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bhays
05-23-2010, 09:33 PM
I am building some custom lab equipment for our new Frankenstein scene this year. One of the machines I am planning would have three clear cylinders on top, two smaller ones on each side and a large in the middle. I would like to have the fluid level in the two outer cylinders drop (drain out) as the large cylinder in the middle bubbles more and lighting changes, etc.

Does anyone have any ideas on how to handle the fluid transfer? I was wondering about skipping the pump idea and having a reservoir below the smaller cylinders with a piston type arrangement on a cylinder... as the cylinder retracted it would make room in the reservoir to allow the fluid to drain out of the cylinder above and when it extended, it would push the fluid back up into the cylinder... but how would I seal something like that to avoid leaks? Anyone have ideas?

Jim Warfield
05-23-2010, 10:23 PM
One valve opens as the other closes sending air into the cylinder forcing liquid to where you want to have it?
A relay with normally open and normally closed terminals like a air conditioning relay used to bring on the furnace blower when the Ac is on.
Of course using gravity is also pretty dependable .
I once made a hook up for my kitchen sink so when a button was pushed the normal water supply was substitued with a holding tank with water that had red food coloring in it so the faucet ran "Blood". The blood tank was pressurized via the city water supply so it ran from the faucet just like the water normally did.
I used to buy brand new washing machine valves for $3 or $4 from a local electerician , of course they need 120 volts, which could become tricky with water.

RJ Productions
05-23-2010, 10:30 PM
Since it's summer you could get a couple of those power soakers. You get the ones that are basically just a long cylinder. You stick the end in water, draw the handle back sucking water into the tube. Push it back and it squirts the water out.

Take two of them, thread a fitting into the ends and connect hose from the soakers to each of the cylinders you want to fill. Mount the two soakers together so that both handles are attached to an air cylinder. You activate the air cylinder and it pushes then pulls the handles on the soakers. Obviously you need to regulate the air cylinder so it is a slow movement.

Adjust the amount of liquid in the side cylinders connected to the soakers to get the desired effect. You could also vent the exhausts through a check valve and into the center tank to get the bubble effect.

Any other ideas??

Dreamreaper
05-24-2010, 08:17 AM
One valve opens as the other closes sending air into the cylinder forcing liquid to where you want to have it?
A relay with normally open and normally closed terminals like a air conditioning relay used to bring on the furnace blower when the Ac is on.
Of course using gravity is also pretty dependable .
I once made a hook up for my kitchen sink so when a button was pushed the normal water supply was substitued with a holding tank with water that had red food coloring in it so the faucet ran "Blood". The blood tank was pressurized via the city water supply so it ran from the faucet just like the water normally did.
I used to buy brand new washing machine valves for $3 or $4 from a local electerician , of course they need 120 volts, which could become tricky with water.

I picked up some valves last year on e-bay that are low voltage that I use with water and air on one of my props.

bhays
05-24-2010, 09:06 AM
Since it's summer you could get a couple of those power soakers. You get the ones that are basically just a long cylinder. You stick the end in water, draw the handle back sucking water into the tube. Push it back and it squirts the water out.

Take two of them, thread a fitting into the ends and connect hose from the soakers to each of the cylinders you want to fill. Mount the two soakers together so that both handles are attached to an air cylinder. You activate the air cylinder and it pushes then pulls the handles on the soakers. Obviously you need to regulate the air cylinder so it is a slow movement.

Adjust the amount of liquid in the side cylinders connected to the soakers to get the desired effect. You could also vent the exhausts through a check valve and into the center tank to get the bubble effect.

Any other ideas??

I think this is a good concept. I question the durability of those super soaker things, though. I am wondering if I can do something similar with pvc, make the bottom reservoir twice the diameter of the tube at the top so it doesn't have to be so long, then use some sort of diaphram to seal inside the pvc.. seems like I have seen a spud gun idea somewhere along the line that incorporated something like this..

as far as venting the exhausts through a check valve into the center tank... awesome idea there.. guess I will just have to go to the hardware store and poke around for parts...

bhays
05-24-2010, 10:34 AM
Found a site focused on building homemade super soakers from pvc.. looks interesting.

http://www.waterzooka.com/build.htm

Allen H
05-25-2010, 12:49 AM
Brett,
I really think you are on the right track with the water cannon plans. Here is a company in Indiana that has clear acrylic/polycarbonate tubing.
If you search for water mortar or water cannon you will get similar results, here is another good one.
http://www.instructables.com/id/Build-a-water-mortar-II--design-alternatives/

Phil Miller
05-25-2010, 07:47 PM
those super soaker pistons may wear out over time, how about using two SS or aluminum air cylinders? not sure how many ounces your trying to move? say you use two 2" bore with 18" stroke, nose mount. bolt both together with a flat bar by the nose mount, siide by side, then pin both clevis together with a bolt. the one air cylinder would be controlled by electric valve and Boo box, the other cylinder would have a hose to one end fill/ drain the two small clear cylinders and the other port of the cylinder would fill/drain the one large clear cylinder.

bhays
05-25-2010, 08:28 PM
those super soaker pistons may wear out over time, how about using two SS or aluminum air cylinders? not sure how many ounces your trying to move? say you use two 2" bore with 18" stroke, nose mount. bolt both together with a flat bar by the nose mount, siide by side, then pin both clevis together with a bolt. the one air cylinder would be controlled by electric valve and Boo box, the other cylinder would have a hose to one end fill/ drain the two small clear cylinders and the other port of the cylinder would fill/drain the one large clear cylinder.

That probably is a more durable solution. I am going to have to find the formula to determine volume of a cylinder. The two small cylinders will be about 1.5" and I would like to have about 18" of fluid in them when full, the center cylinder is about 5" (but it doesn't need to completely fill or empty.. so not worried about that side of things.

Does that mean I would need a 3" bore 18" stroke cylinder?

Allen H
05-25-2010, 08:45 PM
http://wiki.answers.com/Q/What_is_the_formula_for_finding_the_volume_of_a_cy linder&alreadyAsked=1&rtitle=What_formula_can_you_use_to_find_the_volume _of_a_cylinder
Math Bad!

bhays
05-25-2010, 08:57 PM
Seems to me that just basically pumping the water in and out of the slave cylinder with no other load would be pretty easy...

Do you think I could get away with three cylinders side by side with the center cylinder driving the two outside cylinders? That way I could use much smaller, less expensive cylinders..

The only concern would be whether the ports on the cylinders could flow the fluid quickly enough to get the effect I am wanting... I was thinking the entire cycle would be only 5-8 seconds in duration.. on the pvc super soaker I was going to be using a 2" bore with probably at least a 1" port..

Allen H
05-25-2010, 09:42 PM
The more I think about this, the more I think it would be easier to use small pumps that pump water into the cylinder, then another pump that pumps it out, then a Pic a boo controller could run it and it would be pretty easy, the size pump would be determined by the size of the cylinder, look at the GPH of the pump and you should be fine. Seal the acrylic tube with silicone caulk, each tube would have two hoses coming into the bottom, one in and one out. You could pump one right into the other or pump them both into the center cylinder. That would be alot cheaper to set up also I think.
www.sciplus.com has some great little pumps that are not to expensive.
Allen H

gadget-evilusions
05-25-2010, 10:54 PM
Brett,

I agree with the idea of using pumps vs. cylinders. I believe the cylinder idea would work, but I think it would be more work than needed.

I downloaded the waterzooka plans. Those are pretty cool, I will have to make a few to torture my nieces and nephews this summer.

bhays
05-25-2010, 11:02 PM
The more I think about this, the more I think it would be easier to use small pumps that pump water into the cylinder, then another pump that pumps it out
Allen H

I started out thinking pumps, but I am concerned about a couple of things. The effect I am looking for is that the fluid is draining out of the bottom of the two cylinders...

We've all seen this in a movie, where the two cylinders drain and the center one with the brain in it, etc. bubbles and goes crazy..

A pump with a high enough gph rating to move the fluid in a few seconds would spray a jet that would shoot six feet in the air... that's why I liked the super soaker kind of idea where I has basically moving the fluid from the upper cylinder to an equal size cylinder below with a port to pass through at least half the size of the total cylinder...

I suppose I could pump the fluid in and out of a reservoir below the cylinders with hole between the cylinder above and the reservoir big enough to get that action...

but would the pumps lose their prime... be sort of hard to time it so that you never ran the pump dry.

Allen H
05-26-2010, 12:35 AM
when you program a pic a boo you can watch the fluid levels while you do it, so it wont run dry. A baffle would stop the water from shooting up in the air, an air pump and airstone could add the bubbles in the center cylinder.
Just my thoughts, it helps me to keep things as simple as possible.

newhorror2010
05-26-2010, 06:50 AM
that either Liquid Nails or Red Gasket Maker (comes in a tube) would do the trick to seal your project. However, I see others have given you much more detailed info of what you could possibly do. There's my 2 cents.

John Elks

OblivionHauntedHouse
05-26-2010, 09:52 AM
Dave Oshefski from Shawano Manor in wisconsin has previously build a pretty sweet frank fluid machine for his blacklight 3d haunt. I am not sure how he exactly did it, but you could try contacting him. PM me for his contact info if you are interested.