Using electric duct dampers as blast gate substitutes

[Daniel Dadourian]

Anybody have any experience using electric duct dampers as remote controlled blast gates. Rockler is now selling these in home automation, more for HVAC. I wonder if these can be used for blast gates in tough to reach locations in a central dust collection setting. Others have posted that having the damper in the stream (as long as it opens completely) has not been a problem.

I would envision using these with a single 24 Volt transformer and a toggle switch at each machine that can be turned on when the specific machine is in use. I could use a separate commercially available wireless remote to power-on the DC.

Here is a link to the product, made by Suncourt: http://www.bestqualitysupplies.com/S...zonemaster.htm

Thanks.

[Jamie Buxton]

I use duct dampers (they're cheap) instead of blast gates to control my dust collection ducts. They work, but the one that controls a leg which includes a floor sweep occasionally gets hand-plane shavings wrapped around it. With too many shavings, it doesn't move easily. In my set-up it is easy to take the duct apart to remove the shavings.

[Lee Schierer]

The duct dampers I've seen don't close very tightly (they seem to have a 1/8-/14" gap aroung the damper), so on a system with several of these, I would think you would have a lot of suction loss to the unused tools.

I have one damper style blast gate in my system. It is the only one that has ever clogged. It connects my TS to the DC system.

[Tom Veatch]

Anybody have any experience using electric duct dampers as remote controlled blast gates. ...

I use remote activated internal dampers for all my blast gates. They are shop built rather than commercially available devices like that shown in the link, but the functional design is identical. They are based on plans published in Woodwork Magazine. So far there have been no problems with clogs, even on the jointer or planer which is where I'd expect problems if there were going to be any.

I did experience a bad clog at the tablesaw during some extensive cutting of wet PT material, but that was a mechanical failure of the damper, not a failure of the design. The damper connection to the actuator loosened and the damper failed to open fully.

[Leigh Betsch]

Tom, are there any on-line plans for these shop built dampers?
Any one else have plan for shop built blast gates, automated or namual?

[Sonny Edmonds]

Since what you want is to remotely operate your gates, why not just use choke cables and multipliers with a linkage to the gate?
I have three gates I operate remotely. One at the front of my TS for a gate behind it. One for my router stations, also behind and controlled from the front. And one for one of my lathes that is up high on the overhead, but has the knob down low under the bench the lathe lives on.



There is more about it over here.
Incidentally, I just use cheap 4"plastic gates. I have had to repair two of them in the past 15 years, but otherwise they work great for me.

[Tom Veatch]

Leigh, I don't know of any on-line plans other than through back issues of the magazine. There's a little more information in this post:
http://www.sawmillcreek.org/showpost...3&postcount=28

[Chip Lindley]

WTG Sonny! But, not nearly *high-tech* enough for some here!

IMO, the downside with electric *dampers* is that they do not create a seal, as a blast gate does, sliding in its mating groove. If several of these are used, significant efficiency will be lost in the DC system due to leakage around the *dampers* which do not plug the hole tightly. Even when *open* these dampers will add a small constriction to the duct system because of their physical presence.

[Daniel Dadourian]

Thanks for all the input. Sonny's
solution looks great! ... simple, inexpensive and will work with my old blast gates.