Sawdust on the Floor

I saw a tee shirt at one of the woodworking stores, that was inscribed, “How to tell if you’re a woodworker”. One of the items on the list, was something to the effect of ” If you blow your nose, and sawdust comes out……..then you may be a woodworker”. At first I thought man that’s funny, then my adult brain kicked in, and I realized that this was a serious issue.

If you are one of the fortunate few who live in an area where you can work with the doors and windows of the shop open year round, air filtration may not be a large issue. Unfortunately, most of us live in areas where this is not possible, we have to be concerned about the possible air contamination in our shops.

Several manufacturers offer solutions for the woodworker. One system is the Jet dust collection system, and the other is the Jet air filtration system. Dust collection systems work somewhat like the standard shop vacuum, but with much better air filtration. The dust collector can be connected to machines like the tablesaw, jointer, router table, shaper or thickness planer with a 4″ flexible hose. Basic dust collection systems consist of very few actual parts, the motor and vacuum assembly, and two removable bags. These bags are normally mounted vertically, one on top of the other with the open ends of each meeting in the center. The lower bag will collect the saw dust particles, while the upper bag filters the air before it returns to the shop. Larger, more expensive units may have a series of collection and filtration bags, these units also will have larger motor and vacuum assemblies.

Some woodworkers move the hose from the collection system between machines as they are used, while others favor a more permanent arrangement. These installations may have a combination of rigid tubing and flexible hoses connecting various machines and the dust collection unit. The tubing can be either plastic pipe, or metal 4″ pipes. Most of the smaller system, do not have a large enough motor to apply vacuum to several devices at the same time, so shut off valves are installed at each machine. As each machine is used, the operator opens the valve, also known as a blast gate for that machine, and closes the one for the machines not being used at that time.

When tubing is used, it is advisable to use “wye” connections, and not “tee” connections. There is too much resistance to flow in to the “tee’s”. The “wye” must be installed with the flow toward the collection unit. It is also advisable to run a bare copper wire inside the tubing and connect it to all of the machines connected to the dust collection unit. The flow of the saw dust through the tubing and hoses can create a static build up, which can result in the operator receiving an electrical shock, or static sensitive tools can be damaged. The bare wire acts to put all of the tools at the same electrical potential, which reduces the potential for a shock.

There are maintenance items for the dust collection system. Some of the units have cloth bags, which do not allow the operator to see just how full the collection bags are. When the collection bag get too full, the collection system does little more then make a lot of noise. The other issue is that the bag that filters the return air, are also made of some cloth material and these bags need to be cleaned regularly to maintain the effectiveness of the unit.

While dust collection units are normally mounted on the floor of the shop and collect the majority of the saw dust chips, the air filtration systems are normally mounted on the ceiling of the shop and work to eliminate to smaller airborne contaminates from the air in the shop.

Air filtration systems re cycle the air in the shop, removing particles down to the micron level. The actual filtration levels vary between different manufacturers and models. Also the filter media may differ between manufacturers. Maintenance on the air filtration units consists of either cleaning or replacing the filter media on a regular basis.

Air filtration systems normally are ran for the entire time that the shop is occupied, rather then being cycled on and off as the dust collections tend to be. One of the nicer features of the air filtration systems is that the unit can be set to run for a specific amount of time and the shut off. This is really nice when you want to keep the airborne contaminates count low, such as when your finish coat is drying. Before you leave the shop, you set the timer to run for say 4 hours, at which time the air filtration system shuts off. And your finish has been protected from any airborne dust particles.

To get the most effect air quality in your shop, both the dust collection systems and the air filtration systems should be installed and used religiously. Both are important tools to help keep you healthy while in the woodworking shop.