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How to Use a Surface Grinder
Guide · Updated October 28, 2026
A surface grinder takes very small cuts to make parts flat, parallel and to size within tenths. Most of the skill is in setup: a clean chuck, a dressed wheel and light, patient passes.
Grind to a tenth
Measure with a mic checked against gage blocks, or compare on a surface plate. Check it with a mic you've verified against gage blocks; the free Gage Block Calculator builds the stack.
Step by step
- Check the wheel: Ring-test a vitrified wheel and make sure it suits the material and the speed rating.
- Dress it: Dress the wheel with a diamond before grinding.
- Hold the part: Clean the chuck and part, place the part across the poles, block it and switch the chuck on.
- Touch off: Lower the wheel until it just sparks on the high spot.
- Rough: Take about 0.001 in downfeed per pass with crossfeed about 1/4 to 1/3 of the wheel width.
- Finish: Redress if needed, then finish with 0.0002–0.0005 in passes and a spark-out pass.
- Flip and measure: Demag, deburr, flip and grind the second side, measuring as you approach size.
Worked example
Grinding a 0.506 in steel block to 0.500 in: grind side A at 0.001 in per pass until it cleans up, taking about 0.003 in. Flip, grind side B at 0.001 in until the mic reads 0.5015 in, redress, then take two 0.0005 in passes and a spark-out pass. Final: 0.5001 in, parallel within 0.0001 in.
Burns and chatter
Burn marks mean a loaded or too-hard wheel, too much downfeed or no coolant. Dress, lighten the cut or try a softer, more open wheel. Chatter is usually an out-of-balance wheel or worn spindle.
Taper and dishing
If a part is thicker at one end, the chuck may be out of flat or a chip is under the part. Clean everything, and grind the chuck only if it needs it.
Tips
- Dressing: dressing a grinding wheel.
- Holding: magnetic chuck basics.
- Speeds: grinding speeds and feeds.
- Finish: surface finish basics.
FAQ
How much downfeed on a surface grinder?
About 0.001 in roughing and 0.0002–0.0005 in finishing per pass.
What wheel for a surface grinder?
A white aluminum oxide wheel around 46–60 grit, medium hardness, is a common general-purpose choice for steel.
Why is my part burning?
The wheel is loaded or too hard, the cut is too heavy, or there is no coolant.
How do I grind a part parallel?
Clean the chuck, grind one side, flip and grind the other with light passes.
Can you surface grind aluminum?
Yes, but it loads wheels; use an open wheel, coolant and dress often.
Related guides and calculators
- How to Dress a Grinding Wheel
- Magnetic Chuck Basics
- Grinding Speeds and Feeds
- Surface Finish Basics
- Flatness and Parallelism Checks with Gage Blocks
- How to Use an Angle Plate
- How to Use a Spin Indexer
- How to Use a Tool Post Grinder
- How to Balance a Grinding Wheel
- How to Use a Surface Roughness Tester
- How to Use a Compound Sine Plate
- How to Use a Toolmaker's Vise
- How to Use a Magnetic Sine Chuck
- All free machinist calculators
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