Lapping and polishing are processes designed to remove material from a work piece to achieve a desirable surface finish, dimension, shape or combination of these characteristics. The similarities between lapping and polishing are in the fact that they both use an abrasive in an oil or water based carrier, a vehicle to carry the compound to the work piece and the removal of material from the work piece to achieve the desired finish. The main difference between lapping and polishing is the amount of material being removed and the final appearance of the work piece. Lapping can remove much more material and leaves a dull matte finish, while polishing removes a small amount of material and leaves a bright, reflective finish.
We will only touch briefly on the polishing aspect of this blog. We manufacture Timesaver Lapping Compounds, a non-imbedding lapping compound that breaks down as you perform your lapping activity. While the surface finish achieved can be identical to polishing in regards to the roughness of the lapped surface, the appearance will still be the matte finish of lapping versus the reflective surface of polishing. Polishing is beneficial for the following purposes:
- Cosmetic purposes
- Enhance sealing properties of components in high pressure gas and liquid systems
- Achieve reflective finish
- Measuring for optical flatness
When most people think of the lapping process, they think of production lapping on large rotating lapping plates to produce a desired finish and flatness. For us and our Timesaver Lapping Compounds, it is more of an in-situ process, lapping a specific component for fitment, i.e. a bearing to a shaft, mating gears, valve to a seat, etc. Because the Timesaver Lapping Compounds are non-imbedding and breakdown relatively quickly, they are not recommended for use in production lapping equipment. But, for the same reasons, they are an excellent option in the following instances:
- Assembled gear boxes
- Fitment of bearings to shafts
- Relieving metal build up in a “Hot Bearing” situation
- Resurfacing large elevator and mining gears
The choice of lapping or polishing will be completely determined by your application. If you have a situation where in-situ, non-imbedding or complicated piece work is required, please consider Timesaver Lapping compound. More information can be found on our website, www.ws2coating.com.