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Discussion in 'Reverse Flow' started by luter, Sep 17, 2010.

  1. luter

    luter Newbie

    I had this all planned but now am a little nervous. I was origionally told that if a propane tank was filled with water, it pushes all the gas out and is safe to cut because the chemical mecaptain(not sure if that is right) is non flamable and there just for smell. I really don't want any woofs or booms. Anybody know the correct answer to this one?
  2. pineywoods

    pineywoods SMF Hall of Fame Pitmaster Staff Member Administrator Group Lead OTBS Member OTBS Admin SMF Premier Member

    I have heard several people say that too but I haven't tried cutting one yet. I've also heard some people say they used liquid soap with the water.
  3. pit 4 brains

    pit 4 brains Master of the Pit Group Lead OTBS Member SMF Premier Member

    If you vent it out to the point where there is no more LIQUID left, then purge all the remaining GAS and AIR out with water, then you'll bee ok to cut. You can drain as much water need to do a small cut just to settle your nerves. Bottom line is there has to be vapor and some oxygen in there to combust so if you displace it with water, then you are good to go. The propane doesn't seep into the steel and come out later. It will become a vapor at atmospheric pressure so venting the tank for a while will work. You could go so far as to dump a shatload of baking soda in it and then pour in some vinegar. This will produce carbon dioxide and water. When the bubbles reach the top, you are purged of any O2 and can begin cutting..

    The bubbles may not make it to the top but the CO2 will... Put a mouse in a shoebox just above the vent hole, when he kicks the bucket, you have CO2 all the way to the top..
    Last edited: Sep 17, 2010
  4. beer-b-q

    beer-b-q Epic Pitmaster OTBS Member

    Although I have never tried it, I have heard that running a cars exhaust in the tank while cutting will eliminate the chance of explosion because of the carbon monoxide replacing the oxygen in the tank...  It sound reasonable but like I said, I have never tried it.
  5. jirodriguez

    jirodriguez Master of the Pit OTBS Member SMF Premier Member

    I am not sure..... but I bet this guy could tell you how to do it! [​IMG]

    (and yes.... that is the gastank he's welding on!)

  6. raptor700

    raptor700 Master of the Pit OTBS Member

    When I cut my tank, I filled 1/2 way with water put a bottle of Dawn in and filled the rest of the way full with more water. Drained the tank then cut! Had no problems, and I lived to tell about it!![​IMG]
  7. otter

    otter Meat Mopper

    Dont know if this counts but I cut an old alunimun gass bottle , I opened it and vented it for a week , No water no nouthing It didn't go boom
  8. pit 4 brains

    pit 4 brains Master of the Pit Group Lead OTBS Member SMF Premier Member

     Take good look at this photo.. Notice that he only has one wheel chock at the back tire. Whenever you prop up a vehicle with 2x4's placed vertically, always chock the rear tire in two directions for safety sake!
  9. I, like Raptor mentioned, filled the tank with a full bottle of Dawn dish soap. Drained it and filled it up again with clean water. I let this sit for a few days. I drained just enough water out to make my first cut across the top of the doors. Once I started cutting down the door sides I would cut a few inches and let the water drain out of my cut, cut, let drain, cut, let drain...you probably get the pattern now. I still have all of my fingers and toes...for now at least.
  10. pit 4 brains

    pit 4 brains Master of the Pit Group Lead OTBS Member SMF Premier Member

    Why dish soap? Just fill it once with water and get on with it.
  11. rbranstner

    rbranstner Smoking Guru OTBS Member

    No No he has a second one right there His Ankle. If the truck starts to move just shove your right ankle under the tire. haha
  12. beer-b-q

    beer-b-q Epic Pitmaster OTBS Member

    I sure would like to see the next few frames on that camera...[​IMG]
  13. jirodriguez

    jirodriguez Master of the Pit OTBS Member SMF Premier Member

    .... and if you look closely there is a person just off frame to the left (casting a shadow). Personally I wouldn't stand near this guy.... either the trucks gonna crush him, or explode... lol.
  14. diesel

    diesel Smoking Fanatic

    I don't know if you have made the cut yet but if not then here is my 2 cents.

    I filled with water and a bottle of dawn.  Yes Propane will get into the pores of the metal and dawn will bring it out.  Have you ever seen the TV commercial where the grease disperses when the drop of detergent hits the water?  That is why you put the dawn in the tank with the water.  I filled my twice.  Let it sit about a week. 

    Here is how I look at it.  Better be save than sorry.  If you can leave water in there while cutting than that is a good Idea also.

    You can search the forum for this topic.  Others have discussed this before.

    good luck! and show us some pics of the build.
  15. duck killer 1

    duck killer 1 Smoking Fanatic SMF Premier Member

    holy crap!!!!!!!!!!!!  [​IMG]
  16. novasbc

    novasbc Smoke Blower

    I know this is an old thread, but the tank I bought has been sitting for several years with the valves off, and this thread seemed the most appropriate

    Any reason to take additional precautions in such a scenario?

    I can still put water in the tank, but I assume that is just for a tank that has only recently been open to the elements?