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v12
Sep 3rd, 2005, 02:33 PM
I'm just wondering, when we want to polish a swirly car why we have to set the rotary speed to 1700 rpm? Do the heat fix the problem or the number of passes that we make on specific area?

Thanks

Mike Phillips
Sep 3rd, 2005, 05:00 PM
Originally posted by v12
I'm just wondering, when we want to polish a swirly car why we have to set the rotary speed to 1700 rpm? Do the heat fix the problem or the number of passes that we make on specific area?

Thanks

Who says you have to use the rotary at 1700rpm? We list using the rotary buffer in a range from 1000 to 2000 but that's up to the operator, it's not a concrete rule of thumb.

I've never read anything by Meguiar's, nor have I ever posted that stated heat was a necessary component of machine buffing. It's definitely a by-product, but not a built-in feature.

Removing defects, or in other words removing paint is a matter of the combination of pad selection, product selection and time and energy. Heat is generated and may be part of the process but it's a by-product of the process that cannot be avoided until you figure out a way to do something like inject the process with cold running water. Of course this would mean using an air-powered machine and not an electrical powered machine.

the other pc
Sep 3rd, 2005, 08:48 PM
Originally posted by Mike Phillips
...inject the process with cold running water. Of course this would mean using an air-powered machine and not an electrical powered machine. http://www.mkdiamond.com/images/hand_tools/1509.jpg http://www.mkdiamond.com/images/hand_tools/1503_case.jpg
The stone industry does wet polishing with electric machines; they do need to be double insulated and have ground fault circuit interrupters.

The machine may be similar to a rotary paint polisher but the actual process is different. The abrasives used are grinding wheels and a constant flow of water is used for cooling and lubrication. In paint polishing the product (compound, polish, cleaner, etc.) has the abrasive suspended in a slurry which is held against the finish by the pad. A flow of coolant would wash away the abrasive before they could do anything.

Manufacturing operations like lens grinding are done with continuous flow abrasive slurries. Those processes recirculate the abrasive liquid (unless you want to waste humongous volumes of expensive abrasives).


PC.

v12
Sep 4th, 2005, 05:43 AM
Thanks all for your reply,

Mike, actually I heard this in meguiar video tape! he said as I remember that if you use very high speed you may burn the paint and if you use too low speed it will not generate sufficient heat to fix the problem. and he recommend using the rotary ar speed of 1750rpm.

Mike Phillips
Sep 4th, 2005, 06:37 AM
Originally posted by v12
Thanks all for your reply,

Mike, actually I heard this in Meguiar's video tape! he said as I remember that if you use very high speed you may burn the paint and if you use too low speed it will not generate sufficient heat to fix the problem. and he recommend using the rotary ar speed of 1750rpm.

I'll look into that as I don't remember the video saying that and I wrote the script.

For the most part, the only time I know of where high speeds are useful and necessary are when a person is working on polyester or epoxy molds, in cases like this you're not working on a thin layer of paint, but on a thick layer of a hard substance.

Always remember paint is thin, even if you have extra coats, compared to the cutting ability of a cutting pad, a cutting compound and rotary buffer, paint is thin.

I'll read through the script and see what I can find. It could be that I'm wrong and heat is a necessary component of the cutting process, it won't be the first time I've made a mistake and it certainly will not be the last time.

probegt
Nov 9th, 2005, 08:51 AM
So if the there was no heat , would the diminishing abrasives would still break down?

Mike Phillips
Nov 9th, 2005, 08:56 AM
Originally posted by probegt
So if the there was no heat , would the diminishing abrasives would still break down?


Heat is not a necessary component of the cleaning process when using any of Meguiar's compounds, paint cleaners, cleaner/polishes or cleaners/waxes.

Heat is merely an unavoidable by-product of the process.


The answer to your question is "Yes".


All that is required to break the diminishing abrasives utilized by Meguiar's products is pressure over time.

probegt
Nov 9th, 2005, 09:11 AM
Thanks. Thats what I figured but I hear alot that products will not break down properly without heat. Do you think it might help aid in it?

Mike Phillips
Nov 9th, 2005, 09:35 AM
In most cases heat is more of a problem then a solution when working on thin, delicate coatings. So the answer would be no.

Mosca
Nov 9th, 2005, 02:26 PM
OK, then that begs the question: Why can't #84 and #85, and #s1/2/4 be used effectively with the G100? My understanding as well was that they required the heat of the rotary.

Mike Phillips
Nov 9th, 2005, 02:42 PM
Originally posted by Mosca
OK, then that begs the question: Why can't #84 and #85, and #s1/2/4 be used effectively with the G100? My understanding as well was that they required the heat of the rotary.

The dual action polisher doesn't have the power/force to effectively make use of the microscopic abrasives. It takes force/pressure to push them against the finish and cause them to simply put, take little bites out of the paint. This force/pressure of course then also causes these same diminishing abrasives to break down with time.

I think the key word here is effective. Remember, the goal isn't to push the product around on the surface, the goal is to remove defects and we do this by removing paint.

Rotary Buffer = Power with speed
Dual Action Polisher = Gentle and safe


There's a trade-off in there somewhere...

Pete-FWA
Nov 9th, 2005, 02:43 PM
I'm quoting Mike's above post: "All that is required to break the diminishing abrasives utilized by Meguiar's products is pressure over time."

This doesn't mean HEAT with the G100, it means being able to break down the abrasives. A rotary is a dedicated motion that can go faster in that circle of friction. This breaks down the abrasives. Heat is a byproduct of that friction.

zey
Nov 10th, 2005, 12:18 AM
Running rotary buffer at too high speed will cause paintwork to boil up and depends on paint type, some of it will show up blisters before it burns. This is more frequent on factory paintjob. I would still prefer the slow and steady way of rotary polishing, it might take longer time, but it's better to be safe than sorry.