Keep molds dry

Discussion in 'Electrical/Telco/Grounding' started by Wireless Estimator, Feb 1, 2008.

  1. Wireless Estimator

    Wireless Estimator Administrator Staff Member

    It is advisable to heat up your mold with a propane torch prior to igniting your first weld. If the mold has retained any moisture there is a possibility that it can explode, severely injuring the user. Never use the mold outdoors when there is inclement weather.
  2. Luke Tirrell

    Luke Tirrell Friend of the Community

    Actually, the mold can be used outdoors as long as it is heated first. After that the heat from each ignition will dry any moisture that may have been absorbed. Also the mold doesn't "explode". When there is a great amount of moisture in the graphite, the moisture turns into steam which will escape any way possible, usually through the lid. I am a factory trained expert in Exothermic welding and have been using Cadweld and teaching about it for about 10 years now. If you need any help or info e-mail me.
  3. Tim Kearns

    Tim Kearns Guest

    The use of molds during inclement weather, does however require the tech to take extraordinary precautions. I have a 5" long 3/4" wide scar on my right arm that has reminded me of that for 8 years. While installing a Lyncole 2 layer, rod/mesh grounding system, inside an electrical substation in western NY, during December. After shooting 50 or so of the 72 ground rods with tails, so it could be backfilled and the mesh laid and welded to the tails, it began sleeting HARD, after 50 shots, the mold was still warm, my helper set it on the ground next to him while he cut the rest of the tails. While he did this, I finished cross tying the forms for the grade beams, and shooting them in with the laser, hoping to backfill 18" of the entire site the next morning before concrete, he heated the inside of the mold with a torch before continuing on where I left off, I needed his help for what amounted to about 35 minutes, during that time the mold was clamped to a G-Rod packed and ready to fire. After completing our leveling, he returned to his task, I noticed him standing at the same rod for a good 10 minutes, I walked over just as he stuck the torch in through the lid, being that he could not get the striker to spark, this turned out to be a bad case of wrong time wrong place! Although water will change forms inside the mold, after it has been heated, and is less likely to cause damage, nobody ever explained physics to him, a porous mold with 1/4" of ice around the outside from the sleet, will explode from the extreme temperature difference crossed it's surface, and water vapor expanding in a pours environment.

    I am sure that you did not intend to downplay the increased possibilities of serious injury, when performing this task in unfavorable weather conditions, but it came off that way.

    It is a simple, safe, reliable process when performed correctly, and with well maintained equipment, but a lack of care and proper adjustments for environmental and service conditions, can and will cause severe bodily injury.

    "The absence of Fear, creates a toxic atmosphere of Disrespect."

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