Mon 17 Aug, 2009
Tags: Shop, Tools, Woodworking
A wood shop is not a static object. It has a life of its own and it evolves just like a living organism. Fortunately, though its evolution can be slow, as mine has been, it also tends to change dramatically in one’s lifetime. Mine has taken eight years to evolve from a completed two story empty building to the shop I will discuss today.
This latest evolutionary step is a big one. It was originally planned to be completed before I even moved in; and it’s one I would not have completed even now if it weren’t for the help of my older brother Ron.
Each year my family has a reunion which occurs on the first weekend in August (I am one of twelve siblings). People come from all over the country to attend and often stay for a week to a month; they visit family, old friends and high school classmates. Ron and my sister-in-law Wanda come from Tennessee and usually stay with me for at least a few weeks. Typical of my family we don’t sit around watching TV and chatting. We have to do something. This year Ron and I decided to add dust collection to my shop.
During the eight years I have been planning this project I read every article I could get my hands on concerning dust collection issues. I was appropriately frightened by articles on the potential for static electricity fires if non-conducting piping were used. I read an article written by an MIT professor debunking that myth. I have no less than five books on building your own shop and/or dust collection system in my library. I debated flexible hose, metal piping, plastic piping with grounding wire and PVC. It wasn’t until my oldest brother Clark piped his basement shop with PVC recently that I settled on it as the pipe of choice. I must admit here and now, my extensive research played a minor role in my decision, which was based primarily on my brother’s choice, PVC’s availability, its relative inexpensive cost and the MIT professor’s article (I’m an electrical engineer and it made sense to me).
At this point the project is not complete. I need to add fourteen 4” blast gates, all the manual plastic variety, and flexible hose connecting the shop’s equipment. I also left a 3” drop near the Lie-Nielsen Workbench providing a vacuum system for my Random Orbital Sanders (ROS). The current state of this project is shown below. My Powermatic Dust Collector has three 4” ports. Two of them are used to connect to the two returns shown. Not shown is the third port which will connect directly to my 8” Jointer with hose only, no piping. We also made provisions for a future second floor line. Click on the picture below to enlarge it.
The project used approximately 100’ of 4” PVC and numerous wye’s and 45 degree fittings plus a few 4” to 3” fittings – all schedule 40. In addition I will use 14 4” blast gates. All told it cost me $615.14. I chose to buy the PVC pipe and fittings at a local plumbing supply because they had all the fittings, J hooks and ceiling hooks I needed. Home Depot had all but the ceiling hooks. To my surprise the plumbing supply charged $1.60 per foot of PVC while Home Depot charged $1.13, a difference of $47. The fittings were also less expensive at Home Depot so I spent about $100 more than I should have.
My brother Clark discovered that standard black plastic 4” blast gates used in many shops fit snugly inside schedule 40 PVC. All that is needed to secure them is two sheet metal screws and silicone sealer. I used PVC cement on all the piping and fittings because I am unlikely to make many changes. However, the blast gates may change in the future should I decide to use switching gates or add a wye to the drop for expansion. Removing two sheet metal screws and sealer is easy compared to sawing off cemented pipe.
Note the picture on the left shows a 4” to 3” reducer and drop. This will be used to connect to a vacuum hose with the other end connected to a Random Orbital Sander. I will need to add further reduction to match my two sizes of ROS hoses.
One thing my research convinced me of is loss due to 90 degree fittings. Ron and I chose to use two 45 degree fittings and a 6” connecting piece in lieu of a long sweep fitting to achieve the same effect (in some places a wye, 45 degree fitting and 6” connecting piece was used). Forty-five’s are more readily available and more flexible – the design changed numerous times during the project and this flexibility was very much welcomed. One significant change was to put most of the piping on one leg, leaving a second for future second floor expansion. The third leg is also lightly loaded; only the router and table saw are on it. I may expand this leg to provide more shop vacuum capability.
Supporting this much PVC required both J Hook’s and Ceiling Hangers shown above right and left respectively. This allowed us to hang the PVC 5” on pipe center to the ceiling everywhere along the run. The piping, done this way, does not interfere with the fluorescent lighting. That is, it blocks no light and casts no shadows. I will complete this post when I have added the blast gates and hookups. Hopefully I will be able to report a positive experience using dust collection. Stay tuned.