Porter Cable 7424XP... spins like a rotary. what gives?
#1
Burning Brakes
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So i was given a 7424XP for xmas and finally broke it out last weekend. I put a backing plate on it and a new uber pad to glaze the car. I was expecting it to vibrate and leave a half moon shape trail.... but instead it is spinning like crazy and unless i put a ton of pressure on it - it continues to spin. Could i be doing something wrong?
#2
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The XP uses the same motion as the previos 7424 but it's far more powerful thus it will spin the pad and you will need to be more careful around rubber trim and near the edges of paint. I tape off much more since I started using the XP to insure that I don't burn or damage any edges.
Makes me wonder how powerful the Flex is in comparison.
Makes me wonder how powerful the Flex is in comparison.
#3
Burning Brakes
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so more spinning than vibrating is normal? I have used other random orbit polishers and they spin a bit but nothing like this. I can put most of my weight on it and it stops spinning but the vibrating is more a motor fatigue feeling than a random orbit feeling
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Ryan,
The head should definitely oscillate and it will vibrate but it is a smoother machine than the first generation 7424. For reference mine will also spin even with the pad half compressed (medium pressure) while using a cutting pad and Meguiars M105 although mine is a Griots version (rebadged 7424Xp).
The head should definitely oscillate and it will vibrate but it is a smoother machine than the first generation 7424. For reference mine will also spin even with the pad half compressed (medium pressure) while using a cutting pad and Meguiars M105 although mine is a Griots version (rebadged 7424Xp).
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A Dual action machine (random elliptical centripetal orbit ( OPM) is one that has two controlled components of the backing plate / pad; orbiting around a centre spindle, while the baking plate / pad freely spins on its own axis. The backing plate mounting is off-centre, as the drive rotates centrifugal force moves the backing plate in an elliptical motion, to balance this motion a counter weight is fitted to counteract machine vibration
The pad rotation of a duel-action is driven by its orbital speed. The faster the machine orbits, the more centrifugal force is applied to the backing plate, which results in its random elliptical centripetal orbit (OPM). A pad with a large contact area absorbs the orbital action due to its high surface resistance. A 5.5-inch foam pad has much less surface resistance than its equivalent 6.5-ich pad and will provide better correction
The pad rotation of a duel-action is driven by its orbital speed. The faster the machine orbits, the more centrifugal force is applied to the backing plate, which results in its random elliptical centripetal orbit (OPM). A pad with a large contact area absorbs the orbital action due to its high surface resistance. A 5.5-inch foam pad has much less surface resistance than its equivalent 6.5-ich pad and will provide better correction
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At what rate is it spinning? If it is anything like the el-cheapo polisher I used to use, it may spin in the tens of RPMs per minute, if that...nothing like any other rotary power tool. If I held the edge of the pad, it would stop spinning.
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It's nothing like a sears buffer or similar, it is definitely a powerful tool and you could easily burn your fingers on a spinning pad.
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#8
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well i figured it out.... when i put the backing plate on I missed putting a spacer on. I took it apart and put it on and it works perfectly now. so odd...