Lapping / Honing

Lapping is a specialized process by which metal part surfaces are made as close to perfectly and uniformly flat as possible. Lapping (Loose Abrasive Polishing) can also be used to polish metal surfaces to a fine finish; with certain metals, a mirror finish can be achieved. Petersen Precision was founded as a lapping shop, and we’ve been a leading provider of lapping services since 1966. Honing is very similar to lapping, but is used on the inner surface of a circular or cylindrical part.

Request a quote on lapping or honing for your metal parts, or contact us to learn more about our lapping and honing capabilities.

What is Lapping?

In simplest terms, lapping is the process of making a surface very, very flat. The ideal result is a part surface that is perfectly and uniformly flat across its entire surface.

Lapping involves a large, horizontal, rotating cast-iron plate  onto which multiple, independently rotating rings are placed. Workpieces are placed within these rings, with a thin layer of slurry consisting of oil and a cutting As the larger plate turns, the parts remain in place inside the rings, creating a double-rotating action on the very-fine abrasive slurry.

The pressure on the parts and the duration of the process can be finely-tuned to accommodate for the part material and the final finish required. Under perfect conditions, parts can be lapped to within 10 to 20 millionths of an inch flatness.

Harder materials can be lapped to better flatness than softer materials. Similarly, harder materials can be polished to a higher finish than softer ones; only very hard materials can be lap polished to a true mirror finish.

50+ Years’ of Precision Lapping Expertise

Petersen Precision was built on lapping, and we’re one of the best and most skilled providers of this service anywhere in the world. We utilize highly effective lapping equipment that has been modified and perfected over the years to run more consistently and efficiently than most “high performance” lapping systems on the market. Our customized lapping equipment is also less expensive to operate, which translates to cost savings on your project.

With our experience and expertise, we can consistently lap parts to within ±0.0001” to ±0.0002” of flatness across a several inch span (that is, parts several inches wide).

Petersen Precision’s Double-Sided Lapping Process

In addition to the “traditional” lapping process described above, we also offer double-sided lapping. Operating on the same principal as lapping, double-sided lapping works both sides of the part at once, and, instead of a loose abrasive, uses a bonded abrasive plate. Our double-sided lapping machinery allows for much finer of thickness and parallelism of our customers parts.The double-sided nature of this process makes it possible to achieve parallel flatness on both sides of a part. Rather than lapping one side of the part, then flipping it over to lap the other side, both sides are worked simultaneously to create high parallelism.

What is Honing?

Honing is a part finishing method that is very, very similar to lapping, but that is performed specifically on the inside diameter (I.D.) of round or cylindrical parts, or on blind- or through-holes in parts. It uses more or less the same process as lapping, and can smooth and true an I.D. to tolerances of better than ±0.0002”.

Trust the Long-Time Lapping Experts

We’ve been perfecting our lapping and honing processes for more than half a century. Customers from far and wide, and in all markets, turn to Petersen Precision for precision lapping and honing services. Request a quote today, or contact us to discuss your project.