self cleaning blast gate questions

[Trey Isbell]

For some reason it just struck me today that if you have a self cleaning blast gate you have suction loss because when the gate is open the bottom of the gate has a open slot in it. I don't have any blast gates like this but just wanted to know what creekers think about theres. I know sawdust will pack down in the bottom of one that is not open but it seems like you could just clean them every once and a while.:)

[nic obie]

Hey Trey,

I don't have them but I wish that I did.

I have the other kind.

I have had to grind out the back of the blast gate in order to be able to shut the thing down all the way.

I don't think that the leakage will amount to much.

[Doug Shepard]

I've actually been contemplating making my own so I'm glad you asked this. I've never looked at any close up but wouldn't the loss of suction issue (however small) be there regardless of whether it was open or closed?

[Noah Katz]

The suction should pull the gate closed and allow minimal leakage.

[Trey Isbell]

The suction should pull the gate closed and allow minimal leakage.

I am talking about when the gate is open I know that you will have minimal leakage when it is closed because of the suction.

["Gary Brewer"]

Trey: What blast gates have you looked at so far and and ones you really like?
Gary

[Trey Isbell]

I have looked at the article at bill pentz site on building your own. The only other ones that I have heard good reviews on are the lee valley self cleaning aluminum gates but then you run into problems using 6" s&d pvc pipe.

[Rod Sheridan]

I use the self cleaning blast gates, and yes there is some leakage, however to put it in perspective, on a 5" gate, the leakage through the open slot is aproximately 0.9% of the air flowing through the gate.

Note that this leakage is only present when the gate is open.

I guarantee that I was losing far more than that with conventional gates that wouldn't close, resulting in a constant loss at all the closed gates in my system.

Regards, Rod.

[Nate Folco]

Your gates don't have to have an open slot...
Not mine but I like the idea:
http://home.comcast.net/%7Es.muth/wsb/media/261991/site1031.jpg


http://home.comcast.net/%7Es.muth/wsb/media/261991/site1032.jpg