RIDGID R8646K 18V Cordless Reciprocating Saw Kit with 4.0 Ah Battery and Charger review

RIDGID 18V reciprocating saw · R8646K 4.0 Ah kit

The R8646K is the kit version of RIDGID’s brushed 18V reciprocating saw. The exact U.S. kit page names the R8646B saw, one R87004 4.0 Ah lithium-ion battery, one R86093 18V charger, a wood-cutting blade and the operator’s manual. That package is materially different from R8646B tool-only even though both use the same documented saw body. This assessment follows the exact package page and the R8646 manual; it does not claim hands-on use or measured cutting performance.

Same saw body, a different starting package

RIDGID lists a 1-1/8-inch stroke and 3,000 strokes per minute for the saw. The manual gives the no-load range as 0–3,000/min and describes a variable-speed trigger, so speed changes with trigger pressure. The product page identifies a brushed motor. These figures and features describe the mechanism; they do not quantify work per charge, cutting rate or a maximum material size. The sources reviewed do not provide a named cut-capacity table or an independent comparison against another saw.

The K suffix matters because it carries the separately identified battery and charger. The manufacturer’s “Includes” list names the R8646B saw, R87004 battery and R86093 charger, while the product description also lists the wood blade and manual. A 4.0 Ah rating identifies battery capacity, not a guaranteed runtime: material, blade selection, pressure, temperature and the condition of the pack all affect how long a job takes. Buyers with compatible RIDGID 18V batteries may find the tool-only R8646B package a more relevant comparison; buyers who need the listed power components can compare the R8646K. The exact numbers on the carton should agree with the offer.

Control features are in the common R8646 manual

The manual explains that the trigger varies speed and that the shoe pivots up and down in both directions. It also describes the lever-operated, tool-free blade clamp. Before changing a blade, remove the battery, raise the clamp lever, insert the blade fully and release the lever to secure it. The blade can be installed with its teeth facing either direction. These are practical setup features, but neither a tool-free clamp nor a pivoting shoe removes the need to stabilize the workpiece and keep the shoe bearing against it during a cut.

The box’s included blade is for wood. The manual’s blade guidance distinguishes material: it gives 10 TPI as typical for wood, recommends 14 TPI for plastic and soft metals, and 18 TPI for hard metals. For metal cutting, it advises a slower speed, light pressure, a purpose-made blade and cutting oil for steel and soft metals. It also calls for clamping the work close to the cut to control vibration. These details make the kit a starting point rather than a ready assortment for every demolition task; check whether you need additional blades for your planned material.

Work within the documented handling limits

For ordinary cutting, the manual says to bring the blade to speed before contacting the workpiece, secure the material with a vise or clamps, hold the saw firmly and avoid forcing it. It warns to check for hidden electrical wiring, water pipes and mechanical hazards when cutting into a wall. For plunge cuts in wood or wallboard, the manual specifies an interior starting point with the shoe’s front edge held firmly against the material and warns that blades longer than six inches should not be used for plunge cutting because they can whip. If a cut cannot be supported safely or its path is uncertain, stop and reassess rather than relying on the saw’s shape to make it safe.

The product photograph shows the saw with a battery and charger, but it is not an inventory of every package item. The written SKU list is the better evidence for contents. It does not list a case; I would confirm any seller-added case or extra blades separately instead of assuming they accompany every R8646K offer.

Weight and feature gaps are real buying checks

The page publishes “Product Weight” as 5 lb without defining whether that means the saw alone, a battery-equipped tool or another catalog basis. The included 4.0 Ah pack does not clarify the weight field, so this assessment leaves bare-tool weight unknown rather than counting the R8646K under a strict five-pound tool limit. The page and manual also do not establish a named cutting capacity, selectable orbital mode, vibration-control system or dimensioned body profile. These are unknowns in the reviewed evidence—not proof that an unlisted feature is absent.

Who should choose the kit rather than the bare tool

R8646K is the package to investigate if the same conventional two-handed R8646 saw and an identified 4.0 Ah battery plus charger are wanted together. Its strongest contrast with R8646B is package completeness, not a different motor or cutting mechanism. If you already own a compatible pack and charger, the B version avoids duplicating those items; if you need them, verify R87004, R86093 and the R8646K suffix on the actual offer. Also check current registration conditions for the manufacturer’s service agreement, select a blade for the material and seek a defined weight basis if mass is a hard constraint.