MT300 question on spinning

[thedoc46]

So I used my MT300 properly today for the first time on a friends pretty heavily oxidized and swirled up 2008 Hyundai Sonarta. Did a wash, dry and clay using QD as a pre-requisite. I took off a lot of contaminates from the car.

I did notice though that if i applied any pressure on the MT300, it would only oscillate and not spin.. Only when i gave it hardly any pressure would it spin... I was under the understanding that for swirl removal, about 15lb of pressure should be applied and it needs to spin... I was on the 2nd from highest setting speed wise...

I was using a 5" backing plate and the 5" Meguiars maroon pad, with Ultimate Compound. It really did come out nice.. After giving it a few passes with hardly any pressure (thus spinning the compound in) I guess there were still some light swirls in the bright sunlight, but it looked a million times better than it did before i went to town on it... I finished off with a ULW.

Advice on the spinning / pressure for paint correction please. If the surface was completely flat, i could add more pressure and have it spin, but how many panels are there on a car that are completely flat? No many...I remember seeing a video (on a different DA Mike Phillips was using, mentioning, that if it wasn't spinning, then it wasn't removing the swirls.) Hence my post.

Thanks in advance.

[Selectchoice]

Re: MT300 question on spinning

Are you keeping the pad flat to the surface? Tilting of the pad can be easy to do and will surely stop the pad spinning on a DA machine.

[The Guz]

Re: MT300 question on spinning

Good point. I had no issues using mine at 5800 OPM's.

[thedoc46]

Re: MT300 question on spinning

Are you keeping the pad flat to the surface? Tilting of the pad can be easy to do and will surely stop the pad spinning on a DA machine.

I was, however on a car there are many curved panels, so unless you're working on a certain part of the hood or roof or side of a door, you're going to encounter a curve. As soon as i relieved pressure it spun up fine... But applying downward pressure, it wanted to oscillate more-so that spin.

[The Guz]

Re: MT300 question on spinning

That's typical of any DA unless you have a flex with forced rotation.

[thedoc46]

Re: MT300 question on spinning

That's typical of any DA unless you have a flex with forced rotation.

Funny enough it was a flex I watched a video on, when Mike Phillips said about 15lb of downwards pressure and you want to see it spin. Hence my OP. So is it fair to say with the MT300 for swirl removal, just keep it with light pressure to obtain maximum spin or press down with 15lb of pressure and have it mainly oscillate ?

[Michael Stoops]

Re: MT300 question on spinning

It is critically important, with any random orbital DA polisher, that you keep the pad flat against the paint in order to maintain pad spin. The MT300 is a torque monster and with the pad flat against the paint you can almost stand on it and still keep the pad rotating. Of course, that's when the tool is set at 4800opm or higher, as lower speeds don't provide the same level of torque (that should come as no surprise to anyone since this is basically true of virtually any type of motor running at lower speeds/lower amperage). Then again, lower speeds are generally used for things like finish polishing or wax application and torque is not really needed for those applications. But if you're correcting defects, you should be running at 5800opm at least, and at that point the MT300 is just loaded with torque. But, just like any other random orbit DA, as soon as you start leaning on an edge the rotation will stop. Working on a curved surface can mimic putting the tool on edge, so convex surfaces should be treated by keeping the center line of the pad in contact with the panel as shown in the video below. Note that at roughly the 00:11 mark I lift my hand off the tool momentarily and then I put it back, using pretty significant pressure. The pad continues to rotate.




When working on primary panels, while it's true that you very rarely find a totally dead flat panel on any car, you still want to keep the pad essentially flat against the panel. But as the panel curves you need to move the tool to mimic that curve in order to maintain that full contact. On this car, the hood sloped down at the front and to both sides. The tool can not remain parallel to the ground, but parallel to the hood. We see people doing the former during many Saturday classes, primarily because they tend to tense up a bit when first using the tool. When they tense up, not only do they not follow the contours of the body panels, but they tend to lock their upper bodies so that when moving side to side they sort of pendulum at the waist, and the tool arcs over the paint instead of staying flat. Again, they lose pad spin on the extreme sides of their work area when doing this. In the video below you can see that I actually cause a deformation of the hood due to the pressure I'm using, yet the pad never stops rotating. And I'm using pretty significant pressure here. You can also see how small the work area is, and how slowly the tool is moving across the paint. In some cases you may want this work area to be even smaller, and the speed across the paint even slower.

[DasBurninator]

Re: MT300 question on spinning

So is it fair to say with the MT300 for swirl removal, just keep it with light pressure to obtain maximum spin or press down with 15lb of pressure and have it mainly oscillate ?

If the pad is not spinning you aren't doing any correcting. Ease up on the pressure. Mark your backing plate so you can see it spinning.

[thedoc46]

Re: MT300 question on spinning

It is critically important, the pad flat against the paint you can almost stand on it ...........

Thanks Mike, you probably hit the nail on the head on my body being probably too stiff. It was my first real usage.. I do need to get some more cars under my belt and get a better feel for the technique. Even with light pressure the car came out stunning.... I will work on my technique...

[Michael Stoops]

Re: MT300 question on spinning

Thanks Mike, you probably hit the nail on the head on my body being probably too stiff. It was my first real usage.. I do need to get some more cars under my belt and get a better feel for the technique. Even with light pressure the car came out stunning.... I will work on my technique...

Honestly, I see this all the time with new users. They tense up, sometimes getting what I like to call "the Incredible Hulk grip" on the tool - I can see their muscles flexing in their arms as if they think the tool is going to run away from them. In reality, you can control the MT300 with one hand, and a light grip with that one hand to boot. You really need to be loose in the upper body and feel the flow of the body panels, move with the curves of the car. This is one aspect of working on a new to me car that I love - you gain a whole new appreciation for the curves and contours of a car when you let your body flow with it. It's amazing how subtle some compound curves can be on some cars and you almost don't notice it until you start polishing that paint.

Technique is critical with a DA polisher in order to accomplish anything. You can look at importance in technique with a DA versus a rotary like this: If your technique is poor when using a DA you just don't get the results you hoped for; if your technique is poor with a rotary you get to know the guy at the body shop because he'll be fixing all your burn throughs.

[DasBurninator]

Re: MT300 question on spinning

Honestly, I see this all the time with new users. They tense up, sometimes getting what I like to call "the Incredible Hulk grip" on the tool - I can see their muscles flexing in their arms as if they think the tool is going to run away from them.

I think this is from people expecting all polishers to be like a rotary. More so with the MT300 and Rupes since they look like a larger bodied rotary polisher.

[The Guz]

Re: MT300 question on spinning

Good videos Mike.

[mohebmhanna]

Re: MT300 question on spinning

Excellent video - Mike. I like the way your upper body moves with the DA to keep the pad spinning.

[thedoc46]

Re: MT300 question on spinning

I like watching the videos. Do you have any doing the more intricate slimmer parts of the body such as a pillar ? or around the front bumper. So we can see from a technique perspective how to do it properly ?

[h_bomm]

Re: MT300 question on spinning

That would be nice to see some videos tips on techniques and product demos for those (myself included) that can't make it to a TNOG. I'd love to attend one, but I live in central Minnesota, so it's a tad out of the way on my way home from work!