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Jack of too many trades..
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601 Posts
Discussion Starter · #1 · (Edited)
I've been unhappy with the ability to collect dust from the top of my Unisaw for quite a while. I was a bit inspired by photos of WoodNThing's setup, so last year I picked up a boom-arm setup suggested by the guys at Woodcraft, and installed it upside down on the ceiling of my shop.

Here it is as of last week after I modified the nozzle and redirected the vacuum hose based on suggestions in another discussion.
Bicycle tire Wood Bicycle fork Automotive tire Bicycle part

That's a ShopVac nozzle that barely accepts my 2-1/4" hose end.

It worked okay, but I found that the long arm coming in from the side was usually in the way when I tried to make cuts using a pusher tool and stick. The collector nozzle would also "bob-around" a lot. Overall, I felt that it was going to get me hurt at some point and I needed a better solution - something that didn't come in from the side, but instead came down from the ceiling on some sort of armature.

After some investigation, I could not find an armature of the proper length, but I realized that some of the microphone armatures out there are held together with nuts and bolts. So if I bought two cheap units, I could do a little Dr. Frankenstein surgery...

After some delivery delays, I got to work on this project this morning. I ended up combining parts from two armatures into a 3-part arm with tensioning knobs on the "elbows"

I mounted the "socket" to a block in between the joists directly over the top of my saw blade (found with a laser level)

All together, it looks like this:
Automotive tire Wood Bumper Gas Flooring


Up close from the back.
Crankset Tire Bicycle tire Bicycle frame Automotive tire

Now I have a clear path on both sides of the blade - no big arm coming in from the side to get in my way.

If I need to get it out of the way, I can just raise it up (it can go even higher than this)
Automotive tire Wood Bicycle tire Bumper Beam

I can also just turn it to the side when I'm running a window sash over the blade for a weatherstripping groove.

It turns out the super-coarse thread on the armature shaft for the microphone mount is 3/8-16. I drilled a small hole in the top of the hose nozzle and used a nylon nut on the inside. I used some superglue as a threadlocker. Not sure how CA glue performs on nylon plastic, so I'll need to keep an eye on it.

A "nylock" nut might have been better, but it occurred to me that if a metal nut worked loose inside nozzle it could drop down into the blade and become a speeding bullet.

The armature was a little fussy to build and I have to remove some of the tensioning springs. Someone more clever than me could probably work out the most ideal way to assemble all the parts and get the springs and tension working better for such an application.

All-in-all, this set me back $30. $10 each for the armatures, and another $10 for the new vacuum nozzle. I also have some spare arm parts, if I want to experiment further.

These are the arms I bought
 

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where's my table saw?
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31,716 Posts
Very clever use of repurposed mic booms!
What I discovered using the 2" PVC pipe sections is that there's enough friction to hold the blade cover in place without any fasteners.
If I wanted to ceiling mount a blade dust collector, I would take advantage of that property and use a couple of 2" 90's with a short stub section in between them.
I would need to make a sketch of my idea to better illustrate it. But it's very similar to the first version I used here back in 2009.
It worked fine and did a fair job of collecting the dust off the blade, I don't really remember why I stopped using it.
The shop vac is close just hiding under the table saw. My ceilings are slanted so that won't work for me.
Table Wood Automotive design Workbench Tool


This one can be rotated around on it's vertical support post, completely off to the side and out of the way.
The orange dust collector can also be rotated to a vertical position where it just stays be friction alone.
Or, it can be removed entirely just by pulling it off the long horizontal pipe.
 

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Jack of too many trades..
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601 Posts
Discussion Starter · #3 ·
I blame COVID-19. I had to switch to work-from-home mode and after I got a boom mic for my computer setup. I'm using it constantly for meetings and such. It's too short now that I have a dual-monitor setup, but it got me thinking that if it had one more segment, it would reach over my monitors... which led to me revisiting my persistent issue with the TS dust collection setup.

What I like about the vacuum boom so far is that it will fold up almost completely against the ceiling, but with the various adjustment knobs I can position it slightly higher, slightly lower, slightly forward, or slightly rear and pretty much lock it in place. I think this will let me experiment with optimal location for optimal collection for various types of materials and cuts.
 

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Jack of too many trades..
Joined
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601 Posts
Discussion Starter · #6 ·
Well, I did a small reorganization of the shop after I removed my 40" tablesaw extension and took it down to about 20 extra inches. The saw is now closer to the wall so I had to relocate the overhead armature closer - to right in front of the ceiling dust filter. That's a bit awkward, but it does work.

It still works pretty well, and at the moment it's the only active dust collection on the saw. I use it in concert with two clone ceiling air filters and it does a pretty good job. I have the main 4" piping disconnected because of the re-arrangement of the space.
I'm focusing on repairing some structural issues in the house itself and a slow-mo kitchen renovation, so I'm not using the saw very much right now.

I will say that the two problems I've encountered are these:
1) the armature can rotate in two places. That is, it can rotate 360 degrees at the top and at the single spindle for the collection nozzle. The two adjustments have the advantage of allowing me to position the nozzle a bit to either side. Also, to adjust out a small lack of alignment between the ceiling mount and the blade. Unfortunately, it can also get knocked out of alignment a bit too easily and there are no "positive stops". The armature is a tad "spindly." Sometimes this is good, like when the 2" part of the nozzle obstructs the wood that I'm cutting, and other times it's not - like when it fall out of alignment with the blad when I'm making a cut. I think if I were to combine another pair of armatures and mount them as a set of two arms inline, with two ceiling anchors and two point of contact on the nozzle, I think it would be an improvement in terms of stability without sacrificing the small size and ability to fold it up against the ceiling.

2) I lack a long outfeed table... when I rip long piece of wood or ply, they tend to lever up and sometimes hit the nozzle before they clear the end of the deck. One time, it levered the nozzle down into the blade, and the blade took some of the end of the plastic off.

I still think this is superior to my original set up, but there is still room for improvement. When the nozzle is properly aligned with the blade, the dust collection really is quite good. I also still very much like the ability to fold it up and away. That saved me a lot of trouble when I cut dados or rabbets, or something very tall.

What would be good is some sort of heavy-duty "gooseneck" arrangement, where it is strong enough to hold a 2" hose and nozzle, but can still be adjusted and aimed to get right at the source of the dust and chips. If I were an engineer, I could probably come up with something better.

Given the required investment of x2 <$20 armatures, a nylock nut, and some zip-ties, it's still represents a superior return on my investment. I've just not found any after-market setup that isn't insanely expensive or questionably effective.
 
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