Griot’s Garage BOSS G15 vs BOSS G21

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What is the difference between the Griot's Garage Boss G15 and Boss G21?Griot’s Garage The BOSS G15 vs G21 – do you know the differences between these nearly identical polishers?

Don’t worry, you’re not the first person to wonder which one is the better choice and why. People have been struggling to decide between the 15mm and 21mm throw polishers since the Rupes LHR 15ES and 21ES days.

It’s easy to confuse the two when some retailers go so far as to use the same picture for advertising each polisher.

As with most things in life, the devil is in the details and then it comes down to how you plan to use the polisher.

Griot’s Garage The BOSS G15 vs G21: The Comparison

Griot’s Garage The Boss G15

Griot's Garage BG15 15 mm The BOSS...
9 Reviews
Griot's Garage BG15 15 mm The BOSS...
  • Achieve fast results with a 15mm long-throw orbit and...
  • Stay comfortable with extensive energy dampening, double...
  • Instant start, variable trigger throttle and adjustable...
  • Has premium NSK bearings throughout with a machined CNC'd...
  • Brush ports enable quick and easy brush changes. Max 5000...
  • Type: Orbital
  • Forced Rotation: No
  • Power Type: Electric
  • Throw (mm.): 15mm
  • Throw: Long
  • Min Speed: 0
  • Max Speed: 5000
  • Soft Start: Yes
  • Trigger Lock: Yes
  • Power (watts): 900
  • Weight (lbs.): 8.8
  • Backing Plate (in.): 5″
  • Cord (ft.): 13′
  • Warranty: Lifetime
  • Replacement Brushes? Yes

Griot’s Garage The Boss G21

Griot's Garage BG21 21 mm The BOSS...
16 Reviews
Griot's Garage BG21 21 mm The BOSS...
  • Achieve fast results with a 21mm long-throw orbit and...
  • Stay comfortable with extensive energy dampening, double...
  • Instant start, variable trigger throttle and adjustable...
  • Has premium NSK bearings throughout with a machined CNC'd...
  • Brush ports enable quick and easy brush changes
  • Type: Orbital
  • Forced Rotation: No
  • Power Type: Electric
  • Throw (mm.): 21mm
  • Throw: Long
  • Min Speed: 0
  • Max Speed: 5000
  • Soft Start: Yes
  • Trigger Lock: Yes
  • Power (watts): 900
  • Weight (lbs.): 9.1
  • Backing Plate (in.): 6″
  • Cord (ft.): 13′
  • Warranty: Lifetime
  • Replacement Brushes? Yes

As you can see, they both have the same motor, body, and weight.

The motor on both is rated at 900 watts with a min speed of 0 orbits per minute and a max of 5000 OPM.

The body is the same with both having the rounded forward hand hold, double shot rubber grips, pistol grip, trigger, and trigger lock.

The weight is also similar for both models.

Griot’s Garage The BOSS G15 vs G21: The Differences

Not a lot of physical differences in the product specs huh? To sum them up:

  • The Griot’s G15 comes with a 15mm throw (also known as a spindle orbit) and a 5″ backing plate for running 5.25″ and larger pads.
  • The Griot’s G21 comes with a 21mm throw and a 6″ backing plate for running 6.25″ and larger pads.

So what does that translate to as far as real world usage?

The longer 21 mm throw on the BOSS G21 allows the pad to cover more area with each orbit. It also increases the leverage the motor has on the pad when it’s whipping it around in circles allowing for more powerful polishing of flat surfaces.

The larger backing plate on the BOSS G21 allows for running larger pads, again to benefit covering more area in less time. Though Griot’s Garage does permit (and even promote) switching between the 6″ and 5″ backing plates on each tool. They actually designed this ability into the tool by fabricating the counter balance to be accommodating to both sizes of backing plates and accompanying pads.

In general, with orbital polishers, the smaller the pad the more nimble the tool is and the more aggressive the correction of that pad is. So putting a 5″ backing plate on the G21 would increase its aggressiveness a bit. Conversely, putting a 6″ backing plate on the G15 would reduce the polisher’s aggressiveness slightly.

It’s not all sunshine and roses though. The longer throw of the G21 also makes the machine more susceptible to stalling out (stopping the pad from spinning) on tightly curved and angled surfaces.

Combined with the larger pad the polisher has a harder time polishing smaller areas too.

This is where the G15 comes in. As you’ve probably deduced the G15 with it’s 15mm throw and 5″ backing plate gives up a little pad power and area of coverage for more versatility in smaller and more curved / angular areas.

Is the Griot’s Garage The Boss G15 right for you?

Choose the Griot’s BOSS G15 if:

  • You have a budget of less than $365
  • You will be primarily polishing smaller vehicles or vehicles with lots of curves and angles.
  • You only plan to own one polisher and will need a tool that can almost do it all.

Is the Griot’s Garage The Boss G21 right for you?

Choose the Griot’s BOSS G21 if:

  • You have a budget of more than $365
  • You will be primarily polishing larger vehicles without many angles or curves like trucks, boats, and RVs.
  • You plan to own multiple polishers or already have a smaller polisher that you can use for more intricate detail work on smaller panels and in smaller places.
  • You’re a professional and time is literally money.

It’s easy to overthink it but it really is as simple as that. My honest opinion is that when in doubt, buy the The BOSS G15.

The BOSS (Best of Show System) Explained

Regardless of which polisher you choose, understand that these are part of a carefully thought out system that includes pads and polishes designed to work in concert with the machines. While you can run any pad and any polish you want with great results you’ll get the best and most fool proof experience using the pads and polishes that are also part of the BOSS system.

As a bonus, you can usually find the BOSS pads and polishes sold with the polisher in kits for less than the cost of buying the polisher by itself with other companies pads and polishes so I encourage you to look for that.

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