Tumbling is similar to vibration, except the components and the polishing medium rotate around in the drum instead of vibrating. It is a gentler movement that makes tumbling perfect for the more delicate sections and those with the finest details. The unit used is sometimes referred to as a centrifugal barrel device. The same polishing materials are used for tumbling as vibratory systems—ceramic, rubber, corn cob, and synthetic materials. You can also finish several sections at once, as with vibration. Nevertheless, you need to be vigilant when combining various types of media, as certain combinations cause inconsistency and result in uneven finishing or harm to pieces.

Vapor Smoothing

Vapor smoothing is another method of removing the surface of printed piece, but results in a glossy finish rather than a matte one. This sheen can be removed, however, if desired, with bead blasting or sanding. The vapor smoothing process uses a solvent to melt the surface of your component. After putting the product in a vapor chamber where it is exposed to a solvent, you immediately place it in a cooling chamber to avoid the liquefaction. This cooling ensures that only the surface is melted and the form of the object is preserved.

This method often fills any holes in the exterior of the product and seals the surface, making it especially useful for products intended to hold liquids or gases. Vapor smoothing cannot be used on any form of material, as it can cause harmful chemical reactions in certain materials, including polycarbonate, polyphenylsul- fone (PPSF), ULTEM ЮЮ, and ULTEM 9085. Of course, you will also need a chamber that fits your object, which can be restrictive when printing large components in particular.

Solvent Dipping

The alternative to vapor smoothing is solvent dipping, which, as the name suggests, calls for the part to be dipped into a solvent rather than exposed to a vaporized solvent. This method may be useful if the component is bigger than the size of the vapor chamber.

The findings are very similar to those of vapor smoothing, but it is more difficult to preserve dimensional precision since the solvent works more rapidly and aggressively.

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