Hello again, colleagues! Thought I would post an update on the DIY Clean Chamber project I mentioned quite some time ago. I've posted the update on a couple of other forums but one is limited to Dolphin Data Labs customers and the other is rarely involved with data recovery. If it is helpful to others looking for a low-cost [almost] clean room environment, that's great. I say almost, because the filter used is not HEPA certified, even though "The RIDGID 5-Layer replacement allergen filter is made from HEPA-rated material and removes 99.97% of all particles .3 microns and larger from the air." and "Filter made with HEPA-rated material but does not meet EPA or RRP guidelines for certified HEPA filtration."
As posted on the Dolphin Data Labs forum:
Below is a description and pictures of a “clean chamber” I built a few years ago and recently updated. I have copied most of the information that I original posted on another forum (http://pcbusinessguide.com/forums/index.php?topic=85.0
), to keep it all in one article.Original article
(the essence, without pictures):
I thought some of you might be interested in making your own clean chamber, for working on hard drives. There are a number of sites that can guide you on how to change drive heads, but few on how to construct a clean chamber in which to do the work. I built a clean chamber from the following readily available parts:
· tote box (100 quart capacity, I think)
· Rigid brand HEPA VF6000 Wet/Dry Vac filter and matching end plate
· 18x30x1/8" Lexan (should probably have used thicker; Lexan is less likely to crack than acrylic, but is not quite as crystal clear)
· 120mm 115v fan
· 24" piano hinge
· a number of shelf brackets, some of which had to be bent to fit the angle of the lexan, at the top
· misc. bolts and nuts; Goop or Acrylic cement
The critical dimensions were 6" for the top shelf and 5.25" for the bottom lip of the tote box. I marked those points then used a straight edge to draw the cutting line along the ends. The Lexan was cut into a 13x30" piece and glued to the tote with Goop (which works very well, although Acrylic cement probably would be better), then trimmed it to fit more closely. The Lexan bottom piece is 5x30" and has two 4" hole through which to insert one's arms. It's not an air-tight fit, but it doesn't need to be; you need to allow for the air to exit. When not in use, I cover the arm holes with sheets of paper attached with low-tack masking tape. It would be good to find something to secure the lower flap while working on the drive, e.g., tarp fasteners attached to the lip of the tote.
The filter end-plate had its end cut out and the opening was then routed smooth with a dremmel tool, and had a coat of Krylon paint applied to seal the fibers which otherwise contaminate the box. It was glued to a fitting plate with Goop. The plate had a hole cut into it to match the fan opening, and was then bolted to the top of the fan. The filter sits fairly securely in the end plate. The opening in the end of the filter was plugged with a patch of aluminum duct tape. For antistatic protection, a piece of antistatic plastic used to enclose motherboards was fitted and taped into place using the same aluminum tape, and a bolt was fitted to allow clipping of an antistatic strap on the inside, and a ground lead to the outside.
Air flow is fairly restricted by the filter, but it should be sufficient. It is also anything but laminar; it tends to radiate in a hollow cone shape instead of down the back wall or evenly across the box. I considered adding a plenum beneath the fan to distribute airflow more evenly, and adding a second fan and enclosure to the filter, to act as a compressor stage. However, I think that's unnecessary. Handles were added to the ends of the box, to make it easy to move around. Anyway, if this can help someone considering working on the innards of drives, that's great!Recent Enhancement
Since writing that article, I have updated the clean chamber by adding a compressor stage, a second, more powerful fan (http://www.active123.com/CFA11515055HB- ... dview.html
), and deflection plates and perforated screening to re-direct the air flow so it flows from back to front, rather than vertically. I also split the front window, so I can fold the sections up out of the way, to provide unobstructed access to the working area. Pictures of the current chamber follow.
It works well enough, I think, but I am considering changing the fan to a more powerful, 440 CFM model (http://www.ebay.ca/itm/4-6-8-10-12-Inch ... 3a74b89518
) , so I can increase the airflow speed and volume. By blocking off parts of the perforated screening, it increases the airflow to an acceptable level for now. I also need to tidy up the wiring and grounding. If you have any questions, don’t hesitate to ask.