So, I have this massive Gast pump that I could no longer use for overnight lams due to noise.
A
lam shop looking to incorporate bagging for their EPS/Epoxy boards is
interested in the pump but are also pretty new to the whole bagging
thing.
We started talking about what the schematic for a multibag setup would look like.
This is a little overblown, but this is what I was sort of envisioning:
All white sections are assumed to be brass/galvanized tubing.
Starting
at the pump, there is a filter that sits just before the pump to make
sure debris doesn’t make it in to the system, this then branches out in
a tree like fashion to N end points.
At each endpoint, we first have a valve that allows us to open/close that particular stem.
A
bleeder valve allows me to tune the vacuum level at that specific node
with a vacuum gauge behind it to display the local vacuum level.
From
there it goes to a simple barb connector…to hose…to bag connector
attached to a 36" nylon bagging tube sealed with bag clamps.
I
believe that some folks here have had production experience with multi
bag setups…I’m just wondering if I’m warm or if I’m overdoing
it…what am I missing. I realize that some of this may border on
proprietary information but any insight that you’re willing to share
would be greatly appreciated.
I got logged out when attempting to post…I even checked the forum before I attempted to repost to make sure I didn’t create a dupe but I still managed…
Please respond to this thread…let the other one die.
Administrators please feel free to dump the other one.
Looks good. If it is anything like an air pump manifold system, it might take some tuning at one end to get the perfect pressure at the other end but that looks like the ticket.
You might try PMing Bert Burger. I know he has direct experience with multiple vacuum outlets off one pump.
So on the pump side of the manifold you’d have a reservoir and a vacuum switch set to near the total amount of vacuum the pump can obtain.
On the bag side of the manifold youd replace what you call a vacuum valve (really just a ball valve) with an electric / solenoid valve. Ditch the bleeder and put a vacuum switch there hooked to the electric valve for that station.
Good vacuum switches can be set pretty quickly and accurately to the vacuum level you want. Keep the gauge at each station.
To maximize reservoir run 3" pvc schedule 40 pipe. You could use a lesser quality pipe in areas where you did not want to pull near 29"Hg. But probably from your pump to the manifold. And then the areas where you want your stations.
would it be possible to skip all the bits and stuff, just have one manifold switch and guage and t section off after the manifold straight to the bags no conectors just masitc
yeah i reckon the go would be to have one manifold with a bleed valve the right size to give you full control, but you would have to put everything on at once and then set your vacuum.The idea would be to have a closed loop control system, an electronic vacuum gauge, PID controller and and electric or pnuematic bleed valve all using 4-20mA loop signals.That way as you were putting boards on the system and/or removing them throughout the working day the vacuum would be automatically controlled to a vacuum set point.
Silly, I see where you’re going, but I’m thinking that I need bag connectors since ultimately…all of this is sitting in an post cure box and will require minimal time to get a board in, hook it up and pull.
Mastic seems like it could add some time and after a while, the connectors probably wind up saving you a little dough.
In terms of having independent bag nodes all individually controlled and gauged…I just worry that if one bag is “tighter” than another that it could lead to differences in vacuum levels between bags with no real way to monitor or adjust.
If you put a system together like I mention above, you could use a vacuum switch with an adjustable deadband on the pump side of the manifold to set your pump up to run even less, dependent on the amount of reserve reservoir you build into it. So you could set it to pump up to near max but only turn on again if it falls below a certain level. Use water filters for line filters, one for each station and one just before the pump.
The problem I’ve had with a switched system is that the pump pulls 60amps at startup.
It blew out the Joe Woodworker switch and no one else could recommend an affordable solution to dampen the amperage to the switch or to get a switch that could handle the load.
The pump is rated to run continuously…it’s a beast.
I would not suggest the JW (Air Logic) switch in a commercial production setup. That thing is basically a toy compared to commercial switches.
Did you follow the instructions on the JW site for larger, higher amperage, pumps? Did you install a mac valve and a relay switch to reservoir/sub-reservoir system with that Air Logic switch you blew out?
I think you’re on the right track man with the setup in the first post. Even if you don’t use any switches, I think a reserve tank would be a good idea to keep suction even. On the subject of switches, what about using a relay that’s rated for the kind of start-up amperage your pump takes? The vac switch could just flip the relay, then the relay could handle the actual electrical load. Just an idea. You’d have to use a pretty big reserve tank to minimze the switching, but in a real production setup it might help extend the life of your pump.
I didn’t get relays until someone explained them to me. I’m totally non-electrical too.
They’re actually pretty simple, and neat. A relay is a switch.
“Relays are widely used
in electrical applications where one circuit is to be energized or turned
“on” by the presence of a voltage, provided by another circuit.”
Your pump requires a large current. Your vacuum switch can only handle a smaller current. The current for the pump can pass through a relay switch which can handle it. That relay can be activated by the smaller current that your vacuum switch can handle. The current that goes through your vacuum switch is the “finger” which flips the switch in the relay.
Google relays. They’re simpler to use than you imagine, and could definitely solve this problem.
They can be had for a bit less than what JW sells them for.
The sub reservoir with the mac valve is a great idea so that the pump draws less amperage at startup (any pump). Or at least if on the pump side of the manifold you have near full vacuum.
Are you actually going to setup a professional production shop?
Im with schwuz on the relay… thats what i did with my setup when
my switch couldnt handle the amperage of the pump.
The only problem with the relay is that it has to be powered by a separate voltage source. I dont think you can use standard 120VAC that comes out of your wall… most run off 10V DC I think, but I may be wrong. (A 12V battery might work but dont know how long that would last)
You will put a relay where your vacuum switch is in the pump circuit. Then you will make a separate circuit with the vacuum switch and your power supply connected in series to the “control” terminals on the relay. Then when the vac switch senses lack of pressure it will trip the relay that will turn on your pump, and vice versa.
A place like this http://www.marvac.com/default.aspx would be able to get you exactly what you need, there is one near me and the employees are generally pretty knowledgable. The closest to you seems to be costa mesa though. You should be able to get a relay rated for that amperage no problem, and they can better explain to you how to implement it. Or you could contract me out and i’ll buy the parts here and make a weekend trip out of it… haha
I envision the setup you have above, but just have manual open or close valves at each “node” (vise clamps on the hoses?) and one giant resevior and one vacuum control circuit. If only one bag is in operation the pump will hardly be working with the rest of the valves closed, otherwise, with a big enough resevoir and good seals on the bag it should work fine while running several at a time.
I appreciate your insight and input…Tyco is the place that Joe pointed me to when we troubleshot the problem, but I must have incorrectly explained my requirements because they quoted some shniz that was over $100…
