Rotary Power-on Power-off

[tripper_11]

I have a Ryobi CG180SPK Grinder Sander Polisher. Have been using this for over a year now. Speed variable is 1-6:

Polishing 1-2 = 1500RPM
Sanding 3-4 = 3500RPM
Grinding 5-6 = 6500RPM

Yeah, it's a hybrid and very flexible machine. I've mastered the use of this specific rotary for quite sometime. In order to operate at the lower 600-800 or 800-1000 RPM (to apply wax) I just do a Power-on, Power-off technique.

I don't know if this true with all Rotaries, but as far as know, my Makit 9227c also has this characteristic: that before going to the maximum preset RPM, it speeds up to a certain period of time, as if like having a clutch disc inside that slowly hook with the rotary.

To understand, it goes like this: some rotaries go up automatically at the preset RPM in an instant or right after you press the trigger. But this clutching action i mentioned above does not do the same thing. The Rotary does not just speed up to the preset RPM but rather "accelerates" before reaching the preset RPM.

With this characteristic of my Ryobi and Makita, I am able to do Power-On, Power-Off technique for "waxing." It's like powering on (pressing the trigger) and powering off before the Rotary reach the maximum RPM. Since my preset RPM at speed setting 1-2 is 1500RPM, I'm able to power off before it reach 1500RPM (or at 800-1000) and then power on again if it goes down 300-500 RPM.

This I do on my Ryobi (the Makita can be preset to 800 lowest, but some Rotaries like Ryobi hybrid can only go trigger-lock at 1500).

Is there anyone practicing this Power-On Power-Off technique on Rotaries with 1500RPM minimum trigger-lock to apply LSP?

Will it ruin the gears inside the Rotary?

[Mike Phillips]

Re: Rotary Power-on Power-off

Originally posted by tripper_11
IIs there anyone practicing this Power-On Power-Off technique on Rotaries with 1500RPM minimum trigger-lock to apply LSP?

I know some people like to apply their LSP's with the rotary, but I personally and opt for either the dual action polisher or application by hand.

Will it ruin the gears inside the Rotary?

I don't know if it will ruin the gears of the rotary buffer, I don't know about the Ryobi, but the Makita is pretty stout tool. You might wear out the on/off trigger over time however.

Mike

[tripper_11]

Thanks for the quick reply Mike.

You know I got this idea of applying the LSP and cleaning the surface as well in just one job. I don't know if there's a truth on this. But this is the reason why I do apply LSP (like NXT) with cleaning ability by availing the rotary's power. (unlike just an orbital or polisher).

At any rate, we all have our own preferences.

However, I'll try my best to LSP by hand always (though it's really exhausting).

[Tim Lingor]

Hey,

Just to add to Mike's comments...

Most last step products are designed to be applied by hand, RO, as well as a DA, but not a rotary. A rotary will increase the heat/friction. As such, who knows what that will do to a formula that was designed to be applied by other means. The chemists create and design products to be applied in a certain manner for a reason.

Tim

[Chubs]

From working in the maintenance field I would be concerned about the power-on power-off technic. I own the Makita and I know what you are talking about. I'ts not a clutch it's the design of the motor. The motor has different windings in it for starting and different windings for running after start-up. The start windings are designed to start up slow to reduce torque and kicking of the buffer, along for other reasons. By turning on and off you might end up burning up your windings and destorying the motor.
IMPO, once you start it try to keep it going until your done polishing the section. I think it would be easier on you and the buffer.
I'm curious, does the buffer get hotter than normal when turning on and off repeatedly. If it does, does the cord even get warm. Because during start up you use the most current (or amps) to get the motor turning and that produces heat. And heat can cause failures.

Hope this helps,
Chubs

[Tim Lingor]

Hey Chubs,

Great post!! Thanks for the info!!!!

Tim

[gb387]

Originally posted by 2hotford
Hey Chubs,

Great post!! Thanks for the info!!!!

Tim

I agree! I understand how its done on a much larger/higher HP electric motors. But I have always wondered how that worked on a buffer. The Porter Cable Rotary does the same thing.

[tripper_11]

I employed that power on power off technique to spread the product first and to avoid splatter i.e. #83 or #80. After that I go max 1500 rpm. Yes, it gets hot even without the power on power off.

Anyway, tnx for that great info. Have been wondering for quite sometime. now I know!

[Chubs]

Your welcome guys. Glad I could help.
Yes, mine gets warm especially on those 85 deg days with high humidity and I'm going over the car three times trying to do some paint correction. Maybe next time I will hit it with my temp. gun to see how warm it gets.

Chubs