower blade speeds, whereas our aluminum machines employ a much stronger main motor driving the blade via a multi-belt pulley system, to achieve the very high peripheral blade speed required. The steel machines incorporate fully hydraulic blade feed and clamping, to deal with the high cutting forces, whereas the aluminum models feature pneumatic clamping for speed, and air-over-oil blade feed (for constant feed rates, even on large solids).

If aluminum cutting makes up only a small percentage of your overall application, then just cut at the feed rate as you would for steel, but use the fastest blade speed available, and use the same blade(s).  However, if the split between steel and aluminum (and possibly other bright metals, such as brass and copper) is more even, then it would make sense to keep separate blade inventories, and add an atomizer lubrication system for the non-ferrous materials.  Running the same blades long term on a variety of metals will result in “pick-up” on the blade flanks, which not only ruins surface finish, but also increases drag (and therefore heat), which shortens blade life.  Using an atomizer lubrication system when cutting aluminum and other bright metals will prevent pick-up, improve surface finish and extend blade life … all of which reduces cost per cut. Keeping separate blade inventories also allows a more flexible selection of pitch and tooth geometry to suit the different material characteristics, further increasing efficiency.

Dos and Don’ts:

• Do cut aluminum on a steel machine
• If possible batch materials and run different blades for steel and aluminum
• If aluminum is a large percentage of the job, fit an atomizer lubrication system**
• Run the highest available blade speed when cutting aluminum
• Do not under any circumstances cut steel on an aluminum machine

** coolant/lubricant selection to be covered in a future SAW DOCTOR report

      FOR FURTHER INFORMATION CONTACT DAVE McCORRY at 1-800-TALK-SAW x 16