Why I Chose the 15 Over The 21?

[Zubair]

Seeing as this gets asked alot, thought I would air my views and personal experience from another post where I previously stated this.

Why I purchased the 15 over the 21 was:

1:Smoothness, claimed to be the smoothest single head DA in the world and I truly believe that claim.
2:Ability to stall less on curves over the 21,naturally as a result of the shorter stroke.
3:Can fit into tighter spots with the shorter stroke over the 21.
4:Less aggressive on pads than the 21 makes it more economical long term.
5:Suited and designed for the 5" backing plate and 6" pads without compromising smoothness and machines longevity.
6:Rupes 21 designed for bodyshops and large flat panels. Rupes 15 designed for the Detailer and even says so on the polisher. Every car I've detailed has curves opposed to vast areas of flat panels.
7:Throw/Stroke length is just perfect for almost all needs and requirements.

[FUNX650]

2:Ability to stall less on curves over the 21,naturally as a result of the shorter stroke.

I thought that it was because:
When the Rupes BF-polishers' strokes gets shorter
(ex.: 21mm-->15mm--->12mm)...that Rupes has
designed their motors to then: spin faster, in order
to maintain polishing power.


And...I wasn't aware that the 21 had such a
propensity to stall on curves/curved panels...
more so, that is, than the 15.


Bob

[WRAPT C5Z06]

Did you go with a Rupes?

The Rupes LHR15 is a dud, IMO. LHR21 definitely felt more powerful. Even though they have the same motor, the momentum alone from the larger throw makes a difference.

The motor efficiency is supposed to be much better with the new Mark II series.

[Zubair]

Those that bought or are inclined toward 21's will ofcourse feel otherwise ;-)

[KMG]

Did you go with a Rupes?

The Rupes LHR15 is a dud, IMO. LHR21 definitely felt more powerful. Even though they have the same motor, the momentum alone from the larger throw makes a difference.

The motor efficiency is supposed to be much better with the new Mark II series.

You are clearly misinformed with what you are stating. The 15 actually has a higher RPM level then the 21. I have both a 21 and a 15 and actually find myself using the 15 more then the 21. The 21 is great for larger flat panels, however in most cases the 15 simply works better with the contours of many cars where the 21 will stall out. Obviously if you can afford to have both, they both have their place where they work great. But if I could only have one I would take the 15 over the 21 any day.

[Zubair]

I've used the Mini, Duetto,15 and 21 and the 15 is the best all rounder. I haven't encountered any situation where the 21 outcut it but I have encountered plenty situations where the 21 could not fit or would stall far too frequently where the 15 outshone it. Its been designed for detailers and it shows. Theres a reason why the new Flex is 15mm and not 21 too. 15 is the sweet spot, most smooth most balanced.

[KS_Detailing]

prefer my 15 over my 21 as well

[jms493]

I choose a Boss 15 due to the fact that I dont have large panel vehicles and this is a hobby. Occasionally I branch out and due some details for friends or references but few and far between. The 21 would be difficult to use on the cars I have and will have. If I had a large SUV or a full size pickup I may have opted for the 21.

[EzyBrzy]

Makes it reassuring that I chose the Boss 15:xyxthumbs:

[mrbtd]

Have you used both the 15 and 21 ?

[jms493]

I have not used the 21.

My next polisher I would like is the FLEX PE8 Kompakt Rotary Polisher. Looks great for front and rear bumpers.

Maybe next black friday.

[Rsurfer]

I have not used the 21.

My next polisher I would like is the FLEX PE8 Kompakt Rotary Polisher. Looks great for front and rear bumpers.

Maybe next black friday.

Be careful using a rotary on plastics. You would be safer using a DA like the Rupes Mini.:props:

[jms493]

Be careful using a rotary on plastics. You would be safer using a DA like the Rupes Mini.:props:

hmm....let me look. Thanks.

[Justin at Final Inspection]

G21 user here. No problems so far. I have it equipped with the 5in BP and seems to work just fine. Very rarely will I use just one machine on a car.

On bumpers and tight areas I use my Flex PE8 Kompakt.

[WRAPT C5Z06]

You are clearly misinformed with what you are stating. The 15 actually has a higher RPM level then the 21. I have both a 21 and a 15 and actually find myself using the 15 more then the 21.

I'm not misinformed. They both use 500 watt motors. Just because the RPM range of the 15 is higher, it does not make it more powerful; obviously. With a 5" BP on the 21, you should be able to do mostly what you could do with a 21.