Does DA power even matter?

[Redcar GUY]

I was reading the Back of the Bottle and it said that it was good for Plastic and other interior pieces...... So I thought that I would try it on my Kenwood rack System that is in the garage. I was wayyyy dusty and had a few specks of white paint on it from me painting the garage... Anyhow I sprayed it on a rag and started wiping it down, I worked really good! I took off all the paint specks and took off the dust with no problem! Also make the plastic shine up nice....







Looks good for 11 years old.....

 

[PorscheGuy997]

Hey folks,

After recently adding a third DA polisher to my arsenal, I have to wonder. Does DA power make a difference or is it a psychological feeling?


As in any industry, there are ways of tweaking the figures. Because the DA market is fairly closed, there is no defined measurement of power. Many power tools advertise the maximum power rating. Others rate their motors at the normal running power. Why do some companies do this? Well, they can post a higher maximum power rating than a running power rating. For example, a certain retailer would rate their air compressors at a higher horsepower than the competition. How was this accomplished? They used the max horsepower, instead of the running horsepower.

I have a beater 7336, a prototype G110, and a Griot's. During a recent polishing of our Expedition, I used the Griot's for one side and a 7336 on the other side with a MF Cutting pad and M205. Both sessions were timed. While the time for the Griot's was faster by five minutes, this could have been easily attributed to fatigue.

So, to dive into the question...
Does more power save time? Does a higher amperage reduce the number of passes required? Can more power remove more defects?

After using some supposedly higher power DA polishers, I have come to the conclusion that the idea of a more powerful machine is more of a psychological marketing tool. For example, I can't even tell the difference in power between my 7336 and prototype G110. Had I not read that the G110 has a tick more power, I would not have even realized a difference.

To me, build quality, comfort and reliability are much more important than the supposed amperage. If the technique remains the same, the time spent polisher should remain the same. At the same time, if a lower powered DA could not remove the defects, a higher powered machine will perform the same.

In my opinion, the most important thing is technique. The level of bearing resistance is second in determining performance.

What do you folks think?

-Chris

 

[bmw5541]

Chris,
If the DA has more power, doesn't that mean it is less likely to bog down under pressure?
I don't know, I'm just asking.

 

[jaymz]

Last summer I bought a Griots 6" DA to replace my PC 7336. I was amazed at the difference in "power." I was able to use much more pressure without stopping the pad from spinning with the Griots. This made paint correction faster and allowed me to achieve results that I was not able to achieve with the PC.

Do I have any timed "measurements?" No. Do I finish in half the time? No. But for me the Griots was a paradigm shift.

Jim

 

[gmblack3]

For surbuf pads, it does not matter. You are applying "weight of the machine" pressure to get the best results with the surbuf pads. Any r/o will do.

KBM via orange flat pad/M105 power matters more to me then using MF pads. You still need some pressure with the MF pads, but not as much as you think.

Todd Helme has an old beat up 7424 or a 7336. When we detailed that Bugatti, I got to use it right against the GG that I brought with me. I swear and Todd felt the same, that under pressure his old PC had more power then the GG. :-t

I have a 7424 at home that I dont use that much anymore, it does not have the power of Todds old PC.

So YMMV!

But can I finish a car faster with a GG then a 7424 using the MF pads? Usually yes, but how much time am I saving.....Not much.

 

[imported_RaskyR1]

For surbuf pads, it does not matter. You are applying "weight of the machine" pressure to get the best results with the surbuf pads. Any r/o will do.

KBM via orange flat pad/M105 power matters more to me then using MF pads. You still need some pressure with the MF pads, but not as much as you think.

Todd Helme has an old beat up 7424 or a 7336. When we detailed that Bugatti, I got to use it right against the GG that I brought with me. I swear and Todd felt the same, that under pressure his old PC had more power then the GG. :-t

I have a 7424 at home that I dont use that much anymore, it does not have the power of Todds old PC.

So YMMV!

But can I finish a car faster with a GG then a 7424 using the MF pads? Usually yes, but how much time am I saving.....Not much.

Agreed. When downward pressure is needed you need a tool that can keep the pad rotating....whether it's a more powerful motor or something else, the tool that can do that wins in my book. If it can do it with less noise and vibration, even better!

Bryan....I have heard the story of these "rare" PC7424's that are the "beast" of their time, but unfortunately mine is also not one of them. Muscleman

My GGDA definitely has more power under load then both my PC's, even when on lower speed settings, but the build quality is crap IMO!

I'm on my Second GGDA in 2 months, and my new one is currently being held together with epoxy and duct tape after committing suicide off my stool (24" max)!

I also recently recommend the GGDA to a friend and it broke during his first use and now has to wait for a replacement to come out before he can finish his car. Both my PC's are still going strong after many high dive attempts and the original one is over 6 years old!


I'm thinking of trying the G110v2....

 

[imported_detailchick]

Real men use Rotarys :-B

No , real men use their bare hands and work shirtless!Muscleman

 

[imported_Bunky]

No , real men use their bare hands and work shirtless!Muscleman

So what do real women use?

 

[imported_User Name]

Great thread Chris and contributions by Chad and Bryan.

Schmucks like me rely on the good info you guys post. Thanks.

 

[imported_Kevin Brown]

User Name, you are the funniest guy on these forums.

Little jewels are sprinkled all over... avatars, sigs, ID... 2funE !!!

gmblack3a is a close second in the MOFW dept.

 

[Todd@RUPES]

Todd Helme has an old beat up 7424 or a 7336. When we detailed that Bugatti, I got to use it right against the GG that I brought with me. I swear and Todd felt the same, that under pressure his old PC had more power then the GG. :-t

I have a 7424 at home that I dont use that much anymore, it does not have the power of Todds old PC.

.

That's my old Meg's G100 (identical to the 7242 minus the label)... Shhhh....

I actually ran it over once and that is what kicked it into the super mode. I have polished along all of the new polishers and IMO it has always been able to spin the pad faster (looser bearing) then all of the new machines and has always kept up with for maximum correction.

 

[Todd@RUPES]

Here is an answer I typed a couple of weeks ago.

Just food for thought...

The power of the machine has *nothing* to do with the pad's spinning rate (RPM). The reason I *'d nothing is because it obviously has something to do with it, but the effect is very indirect.

What makes the pad spin is the size (stroke) and speed of the orbit. Think of the orbit like a bicycle pedal. The distance from the pedal to the axle would be considered 1/2 the stroke. Since the pedal orbits the axle on both sides, we add the distance together to get the stroke.

And this is why power rating of a machine is slightly misleading. Regardless if a machine has 1 horsepower or 5000 horsepower, if it is able to maintain full OPM (orbital speed) under pressure then it will spin the pad the same rate, regardless of pressure. Granted the 1 horsepower machine will likely be working much harder to achieve that speed (more % of its potential).

The power of a machine can potentially resist how much the speed decreases when friction is applied to the orbital motion. I don't care how hard you press down on a 5000 horsepower DA, you aren't going to bog it! But here is the catch, the orbital action (5/16th stroke) is fairly efficient and even under pressure it is hard to slow the orbital motion down. Most of the friction (that stops the pad from spinning) is taken up in the bearing of machine. The only real force acting to bog or slow the orbital speed is the internal flex inside the pad. A firm, thin pad is going to transfer more of that friction (from the paint) directly to the orbital motion where as a oversized squishy foam pad is going to jiggle on itself and absorb the friction. It gets a little confusing (which is why pad dynamics play such a HUGE role in DA polishing) but a big, tall foam pad will stall the spinning easier (since their is more friction at the paint's surface) but most of that friction will be absorbed by the foam, which can make it harder to stall the orbital motion.

Most modern DA's are rated at 6800 OPM maximum and most (because of pad dynamics) will maintain that orbital speed under significant pressure, regardless of how much power it has in reserve. Since the pad's rotational speed is a function of the stroke and orbital speed, if a weak machine and a strong machine both have a 5/16th's stroke and both are able to maintain a consistent orbital speed of 6800 OPM, the both will spin the pads at the same exact speed.

If pressure is applied, but neither machine looses speed, then even under pressure, both machines will perform the same.

The only advantage you are likely to see is under extreme down pressure, enough to actually cause significant drag on the orbital motion. In this case the stronger machine will maintain more orbital speed, which will will make the pad want to spin more. However at this pressure level it is very likely that the pads have stopped spinning anyways (it takes a lot to bog the orbital motion action of a machine. I know it sounds like they bog (changes in noise) but the actual change is speed is very very little.

Enough theory for one day, I'm exhausted!

 

[imported_Bunky]

Enough theory for one day, I'm exhausted![/FONT][/COLOR]

I appreciate theory and makes sense but why does almost anyone that uses the Griot's think it works better despite its construction (housing, etc). This tells me that it in some tangible manner bogs down less...ability to maintain the orbital motion.

 

[Todd@RUPES]

I appreciate theory and makes sense but why does almost anyone that uses the Griot's think it works better despite its construction (housing, etc). This tells me that it in some tangible manner bogs down less...ability to maintain the orbital motion.

To be honest I really don't read other forums and I have no idea what the general consensus is (although I certainty will not disagree with other's results). All I can say is I have several friends (David Fermani and Bryan Burnworth amongst others) who have GG DA, and when we have polished side by side they the correction level and rate was equal. I have also polished side by side with several lesser know forum members who both swore that their GG was more powerful but when tested them side by side we found the correction levels to be similar.

Does the more powerful GG resist orbital bog better? It should. How much? I would guess very little (at least based on my rudimentary understanding of physics). Again, in my experience, side by side, I have not noticed (nor did they) any significant difference in the rate of pad rotation. The Griot's may have been slightly faster under EXTREME pressure then a G110v2, but it was not easy to notice.

 

[imported_Bunky]

...All I can say is I have several friends (David Fermani and Bryan Burnworth amongst others) who have GG DA, and when we have polished side by side they the correction level and rate was equal. I have also polished side by side with several lesser know forum members who both swore that their GG was more powerful but when tested them side by side we found the correction levels to be similar.

Thanks. The side by side comparison information is what really counts as long as it was an apples to apples comparison (same size pads/ polish/pressure).

 

[Greg Nichols]

For surbuf pads, it does not matter. You are applying "weight of the machine" pressure to get the best results with the surbuf pads. Any r/o will do.

KBM via orange flat pad/M105 power matters more to me then using MF pads. You still need some pressure with the MF pads, but not as much as you think.

Todd Helme has an old beat up 7424 or a 7336. When we detailed that Bugatti, I got to use it right against the GG that I brought with me. I swear and Todd felt the same, that under pressure his old PC had more power then the GG. :-t

I have a 7424 at home that I dont use that much anymore, it does not have the power of Todds old PC.

So YMMV!

But can I finish a car faster with a GG then a 7424 using the MF pads? Usually yes, but how much time am I saving.....Not much.

Kevin Brown and I did a quick test at SEMA this past year, I have an OLD PC and under load it kept its rotation MUCH better than the new pc, the megs v1 or v2. While we didn't create quantifible measurements it was clear to us the old PC's have more torque.

A few weeks ago my brother and I did his car, he was a NOB with a RO machine, he used a V2 from his neighbor and I used my OLD PC. We traded machines he noticed right off, without me asking......... your machine is much more "powerful" and easier on the wrists "less vibration".

I've heard good torque from the Griots, but the build quality sounds iffy?

Cheers,
GREG

 

[[email protected]]

This is a very interesting discussion. When you guys say "old" PC (Porter Cable), how old? 10-15 years? 5-10?

Also, how hard are you guys pressing down on the pads? I rarely use much pressure. I hold it down just enough to 'stall' the pad on the surface. The pad will jiggle, but not rotate around very fast.

Thanks!!!

Johnny

 

[imported_Bunky]

The old pc being more powerful than even the XP, v2, goes against even more marketing. I recall all those charts showing rpm, opm, etc. and ability to continue to drive the pad even under pressure.

I can understand how Meg's basically zeroes out the DA as a variable by designing a system around a specific machine so that variable is fixed.

 

[imported_User Name]

User Name, you are the funniest guy on these forums.

Little jewels are sprinkled all over... avatars, sigs, ID... 2funE !!!

gmblack3a is a close second in the MOFW dept.

You are confusing sense of humour with my general stupidity. It is hard to believe someone understands as "little" as I do!

A lot of my comments here stem from (a great) article you wrote about RPM's and OPM and orbit size and a bunch of other things that went over my head. I remember that at least (in part) you thought the G110 v2 compared quite favorably to the other machines. Of course, I can't even pretend I know how you came to your conclusion!