EVACUATION OF VACUUM MACHINE

It is important to check the vacuum assist unit on a regular basis. If the vacuum release is too slow, the metal will not fill the cavity completely,. The cracks usually appear on the sides, shoulders and tops. The cracks will be clean with jagged edges. it is important to clean the vacuum machine regularly. Investment powder may build-up on piping and vent holes, restricting the release. To test machine, build-up vacuum pressure, without flask, to 28-30 lbs. Release pedal and note how quickly vacuum falls. It should fall very quickly. If it falls slowly, an obstruction may be occurring. Usually a cavity that does not fill completely is a sign of poor vacuum pressure usually caused by leaking gaskets or poor seals. A slightly plugged vacuum will usually fill all cavities, so regular maintenance is very important.