Pad #20425 Dual Action & Random Orbital Sanders
One of 3M's most popular 6" Hookit pads, this low profile pad fits all standard (5/16-24 thread) sanders.
It utilizes a soft foam construction for fine finish sanding, and offers outstanding conformability to contours and curves.
Recommended for use with finer grades of Clean Sanding abrasive discs.
Ideal for finish sanding of topcoats, etc.
Note that although only the large vacuum holes are open on the back of the pad, they connect to every small hole on the face of the pad via internal channels, for a true full Clean Sanding hole pattern benefit.
Designed for Clean Sanding abrasive discs, but can be used with any 6" Hookit abrasive disc
Very flexible edge - suitable for hulls and other curved surfaces
Slightly tapered 15 beveled edge
Hookit pad face holds the disc securely, yet allows easy attachment and removal
Sold by the each; 10 per case
The Hook Saver for this pad is MMM 20445; see Related Products, below.
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.