Backup Pads & Hole Patterns: How to Match Indasa Discs to Your Sander
Sanding discs only perform if they match your backup pad and sander. This guide explains disc attachment types, hole patterns for dust extraction, and how to choose the right Indasa backup pad for your tool.
Step 1: Match the attachment
Discs attach two ways, and the disc must match the pad face:
- Grip (hook & loop / Rhynogrip) — needs a hook-faced backup pad; reusable.
- PSA (self-adhesive / Rhynostick) — needs a smooth backup pad; single-use peel-and-stick.
Step 2: Match the size
Use a disc that matches your pad diameter — most commonly 5" or 6" for random-orbital (DA) sanders, with 3" used for spot repair. The disc and pad diameter should be the same.
Step 3: Match the hole pattern (for dust extraction)
If your sander uses dust extraction, the disc holes must line up with the pad and tool to pull dust through. Common patterns include 5-hole, 6-hole, 8-hole, 9-hole (Festool-style), and multi-hole / universal patterns. Indasa multi-hole and Ultravent discs use many holes to fit a wide range of dust-extraction pads.
| Sander / setup | Typical disc choice |
|---|---|
| 5" DA, central vacuum | 5" grip, 5- or 8-hole (or multi-hole) |
| 6" DA, central vacuum | 6" grip, 6- or 8-hole (or multi-hole) |
| Festool 6" | 6" grip, 9-hole or multi-hole (Festool pattern) |
| Non-vacuum DA | Solid (no-hole) grip or PSA disc |
| Spot/edge repair | 3" grip or PSA disc and matching pad |
Interface pads
A soft interface pad fits between the backup pad and disc to help conform to curves and soften the scratch for fine finishing. Match its diameter and hole pattern to your pad.
Frequently asked questions
How do I know what hole pattern I need?
Match the disc hole pattern to your backup pad and dust-extraction holes so dust is drawn through. If your pad has a multi-hole pattern, a multi-hole or universal disc is the safest fit.
Can I use a grip disc on a PSA pad?
No. Grip (hook-and-loop) discs require a hook-faced pad, and PSA discs require a smooth pad. The attachment type must match.
What disc fits a Festool sander?
Festool 6" sanders typically use a 9-hole or multi-hole grip disc that matches the Festool hole pattern; Indasa offers multi-hole discs designed to fit.
What if my sander has no dust extraction?
Use a solid (no-hole) disc. Holes are only needed to pull dust through an extraction pad.
What size disc should I use?
Match the disc diameter to your backup pad — commonly 5" or 6" for DA sanders and 3" for spot repair.