Awards & Engraving

November '17

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48 • A&E NOVEMBER 2017 ETCH MASTERS before the full light comes on. Often this delay is visible by a brief flickering of the light before it goes steady. As you keep working with the unit, it may turn into quite a few seconds before the light comes on steady. This is a problem, because it will change your expo- sure times and may mean a bad exposure of your material. You may be able to adjust your exposure times for this situation, but eventually you are better off replacing the ballast in the unit. Another thing that most are not aware of is the fact that the bulb will lose its intensity over time. If you pay close attention to your exposures, you might notice that you are not getting the same clear results. Upon noticing that, you need to adjust your exposure time to compensate for that loss of intensity. Again, if you do not wish to monkey around with that, it is best to replace the bulb. Lastly, the bulb will at some time quit working, which is the definite time to replace it. THE TIMER Having worked with many of these expo- sure units over the past 30 years, it quickly became evident that the attached timer on the unit is not a scientific instrument. You can have several of these units side by side and turn them all to the two-minute setting for a test, and you will get as many different times as you have units. My first piece of advice to anyone pur- chasing this unit is to turn the timer to two minutes and check by watching a clock to establish what the actual time is that you get at this setting. This will tell you how accurate, or inaccurate, this device is. If you do not want to deal with the guessing, you best not use that timer at all, but plug the exposure unit into a digital timer to get accurate readings. This is probably your best bet to get consis- tent results, especially because we are usually looking for short exposure times, for which this unit really does not have any settings. One of the resists I often use requires only 20 seconds to be exposed properly. You can play with establishing the right time without having your bulb come on because the timer is a mechanical timer with a spring, which you can turn on and it will run the set time down even though the unit is not plugged in. I have learned to listen to the clicking of the timer and can tell with my unit that three clicks equal 20 seconds. The one thing you want to avoid is cranking your timer up way past the neces- sary times and then turning the knob back- wards when the desired time is reached; you will break the spring. The better way to solve that situation is to have the power cord plugged into a plug strip with a switch, and then turn the switch off once the correct exposure time is reached. The mechanical timer will continue to wind down, but no harm is done to the unit. A common problem with the blanket: the plastic bars break in the middle through continued use. A simple fix while waiting for a new blanket: a splint for the plastic bar. In our dry climate we often have to deal with dry rot, which makes the blanket develop holes, which in turn can affect any exposure.

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