Rotary VS Dual Action for Compounding

[Calendyr]

I have a rotary and pretty much never use it. It's in my arsenal just in case I can't do what I need with the DA.

Right now, if you use either a long throw DA like the Rupes 21 or a Forced Rotation DA like the Flex 3401, and you use a microfiber cutting disk with D300 compound, it is very close to what a rotary with wool can do. But it is safer. The one downside is that the microfiber cutting disk wear out really fast. I have not been able to do more than 4 cars with one. Also D300 is very expensive compared to other compounds. So there is a higher cost to the safety.

I have nothing against Rotaries, but for me, I really don't see a reason to take the risk of burning an edge to save what... 30 minutes out of the entire buffing process?

But in the end, I think you should use what you are most comfortable with. If you like using the rotary for paint correcting, then using the DA for polishing, then do that. It's probably the fastest way to go about it if you do a 2 or 3 step correction. In my world 1 step is king. People with daily drivers are usually not interested in having a 2 day correction done.

[Ronin47]

21 MKII cuts more than PE-14 and LH19E. Its the fastest tool I own. All tools can get the job done and with the abrasives and pads we have available a rotary is no longer faster.

[Joel1979]

https://www.instagram.com/p/BT-HDo0DjJa/

I have done many tests rotary vs wool and here is one

[jslym777]

You need to be more specific as to what kind of d/a, and to how It's set up.

You talking random orbital (what orbit stroke?) or forced? You talking microfiber / wool pads and heavy cut compound? New, modern compounds, or old technology.

Give specifics.

It comes off like you already know your answer and are looking for a fight.

I said using any combination, as long as were comparing apples to apples for the heavy compounding step.
Any DA, Rupes, Flex, Griots

[jslym777]

I have a rotary and pretty much never use it. It's in my arsenal just in case I can't do what I need with the DA.

Right now, if you use either a long throw DA like the Rupes 21 or a Forced Rotation DA like the Flex 3401, and you use a microfiber cutting disk with D300 compound, it is very close to what a rotary with wool can do. But it is safer. The one downside is that the microfiber cutting disk wear out really fast. I have not been able to do more than 4 cars with one. Also D300 is very expensive compared to other compounds. So there is a higher cost to the safety.

I have nothing against Rotaries, but for me, I really don't see a reason to take the risk of burning an edge to save what... 30 minutes out of the entire buffing process?

But in the end, I think you should use what you are most comfortable with. If you like using the rotary for paint correcting, then using the DA for polishing, then do that. It's probably the fastest way to go about it if you do a 2 or 3 step correction. In my world 1 step is king. People with daily drivers are usually not interested in having a 2 day correction done.

1 - In what case do you use it that you can't achieve results from your DA?
2 - How is it safer if the operator is proficient with each tool and takes all necessary preliminary steps?
3 - We are only talking about 2 step corrections in this discussion (not a one step) because even if you use a heavy cut with microfiber pad, there will still be some DA hazing from this process that you need to finish off.

[jslym777]

21 MKII cuts more than PE-14 and LH19E. Its the fastest tool I own. All tools can get the job done and with the abrasives and pads we have available a rotary is no longer faster.

If it cuts faster than the rotary, then how is it safer?

[Ronin47]

If it cuts faster than the rotary, then how is it safer?

It can level defects faster without burning paint. Leveling a defect and burning through are two different things, burning is excessive heat which is not related to cut.

Sanding a piece of wood and setting it alight are different things, both generate some form of heat, get the picture?

[mwoywod]

21 MKII cuts more than PE-14 and LH19E. Its the fastest tool I own. All tools can get the job done and with the abrasives and pads we have available a rotary is no longer faster.

Faster than cutting with a rotary? I believe that the 21 MKII offers the more correction than a rotary on open flat panels, but the 21mm orbit still makes it completely impractical for correcting every surface on most modern vehicles. Unless you're working out of a body shop and all the panels are disassembled? If not, I assume you're using a multi-tool approach which for me takes a lot more time.

[Joel1979]

It can level defects faster without burning paint. Leveling a defect and burning through are two different things, burning is excessive heat which is not related to cut.

Yeah, i wonder how many times it has to be said.

[jslym777]

https://www.instagram.com/p/BT-HDo0DjJa/

I have done many tests rotary vs wool and here is one

I would always expect to do a second step after using a wool pad on a rotary, so this doesn't follow my chain of discussion, nor does it show an even comparison. I would always agree that if it is light polishing a single step is the way to go. But, what we are talking about here is heavy compounding (two step process).