Sanding Sequence PlannerSanding Grit Sequence Planner
Plan the correct grit-by-grit sanding sequence for any wood and surface condition. Builds a step-by-step progression from coarse to fine that never skips a grade, for a flawless finish-ready surface.
Why this calculation matters
The grit sequence decides how the finish looks and how many hours the finishing stage takes. Skipping a grit costs more time in the next one than it saved.
Sanding Sequence Planner
Sanding Grit Sequence Planner
Coarser for rough or damaged surfaces.
| Step | Grit | Purpose |
|---|
About Sanding Sequence Planner
A flawless finish starts with correct sanding. The golden rule is never to skip more than one grit grade - each grit must remove the scratch pattern left by the previous one, progressively refining the surface. This planner builds the right grit-by-grit sequence for your wood and surface condition, from coarse stock removal through to your chosen finish grit. If you have ever wondered what grit sandpaper to start with, the sanding grit progression here removes the guesswork for any finish level.
Where Is This Used?
Method & Rules
Progress through grits: 80 -> 120 -> 150 -> 180 -> 220 ...Never jump more than ~one grade (avoid over ~1.7x increase)Each grit removes the scratches of the previous gritAlways sand with the grain, not across itRemove all dust between grits to avoid stray coarse scratchesHow the calculation works
Each grit only removes the scratches left by the one before it. Jumping a grade leaves scratches the finer paper cannot reach, and they become visible the moment stain or finish goes on — which is why the planner fills the gap rather than accepting the jump.
Show the formula
The sequence is built from the standard grit series and refined so that no step skips a grade: where a jump exists, the intermediate standard grits between the two are inserted.A sequence rule, not a physical calculation. Stopping point depends on the finish: most water-based coatings want 180-220, and sanding finer can burnish the surface and reduce adhesion.
References
No external standard governs this calculation — it is arithmetic from your inputs. Take product-dependent figures from the manufacturer data sheet, not from here.
Limitations of this calculation
Plans grit progression only. It does not account for existing surface condition, species-specific burnishing, machine versus hand sanding rates, or the additional passes needed after grain raising.
Do not use this for Warranty-critical finishing, where the coating manufacturer specifies its own preparation.
Figures are engineering estimates from the inputs and assumptions shown. Verify against the actual material and, where the result affects structure or safety, against a qualified professional.
- Ascending grit progression
Formula checked against the sources above by an automated regression test (tests/verify-phase2.js) that derives each expected value independently of this page. Last reviewed .
How to use this tool
- Enter the job details below, then press Calculate.
- Pick your surface condition and finish target from the dropdown.
- Press Calculate.
Worked example
Common mistakes to avoid
- Skipping grits. Jumping from 80 to 240 leaves scratches that only show up after staining.
- Sanding finer than the finish needs. Beyond about 180–220, many stains stop absorbing evenly.
- Using the same sequence for softwood and hardwood. Soft woods clog paper faster and burn easier.
Frequently Asked Questions
Wood species data
Density, hardness and movement for 60 timbers