Carbon Evaporator Back in Service

The carbon evaporator is now working again. Please contact (Scott 5-5071); or (Glenn 3-5493); if you have any questions about using it. You may sign up for time on the carbon evaporator calendar page.

1) In an effort to keep from continuing to burn out transformers, we request that our users adhere to a policy of coating for no more than 4 minutes at a time and then letting the transformer cool for at least 10 minutes before resuming coating. This is a conservative interpretation of the 40% duty cycle rating of the transformers. 

2) The transformer for the left-side electrode, which we have designated for chromium coating, is set up to coat at lower voltage (12 V) and higher amperage (up to 90 A) than the right-side transformer. We are now providing multi-use Cr-coated W rods that are supposed to evaporate Cr at 78 A. It seems to be necessary to attain more than 78 A to initiate coating, but please try to keep the amperage below 90 A on the new 100-A gauge.

3) The transformer for the right-side electrode is designated for carbon coating as well as gold evaporation. It's set up to coat at 24 V and no more than 45 A. Because our users are often interested in creating relatively thick gold coats, the right side will likely require periodic cooling, as noted above (1).