Earlier in the year I built this massive miter saw station. The dust collection for the miter saw itself was very functional and worked. I would notice when cutting larger panels that quite a bit of dust would not be captured and would end up on the surface.

Current Dust Collection

Currently I have a 6″ metal duct that runs down below the surface of the saw. Then it transitions to a 6″ flex duct and get attached to the bottom of the dust hood. The below picture shows the general path before the dust hood was put onto it. The interface point is on the rear left of the hood.

Like I said, the current dust collection is useful and pretty good when the saw is fully retracted into the dust box. Once the slide starts to slide out it loses it effectiveness since the dust is moving farther away from the source of suction. The Bosch saw I have (Bosch GCM12SD) does come equipped with a way to colllect dust at the blade. So I figured I would give that a shot.

Updated Dust Collection Attempt 1

My initial plan was to use a WYE at the end of the 6″ metal duct and send one branch to the existing dust hood connection. The other branch would run up to the dust collection near the saw blade. So, I mocked this up on the bench and figured I would test out the airflow capability before permanently attaching anything. The flex hose going to the reduce would eventually go to the saw blade. The branch with the 4 to 6 “increaser” would go to the hood. So, I plugged it into the existing dust collection duct and turned on the system.

Unfortunately, the amount of airflow moving though the small diameter hose was not going to be effective at all. I suppose I could have installed a blast gate on the branch going to the dust hood. Therefore restricting it to try and drive more flow to the blade, but I figured this was a net loss in air flow and had another plan in mind. Another option would be to purchase a 6″ WYE instead of the 4″ I had sitting around, but with the small line size going to the saw blade, I didn’t think it would make a huge difference.

Working on this dust collection after the cabinet was installed was huge fun. I am not sure what my hand is doing (W for woodworking). You can see the existing duct on the right and the dust hood interface on the left.

Updated Dust Collection Attempt 2

Since the dust collection on the saw had pretty small passages, I figured a shop vac (high static pressure) would be a better option. So, I scratched the WYE and hooked up the 6″ hose back to the dust hood. Then I started to figure out how I could get my shop vac connected. Well lucky for me there is about a 12″ gap between the wall and the back of my miter saw cabinets. So I started laying out some 2 1/2″ plastic ducting and flex hose.

Here is the final path (in pictures). First this hose exits my shop vac and it can either be plugged into the boom arm or my miter saw.

This is on the far right of my miter saw station and is currently missing the rubber plumbing connection that allows a quick interface to the shop vac.

It is still missing the rubber sleeve, but here it is mocked up. You can see it goes into a plastic tube, then transitions to a flex hose to make the 90 degree corner to go behind the cabinets.

Then it transitions back to plastic ducting for the long straight path behind the saw. (The right side of the picture is going towards the shop vac)

Next it transitions to some flex hose to get around the 6″ hose and connects to the bottom of the dust hood.

Here is the top side of the dust hood where I have a tool adapter thingy that has been cut to size and mounted to the dust hood.

The final run is some 1 1/4′ hose and a few plumbing connectors

I had to purchase the little plastic piece that is between the rubber plumbing sleeve and the saw. It is model number VAC024 from Bosch, but I bough it on Amazon.

Once this was connected, I could try it out. The air flow was surprisingly loud near the saw as it goes through the plastic ducting on the saw itself. Overall it was really providing some great suction right behind the blade, so I was happy.

Finishing Touches

In order for the shop vac to turn on when the miter was fired up, I had to purchase an IVAC Pro Tools Plus. This device senses current in the power cord of the miter saw and signals the shop vac to turn on. Then I had to trim some of dust wings to allow the 1 1/4″ hose to freely exit the dust hood as the saw is pulled out. I have been happy with the increased dust collection, even though I forget to attach the shop vac hose from time to time.