22 November 2010

50 Years of Service - Is it Time to Retire?

For over 50 years Criterion Machine Works has produced the DBL series of boring heads. These boring heads were designed for manual milling machines that predominately used R-8 shanks. The mounting end was chamfered to match the spindle diameter of the R-8 shank. 

DBL-202B Boring Head
Designed for Manual Milling Machines

In its day this was one of the most popular boring heads available. It offered the user a large range from .250” to 6.687” in diameter. The .001” on diameter dial adjustment was equal or more precise than other models available at the time. It was not uncommon for machine shops to be started with the purchase of a Bridgeport Mill, a set of R-8 collets, a Kurt vise and a Criterion DBL boring head.

CB-202B Boring Head
Designed for CNC Machining Centers

As CNC machining centers grew in popularity, we introduced our CB Style Boring Head. The CB series boring heads were designed with a larger mounting face to be compatible with the tool holders used on CNC machines. The larger mounting surface also gives a more rigid and stable connection for performing a boring operation. All the ranges and adjustability features of the various DBL models were maintained in the CB design.

The CB style boring heads will perform equally as well as the DBL style in a manual milling machining operations. Unfortunately, the same is not true of the DBL style the smaller mounting surface is a disadvantage in CNC machining center operations.