wingless' Custom High-Volume High-Pressure Oasis Compressor System

wingless

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The air horns and whistle on my boat need a compressed air system.

This system was designed by me to satisfy those requirements and to also be available for 100% duty cycle for air tools.

Here is my 2000 380 Searay Sundancer.

StrataglassWindowsOutside2_zps4402afac-1.jpg


The first step was selection of a compressor. I chose a Oasis XD3000-12 compressor. This has been customized to add features like forced air cylinder / head cooling, like is present on the XD4000-12 compressor, only mine has much more airflow and mine has ductwork to suck in fresh, exterior air.
Oasis XD3000 Compressor: http://aircompressors.oasismfg.com/...d3000-extended-duty-air-compressors/item-1050
Oasis XD4000 Compressor: http://aircompressors.oasismfg.com/...000-continuous-duty-air-compressors/item-1052

The compressor is located in an inaccessible / unusable area of the hull, between the inner and outer hull. This volume is outside the ignition-protected environment, where it is prohibited / unwise to install anything that makes a spark, like this compressor, that could ignite gasoline vapors, even though those vapors should not exist. This is an ABYC (boat) requirement. When I inspect the compressor, like for checking the oil level, I need to unscrew and slide-out the ice maker. Then I have excellent access.

The compressor location has access to exterior air, but not enough to provide acceptable cooling. My system has one of these 4" 220CFM SHURflo yellowTAIL In-Line Blowers w/ ducting to the exterior, then to a custom shroud dumping onto the compressor cylinders / head.
4" 220CFM SHURflo yellowTAIL In-Line Blower: http://www.shurflo.com/marine-products/more-marine-products/blowers/129-yellowtail-4-blower

This location is very handy. It is directly above my battery bank. I am using one of these 200A Blue Seas Systems 187-Series Circuit Breakers to provide both the circuit protection and the power feed on / off function. The compressor is wired to power the fan whenever the compressor is running. I will monitor the head temperature to determine if it would be better to reconfigure the fan power to have the fan instead thermostatically controlled. I also have a dash-panel enable / disable switch for the compressor.
Blue Seas Systems 200A 187-Series Circuit Breaker: https://www.bluesea.com/products/7149/187-Series_Circuit_Breaker_-_Surface_Mount_200A

The compressor location has access to exterior air, but not enough to provide acceptable cooling. My system uses the SHURflo yellowTAIL In-Line Blower w/ ducting to the exterior, then to a custom shroud dumping onto the compressor cylinders / head.

Here is the design for the custom shroud and the location for the fresh air 4" duct input for the head / cylinder cooling for my Oasis XD3000 compressor.

My design permits me to relocate the on/off switch to the shroud. The low-voltage indicator lamp is relocated to my new dash rocker switch, having one indicator lamp for power, one for low voltage.


CAD Design
OasisShroud_zps4f8bf517.jpg



Welded Shroud and Inlet Locator
XD-3000AirDucts_zpscc0f15cb.jpg



Exterior Air Inlet
380DAExteriorAirOpening_zps951bfe92.jpg


This is the Nason CD-1B4-150J/WLVT187 100 to 250 p.s.i. adjustable pressure switch. According to the linked data sheet, this is a 100 - 400 p.s.i. adjustable switch w/ a ¼" NPT male connection, normally closed contacts, adjustable rising setpoint, 18" wire leads, Viton 514 AD diaphragm, w/ a slotted head, instead of Allen head, adjustment lock screw.
Nason Pressure Switch: http://nasonptc.com/pdfs/Switches_Catalog.pdf


NasonPressureSwitch_zps5cad3a8a.jpg


This is the check valve. It is a Control Devices CA-12 Load Genie Unloading Check Valve. It is a 3/8" NPT valve, rated for 3 to 12 CFM flow.
Check Valve: http://www.cdivalve.com/products/valves/air-compressor-valves/unloading-check-valves

The internal moving mechanism could be hurt by excessive torque. The instructions specify 10 ft-lbs of tightening torque, maximum.


PA-12LoadGenieControlDevicesInc_zpse09a6396.jpg


The installation uses a combination of flexible hoses and rigid pipe for the air distribution.

The compressor is connected to a 3/8" diameter by 2' long Viair Stainless Steel Braided Leader Hose. This will provide vibration isolation from the compressor.

The system uses rigid 1" diameter Type L copper tubing for the primary distribution. This is around the compressor and the engine room. My plan is to run the tank and plumbing at up to 200 p.s.i. to the high-CFM regulator that then feeds the horn and the whistle valves, also the air chuck.

My system is using this 15 gallon, 200 p.s.i. working pressure tank. I have mounted this upside down, bolted to the ceiling of the engine room.


ViairLeaderHose_zpsbed3e065.jpg



15Gallon200psiTank_zps13eeb3b3.jpg



The tank was sanded down for a fresh paint job.

The threads for the port openings were all chased w/ the appropriate-size pipe thread tap, to clean out any prior crud.

The nipples were all selected to be the extra-thick wall Schedule 160 seamless black steel parts, to tolerate the 200 p.s.i operating pressure.

The tank has one ¼" fitting, that was used for a drain, but I have mounted this upside down, so I have used the high-pressure forged black steel square head plug for this and for all other unused fittings.

There are three ½" NPT fittings across the top, now bottom, two are plugged, one is being used for a drain.

The side ports are 3/4" NPT. The air entry has a short nipple, then a 3/4" to 1" coupling, another short nipple, then a dissimilar metal union, so all the rest of the plumbing can be 1" Type L copper.

My plan was to have the air passages as large as possible throughout the system, all rated for 200 p.s.i. working pressure.

My preference is to use pipe dope, instead of tape. On this project, I assembled the fittings, cleaned off the dope, then painted.

3-4to1FittingandDissimilarMetalUnionwPipeDope.jpg


3-4to1FittingandDissimilarMetalUnionCleaned.jpg


TankPaintedRed1.jpg


TankPaintedRed2.jpg


TankPaintedRed3.jpg



This system has been mounted on a boat w/ gasoline engines. As such, the compressor and all other electrical components need to either be ignition-protected (won't make a spark) or must not be mounted in the engine room (which extends to a defined ignition-protected volume), both to be compliant w/ the ABYC standards and to follow common sense and not create the possibility to blow up.

On my boat there is a volume alongside and aft of the ice maker, on the port side of the boat that is outside the ignition-protected volume. The compressor is mounted in this volume. It has access to forced fresh air, via a duct and blower, dumping air onto the cylinder head and providing air to the compressor intake. Excess air exits through existing openings.

The initial testing shows GREAT results. There is a HUGE volume of air dumping across the head, using the blower and my custom shroud.
It is close to an ideal location. It is a short electrical run to the battery banks. (It will be wired through a 200A circuit breaker to three 125Ah AGM batteries and I can easily connect two more, if required.) It has plenty of fresh air. My preference is to bolt components in-place, but I cannot do that w/ the compressor, so I am using the 3/4" plywood that will be lag-screwed onto the deck. (One of the 140 gallon fuel tanks is below that deck, so I cannot access the other side to position a nut or bolt.) The oil level will be visible only after sliding-out the ice maker. This is a dry location, not exposed to any water.

The new plywood mounting plate is epoxy-coated, along w/ the rest of that volume, on top of existing resin and gel coat, for additional protection.

Part of the installation is to remote mount the on/off switch, on/off indicator and the low-battery indicator onto the dash, w/ all the other switches. I was able to locate a SPST switch w/ two indicators that matches the existing switches and will fit into an existing empty position.

This custom installation requires that I design and create a circuit to take the existing integrated LED indicator / circuit and make it instead drive the new incandescent indicator in my new dash switch. I designed, built and tested that new circuit. It works great. The second indicator comes on, as-expected, when the battery voltage drops low, when the compressor shuts-down due to low voltage.


New Switch On
CompressorSwitchOn.jpg


New Switch Low Battery
CompressorSwitchLowBattery.jpg


Compressor Mounting Location
CavityAftofIceMaker.jpg


Compressor Dry Fit
DryFitCustomXD3000inCavity.jpg



This 200 PSI 15 gallon Manchester Tank is mounted upside down in the engine room, bolted to the engine room ceiling / floor of the transom locker storage compartment.

A scissors jack was used to push the tank up against the ceiling to bolt it tightly in-place.

TankMounted1.jpg


TankMounted2.jpg



The system is plumbed w/ 1" pipe / tubing throughout. The 1" Type L copper is used from the tank through the regulator, to the air chuck and to the 1" ID 300 PSI Buna-N flexible hose, going through the arch to the horns and whistle.

As much MAP torch soldering as possible was done off the boat. The fiberglass and gasoline are WAAY to flammable.

This is the manifold leading from the tank to the regulator and the fill hose / check valve.

TanktoRegulatorPlumbing.jpg
 
This shows the manifold from the tank exiting the engine room above my six Group 31 125Ah Lifeline AGM batteries. My boat has three battery banks, the starboard bank w/ three batteries for the house, the port w/ two batteries for the helm electronics and the generator has one battery. I also have a rotary switch to short the port and starboard banks into one five battery bank.

This also shows the Blue Sea Systems ANL Fuse Block holding the 200A fuse leading to the Oasis compressor. The ABYC marine standards require this to be placed close to the battery.
Blue Sea Systems ANL Fuse Block: http://i101.photobucket.com/albums/...t/Air/OasisLowVoltageBoardComponentSide-1.jpg

This plumbing is visible when opening the engine room compartment.


AirPlumbingAboveBatteriesand200AANLFuse.jpg



This is the continuation of the manifold, outside the engine room. This plumbing is hidden by screwed-in-place storage compartment bins. This shows the check valve and hose from the compressor and the plumbing leading to the regulator and pressure switch.

ManifoldtoRegulatorSwitchCheckValveandFillHose.jpg



This is the manifold from the regulator to the pressure switch.

ManifoldtoRegulatorandPressureSwitch.jpg



Here is the regulator, pressure switch, Blue Sea Systems on/off 200A circuit breaker, air chuck and manifold leading to the horns and whistle.

This compartment is accessible when opening a door. This compartment is used to hold my fire extinguishers and safety flares.

RegulatorPressureSwitchCircuitBreakerandAirChuck.jpg



Here is the manifold leading from the regulator, to the air chuck and to the horns and whistle. This manifold is hidden in the volume behind my ice maker and is accessible by removing the screwed-in-place ice maker.

AirChuckManifold.jpg



The mounting for the custom Oasis XD300-12 Compressor was a challenge.

On the port side of my 2000 Searay 380 Sundancer there is a built-in ice maker, behind a door, under the counter. When that ice maker is removed it exposes an inaccessible, unused volume. That is the location for the compressor.

This volume does not have any airflow. It has only one hidden exterior air opening, permitting air ingress or air exhaust., but no natural cross flow.

The floor of this volume is directly above one of my 143 gallon gasoline tanks, so it is not possible to bolt the compressor to this surface. I designed and created a mounting plate for the compressor, that is secured to the floor using lag screws around the perimeter.

The mounting plate is made of 3/4" plywood, coated w/ epoxy for protection. I also added a 1" polyester webbing strap to retain the motor to the mounting plate.

The system must be very secure, especially when the seas get rough.


Volume Before Modifications
CavityAftofIceMaker.jpg


Initial Dry Fit
DryFitCustomXD3000inCavity.jpg


Mounting Plate
OasisCompressorMountingBoard.jpg


Motor 1" Polyester Webbing Strap
OasisCompressorMotorStrap.jpg


Motor Secured by Webbing
OasisCompressorMotorStrap2.jpg


Compressor Installed
CustomOasisCompressorMountedWiredVentedandPlumbed.jpg



Part of the compressor modification includes the addition of high-volume forced fresh air cooling onto a custom-designed / fabricated cylinder head plenum.

The sides of my boat has teardrop-shaped openings to permit engine combustion air ingress and also for blower exhaust. The tip of that opening was modified to add a custom-designed / fabricated 4" flexible vent hose support.

The partition wall separating the compressor volume from the volume above the engine compartment was modified to drill a 4" mounting hole to mount the Shurflow 4" 220 CFM Yellowtail Blower to that partition wall.

The blower is currently wired to run when the compressor runs. An in-line fuse is used to fuse the blower to the specified 7A[/URL], instead of the 200A feeding the compressor motor.

This forced air cooling works GREAT!

There is plenty of fresh exterior air flow dumping across the cylinder head. I can grab onto the head while the compressor is running and it is not hot.


Exterior Air Inlet
380DAExteriorAirOpening_zps951bfe92.jpg


Exterior Air Inlet w/ 4" Vent Cut Modification
CoolingVentShroud4InchCut.jpg


Exterior Air 4" Vent Support
CoolingVentSupport.jpg


4" Partition Hole
4InchCoolingAirHole.jpg


Suction-side Vent Hose
CoolingVentHose.jpg


Exterior Air Inlet
CoolingVentExteriorOpening.jpg


Pressure-side Vent Hose and Blower
CompressorCoolingAir1.jpg


Custom-designed Cylinder Head Shroud
OasisShroud_zps4f8bf517.jpg


Exterior Air Inlet and Cylinder Head Shroud
XD-3000AirDucts_zpscc0f15cb.jpg



This is the air valve manifold, buried in the arch below my open array radar pedestal. The manifold is secured in-place by four tapping screws into the radar arch reinforcement holding the valve brackets.

There is one 3/4" HornBlasters valve for the whistle and a ½" HornBlasters valve for the horns.
3/4" HornBlasters Whistle Valve: URL=https://www.hornblasters.com/products/details.php?i=hornblasters-3-4-in-brass-air-valve
½" HornBlasters Horn Valve: URL=https://www.hornblasters.com/products/details.php?i=hornblasters-diablo-1-2-in-brass-air-valve
 
I think soldered joints and compressed air is a very bad idea. How can you tell how good each joint is?? I can see the joints are smothered in solder but actually the bond is made in the joint not round the outside.

Long term those soldered joints will be subject to surges of pressure up to 200 psi and down to something less as the compresser fights to keep up the air supply. this cyclic duty will bear on all those joints.


These fittings are meant for lowish pressure water not high high pressure compressed air and if a joint should let go it could be a catestrophic ballistic failure.

Usually compressed air distribution is done through screwed pipe joints and steel pipe for a very good reason I suspect.
 
I has similar reservations about soldered copper. I'd have used plastic air hose. The flex in a fibreglass boat might also be a contributor to failure.
 
I think soldered joints and compressed air is a very bad idea. How can you tell how good each joint is?? I can see the joints are smothered in solder but actually the bond is made in the joint not round the outside.

Long term those soldered joints will be subject to surges of pressure up to 200 psi and down to something less as the compresser fights to keep up the air supply. this cyclic duty will bear on all those joints.


These fittings are meant for lowish pressure water not high high pressure compressed air and if a joint should let go it could be a catestrophic ballistic failure.

Usually compressed air distribution is done through screwed pipe joints and steel pipe for a very good reason I suspect.
The system was designed w/ appropriate safety margin for the components and application.

This link shows the pressure ratings.

http://www.alascop.com/pdf/cu/water_tubing_1.pdf

The process of soldering is to use solder flux, heat and capillary action to draw the solder into the joint, so that the bond exists on the entirety of the mating surfaces. FWIW, an examination of a de-soldered joint shows complete interior colder coverage, not just the exposed fillet.

It is very common for soldered copper to be used for air distribution.


I has similar reservations about soldered copper. I'd have used plastic air hose. The flex in a fibreglass boat might also be a contributor to failure.
The distribution uses both copper and flexible tubing.

The copper is isolation mounted onto a contiguous hull structure, using rubber-cushioned stainless Adel clamps.

Yes, if the hull splits in-half, the air distribution will leak.


When he blows his horns, his boat goes dead in the water...
Huh?
 
You have just shown a table for the tubing, I dare say the tubing is strong enough to take the pressure, my comments were about the fittings and joints. The only way you can know that proper bonding has taken place is by destroying each and every joint to examine it. Bearing in mind that you have set out this thread like an instructional one, I don't recommend that anybody follow your lead - it does not represent best practice. not fit for purpose.

lead or lead substitute soldered joints are not the way to go for compressed air, silver soldered joints would have been stronger and less likely to come apart.
 
You have just shown a table for the tubing, I dare say the tubing is strong enough to take the pressure, my comments were about the fittings and joints. The only way you can know that proper bonding has taken place is by destroying each and every joint to examine it.
Sorry, but I have been soldering copper pipe for decades and decades, both w/ 50/50 tin/lead and w/ 95/5 lead-free.

All of my homes have been plumbed w/ copper for the water supply. All my work buildings have been plumbed w/ copper for the air supply. I remain comfortable and confident that my solder joints will satisfy the requirements for the life of the boat w/o requiring X-Ray analysis to verify a good joint.


Bearing in mind that you have set out this thread like an instructional one, I don't recommend that anybody follow your lead - it does not represent best practice. not fit for purpose.
That is an assumption. There is nothing instructional about this topic. The steps shown here are not a recommendation.

This topic shows what I did on my boat, after researching the specifications and analyzing my requirements.

Follow this information or deviate from my implementation, depending upon your requirements, preferences and conclusions.


One requirement that is not obvious is supplying my Kahlenberg 117 whistle w/ ample airflow. That is why I selected a 1" ID air distribution system. My air distribution system is perfect for the whistle.

Yes it is POSSIBLE to build the system w/ threaded steel pipe instead of soldered copper fittings, but the wall thickness mandates a MUCH larger pipe size to maintain the same ID. It is possible to use flexible tubing in-place of soldered pipe, but there are many tee and ell fittings that are required for my system. IMO, the soldered copper manifolds are the MOST appropriate implementation for the the valve manifold, the regulator / check valve / high pressure shutoff switch manifold and for the air chuck manifold.

The Goodyear Ultra Grip non-conductive hose I used for the distribution, after the regulator, has very good characteristics and is very good for the application. I used split loom to provide abrasion protection for the hose.
http://www.aaahose.com/products/air_and_multipurpose/goodyear/ultra-grip


IMO, this implementation is entirely fit and appropriate for my purposes.
 
An unusual and interesting project. It must have taken some time to put the post together so thanks for sharing :)
 
An unusual and interesting project. It must have taken some time to put the post together so thanks for sharing :)

I agree, I wasn't sure which took longer, the project or posting the thread. Major effort, thanks. :cool:
I found it interesting from start to finish and also some of the replies. I would like to ask a couple of questions tho...

1. What is the max. air pressure at top limiter cuts in?
2. Why do you need air tools on a boat? My air horns run from a tiny compressor on plastic tubing. (Khalenberg single)
3. What gave you the idea?
4. As mentioned above - Why is Copyright important to you as this a completely personal project with no commercial application?

Thanks again, and welcome to the forum.

RR
 
Wingless


Welcome

Just do bear in mind that this forum has members with simply astonishing knowledge across a huge range of topics. I am not one of them regarding air horns BTW. Experts range from engines to more than you could ever guess or think of asking about a "simple" lead acid battery and how you connect it.

Very few people on here knock anything for the sake of it (that is what the lounge is for apparently!).

Don't be too defensive!


Jeremy

Sorry, but I have been soldering copper pipe for decades and decades, both w/ 50/50 tin/lead and w/ 95/5 lead-free.

All of my homes have been plumbed w/ copper for the water supply. All my work buildings have been plumbed w/ copper for the air supply. I remain comfortable and confident that my solder joints will satisfy the requirements for the life of the boat w/o requiring X-Ray analysis to verify a good joint.


That is an assumption. There is nothing instructional about this topic. The steps shown here are not a recommendation.

This topic shows what I did on my boat, after researching the specifications and analyzing my requirements.

Follow this information or deviate from my implementation, depending upon your requirements, preferences and conclusions.


One requirement that is not obvious is supplying my Kahlenberg 117 whistle w/ ample airflow. That is why I selected a 1" ID air distribution system. My air distribution system is perfect for the whistle.

Yes it is POSSIBLE to build the system w/ threaded steel pipe instead of soldered copper fittings, but the wall thickness mandates a MUCH larger pipe size to maintain the same ID. It is possible to use flexible tubing in-place of soldered pipe, but there are many tee and ell fittings that are required for my system. IMO, the soldered copper manifolds are the MOST appropriate implementation for the the valve manifold, the regulator / check valve / high pressure shutoff switch manifold and for the air chuck manifold.

The Goodyear Ultra Grip non-conductive hose I used for the distribution, after the regulator, has very good characteristics and is very good for the application. I used split loom to provide abrasion protection for the hose.
http://www.aaahose.com/products/air_and_multipurpose/goodyear/ultra-grip


IMO, this implementation is entirely fit and appropriate for my purposes.
 
I agree, I wasn't sure which took longer, the project or posting the thread. Major effort, thanks.
You are welcome.

1. What is the max. air pressure at top limiter cuts in?
There is not a top pressure limiter electrical switch. The Nason CD-1B4-150J/WLVT187 100 to 250 p.s.i. adjustable pressure switch is used to control the pressure setpoint. Lately, I've been running at around 160 PSI and that has been working fine for all my air uses.

The maximum specified operating pressure for many components is 200 PSI, so I selected a high-volume pressure relief valve to provide protection while permitting operation at that setpoint.

2. Why do you need air tools on a boat? My air horns run from a tiny compressor on plastic tubing. (Khalenberg single)
My boat is next to my home. I do not expect to ever have a compressor at home again. When working in the driveway I just stretch a couple of long hoses and I am all set.

My Kahlenberg D-1 Chimetone air horns are happy w/ any compressed air source. They sound fine using a ¼" air hose and a blow gun.

My Kahlenberg 117 whistle is another story. That wants / needs volume. It does not sound using that same blow gun. On the other hand, that large whistle WILL sound using lungs and lips, albeit quietly. The whistle was the reason I selected a 1" distribution system, to provide a 20' reserve column of unrestricted high-volume air, before even starting to draw from the tank.

3. What gave you the idea?
Deep thought. I do a big boat project each year.

4. As mentioned above - Why is Copyright important to you as this a completely personal project with no commercial application?
These are my images, that I created, composed, edited and posted to provide information, so I watermark them to show the origin.

Thanks again, and welcome to the forum.
Thank you.
 
When he blows his horns, his boat goes dead in the water...


From the recoil

The original Star Trek Enterprise had Kahlenberg Chimetone horns instead of shields to repel alien bad stuff, until the Technical Support Guru informed the producers: "in space no one can hear you scream".

Fortunately my boat operates in Earth's atmosphere, so the sound wave is fully effective, while people are screaming.
 
You are welcome.

My Kahlenberg D-1 Chimetone air horns and My Kahlenberg 117 whistle

What a system! So the D-1 signals that your Searay is between 20 and 75m in length (!) and the whistle is just for fun?

When I visited Kahlenberg in Wisconsin I was shown the largest Mississippi ferry whistle horn they'd ever made. Three enormous pipes, between 4' and 6' tall and 8" to 10" wide mounted parallel on an equally sized manifold. The whistle stood on its own in a large concrete block room, fed with air from a colossal storage tank in the crypt. Outside the room and with the door firmly closed, I pulled the lever to release the air. A noisy whoosh of air rushed towards the whistle to wake it up, followed by the most gorgeous harmonised sound! It was so, so loud, I ducked and involuntarily burst out laughing. But I had to release lever after four seconds since in that short period of time, it drained the air supply. Memories of the old black and white mystery movies....

Sadly, it gone. It was sold.
 
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What a system! So the D-1 signals that your Searay is between 20 and 75m in length (!) and the whistle is just for fun?
Thank you!

These Kahlenberg D-1 Chimetone horns were originally on a mega yacht near my home. They decided they needed an even more mega horn, so these were pulled to a marine salvage yard.

The next owner worked in that yard and he put them in his pickup truck!

These became available probably because the little compressor he was using stopped working and the check valve was leaking badly.

The Kahlenberg 117 whistle has a terrific sound. Here is a clip.
http://vid101.photobucket.com/albums/m52/wingless-pics/Boat/Air/Kahlenberg 117 A-V.mp4

These are all for fun. These are also used per USCG regulations regarding fireworks displays, where they require all boats in-attendance to sound their horns after the finale. I let everyone else go first, then sound the D-1 horns. There is nothing else to say after that...

When I visited Kahlenberg in Wisconsin I was shown the largest Mississippi ferry whistle horn they'd ever made. Three enormous pipes, between 4' and 6' tall and 8" to 10" wide mounted parallel on an equally sized manifold. The whistle stood on its own in a large concrete block room, fed with air from a colossal storage tank in the crypt. Outside the room and with the door firmly closed, I pulled the lever to release the air. A noisy whoosh of air rushed towards the whistle to wake it up, followed by the most gorgeous harmonised sound! It was so, so loud, I ducked and involuntarily burst out laughing. But I had to release lever after four seconds since in that short period of time, it drained the air supply. Memories of the old black and white mystery movies....

Sadly, it gone. It was sold.
Wow!

As you know, the load presented by the whistle to the air supply is virtually identical to an open pipe.
 
When I visited Kahlenberg in Wisconsin I was shown the largest Mississippi ferry whistle horn they'd ever made. Three enormous pipes, between 4' and 6' tall and 8" to 10" wide mounted parallel on an equally sized manifold. The whistle stood on its own in a large concrete block room, fed with air from a colossal storage tank in the crypt. Outside the room and with the door firmly closed, I pulled the lever to release the air. A noisy whoosh of air rushed towards the whistle to wake it up, followed by the most gorgeous harmonised sound! It was so, so loud, I ducked and involuntarily burst out laughing. But I had to release lever after four seconds since in that short period of time, it drained the air supply. Memories of the old black and white mystery movies....

Sadly, it gone. It was sold.
Is this the whistle at time 3:05? It is very impressive!

https://www.youtube.com/watch?v=1cswiutb074
 
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