Bare with me while I work to expand this section, but I can tell you in a sentence that aging wood is pretty easy with UV lamps. It reminds me of Ron Popeil's Ronco/Showtime Rotisserie commercials where he yells "Just set it, and forget it!". In most respects, it is that easy. The big variable is "how long".
Any of our 4 foot lamps will work for aging, but they do different things. The Universal UV is the best seller for aging because it has a high amount of UVB, not just UVA. Think of it as a clear day, on the equator, in July, then double the amount of UVB. Of course, most of the output is still UVA, which does most of the heavy lifting, the UVB just adds a little "harshness" to the color, in a good way. Makes it look authentic instead of mechanically aged, and that is part of separates our lamps from others.
Our 4 foot lamps fit any fixture designed for office style lamps (32w) or even those for the 1.5" diameter shop lights (40w). They will operate just fine at these wattages, and if you aren't in a hurry, there isn't a need to upgrade. If you do a fair amount of aging, or if you are always fighting time, then you want to upgrade to a more powerful ballast. Our Workhorse 7 ballast is fairly cheap and powers the lamps at around 45-46 watts, which is the sweet spot for them. We build them specifically for this wattage, although they will run with as little as 25 watts, or as much as 60 watts. I test each batch at 70 watts, but that is over spec and there really is very little difference in output compared to 60w, but it does cut the life dramatically. The more watts you give them, the shorter their life. This is why 45w is perfect, as the life is slightly shorter than if you use 32w, but the power from them is closer to 40% higher. Definitely the sweet spot.
Running at 45 watts means the lamps get hotter, mainly at the ends. All UV lamps are weakest towards the ends anyway, and strongest in the 3 foot center section. For most applications this isn't a big deal but if you are working with veneers the extra heat can dry or curl them, so provide ventilation if you are getting close to the material.
The same basic rules for all applications apply here, if you want to be 3 inches from the material, the lamps need to be spaced 3 inches OR CLOSER, measured center to center of lamps. Going from 3 inches to 6 doesn't cut the power in half, it cuts it much more, as the power drops off exponentially with distance, not in a linear fashion. For aging, lamp spacing is important, more important that for any other use of UV lamps. If you judge the numbers and use too few lamps, you WILL have striped wood. You hurt nothing by using too many lamps, but too few will ruin your project. If you are on an absolute budget and just can't afford a bunch of lamps, you have no choice but to pull the lamps away from the project and just expose 2 to 4 times longer.
Once a day, you must re-position your project, or the lamp fixture. This is because the lamps are strongest right in front of them. Even with proper lamp spacing, it is a good habit to move the project once or twice a day, depending on how long you are exposing. If you are running an extra tight pattern, say the lamps are 3" from center to center but you are staying 6" away, twice the distance, then moving the project or light is unnecessary, as there is ample overlap. You have to visualize this in your head, our eyes can't see UV or differentiate the differences in brightness at this scale, but it will show up in the wood if you don't consider this.
|Comparison of lamps|
||Most popular for aging. Moderately fast, has twice the UVB as natural sunlight, wide-band design covers must of the UV spectrum, imparts excellent color to the wood. Gives results similar to natural, outdoor sunlight. Built in reflector inside the bulb.|
||Opposite of the Universal, this is a narrow-band design centered around 365nm, which is the same peak the sun has in the UVA spectrum. This lamp will give results similar to filtered UV, such as you would get with sunlight coming through windows. (windows filter all the UVB and some of the UVA, so fading indoors is from UVA only). Softer results, moderately fast. Not better or worse, just different. Built in reflector inside the bulb.|
||6', 4' and 20" sizes avail.
||80-120w, 40-80w, 15-30w respectively
||Exceptional lamp in every way. Twice the output per foot. Requires building your own rig, but is best for commercial applications. Extremely high output around 370-375nm, plus two UVB ranges in 280-290nm and 310-315nm. Patented lamp, the only one to reach the high octane ranges in the 280nm range. Designed for 100w, but will operate anywhere between 80w and 120w. It will handle higher wattages, but will have drastically shorter lamp life. These lamps typically last twice as long as our 4 foot lamps, or any other 6 foot lamp due to the patented design, so it is very common to get 2000+ hours out of the lamps. Built in reflector inside the bulb. Uses same bi-pin lamp holder as the 4 foot lamps.|
This image is a fair example, even if a bit simplistic. This board has a very thin finish (UV cured, in fact). The center section has no UV aging, the right has about one day, the left has about two days. Not the best photography, but you can still see the character in this example, which was nothing but a 1x3x8 piece of rough pine, unsanded, and bought at Lowes for a couple of dollars. Even with just two days, you see golden color and the grain beginning to pop. Every wood species and board will be a little different, that is just the nature of trees, quite literally.