Norton Norzon H815 Discs: How to Choose the Right Grit
By Supergrit Abrasives | Published: 2026-11-01
Category: Buying Guides
Match Norton Norzon H815 zirconia discs to the job: coarse grits for heavy stock removal, finer grits for blending and finishing. Use these decision rules.
Quick answer
Choose coarse Norton Norzon H815 grits when you need to remove weld, mill scale or heavy stock fast, and step to finer grits only after the surface is flat. If you are unsure, start one grit coarser than you think you need and refine from there.
Why grit choice matters more on heavy paper discs
Zirconia grain cuts aggressively and keeps cutting as it fractures, so a coarse zirconia disc can remove a lot of material before it dulls. On heavy paper backing, that aggression is paired with a stiffer disc that holds its shape under pressure. The trade-off is that a coarse grit leaves deeper scratches that take more steps to erase, while a fine grit on a heavy paper disc may glaze or load before it finishes the job efficiently.
That means grit selection is really a sequencing decision: pick the coarsest grit that removes the defect, then move through intermediate grits only as far as the final finish requires. Skipping a step often costs more time than it saves.
Match grit to the defect, not the material name
A common mistake is choosing grit by metal type alone. Instead, look at what you are removing. Weld spatter and heavy mill scale call for a coarse starting point; scratch blending and edge cleanup call for a mid-range grit; final cosmetic blending calls for a finer grit. The same steel may need different starting grits depending on whether it is new plate or a repaired weld.
Because the catalog does not list a full grit range or recommended applications for every option, treat the grit chart as a starting point and confirm your sequence on a scrap piece before committing to a full batch.
PSA backing changes how you plan the sequence
Pressure-sensitive adhesive discs stick flat and stay put, which suits heavy paper discs that see high pressure. But PSA also means you cannot peel and reposition a disc mid-pass the way you can with hook-and-loop. Plan your grit changes so each disc is used for one stage, and keep a dedicated backup disc for each grit you rely on.
If you change grits often on the same sander, PSA can slow you down. In that case, keep the coarse work on PSA discs and use a quicker-change system for the finer blending steps.
Grit selection decision rules
- Start coarse for weld and scale: If you are removing weld spatter, heavy mill scale or gouges, start with the coarsest grit available in the Norton Norzon H815 line and work until the defect is gone. Do not jump to a finer grit while the defect is still visible. Check the surface under good light before changing grit.
- Step through one intermediate grit: After coarse removal, use one intermediate grit to erase the coarse scratches before moving to a finishing grit. Skipping the intermediate step usually leaves deep scratches that show through the finish. If the intermediate disc loads quickly, reduce pressure rather than skipping the step.
- Finish only as fine as the job requires: Choose the finest grit that meets the visible finish requirement, not the finest available. A finer grit on heavy paper may glaze before it removes the previous scratches, wasting both time and discs. Stop when the surface meets the specification, not when the grit chart ends.
- Match disc size to sander and access: Select the dimension that fits your sander and reaches the area you need to work. A disc that is too large for the space can leave the center of the work untouched. Confirm the backing pad size before ordering a full box.
Product facts
- SOLID PSA ZIRCONIA NORTON NORZON H815 HEAVY PAPER DISCS: Solid PSA zirconia disc with heavy paper backing, available in multiple dimensions and grits. You can build a grit sequence from one product line, but you must choose the grit and size that match your sander and finishing step.
SOLID PSA ZIRCONIA NORTON NORZON H815 HEAVY PAPER DISCS
Who these discs suit
Best for
- Fabricators doing heavy stock removal, weld blending and scale removal on metal
- Users who want a flat, secure PSA attachment for high-pressure sanding
Not for
- Anyone who changes grits frequently on the same sander and needs quick swaps
- Finishing work that requires very fine, flexible discs beyond the available grit range
