Miter saw dust collection ideas?

[Jason White]

Well, after years of owning a Festool KAPEX miter saw (which had amazing dust collection), I've sold it and am now using a new Bosch 12" slider. It's an excellent saw, but the dust collection sucks. And not in a good way.

This particular saw allows me to push it tight against a wall because it doesn't have slider arms in the back. I'm planning to build it into a dedicated miter bench. Any suggestions for catching the majority of the dust that gets blown behind the saw? I'm thinking about building a plywood box and connecting it to my big dust collector, unless you folks have better ideas.

Thanks for any help!

Jason

[Peter Aeschliman]

A plywood box is your best bet. The most important thing in my opinion is to make the pickup area pretty big. So if you have a 6" duct, break it up into three 4" pipes that pick up dust in three different areas behind the saw.

This is because the dust expands into a big cloud behind the saw, and because you will sometimes make miter cuts.

Even better would be to figure out a way to enclose the box enough that there is negative pressure inside of it. This way, even if the fine dust doesn't spray directly into your duct, it will eventually get sucked up before escaping into the shop.

I've seen people use hinged or movable panels, or bristles like from a broom. I think there's a company that makes a product called "saw stache" or saw mustache or something like that.

[Steve Peterson]

A plywood box is your best bet. The most important thing in my opinion is to make the pickup area pretty big. So if you have a 6" duct, break it up into three 4" pipes that pick up dust in three different areas behind the saw.

This is because the dust expands into a big cloud behind the saw, and because you will sometimes make miter cuts.

Even better would be to figure out a way to enclose the box enough that there is negative pressure inside of it. This way, even if the fine dust doesn't spray directly into your duct, it will eventually get sucked up before escaping into the shop.

I've seen people use hinged or movable panels, or bristles like from a broom. I think there's a company that makes a product called "saw stache" or saw mustache or something like that.

That is what I do for my Bosch glide. I have a plywood box that sticks out about 6 inches. The saw is on a sliding board so I can pull it further from the wall for bevel cuts. I have a 6" dust collection system that branches into 3 X 3.5" holes behind the saw and a 2.5" duct to the sawblade. The 3.5" hole is the largest size hole cutter that I own. 3 holes is about the same cross section as the 6" main pipe. It probably catches about 80% of the dust.

It would probably take a flexible fabric shroud mounted to the saw head to catch the rest of the dust.

Steve

[Charles Taylor]

I've got a DeWalt CMS, and I'm on my second iteration of the plywood box idea. The first iteration was a box with a 4" hose at the top. That didn't work, because only the finest dust stays airborne long enough to get caught up in the weak air flow going out the hose. The rest of the dust settles behind, beside, and underneath the saw.

Second iteration is not perfect but much better. It has a 6" duct at the top. (By this time my whole dust collection system had been upgraded from 4" flexible hose to mostly 6" metal duct.) A small flexible hose attaches to the dust collection chute on the saw itself and goes through the top of the box and into the duct. The box has a false back, separated by about an inch from the back of the box, and with an opening at the bottom about an inch high. At the top of the box the false back allows air flow into the duct. Dust eventually tends to settle at the bottom of the box, and most of it gets caught up in the flow going up behind the false back.

I have movable panels on the front of the box that will close as tightly as possible around the saw in its normal position and open up to accommodate the saw's movement when set at other angles. They work pretty well to contain the dust cloud until it settles and is (mostly) taken up through the opening at the bottom rear of the box.

[Don Kondra]

This is a build I did a few years ago....

http://www.sawmillcreek.org/showthre...ion-for-a-SCMS

Cheers, Don

[Ben Rivel]

Why did you get rid of the Kapex? Its rails dont stick out of the back. Is the back clearance really that much less on the Bosch Glide?

[Martin Wasner]

Two things that I would do differently from what is in these two pictures.

-Make the hole behind the saw larger. Like as wide as the box. The tapered part of the sides doesn't do much good. Stuff still builds up quickly.
-The other is to add a pair of vertical strips in the back wall of the box. It does a relatively good job of keeping the sawdust that sprays against the back wall somewhat contained. I have those strips on there now, and it dramatically improved how much stuff goes straight down.

It's not in either of the pictures, but I cut a hole in the basin and there's a 4" pipe connected to the dust collector.


Dust collection on a miter saw is typically mediocre at best. Make gravity work for you as much as possible. The fine stuff is pretty easy to keep under control as long as there is some negative pressure at work. The course stuff is just dealt with by directing it as much as possible to the port.

[Rollie Kelly]

I have noticed that all most everyone uses a hard right angle at the transition between table top and the duct work. A moving fluid, air in this case, doesn't like right angles. There are very few right angles on an airplane. Rounding over the transition point, the larger the radius the better, will increase the velocity and improve the quality of the air flow.
Concentrate on improved air flow and the dust will follow.
Rollie

[Greg R Bradley]

Why did you get rid of the Kapex? Its rails dont stick out of the back. Is the back clearance really that much less on the Bosch Glide?

Bosch Glide gains nothing on a Kapex for getting close to the wall. They are basically identical at 15-16" from the fence to the back of the saw depending on how you hook up dust collection. There are a few non sliders that can get that down to 12". It seems they all could do a lot better if that was more important during the design process.

[Mike Henderson]

The problem with the Kapex is that it's a 10" blade which limits your depth of cut. I bet he bought the Bosch 12" to get more depth of cut.

I had a Bosch 12" and then bought the Kapex. The Kapex is a good saw but the biggest problem is the limited depth of cut.

Mike

[I bought the Kapex to get more width of cut, which it does because it's a slider, but lost depth of cut. The Bosch may solve that problem - good width and depth of cut.]

[Jason White]

Exactly why I sold the Kapex. Wonderful machine, but it was just too small for my needs. I sure miss it, though.

[Deb Clarkson]

I put together 2 plastic window well covers to make a shell behind the saw, then connected a 4" fitting for my dc hose. I added flaps the could hang across parts of the front and be moved as needed for miter cuts. Still wasn't real happy with the amount of dust that floated into my lungs (I hate wearing dust masks). I finally bought a clear shower curtain and drape it over the whole thing while I make a cut. Works great.

[Jim Dwight]

I don't have a slider, I use a 12 inch Hitachi and a RAS. I wanted to improve the dust collection for the Hitachi and bought the dust chute of a Kapex. I think it was $25. I had to modify it and the saw to get them to mate up but it works now and improved the amount of dust that goes into the hose for the shop vac. I haven't studied the design of the glide but if you could get a Kapex chute on it, I think it will help. That isn't all that was done right on the Kapex but it is a significant part of why it works like it does.

[Chris Parks]

I have the answer for the Bosch Glide Saw but forum rules prevent me linking to the thread I put on another forum but SMC would not object if I had put the thread here and then linked that to every other forum on the net. If I PM the link then I prevent any other Bosch Glide saw user seeing the information as well so that seems pointless.

Edit: To see Chris' post, go to woodworkforums dot com and search on "dust hood for bosch glide saw" You will need to register there in order to see the pictures.

[Jebediah Eckert]

^^^ Can't you just give a search term to plug in to get it to come up? I tried every which way and could not find it. You have a definitive answer that could be "shop changing" for Bosch Glide owners.

Thanks