What should be used to cut and machine glass based phenolics?

In many cases, the same machining operations employed in the fabrication of metals and woods may also be adapted to glass-based phenolic grades. However, certain slight changes in tools and use of proper speeds are necessary.
Diamond or tungsten-carbide tools will give more satisfactory work with longer, more economical life than high-speed tools.

Circular Sawing

A diamond-impregnated wheel with copper body 1/16" thick and 12" diameter run at 3,000-6,000 RPM will give good results cutting dry with a good exhaust system. The material is fed by hand into the saw as fast as it will cut without forcing the saw. Idling creates friction and heat, which causes excessive drilling and burning. A flood of water on the work and wheel can be used when necessary to prevent overheating. Abrasive wheel cutting underwater is also recommended.

Band Saw

For best results, carbide-tipped blades should be used. Work should be fed lightly, and the blade should be kept sharp. Sawing can be done dry with a good exhaust system.

Shearing

Thickness up to 3/32" can be sheared. The same standard practices are used for other laminated plastics.

Turning

Conventional machining, such as turning, boring, and facing, can be done on automatic screw machines, standard and production lathes, and hand turret lathes.

Carbide-tipped tools and cutters should be used with surface speeds below those used for paper-based laminates. Tolls should be ground with a zero rake, and machining can be done dry with an exhaust system to remove dust. A coolant can be used but is not necessary.

Milling

Glass base laminates can be milled satisfactorily on any conventional metal-working machine. Carbide-tipped tools should be used. Only climb or down milling should be practiced as an up system to remove dust. A coolant can be used but is not necessary.

Drilling and Tapping

When drilling glass-based grades, a carbide drill should be used. The materials can be drilled dry with a good exhaust system to remove dust. A flood of water on the work and drill can be used when necessary to prevent overheating and dulling of drills. High-speed drills, nitrate treated, can be used but must be sharpened more often. Care should be taken when sharpening that the drill is cut back far enough to the original body diameter of the drill. The spindle speed for these grades is 4800 RPM for ¼" diameter drills.

The methods for tapping these materials are much the same as for tapping paper base laminate plastics. The abrasiveness may cause taps to cut very close to size, resulting in a tendency toward binding when backing out. Standard high-speed steel taps can be used on short runs. For any sizable quantity, carbide taps should be used. Taps should be purchased oversized. Coolant can be used but is not necessary if a good exhaust system is available.

Threading

External and internal threads can be cut on a lathe with a carbide-tipped tool and dry. Fine cuts should be taken to give the best results. A coolant can be used, but it is not necessary.

Buffing

Standard polishing rouge on a rag wheel gives satisfactory results for phenolic requiring a polished surface.

Grinding and sanding may be done by belt, disc, or centerless methods. No lubrication is necessary.

Stamping and Engraving

Phenolic surfaces to be stamped should be smooth. Sanding may be necessary, in some cases, to obtain satisfactory results. Compression presses employing heated dies give the best results.

Engraving can be done with any standard engraving machine. Tools should be sharp to produce clean-cut edges.