Last month I installed a central dust collection system using components manufactured by Air Handling Systems of Woodbridge CT. In this review I would like to offer an overview of the components themselves as well as some suggestions that would help another first time installer avoid some possible pitfalls and errors. A complete review of the dust collector itself, a Felder-Austria AF-22 will be done in another article.
The components of the system are the spiral pipe and the various fittings, i.e. lateral tees, elbows, reducers, blast gates, etc. The spiral pipe is made from mostly 22g galvanized steel , while the fittings are of a heavier 20g or greater galvanized steel. All fittings, tees, elbows, etc. are welded , thus limiting the amount of caulking needing to stop any air leakage. All the components are very well made. I was surprised that each component was made to very tight tolerances. The system is designed so that fittings fit very snug inside the pipe. Pipe to pipe connections are made by a special fitting. Fitting to fitting connections are made by cutting of a small piece of pipe. The whole system was shipped by UPS and arrived in very good condition.
PLANNING AND INSTALLATION
I cannot emphasize enough the necessity to properly size and plan your system. Make a scale drawing of your shop showing machine placement and then draw out the individual components both from an overhead and a side view. Recheck your figures several times. I did this and still made a couple of small mistakes. As for sizing, Air Handling has a program on the web site which will help you size and design the system. Also the book, Woodshop Dust Control by Sandor Nagyszalanczy, helped me more than anything else. The book of course can be purchased through the Badger Pond Bookstore.
My system has a 6” main trunk line running down the center of the shop. From that main line I have several 5” and 4” drops to the various machines. A system like this should work fine for most small shops.
I installed the system myself, but if you have some strong friends who owe you a favor now would be the time to call the favor in.
When you receive the ducting system, naturally check the order for shortages. My order perfect.
Before starting have on hand a good hacksaw and blades, a good jigsaw with some fine tooth metal cutting blades, rubber mallet, drill bits for metal, about 200 1/2” self tapping TEK screws, metal file, caulk, pipe strapping to support the duct overhead while you are fitting it.
Because I had to locate the dust collector itself in a certain location and also that the machines were in place, I started from the dust collector and worked from there. You may find another way more preferable. If you can put together on the floor as much duct as you thing you can handle. If you are working by yourself, it won’t be much as this stuff is heavy.
To provide adequate clearance I planned my system so that the duct is suspended about 8” from the ceiling. The are a couple of ways of doing this. I used a U-channel (found at electrical supply houses) with spring nuts to which I attached 1/4” threaded rod. To the threaded rod I attached the duct via the duct hangers. I found that the U-channel cut long enough, allows you to make adjustments in straightness of the run of duct. The threaded rod allows for easier leveling. To attach the pipe and fittings together I mostly used 1/2” TEK screws. I also used some rivets, but didn’t like them that much. I caulked each fitting, to completely seal it. I found that a good clear caulk looks and works fine. Once the main line is installed, then the smaller drops either directly overhead or along a wall are relatively easy to install. You will need a blastgate at each drop. If you are going to attach a flex hose directly from the blastgate, Air Handling has a special blastgate to hose connector that makes the connection easy and fast.
ORDERING AND CUSTOMER SERVICE
You can order the system direct from Air Handling or you can order from their dealer network. The price should be about the same. I like to support local companies so I ordered mine from Carl LaBarca at Delaware Valley Woodworking in Wilmington DE. They processed the order quickly and had it delivered to their shop in about a week. Ordering locally came in handy when I needed a couple of extra fittings I neglected to order as they had them in stock. When I needed a 5” 45degree elbow that they didn’t have, I made a quick call to Air Handling. They have great customer service, the needed part was shipped out UPS and I had it the next day.
- Do not order the crimped spiral pipe to make pipe to pipe connections. Without an hydraulic ram or equivalent it will be next to impossible to drive the fitting home. The separate coupling in much easier.
- I found the best deal in quality Urethane heavy duty hose to be from McMaster-Carr. Most places want to sell hose in 25 or 50’ lengths but MC sells it in 5’ increments.
- I used a remote control start/stop system that is available from Lee Valley. They had the best price and offered a unit that could handle 220v/20a. I believe this same system the X-10 is available from Radio Shack.
- The edges of the metal pipe and fixtures can be sharp, so be careful.
If anyone has any questions about anything that I haven’t covered here please feel free to post a question on the forum.
John Renzetti - 6/27/98