Use of Dry Ice

The ongoing thread about the stuck chuck plate on Chippinchunk's LeBlond 13" lathe raised the idea of using dry ice to shrink the spindle and help break the bind.

Dry Ice is commonly used for chilling parts for shrink fits, as well as in certain situations, to break bound fits loose. My local welding supply sells dry ice in the form of chips, which is a handy form for use in shrink fitting of parts. Years ago, on a powerplant turbine erecting job, some body-bound dowels needed to be shrunk before being set in reamed/honed holes. The turbine erecting super was an old millwright with plenty of tricks and he was quite happy to teach people like myself- a green young engineer- what he could. He got a quantity of denatured alcohol (shellac thinner is a common version of this), and some steel pails. In those days, the dry ice came in the form of cakes rather than chips. He put the dowels, which were fairly hefty pieces of steel in their own right, and poured in the alcohol. The dry ice was broken into smaller chunks and dropped into the alcohol. As it was explained to me, the alcohol served as an excellent medium for heat transfer (or removal as the case was). Had the dowels simply been put into a box with the dry ice, it would have been a longer time to get them chilled down, and frost would have formed on the steel pins. The alcohol had a low enough freezing point that it remained liquid. The result was a fairly rapid chilling of the dowels.

At the powerplant, we had some large wicket gate bushings to be chilled for shrink fits. The method used was to build an insulated box out of rigid foam insulating board, along with plywood and framing lumber. The wicket gate bushings (made of a self-lubricating bronze called "Lubron") were placed in the insulated box along with cakes of dry ice. It took a good while to get the bushings chilled down since air was the heat transfer medium rather than a liquid.

A few years back, we needed to shrink some large cast iron valve guides to install in an Alco 539 diesel engine's cylinder head. These guides are many time larger than what would be found in an automobile engine. We were rebuilding the Alco cylinder heads in my buddy's shop, which is a good 25 miles from the welding supply. We agreed that since I had an account at the welding supply, I would swing by and get 25 lbs of dry ice chips. I brought a cooler and got the dry ice chips. My buddy had his own method for chilling the valve guides. Neither of us, or the railroad, was going to shell out the bucks for denatured alcohol. My buddy said an oldtimer had told him about using kerosene as the heat transfer fluid. He had plenty of that in his parts washing tank. We got a pail of kerosene and plunked in the valve guides and the dry ice. The effect was surreal. The kerosene bubbled and CO2 came off it, and we heated the cylinder head with a rosebud to help increase the temperature differential.

After maybe 20 minutes time, we pulled the first valve guide. The added benefit was the low temperature of the dry ice had thickened the kerosene so it clung to the valve guide. No frost issues, and a nice lubricant for the fit. By the time we got to the last of the valve guides, the dry ice had turned the kerosene into a grease, which was bubbling like a pot of stew from the dry ice.

About the time we got done with the cylinder head valve guide installations, I was wiping my hands and picking up my tools when there was a hell of a bang about like a 10 gauge shotgun going off. I jumped and started looking around, wondering if we'd overdid things with the shrink fit, maybe had a head crack. My buddy- a notorious practical joker- was standing behind me when I jumped and he burst out laughing as he saw me checking the cylinder heads for cracks. He stopped laughing and said that while I was finishing up, he'd taken some of the left over dry ice pellets and put them in a 2 liter plastic bottle with a little water, capped it up and left it under the shop window where I was working. He then had time to sneak back in and watch the results. I admitted he'd gotten the better of me, and he suggested, since it was my cooler with the dry ice pellets, that I take the rest home and "have a little fun" with my wife.

I arrived home and found my wife and daughter watching some mindless program or other on television. Wife asked how the job had gone, was happy to hear it went well, and I told her about the prank my buddy had pulled. Wife said she wanted to hear the "bang" for herself. I got a 2 liter plastic bottle out of the recycling bin, put in some dry ice pellets and water and put it under the window near where my wife was sitting watching television. I came back in. Bottle went off with a nice bang. Wife was so engrossed in her program she never heard it. She asked after awhile when I was going to let off the dry ice "explosion". I said I'd done it, but she was so wrapped up in the BS on the television that she'd been oblivious to it. She went back to her program. I went back to the recycling bin and got a couple of 2 gallon plastic jugs along with a mess of assorted plastic bottles from soda and detergent. The devil was loose in me as I scooped hefty amounts of dry ice pellets into each of the plastic jugs and bottles. In went some water, on went the caps, and I slipped back into the house and went into my office. A few minutes later, all hell broke loose on all sides of our house as I'd planted the bottles and jugs all around the outside of the house. It sounded like a combination of small arms fire and light artillery. Wife and daughter let out a collective scream while I split my sides laughing. I told them that since the first explosion of a 2 liter pop bottle did not get their attention, I upped the ante and mounted a good broadside. Wife called me a few choice names, said my buddies and I were overgrown kids, and said boys seem to like to blow stuff up. She went on about how the fusillade startled her, and I could not stop laughing, damned near pissing my pants. I told her I'd spent a day rebuilding locomotive cylinder heads and was entitled to let off a little steam. I also said it was a shame to waste the remaining dry ice pellets, so was entitled to have a little fun. Wife shrugged and finally agreed.

The local welding supply also sells liquid nitrogen. They rent Dewar flasks to transport the liquid nitrogen in. It is quite a bit colder than the dry ice and makes a real good means of chilling parts for shrink fits. I've used liquid N2 on some jobs for shrink fits, but for the most part, dry ice does the trick.

At one of the hydroelectric plants, we were faced with some large straight dowels which had been driven into reamed blind holes. We had to get those dowels removed as we were fitting a new mating part, and would wind up line reaming for oversized dowels. All the usual tricks were tried to remove the dowels, which, to add to the problems, were hardened (or surface hardened). No "touching" them with a drill, no tapped holes for pullers. I was asked to take a look and see what I could come up with. Discovering the dowels to be file hard, I had the mechanics "spot anneal" the ends of each dowel with a brazing torch. This softened things to where we could drill and tap holes for pullers. The dowels would not move, despite putting a puller with a hollow ram porta power on them. I got a call to come take another look. This was when I suggested the dry ice/heat method. The crew opened the hole in each dowel to maybe 3/4" diameter and then packed in the dry ice chips. They heated a ring around each dowel on the turbine part the dowels were fitted into. I had them give the dowels a few good smacks with a 3 lb hammer, and then put the Vise Grips to the dowels. Out they came. Everyone was amazed at what a little bit of dry ice in the right places accomplished. I had the other ace up my sleeve, and that would have been to get liquid nitrogen and pour it into the holes drilled in the ends of each dowel. The dowels were oriented horizontally, so making some sort of dam or cap to keep the liquid nitrogen in the dowels would have been necessary. The dry ice pellets worked out handily.

As I have learned over the years, a combination of temperature differential and impact will often break a hard fit or bind when heavy force such as from pullers or porta powers won't break things loose. Dry ice is usually available in most cities. The local welding supply, aside from the dry ice and liquid nitrogen, does quite a trade with entertainers who use the dry ice for special effects, and with people who make custom ice cream at parties using the liquid nitrogen. As I've posted here in other threads, I carry the coefficient of thermal expansion for steel around in my head, and often run rough calculations as to how much something will grow (or shrink) for a given set of dimensions and temperature change. I've designed a lot of assemblies that went together with shrink fits, and the force or "hoop stress" which can be developed in a hub or walls of a bore from a shrink fit can be quite significant.

Excellent tricks. It is important to remember that you need a temperature DIFFERENCE, not just an extreme temperature. A story to illustrate:

A knuckleboom loader had lost a couple of teeth from its swing gear. Had to take the gear off to position it to weld the teeth back on. Gear was a foot or so in diameter, and was shrunk onto the hollow, approx 6" diameter vertical shaft or kingpost of the loader. 20-ton hydraulic puller would not budge it. Heated gear with rosebud for an hour and it would not budge. So I got a bucket of ordinary water ice. Set shaft up vertical with the puller under it, pulling gear down. Puller ram pressed against a 1" thick disc that covered the open lower end of the hollow shaft, and I sealed the disc to the shaft with RTV silicone. Pumped up the puller. Set up the rosebud, and started heating. The gear got hot, but the heat conducted to the hollow shaft, too, so although I had plenty of heat, I had little temperature DIFFERENCE.

Then I poured the bucketfull of ice-water into the hollow shaft, and the gear let loose with a BANG! I pulled it off as fast as I could pump the hydraulic pump handle, because I knew that as the ice melted and the water started to steam, and then to evaporate, and as the cooled shaft pulled heat out of the gear, the interference would come back... The interference I measured when all was cool again was .030"

Joe Michaels said:

I told them that since the first explosion of a 2 liter pop bottle did not get their attention, I upped the ante and mounted a good broadside. Wife called me a few choice names, said my buddies and I were overgrown kids, and said boys seem to like to blow stuff up. She went on about how the fusillade startled her, and I could not stop laughing,

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A quick and easy one if you are in an office building is to drop a chunk in the toilet. It bubbles and fumes like a witch'es cauldron and scares the heck out of many people

In a shop, most guys are too used to practical jokes to fall for that

I've seen mention several times of removing dowel pins by heating the exposed ends, it's said that the pins will shoot out. I've tried this several times with no such reaction though.

EmanuelGoldstein said:

A quick and easy one if you are in an office building is to drop a chunk in the toilet. It bubbles and fumes like a witch'es cauldron and scares the heck out of many people

In a shop, most guys are too used to practical jokes to fall for that

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Add a few drops of dish soap to it: you will produce an intimidating mass of gray bubbles. I have done it a few times in the sink of the lab.

Paolo

partsproduction said:

I've seen mention several times of removing dowel pins by heating the exposed ends, it's said that the pins will shoot out. I've tried this several times with no such reaction though.

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I think that the idea there is to expand the air and fluids captured at the bottom of the blind hole where the pin is wedged. It works only if that hole is indeed blind and the pin does seal all around. I think it's a rather dangerous practice.

Paolo

Paolo_MD said:

Add a few drops of dish soap to it: you will produce an intimidating mass of gray bubbles. I have done it a few times in the sink of the lab.

Paolo

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Tried that in college. Didn't work.

partsproduction said:

I've seen mention several times of removing dowel pins by heating the exposed ends, it's said that the pins will shoot out. I've tried this several times with no such reaction though.

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I've heard of something similar where a thru-hole was drilled into the dowel and hydraulic pressure was pumped in to push the dowel out. Stand well back if you do this, as it can come apart with explosive force.

The matter of heating to remove a dowel in a blind hole can be potentially dangerous as was noted. As an example: the camshafts on the old BMW "Airhead" motorcycles (/5, /6, and /7 series) had an small diameter extension sticking off the end of the camshaft. This smaller diameter section passed thru the front cover of the engine with a seal around it. The end of this smaller diameter section had what we call a "D flat" on it, as well as a small male threaded stub (under 1/4" diameter, maybe 5 mm).

The D-flat indexes or establishes the location of the point cam and mechanical advance unit. The small threaded stub at the end of the camshaft gets a nut and washer to secure the point cam/advance unit on the camshaft extension. The problem is people with no real "feel" for the work overtighten the nut on the threaded stub and break it off, or try to roll the engine to set the point gap by putting a wrench on the nut on the threaded stub. Other people had messed up the D-flats on the camshafts by putting pliers or vise grips on to try rolling the engine or for some other crazy reasons. The result is a camshaft which is normally considered FUBAT (f--d up beyond all repair). Until the advent of aftermarket electronic ignitions which take their signal from the crankshaft position, messed up D-flats on the camshaft meant a new (or good used) camshaft.

Bud Provin, whom some of you who ride Airhead BMW bikes may know, had an experience with trying to salvage a damaged camshaft. Bud is a third generation mechanic and has been wrenching on Airhead BMW bikes and old British bikes since he was a kid learning from his father. Bud had read that the extension section of an Airhead camshaft is set into a bored fit in the end of the camshaft with some sort of interference fit. Once it is in there, it is in a blind hole. Bud decided to see if putting some heat on the section of the camshaft which "ringed" this extension section at the interference fit would enable the extension section to be removed. He got more than he bargained for and had a "near miss". Bud put a damaged camshaft in the vise and played a torch flame on the section of the camshaft where the interference fit with the extension was located. He said it did not take much heat, and there was a "bang", along with the extension section of the camshaft flying out, up, and away across his shop. Bud said had he been leaning over that camshaft or been closer to it when the interference fit let go, he'd have likely been wounded or worse. His description was that the camshaft extension "shot out like a bullet".

A more benign example of removing something in a blind hole hydraulically is the removal of an automotive "pilot bushing". The pilot bushing is located in a blind bore in the end of the crankshaft. The input shaft of the transmission has a "pilot" turned on it, and this runs in the pilot bushing. When a pilot bushing is worn and needing replacement, it obviously has to be removed from the crankshaft. If a mechanic is well tooled, he has a puller which wedges out "fingers" which have claws or hooks to get under the end of the bushing- assuming there is clearance between the end of the bushing and the end of the blind bore. If the mechanic is not so well tooled, or there is no room to get the puller in, the old trick is to remove the bushing hydraulically. A piece of steel is turned to a good close fit in the pilot bushing and left long enough to grab onto and also long enough to smack with a hammer. Some grease is put into the bushing and packed in. The driver, which is, in reality a piston, is then put into the bore against the grease. Using a hefty hammer, the mechanic gives the driver or piston a hard smack. The resulting hydraulic pressure usually forces the bushing right out of the crankshaft bore. It's a neat old trick.

In an extreme case, people have freed or broken loose pistons in engines which were frozen using hydraulic force. The pistons are soaked with whatever brand of penetrating oil the mechanics favor- Marvel Mystery Oil and diesel fuel being a popular one, given the quantities needed. The oil pan is dropped (if on a car or truck engine) and the connecting rod big ends are unbolted. This lets one cylinder at a time be freed up. The rockers are removed so all the valves in the engine are closed, while on flathead engines it is a bit more difficult since the tappets may not have enough adjustment to allow valves to be closed if the cam lobes are opening them. Some good old boys would simply braze some fittings to old sparkplug bodies and couple up to grease guns or air grease guns. Others have used old spark plug bodies and connected to Porta Power pumps.

Pascal's Law, like the Laws of Gravity, has never been revised, watered down, or repealed. Hydraulic force is a force to be reckoned with and can be applied to break loose interference fits or frozen parts.

We got a shipment in once, it was packed in dry ice. After we got it unloaded, the driver said, watch this, and carved a little groove in a chunk of dry ice, then put a quarter in it. Pretty soon the quarter started "buzzing" due to the difference in expansion rates between the composition of the quarter. It buzzed for quite a while.

Joe Michaels said:

Pascal's Law, like the Laws of Gravity, has never been revised, watered down, or repealed. Hydraulic force is a force to be reckoned with and can be applied to break loose interference fits or frozen parts.

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That reminded me of this
"Under heaven nothing is more soft and yielding than water, yet for attacking the solid and strong, nothing is better" Tau Te Ching 6BC

I'll give up a trix with dry ice, probably can't do this in front of a safety nazi. The problem with dry ice is you can't just stick it in the freezer and expect it to be there a week or months later. But you can store a bottle of CO2, hose straight off bottle, no regulator, put part to be frozen in a shop rag, fold ends of rag over hose so it creates a bag, and let it rip till you have a ball of CO2 in the bag. Use gloves, googles, hearing protection, crotch shield, whatever makes you feel safe

Can't recall if I mentioned this repair here or on another site somewhere so if I am repeating a story just remember I am an old guy now.

We used liquid nitrogen for an axle on a 70 ton logging mike. Put the axle and hose in a large igloo water jug and put the wheel center and tire in a heat treating oven. The purpose was to have even heat for even expansion. Only heated up to about 225-240 degrees and did not measure the cold of the axle end. The key was in the key way and was also shrunk. Think we left the axle in the liquid nitrogen about 2.5-3 hrs {don't recall exactly}. We gently lowered the axle in the wheel center hole and it went smooth as glass. Zitted and popped for a few minutes as things began to seat.I thought the interference fit as about .001 per inch in our case the fit was .007-.008. The bore in the wheel center had been tapered at time of build in 1912 so it was cleaned up as was the key way and new key. It went so smooth with the first wheel and axle end. We almost screwed things up with a less than stellar set up when we did the other end. The forklift driver dropped the one wheel axle down way to fast and with the weight on the forklift it dropped very fast and hard when it bottomed out. The person in charge bellered at the driver to let it down fast and the driver did as instructed. The blocked up arrangement broke and the whole works tipped but did not tip over and we had safety chains to make sure it didn't. The axle went maybe .25 to far out and we could not see it until after it cooled down and was permanent. It ended up not causing any serious problems but it could of been prevented by cooler heads and better blocking. There was a lot of lateral play that needed to be taken up so it was figured in when assembled, shimmed if you will. The locomotive is running out in Oregon and am told that all is well with it. It ran long enough now that any problems would of arise
by now so our little glitch never amounted to a problem. The point I wanted to make is that while we did not use dry ice we did use a similar process and it worked slick.

We could of pressed them on like some folks do. The concern at the time was potential damage to the wheel centers. A friend of mine was using a wheel press to make wheel sets for freight and passenger cars and used a press. He was nervous about it at first but once he got the swing of how it was done he was ok with it. That is a lot of pressure and if something popped off or broke it could get exciting. But when working with machinery any accident gets exciting. Sometimes you say "boy that was close" other times you call 911. This is a really cool process to use.

Taking advantage of temperature differentials works at all scales. I've removed small rusted-in bolts (the kind we all snap off) from castings by heating the casting with a propane torch then applying one or more ice cubes directly to the bolt. depending on how badly stuck, i'll do this before applying penetrating oil or just go at it with very gentle torque. works great.

The dry ice and alcohol is used for freeze branding animals. Gasoline works as well.

For those of you who are used to fishing parts out of liquid nitrogen need to heed this advice: never try that with dry ice and alcohol! There is no Leidenfrost effect forming a vapor barrier to protect your hand from the cold. Frostbite forms damn quick.

The sad thing is that the games with soda bottles and dry ice can get you arrested in many states today. From Wikipedia:

A law in California that defines "destructive device" includes a list of "weapons" including "[any] sealed device containing dry ice (CO2) or other chemically reactive substances assembled for the purpose of causing an explosion by a chemical reaction".[9][10]
Arizona prohibits dry ice bombs if there is an intent to cause injury, death, or damage to the property of another,[12] as well as their possession by "prohibited possessors" such as convicted felons and illegal immigrants.[13]
In Utah simple possession of a dry ice bomb or similar pressurized chemical reaction bombs is a second-degree felony.[14]
In Colorado, the creation of a dry ice bomb is considered illegal due to interpretation as "possession of an explosive device"
Leaving an unexploded dry ice bomb can be construed as public endangerment.
Exploding a dry ice bomb in the state of Pennsylvania in public can result in criminal charges, as it was not done in an open area such as a bomb range or gun range.

California and Utah law seems to be typically ignorant lawmaking by assuming that the sublimation of the dry ice is a "chemical reaction."

Someone tossed about a dozen" dry ice and sodas" outside a cop station in a bad area.....the cops thought they were under attack from a high powered rifle ,and lay on the floor for 1/2 hr until the swat team arrived.........they were a laughing stock in the force.......the hooligans who tossed the bottles all got a good kicking when the cops found them........there was a rash of explosions here ,,,,soda bottles,car exhaust bangers,and oxy /gas balloons......cops hated turning out to investigate "explosions"and finding a torn plastic bottle.......havent heard one in ages........but I dont think you can get dry ice here any more.

What will be outlawed next ? I am not surprised by California's law against dry ice "bombs", but an surprised that state like Utah, Arizona, and Colorado have laws on their books prohibiting dry ice bombs. Seems like any kind of old fashioned fun is going to be outlawed as we need to be protected from ourselves.

We live in a fairly rural environment and our property is wooded, nearest neighbor is about 1000 ft from our house, so setting off a few dry ice bombs does not bring down the heat on us. In fact, I walk out my door to the edge of the woods, and fire my pistols at a target stand that backs up to a natural earth bank as the backstop.
On New Year's Eve, I have a steam whistle mounted on a pipe mast about 20 feet above the ground, and piped into shop air with an air hose as is used on jackhammers. I blow the whistle at midnight and blow it freely for some time after, interspersed with firing my 12 gauge shotgun at the moon. No one complains and some people say the whistle's sound carries about 2 miles with a dandy echo across our valley. People say that step out of their houses to listen for my whistle on New Year's Eve, and no one has yet complained about my firing my shotgun or firing for target practice outside my house.

Of course, at the rate the laws are being written, the lame brains who are drafting them will soon outlaw oxyacetylene torches because of the hellacious "bang" that happens when a rosebud does not have sufficient flow, or when a large welding or brazing tip "burns back" and snaps like a machine gun. Then, there are the practical jokers who bleed a little oxygen and acetylene into a can or cup and set it off, launching the can or cup with a good healthy "bang". Gotta hurry up and outlaw that as well.

I remember in one place I lived, there was an automobile junkyard where I occasionally bought used parts. The characters who inhabited the junkyard were another story. On warm Saturday nights, these guys would entertain themselves by taking an old truck tire and propping shock absorbers from junked cars in the tire so they formed a kind of "inverted cone" with the shocks radiating from the center of the tire, propped on the tire sidewall so the rod-ends were inclined upward. The guys would get some debris, pile it in the center of tire on the shock absorber cylinder sections, and douse it all with a mixture of gas and oil drained from the wrecks.

They'd throw a lit flare into the center of the shocks and debris and run to a safe distance. There, they would sit on anything handy, drinking "Bud Light" and waiting for the show to begin. The heat of the fire did its work on the old shock absorbers and they would blow apart, launching the rods in all directions and with varying trajectories. This was a big show that they waited all week to put on, and spent the rest of the evening finding where the shock absorber rods blasted to and what damage they did to the wrecks. I never stuck around that junkyard any longer than I needed to be there for getting parts, so never saw the Saturday night show.

In our area, there is a local well drilling firm that has been around a good long while. The founder of the firm is a licensed blaster, aside from having started what grew into quite a large water well drilling and service company. One 4th of July, the founder of the firm and his family and friends were celebrating the 4th in fine style. Across from the well drilling business was an open field, and in that field was where the celebration was happening. The patriarch was cutting sticks of dynamite into halves or quarters, and putting blasting caps in them. They then put those "squibs", as they called them, on the ground and stood empty oil drums with the bottom head removed over the squibs. Everyone got a safe distance away, much yelling of "Fire in the Hole" and then the squibs were set off. The oil drums were launched to considerable height and flew a fair distance in the field. The NY State Police arrived, maybe they'd heard the blasting while on patrol, as it is doubtful anyone called in a complaint. The troopers confronted the patriarch of the well drilling tribe and said he had to stop what he was doing. Reportedly, he said he was doing nothing illegal, was on his own land and well removed from any roads or houses, and was a licensed blaster. The troopers insisted he stop what he was doing, and he challenged them, asking what laws he had broken. That left the troopers scratching their heads, and the old well driller then said: "What are you going to charge me with ? B W I ?" The troopers asked what that was and the well driller replied: "Blasting while intoxicated"- he had been celebrating and was well lubricated at that point. The troopers realized this was going no place, told him to be careful and left.

A co-worker in my old crew, known as "Sparky" after he'd experienced a severe electical shock as a lineman apprentice, claimed he was never the same after that experience. He could no longer work as a lineman, so asked to come into my old crew as an apprentice mechanic. We soon learned that Sparky had a thing for cannons. No piece of large bore/heavy wall pipe or tube was safe if he was around. Sparky had a trout farm on what had been a dairy farm, and he raised trout to sell to restaurants and markets as well as stocking other people's ponds and charging people to come fish in his ponds. He started bulding cannons out of whatever he could find or make off with. His first cannon fired golf balls using some modern version of black powder (Pyradex, I think it is called). From golf balls, he progressed to a a cannon which fired aluminum beverage cans filled with grout mix (sand/cement). This was still too tame, so Sparky got hold of a large bronze bearing shell- a short piece of heavy bronze tube with a flanged end, just right to take an old bowling ball. He built his mortar, and found great delight in firing old bowling balls. I took my children and my nephews up to visit Sparky at his trout farm when they were small kids. Sparky pulled out his mortar with his ATV and set it up. He loaded in the Pyradex and the bowling ball, and the kids yelled "fire in the hole" as Sparky lit the fuse. I made sure we were all well away from his mortar. The mortar and its guncarriage jumped and moved quite a bit from the recoil and the smoke and muzzle flash was spectacular. The kids loved it. We all looked up at the sky to see the bowling ball begin its descent. It seemed to come out of the cloud deck, and I started counting off the seconds. The bowling ball splashed into one of Sparky's trout ponds, made a nice geyser, and a few extra trout got cleaned and sent home with us. I did the math based on the approximate time that the bowling ball hove into sight, and came up with an altitude of 1200 feet above the ground. Sparky was thrilled to hear it.

Sparky turned 50 and his wife made him a blowout party. They had a few full cords of full length logs (trees that had been limbed but not bucked into cordwood) stacked for a huge bonfire. This was doused with diesel fuel and some gasoline was dumped on as well. Darkness came and everyone was eating, drinking and having a good time. Sparky had invited the off duty State Troopers and Sheriff's Deputies to his party, and they were there in force, partying with the rest of us. Sparky ran up the "Jolly Roger" flag and towed out his beer can cannon. He had a new neighbor, up from NY City, who had bought the adjacent property. The neighbor's house sat up on land at a higher elevation, across what had been a cow pasture. Sparky aimed his howitzer at the earth bank at the base of the rise, towards the new neighbor's house. The new neighbor had already told Sparky how displeased he was with Sparky, his trout farm, and all else. Sparky did not drink, never did, and stone cold sober, he was up for some fun. Aided and abetted by a crowd from the powerhouse along with a few other good old boys and the off duty law enforcement, Sparky began lobbing beer cans filled with grout at the toe of the bank which separated his property from his neighbors. The crowd was yelling "Fire in the Hole !" in unison as Sparky touched off each shot. As darkness came on, we all gathered at the log pile and he threw a lit fusee (flare) into it. WHOOOMP ! went the gasoline as the vapors flashed off, and then the diesel fuel caught. In nothing flat, the whole log pile was ablaze. Soon, the bowling ball mortar was brought into action. It got wilder as the evening progressed. On about 10 PM, I loaded up my family and we headed for home.

Come Monday morning at the powerplant, I ran into the resident manager, who was also the town justice in the same town as Sparky's trout farm. The RM was a man who'd bene raised on a farm and started as a janitor in our powerplant. He retired as an exec VP. He had a realistic view of things, and remarked that as town justice, he'd had "one hell of a Saturday night". I asked what went on. He said he'd had an arraignment of a gang of drunks, up from Long Island. Several were buck naked, one had a broken arm and some other injuries and was arraigned wearing a blanket loaned by law enforcement. I asked if this was the crowd from Sparky's party. It wasn't. It was another group altogether. As the RM told me: "Our people know how to party... those other guys got likkered up and were racing 4 wheelers on the public roads... one guy had a head-on with a van and went thru the van's windshield. He was in my court naked with a broken arm and the makings of a concussion. You guys were nothing compared to that rabble. Glad you had a good time."

About the only thing that had to be unofficially banned at the powerplant when I worked there was "potato cannons" or "spud guns". Guys were building them bigger and heavier with larger chambers to hold more volatiles- and charging them with starting ether, propane, or oxygen and acetylene and firing potatoes across an open field within the powerplant "reservation". We had literally square miles of real estate since the plant was a large pumped storage hydroelectric project. While no formal policy ever came down about not making or firing spud guns, the word came down unofficially to please cease and desist. It had reached the point where potatoes were being lobbed well over 1000 feet. No law yet in NY against spud guns, as far as I know. A produce farm in Stone Ridge, NY had a pumpkin cannon they built. It used a few 1000 gallon propane tanks as air receivers, and a tow-behind diesel air compressor to charge them up. The barrel of this contraption was steel pipe, and they used to amuse visitors by shooting pumpkins using blasts of compressed air. I saw that contraption from the road and shook my head, wondering what kind of people would cut and weld on old propane tanks, making major modifications to pressure vessels and then letting the public near it. They used that pumpkin cannon a good few seasons, then sold the farm to another group who had no interest in continuing with it. Just as well.

I am convinced there is a bit of a prankster of hellion in most of us- speaking for myself and my friends. I used to chide my friend Sparky about his cannons, since I am an engineer and have some knowledge of strength of materials and similar subjects. I told him he was going to wind up cut to pieces by the shrapnel when one of his home made cannons let go instead of firing its projectile. His answer was that he was not supposed to have survived his shocking experience (due to a supervisor's ineptness), and he figured every day he lived and was up and around was a bonus. His other answer was that he worked up his charges of the pyradex until he had just enough to launch the projectiles a respectable distance and never went heavier. I replied that he was still taking a risk as each firing of his cannons put the barrels thru a stress cycle and sooner or later, they might rupture when the charge went off. I got nowhere in trying to talk some sense to him. I agreed I enjoyed seeing him fire his cannons as did a whole bunch more people, but it was time to put his toys away. I got nowhere no matter what I tried in the way of convincing him to use his cannons as lawn ornaments. As my wife says, most of us guys never grew up.

I had always thought New York State was a more restrictive state, but from the sounds of it, the states in Wheels17 posts are a whole lot worse. A little fun with some dry ice seems harmless enough, yet the lawmakers seem to have zeroed in on it. What next ?!

I do know for a fact that LN2 does a very passable job of eliminating poison ivy. Early frost and all that.
Not that I've ever done that....

If ya like doin it...its banned.

john.k said:

If ya like doin it...its banned.

Click to expand...

Intesting side story: I work for a Large Blue Computer company and years ago, I had a very nice
man as a boss. Now that summer we had a vistor that was working in our group, and one day this
visitor was explaining (over lunch) how you could take a one liter coke bottle, put a bit of water in it,
and then a bit of LN2, screw the cap on *tight* and toss it in the grass in front of the building, and
it would go off much louder than an M80.

My boss thought about this for a while, and said, Rob, don't do that.

(now my boss was a pretty free wheeling individual, who honestly had not much tolerance
for management nonsense)

Rob proceeded to explain in detail how to do this, how it wasn't dangerous, just made a huge
amount of noise.

My boss stopped in the hallway, turned to Rob, and said:

"I SAID DO NOT DO THAT."

At that moment I realized that a) my boss just displayed true management judgement, and that b) Rob
was a bit dense to not figure out what the potential downside was for my boss, if had gone through with
the plan. Or to put it in the vernacular:

Don't make me have to explain this shit.