It fits but there's no safety margin at all. The edge of the backing plate fits right to the edge of the Velcro on a 5.5" pad.
Can they be used. Yes. Do you want to be very, very careful? Yes.
Just to note, pad thickness isn't an issue with a Flex 3401 because it uses a forced rotation drive mechanism. Pad thickness is only a factor as it relates to DA polishers that use a Free Rotating Spindle Bearing Assembly.
Here's the point, if a person did want to use a 5.5" pad with a 5.5" backing plate, it would be a good idea to stick with thicker pads as this will position the backing plate farther away from the paint surface.
This would be especially true for any type of finishing pad because softer foams compress thus with compression a thin soft foam pad would put the edge of the backing plate very close to the paint.
To that point, these would be a good option if a person wanted to use 5.5" pads on a 5.5" backing plate.
I agree with Mike. (who wouldn't LOL! He's the master of the "Art of Detailing" ) I've used the 5.5" pads with my Flex 3401 but only on flat surfaces. As soon as I see some curvature, trim or contours I immediately stop. It's just too risky to damage and remove paint when that sharp edge of the BP hits anything.
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You know I learn everything in life the hard way. I did it once and nicked my paint. I then purchased the 4" Flex backing plate. Too risky for me using the standard backing plate with 5.5" pads.
I trimmed mine down in a lathe. But only after I bought a spare Flex backing plate in case I ruined the one I turned down. But it turned out fine. Just made a huge mess doing it.
I trimmed mine down in a lathe. But only after I bought a spare Flex backing plate in case I ruined the one I turned down. But it turned out fine. Just made a huge mess doing it.
did u turn it down into the plastic molding of the bp? do u think u would have been able to trim the Bp down even more to accommodate 4" pads? I know there is a smaller Bp yet coming out but I was just thinking to use my spare and get trim it down on the lathe. however the stock Bp has a buffer of foam-Velcro beyond the plastic housing of the Bp which I just trimmed off with a razor knife right up to the plastic .
I trimmed mine down in a lathe. But only after I bought a spare Flex backing plate in case I ruined the one I turned down. But it turned out fine. Just made a huge mess doing it.
did u turn it down into the plastic molding of the bp? do u think u would have been able to trim the Bp down even more to accommodate 4" pads? I know there is a smaller Bp yet coming out but I was just thinking to use my spare and get trim it down on the lathe. however the stock Bp has a buffer of foam-Velcro beyond the plastic housing of the Bp which I just trimmed off with a razor knife right up to the plastic .
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) I've used the 5.5" pads with my Flex 3401 but only on flat surfaces. As soon as I see some curvature, trim or contours I immediately stop. It's just too risky to damage and remove paint when that sharp edge of the BP hits anything.
Originally Posted by oldmodman
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