How do I thread a galvanized silo rod?

I pulled down a 50 year old cement silo and saved the steel (galvanized I think) bands. I want to make long bolts of various lengths from them to help strengthen the beams in my old barn. The bands appear to be 5/8 “. How difficult will this be to thread the bands using a 5/8 die? Any suggestions to straighten the bands and thread them are welcome.thanks, Ed

  3 answers
  • Lynn Sorrell Lynn Sorrell on Jan 20, 2019

    Here's bunch of how to do it videos on threading https://www.youtube.com/results?search_query=DIY+adding+threads+on+glavized+pipes Here's some videos on straightening https://www.youtube.com/results?search_query=DIY+how+to+straighten+galvanized+pipes AS with all online info. you'll need to sort thru these & decide what is right/best way

  • Zard Pocleeb Zard Pocleeb on Jan 20, 2019

    I do quite a bit of threading with both taps and dies. To straighten the pieces heat them until they are cherry red then tap them down with a ball peen hammer. Make sure not to flatten them as this will make them unusable. Next remove all rust with a wire brush, grinder affixed with a wire wheel, Naval Jelly, etc. then put them in a vise and cut the threads. Some people say to use cutting oil, some don’t. I have never used it and never had a problem and I have literally cut threads hundreds of times. When you are cutting the threads turn the die wrench forward anywhere from a half turn to a full turn then turn it backwards a half turn to break the chip and clear the die.

    • See 2 previous
    • Ede Ede on Jan 22, 2019

      Thanks again

  • Lifestyles Homes Lifestyles Homes on Jan 20, 2019

    I think this will be difficult to both straighten them perfectly and thread them, unless you have a lot of free time and a work shop. 5/8” is a #5 which is considered “stout”.


    One knows that the galvanized coating is toxic and one wants to avoid breathing the dust or having it their hands.

    One also knows that the galvanized coating, once cut, allows rust to form.


    I suspect the galvanized coating already has pits.

    • Ede Ede on Jan 20, 2019

      Thanks for the advice. The silo rods that I want to cut at various lengths are rusty and somewhat pitted and I do not need them perfectly straight. I do not know how much galvanized coating is left as they are 50 + years old. The 5/8” nuts still can be removed with minor effort . Some by hand only. Should I buy galvanized nuts or regular steel nuts. Thanks, Ede