Multi-Part Series: Greater Capability Means More Applications—Automated Drill Head Attachment for Piercing Fragile Laminates
One of the best features of abrasive waterjets is their ability to make intricate cuts in almost any material—from a thick piece of rugged tool steel to a thin piece of fragile composite or laminate. This gives a shop the flexibility to take on almost any cutting project and is one of the reasons why so many shops are now using abrasive waterjet cutting systems.
Many shops have found the market for cutting composites and laminates to be particularly attractive. Alternative cutting processes such as laser or plasma may be unsuitable because of heat considerations and because of the potential for producing toxic fumes. Wire EDM won’t work in non-conducting material. Routers and conventional machine tools are limited in their ability to cut complex parts and the dust produced by the cutting process can be a real environmental headache. Abrasive waterjets, on the other hand, can cut these materials quickly, cleanly and accurately with an excellent surface finish and no hazardous fumes or dust.
Some shops have found that the piercing process used to create a starting hole prior to abrasive waterjet cutting can create a challenge in those laminated and composite materials where the bonding agent is particularly weak or may have voids. Pressure at the tip of the abrasive jet stream as it pierces through the material can force water and abrasive into voids and between weakly bonded layers of laminate. This may cause “blistering” or laminate separation in the vicinity of the pierce point and ruin a part. Techniques used to pierce brittle material, such as gradual water pressure ramp-up and abrasive pre-loading through vacuum assist or flow timing, really can’t eliminate this problem if the laminate bond has weak areas or voids.
The OMAX Drill Head Attachment quickly and easily solves this challenge. It uses a computer-controlled mechanical drill to create a starting hole at each pierce location. This means that the abrasive waterjet has a material-free area to start each cut and so no potentially damaging pierce pressure occurs. The Drill Head Attachment mounts quickly and easily to the Y-axis carriage parallel with the Z-axis. Its function is automatically controlled by the OMAX Intelli-Max control software. The operator has the choice of either pre-drilling all of the pierce points in advance of cutting the entire part or pre-drilling each individual pierce point and then cutting that feature in sequence. The control software automatically moves the Drill Head to the exact location of each planned pierce and uses the reliable mechanical drilling process to assure blister-free starting locations for the abrasive waterjet.
As with all OMAX accessories, the Drill Head Attachment is fully retrofitable to any OMAX system. It provides the shop owner with expanded capabilities and thus an expanded market and more business. That means that more shops and manufacturers can improve their bottom line with the addition of an abrasive waterjet cutting system. Remember, our goal is an abrasive waterjet in every shop.
Best regards,
John Olsen
