Planex drywall sander jumps around

[NFMudder]

I just purchased a PLANEX LHS 225 Drywall Sander and made my first pass on a finished wall. The sander started to bounce and destroyed the finish. What am I doing wrong? Adjusting the suction and speed didn't help.

 

[leakyroof]

Which abrasive and which grit? Also, that Sander has a learning curve like most tools , so practice with it on a wall that's not finished or maybe even set up a joint/compound seam to sand on a wall that you won't freak out if you struggle a bit to learn how the sander works with you. 

 

[NFMudder]

I was using the supplied pad. I will switch to the soft pad and see if that helps. I used fine and aggressive paper with the same result. I love the quality of this tool and will keep trying until I get it right.

 

[leakyroof]

I was using the supplied pad. I will switch to the soft pad and see if that helps. I used fine and aggressive paper with the same result. I love the quality of this tool and will keep trying until I get it right.

. Let me clarify, were you using Granat Abrasive, Saphir, or the now-discontinued Brilliant 2?  Next , the suction on the head can be adjusted two different ways, independently of the suction level dial on the main body of the sander. With a smooth surface, and fine paper , you may need to switch between a Perimeter suction or the Centered suction to see where the sander works best for you.
Next, is your vacuum adjustable for suction level like a Festool or a Fein vac?  Occasionally I will need to adjust my vac and the dial on the sander to get what I want. Most of the time, just adjusting the sander suction dial does it for me.
Handling the Sander. It's a Rotary sander, no Random Orbit, so try out how the direction of the pad can work with you or against you if you are trying to fight it.
I think for me , it's a bit like a larger, slower version of Festool's RAS 115 sander, the rotation has to be watched when you're swinging the sander left and right or up and down a wall.
You'll get it with some practice , and there are some experienced users here who can better describe what you might be running into with your Planex than me.

 

[NFMudder]

I did purchase the Festool self cleaner vac as well. I think my problem may have to do with going against the rotation. I will keep working at it. I have tried the Granat Abrasive and Saphir. I am a former Porter-cable user but I decided to step up my game. Thank you for the advice

 

[Saskataper]

There is no question you need the soft pad kit. The planex is useless without it. 
The planex will sometimes jump when you go over a really I ever surface like a hump. It takes some practice but once you get the hang of it you can fly. I run 220 grit but you might want to start with 240

 

[imaginarynumber]

I have a Rotex 125 that jumps all over the place.

I have used other ones that behave fine (using the same abrasives/extractors/surfaces.

Read in to that what you will

 

[leakyroof]

I have a Rotex 125 that jumps all over the place.

I have used other ones that behave fine (using the same abrasives/extractors/surfaces.

Read in to that what you will

. For what it's worth, that's the only way a Rotex 125 has behaved for me any time I have tried to sand with one. My RO 150 is more manageable.

 

[imaginarynumber]

I have a Rotex 125 that jumps all over the place.

I have used other ones that behave fine (using the same abrasives/extractors/surfaces.

Read in to that what you will

. For what it's worth, that's the only way a Rotex 125 has behaved for me any time I have tried to sand with one. My RO 150 is more manageable.

I have been more than happy with both of my 150mm Rotex sanders.

I now only use the 125mm Rotex with 320 grit Titan to sand acrylic primer on (flat) MDF using the interface pad.

A friend has two 125mm Rotex sanders, neither of his jump around.

 

[Throwback7r]

Only jumps for me when I move it too fast, or don't have the suction up high enough. I just removed texture from an entire cathedral ceiling, started with 80 grit and worked down to 220.