6852-20 – GAUGE SHEER

Milwaukee 18 gauge shear for cutting sheet metal and ductwork, driven by a 6.8 amp motor with variable speed to 2,500 strokes per minute. Note that Milwaukee lists this catalog number as no longer available, so stock is limited to what is on hand.

Specifications published by the manufacturer. Source: manufacturer documentation.

Specs

• ManufacturerMilwaukee Tool
• Motor6.8 Amp
• Stroke speed0-2,500 SPM (variable speed)
• Cutting capacity18 gauge
• StatusDiscontinued by Milwaukee

Do I need new gauges for R-454B?

Yes for anything the refrigerant touches. R-454B and R-32 are A2Ls, and the equipment makers' own service literature is blunt about it - all service equipment must be A2L rated, and non-rated gear is not to be used. That means an A2L rated manifold and hose set, a non-sparking recovery machine and vacuum pump, a sealed sniffer-style leak detector, and a recovery cylinder labeled for that refrigerant with left-hand threads. Your wrenches and nut drivers are fine. R-410A is the legacy generation now, and a 410A-only manifold does not carry you forward.

Can I charge accurately off analog gauges?

Read trends with them, not targets. A 0 to 500 psi analog face gives you maybe 5 psi of resolution, and at a saturation point 5 psi can be two degrees of subcooling. Use analog to watch a system move - a pump down, a defrost, a suspected restriction. Use a digital gauge or a probe set for weighing in and for superheat and subcooling numbers you intend to act on.

Why can I not just watch the compound gauge for vacuum?

Because it cannot see the range that matters. Full vacuum is 29.92 inches of mercury, and one inch of mercury is roughly 25,400 microns. A needle parked on 29.9 could be at 500 microns or 20,000. A micron gauge is not optional equipment on an evacuation, it is the only instrument that reads the number you are being held to.

What is a passing evacuation?

Pull to 500 microns with the gauge at the system, valve off the pump, and watch the decay. A rise that keeps climbing is a leak. A rise that levels off around 1000 to 1500 is moisture still boiling. Holding under 500 isolated is the pass, not a stopwatch.