Inside diameter coatings

Inside diameter work is spray in a hole you cannot stand beside. Extension guns, rotation, and a lot of fixturing turn a worn bore into a coated bore that can be honed or ground back to a fit.

Pump bowls, hydraulic cylinders, and compressor housings arrive with grooves you could hide a pencil in. A new casting is a long wait. HVOF or arc on the ID, then machine, is often the cheaper year. Power plants send this pattern constantly — see power generation. The August shop note on the news page is about taking longer bowls without a circus; that is this cell growing up.

Line of sight still rules. If the gun cannot see the wall at a sane standoff, the coating will be thin on one side and heavy on the other. Drawings that hide a step or a port need a conversation before powder hits. Stripping an old ID coating without wrecking the substrate is its own skill. Inspection may include a bore scope, the same habit listed on Our Company.

ID coatings are not a miniature OD. Heat goes into a shell that can oval. Interpass pauses are in the procedure for a reason. After spray, the finish might be hone, grind, or a combination; the print decides. Related OD work is next door, and the family of guns is on what thermal spray is.

From the home page this is easy to skip. Skipped ID jobs become emergency purchases. Send bore diameter, length, and a photo down the hole. If you have a mating piston, say so. Quality will still want thickness checks where a probe can reach.

Seeing the wall

Bore length, steps, ports, and whether a piston still exists decide the fixture. A photo looking down the hole with a scale beats three paragraphs of optimism. Oval bowls from heat need a conversation about how much roundness you will accept after coating and hone. If the gun cannot see, we will say no instead of coating a banana. Waterjet of an old ID land is often the first day, not the last. Thickness probes only work where they fit; the traveler should admit the blind spots. Power plant bowls and compressor housings are welcome; mystery geometries with no drawing are a delay, not a challenge coin.