Pad #20350 Dual Action & Random Orbital Sanders
This pad features the 3M Clean Sanding hole pattern for superior vacuum-assisted dust extraction.
It can, however, be used to back up ANY
3" Hookit abrasive disc (regardless of hole pattern), with or without use of a vacuum.
Has a 1/4-20 threaded mounting stud.
Thin, firm red foam with a slightly flexible edge allows for aggressive sanding - good for flatter surfaces
Appox. 45 tapered bevel provides some edge flexibility
Hookit pad face holds the disc securely, allowing easy attachment and removal
Sold by the each; 10 per case
Heavy on the technical side...
Should you use a soft or firm sanding disc backing pad?
After you have decided between Stikit or Hookit, and chosen no-hole or clean sanding discs, and selected the disc diameter, you will still often be left with the choice of a firm or a soft backing pad.
As a general rule, you should use coarser abrasive discs on firm backing pads, and finer grit discs on soft backing pads.
Soft Backing Pads
The advantage of a soft pad is that its surface can flex to some extent, conforming to the shape of the surface being sanded.
This facilitates higher surface contact, more consistent material removal, and less gouging.
Soft pads are not intended for use with very coarse abrasive discs for heavy duty work, as the higher stresses induced by very coarse abrasives fatigues the foam prematurely.
Having said that, a soft pad can
be used with coarse grit discs for heavy material removal on rounded surfaces - like a sailboat hull - where it would be difficult to maintain full surface contact with a stiffer, firm backing pad.
Just don't expect the soft pad to last as long.
Firm Backing Pads
Using coarse discs on a firm backing pad works very well, as long as the work surface is flat
Using a firm pad on a curved surface can easily result in hard-to-remove gouges and scratch marks.
If the surface isn't flat - again, like a sailboat hull - you will generally want to use a softer pad for full surface contact, no matter what the grit of the sanding disc.
Firm pads are also recommended for leveling uneven surfaces - such as paint brush strokes and runs.
In this application, a soft pad might simply conform to raised areas, rather than cutting them down.