Difference Between Lapping And Honing: Metal Surface Finish

What is the difference between the two cutting tool applications and the superfinishing process- Lapping and Honing? What does hone mean? Hone in a definition.

Lapping process

What is Lapping? The main reason for doing lapping operation on the part is to get the surfaces that are genuinely smooth and flat. The part to be processed is first machined close to final dimensions.

Then in the lapping machine, a rough cut is taken which will leave approximately 5μ (microns) of an inch on the surface.
The lapping process is done on a lapping machine. It is an abrasive process. It means bonded abrasives are used in this process as a tool.

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Lapping Machine

Lapping machine includes a rotating 'Lapping Plate' and some conditioning rings.

Lapping Machine

Most of the parts in the Lapping machine are made of high-quality soft cast iron material.

Honing Process

What is Honing? Honing is a controlled grinding. It means it is a low-velocity abrading process. Commonly it is used to finish slots or inner surface of a cylinder.

With honing we can remove as low as 0.1 microns of an inch of material. The main advantage of its overlapping is the rotating table is not required. Thus there will not be any location error.

What does hone mean?

In honing operation tool is generally called as 'Hone'.

True or false?

lapping and honing are processes that create rougher surfaces than grinding or milling. Answer is false.

Difference Between Lapping And Honing

Below is given the summary in tabular form.

SR. NO.	LAPPING	HONING
1.	Final abrasive finishing operation.	Low viscosity abrading process.
2.	Commonly done on outer surfaces.	Commonly done on inner surfaces of cylinders.
3.	It is not a stock removal process.	It is a stock removal process.
4.	The tool is called ‘Lap’	The tool is called ‘Hone’

References (External Links):

• Quora - https://www.quora.com/What-is-difference-between-honing-and-lapping
• A Comparison of Honing and Lapping, Metal cutting corporation - https://metalcutting.com/knowledge-center/comparison-of-honing-lapping/
• Cutting Tool Applications, Chapter 18: Lapping and Honing, American Machinist - https://www.americanmachinist.com/machining-cutting/article/21892103/cutting-tool-applications-chapter-18-lapping-and-honing
• Hubpages - https://hubpages.com/technology/Difference-between-Lapping-and-Honing-process
• Download PDF about the finishing process - http://www.rgcetpdy.ac.in/Notes/MECH/II%20YEAR/MANUFACTURING%20PROCESSES/Unit%204.pdf