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Dead Men Tales: Cardboard Apps

HeatingHelp Posts: 491
edited September 25 in THE MAIN WALL

Cardboard Apps

In this episode, Dan Holohan reflects on a time when apps were cardboard and contractors were delighted by them.

Listen and subscribe here.

Thank you to our podcast sponsor Supplyhouse.com.


  • Jamie Hall
    Jamie Hall Member Posts: 19,423
    I love that tale! Being an even older fogy, I still have a number of things of that sort around, and texts and handbooks (it's odd. Physics and engineering principles haven't changed much, although materials and so on have). Come and visit someday, if you're ever up this way!
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • EdTheHeaterMan
    EdTheHeaterMan Member Posts: 3,633
    edited September 20
    Does anyone still have the old "Cardboard app" Weil Mclain boiler sizing guide,. that has several cut outs of a house. You would stand across the street and hold up the card and match the size of the cut out that closely matches the size of the house. The bigger the house the more sections your boiler needed. I heard about this from an old-timer (now one of the dead men) when I was younger. I was taking a class on how to do a heat loss to properly size a new heating system. I'm not sure if the old-timer was just kidding or that sizing card was for real!

    Would sure like to see a picture of one if it exists!
    Edward Young
    Retired HVAC Contractor from So. Jersey.
    Services first oil burner at age 16
    P/T trainer for EH-CC.org

  • Larry Weingarten
    Larry Weingarten Member Posts: 2,635
    Hi, That phrase, "smells like knowledge"... for one who used to haunt used book stores, it's evocative! Thanks Dan!

    Yours, Larry
  • mattmia2
    mattmia2 Member Posts: 5,997
  • Dougo
    Dougo Member Posts: 7
    I had a boss at Slant/Fin who gave me a System Syzer. Best thing I ever got. Loved this story Fan!
  • Dougo
    Dougo Member Posts: 7
    I meant Dan!!
  • DanHolohan
    DanHolohan Member, Moderator, Administrator Posts: 16,093
    Thanks for listening! I had fun with this one.
    Retired and loving it.
  • Labenaqui
    Labenaqui Member Posts: 59
    Still have my Dad's, and mine ..... along with my "Skid Rule" aka Slide Rule.
  • The RadPad is the last "Cardboard App" that I got and it is very handy even if it's only used for showing the relationships between circuit length, pressure drop, output, water temperature and floor covering. Haven't seen any new ones since.
    Often wrong, never in doubt.
  • PRR
    PRR Member Posts: 59
    > I think of as cardboard apps. These are the sizing calculators...
    All engineers (degreed or not) used various slip-sticks. Earlier this year a bunch of electronics workers on a forum were geeking-out on old-times: Using the slide rule...
    > Haven't seen any new ones since.
    They are still being made! Some of the old favorites, or anything you want custom (if you buy hundreds+).
    Since 1934:
    That company informs us the fancy-name for "paper-apps" is volvelles.
    Over 60 years:
    HVAC: Air Duct Slide Rule Calculators
    HVAC: Air Duct Wizard Ductulators
    HVAC: Duct Design Calculator Wheels
    Concrete & Masonry Materials Estimators
    Pregnancy Wheels
    Google suggests these are the same building; perhaps two operators who consolidated as markets shrank.

  • GGross
    GGross Member Posts: 244
    Contractors would still love to have an array of "cardboard apps" Many still use cardboard duct calculators, and I run out of the cardboard gastite sizing guides whenever we get more in. Those are the only two we are ever offered from any manufacturer. Contractors love them , you really can't beat the convenience of information access like that on a dirty jobsite where you might just not want to keep your phone around or don't have any service.
  • mattmia2
    mattmia2 Member Posts: 5,997
    Of course that method of sizing gas piping will almost always result in bigger pipes than you need...
  • GGross
    GGross Member Posts: 244
    Eh, maybe. I have checked against the code book a couple of times and it never oversized me yet. I am also of the opinion that if you are pushing the limit of that gas line you might as well just size it up once, your customer will be grateful when they go to add something on later or what has been happening recently here with everyone switching from LP to Natural. Sizing down that gas line didn't really save Mrs. Jones any money when she had to swap out all her gas lines 13 years after her home was built to switch to Natural gas.
  • jeant
    jeant Member Posts: 20
    Dear Dan,
    The cardboard apps is a very apt name, I like that. Using them always reminded me that some else a long time ago created these wonderful handy tools for all of us to use. Made the work to figure things out, a lot less over whelming at the time. Nice to have something so dependable.
  • heathead
    heathead Member Posts: 205

    Thank you. I was trying to think of the name RadPad for Pex piping. That is one I would like to find a cardboard version. It looks like the have it online, but the cardboard would be just nice to have. I keep checking on eBay from time to time but no luck.
  • @heathead PM me your address and I'll send you the one extra that I have.
    Often wrong, never in doubt.
    Larry Weingarten
    HEATSPEC Member Posts: 7
    "Cardboard App" - what a great name! You oughta trademark it.
    Still got my old Ductulator and Enthalpy Chart gathering dust on a top shelf, somewhere.
    But my FAVORITE "Cardboard App" is the old "Nick Manoloff's Chord Chart" that came with my Mother's old Montgomery Ward guitar [the one with the hula dancer and palm trees stenciled on it]. I've since moved on to better instruments, but the revolving wheel chart, complete with finger tablature, still comes in handy figuring transposing chords. Now if I only had time to play, nowadays......