Calculator
Formula used
This selector estimates brush width using a scaled surface band and three modifiers.
- SurfaceBand_in = SurfaceWidth_cm / 2.54
- RawWidth_in = SurfaceBand_in × DetailFactor × ViscosityFactor × SurfaceFactor
- Recommended_in = nearest standard size to RawWidth_in
How to use this calculator
- Pick your application type and surface texture.
- Measure the typical width you brush in one pass.
- Select a detail level that matches your control needs.
- Choose viscosity based on the product you apply.
- Enter reach distance and the number of coats.
- Press Submit to see the recommended setup.
- Use CSV or PDF buttons to save results.
Example data table
| Application | Width (cm) | Detail | Viscosity | Texture | Recommended |
|---|---|---|---|---|---|
| Garden beds | 12 | General | Medium | Smooth | 2.00 in |
| Trim lines | 6 | Fine | Thin | Smooth | 0.75 in |
| Pots corners | 8 | General | Medium | Textured | 1.50 in |
| Tools | 10 | Fast | Thin | Textured | 2.50 in |
| Pruning seal | 5 | Fine | Thick | Rough | 0.50 in |
Selecting by surface band and control
A brush should match the typical band you cover in one pass. This calculator converts your measured width into a practical brush width and then rounds to common standards. For edges, a slightly smaller brush improves line control and reduces accidental over-brushing onto plants or hardscape. Use the swath output to estimate finishing borders safely.
Detail level and finish quality
Fine detail work benefits from a narrower brush because the bristle fan stays compact under light pressure. Medium settings balance speed and precision for bed borders, pots, and labels. Coarse settings deliberately widen the recommendation, helping you move more coating with fewer strokes when accuracy is less critical. If you notice pooling, step down one detail level for better control.
Coating viscosity and bristle stiffness
Thin washes and stains flow easily, so softer bristles lay down smoother films with fewer marks. Thicker sealants and pastes resist flow and can push bristles apart, so stiffer filaments maintain shape and deliver material into pores. The calculator combines viscosity and texture to suggest stiffness that matches the product's resistance. Rinse often when using sticky mixes to prevent bristle flare and dragging.
Surface texture, bristle length, and durability
Textured wood, masonry, and bark increase drag, which can shorten bristle life and create skipping. A moderate increase in effective width and bristle length helps keep the tip loaded while you work across high points and recesses. For rough bark or pruning seal, durable filaments and shorter, stronger bristles reduce shedding. Choose flagged tips on smooth surfaces to reduce visible brush lines.
Reach, ergonomics, and efficiency metrics
Handle length matters when you must extend past a comfortable grip zone. Longer handles improve access but can reduce precision, so the tool recommends a handle range based on reach distance. For edging tasks, strokes per meter provides a simple efficiency target: wider swath reduces strokes, but only until control declines. Pair long handles with angled heads when working behind planters or rails.
FAQs
1) Is the recommended width always the widest part I should brush?
No. It is a practical starting point. For delicate lines, drop one standard size for control. For broad, open areas, you can move up if coverage stays even.
2) What should I choose for detail level if I am unsure?
Select General work. It balances speed and accuracy for most garden edges, pots, and tools. After a test stroke, adjust to Fine for sharper lines or Coarse for faster coverage.
3) How do I decide coating viscosity?
Think about flow. Thin liquids drip and spread quickly. Medium products hold a bead but still level. Thick products feel paste-like and resist brushing. When in doubt, choose Medium and adjust after a small test.
4) Why does surface texture affect the brush size?
Rough surfaces create drag and absorb material. A slightly wider brush helps maintain a loaded tip and reach into recesses. Texture also pushes the stiffness recommendation toward firmer bristles for better shape retention.
5) What does strokes per meter mean?
It estimates how many overlapping strokes you need to cover one meter of edging. Lower values mean faster work. Use it as a planning metric, but prioritize clean lines over speed for visible borders.
6) Can I export results without retyping them?
Yes. After you submit the form, use Download CSV for spreadsheets or Download PDF for a shareable summary. If you change inputs, submit again to refresh the exported results.