Checklist for a Well-Tooled Shop

By Kip Hanson

Part of Machining For Dummies Cheat Sheet

Good toolholders, workholding, and accessories are just as important as good machinery, but many shops invest heavily in their CNC machine tools only to skimp on the tooling. Doing so means losing out on the benefits of new technology and not taking full advantage of your machine potential.

  • Setup time is a killer and quick-change tooling is one of the best ways to avoid it. This begins with an organized approach to workholding, using zero-point or ball-lock clamping systems, or a quick-change chuck on a lathe.
  • Quick-change toolholders are also important, especially on CNC lathes, where easily five minutes per turret position can be spent changing tools. Quick-change holders turn minutes into seconds.
  • Another way to reduce setup time and in-process disruption due to tool replacement is with offline presetting. Break out your crystal ball and be sure to purchase a system that addresses future needs as well as the current ones.
  • Shrink-fit tooling is one of the best ways to hold solid carbide drills and end mills.
  • Hydraulic toolholders and mechanical milling chucks are a good alternative to shrink fit, but are somewhat less “balanceable” than shrink fit.
  • Did someone mention balance? Balanced toolholders aren’t just for high-speed machining. In fact, most industry experts suggest spindle speeds greater than 8,000 rpm require balancing the entire toolholder assembly.
  • Never buy bargain toolholders, and always go for the best retention knobs you can find.
  • If the majority of your turned parts are under a couple inches in diameter and can fit through the lathe spindle, invest in a bar feeder. If you routinely have thousands of these parts to make, invest in a magazine-style bar feeder.
  • Robots are good for lots more than deep space navigation on starships. They’re also great at loading and unloading parts from machine tools.
  • As with a bar-fed lathe, a palletized machining center suffers less downtime and is far more flexible than the traditional, “two-vises bolted to the table” approach taken in many shops.
  • The next time your tooling rep buddy drops in with some carbide inserts or a new toolholder for you to try, consider how these additions will fit into your overall tooling strategy. Standardization is key to a manageable tool crib.
  • Don’t have a tool crib? Better set one up. Tooling is expensive and downtime even more so, and without an establish tool crib and tooling policy, you’re wasting money.
  • Now that your tool crib is in place, it’s time for a maintenance plan. Tooling should be routinely disassembled, cleaned, and checked for wear.