overhead/overarm blade guard dust collection

[kayak]

Can anyone point me to research on the best location for the hose port on a blade guard.? I've seen some placed at the rear of the guard, others focused on the front of the blade. I'm trying to decide which way to go.

[Tacuabe]

In our experience the best location is up in front of the blade. This is because while the blade is starting the cut it is buried into the material, therefore any chips or dust are mostly confined within and mostly send downwards. This is also the reason of a second pickup under the blade. Once the cut blade starts its downward travel, the debris is shot forward (against the operator) and the pickup at the front is in the right place to catch them. We use an integral Thien baffle for dust collection.

Bear in mind that no dust collection system is a 100% efficient. In the case of table saws, you'll find that a rip cut so shave just 1 or 2 mm from its witdth will create a lot of dust that the pickup will not be able to collect. This is because the blade is just grazing the workpiece and dust flies everywhere.

You may find interesting a visit to our website www.aw-thinkbold.com. Coincidentally, the first article shown covers the same problem with our blade cover design and free plans to build it. If you're fitting this cover to an American style  of saw, you'll have to devise a suitable way of mounting it. American saws rarely have a riving knife and their blades usually raise following an arched path. Our design incorporates an original system that raises the blade vertically along with the riving knife. For more details it's interesting to have a look of the Reader's projects and, of course, to the videos and pics.

It it possible to add a riving knife to a blade that basculates on a fixed point. I know because I did it in my prototype. However, it's no mean task. If you're interested on how it was done, supply your mail address and I'll send you a white paper on the whole development of the saw with pics on its many parts and the riving knife installation.

Hope this helps!