Machine-Setup

A deep hole drilling machine is a significant capital investment — often $200,000 to $1 million depending on size and capability. The acceptance test is your only opportunity to verify the machine meets specifications before you are committed to it. I have been involved in several machine acceptance tests. Here is the procedure I use. Documentation Review Before any physical testing, I review the documentation: Machine specifications vs purchase order — confirm all options and features are present Electrical and hydraulic schematics Operator and maintenance manuals Spindle runout certificate from the manufacturer Coolant pump performance curve Alignment certificate from the manufacturer If any documentation is missing, I note it on the acceptance report. Missing manuals will cause problems later. ...

I have seen shops spend weeks chasing straightness problems when the root cause was a spindle that was 0.03mm out of alignment with the bushing. Checking alignment takes thirty minutes with a test bar and a dial indicator. Here is the procedure I use. What I Check and In What Order I check alignment in a specific sequence because each step depends on the one before it: Spindle condition (runout at the taper) Spindle axis parallel to the way axis Bushing holder concentricity with spindle Bushing ID concentricity with spindle Workpiece axis alignment with spindle If I skip a step, I waste time chasing a problem that does not exist. ...

Large BTA drilling machines weigh 15 to 30 tons and generate significant cutting forces during operation. The foundation must support this weight and absorb the vibration from high-thrust drilling. I have been involved in installing several BTA machines, and I have seen the consequences of poor foundation preparation. A foundation that is not done right causes alignment problems that affect every single hole drilled on that machine. Foundation Design Specifications The foundation should be a reinforced concrete slab that is structurally separate from the building floor. I recommend a minimum slab thickness based on the machine weight and the soil conditions at the installation site. ...

I use a fixed setup checklist for every deep hole drilling job. It takes five minutes to run through and has prevented more scrapped parts than any other process control I have implemented. A cold machine, a dirty bushing, or a clogged coolant line will ruin a part faster than any programming mistake. Step 1: Machine Warm-Up I run the spindle at operating speed with coolant circulating for at least 30 minutes before starting a job. A cold machine does not drill straight holes because the spindle, headstock, and bed expand as they warm up. ...

Installing a deep hole drilling machine is more involved than most other machine tools. The long stroke and high cutting forces require a solid foundation and careful alignment. I’ve been involved in installing several deep hole drilling machines. Getting the foundation and alignment right from the start prevents problems that would otherwise show up in every hole drilled. Foundation Requirements A deep hole drilling machine needs a foundation that absorbs the cutting forces and prevents vibration. The foundation requirements depend on the machine size and weight. ...