Wooden river barge

Discussion in 'Inboards' started by IronTom, Jan 19, 2020.

  1. IronTom
    Joined: Dec 2019
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    Location: arizona

    IronTom Junior Member

    Restoring antique river "scowl". All-wood 18' flat bottom with tiller/rudder.
    Old historian describes river-hauling bales of hay in the winter season.
    The old flat deck is rough-sawn oak planks. Deck foot-locker at bow, held 10 bottles of gasoline??? that looks like whiskey bottles. I better check the old boys story !

    Heavy 3blade 12"brass prop to one-lung engine (which is missing!).
    Weird engine was horizontal mounted inline with the flywheel + driveshaft + prop.
    The piston went up+down, and the driveshaft rotated. Must had some sort of gears.
    Flywheel was toothed for starter, like old Maytag or Cushman engines.

    Problem: The 22" space from deck to keel is too short for a modern engine.
    The proposed engine was a 18HP B&S V-twin electric start... but it is too tall.
    My thought is TWO small Honda 1cyl engines, one on each side of the driveshaft.
    Simple v-belt clutches would allow one or both engines to propel.
    Quiet exhaust thru water-box muffler at stern. Ducted-fan ventilation under foot.

    Question: The giant prop. 12LH14 is bigger than my Mercruiser!
    Can I machine it down to suit the small 8HP + 8HP engines ? Assuming the engines run 2500 RPM, assuming the barge weighs 999LBs including me, you, 1 hay bale, and 10 bottles of 'fuel',,, what prop size would be suited to maintain trolling speed ?

    Any help is appreciated.
     
  2. bajansailor
    Joined: Oct 2007
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    Location: Barbados

    bajansailor Marine Surveyor

    Welcome to the Forum Tom.

    I am guessing that the original single cylinder engine was very slow revving (less than 1,000 rpm?), but it could no doubt develop a lot of torque (especially if it had a reduction gearbox as well?), thus allowing it to spin such a relatively large propeller.
    No matter what engine(s) you use as a replacement, you will most probably need a reduction gearbox to allow you to deliver the required amount of torque to the propeller, if you want to re-use the original propeller.
    Unless you can find another slow speed engine like the original.
    If you machine down the propeller to suit your wee 'high speed' (relatively) Hondas, you will probably end up with an egg-beater that creates a lot of froth, but not much forward motion.
     
    Last edited: Jan 19, 2020
  3. The Q
    Joined: Feb 2014
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    Location: Norfolk, UK

    The Q Senior Member

    Since you are going to replace the engine with something not authentic, how about electric? they are comparitively small, have a good torque and you've pently of space for batteries..
     
  4. gonzo
    Joined: Aug 2002
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    Location: Milwaukee, WI

    gonzo Senior Member

    A 12x14 is not too big. Mercruiser outdrives use 14.5" diameter. There were many old boats without gears. They moved forward when the engine was fired. 18 HP is a lot unless you are thinking of planing. 3HP should be enough.
     
  5. IronTom
    Joined: Dec 2019
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    Location: arizona

    IronTom Junior Member

    Google/found a sawmill powered by a "hit&miss" engine which is near what I pictured in the boat. It surely had a 90 degree gearbox to the flywheel & driveshaft.

    Question; how many RPMs does the big prop require ? 300? 600? 1200?

    The collector rare hit&miss engines are very slow turners, with a lots of torque ( and cost a fortune of $$$ ).
    The closest affordable modern power unit that will fit under the deck is a Chinese motor-scooter. ( ATV & snowmobile ).
    Four stroke, CVT Hi-Lo-Reverse gears, Shaft drive, Water cooled, Electric start, Quiet, 18" tall, over 20HP @ 3000RPM.
    Crankshaft to driveshaft Hi-gear ratio 1:3, Lo-gear 1:6, Reverse 1:8. Easy to install all-in-one unit, under the budgeted $1000 !

    Thanks bajansailor: The prop-shop guru said; Good old prop, and NO, you cannot modify it.
    Thanks TheQ: Consider battery-powered ? The first question from the old boys "you mean like a trolling motor ?" :)
    Thanks gonzo: How did you figure 3HP ? Its 5' x 16' flat bottom. My 5HP putt-putt outboard would make a good anchor !
     
  6. gonzo
    Joined: Aug 2002
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    Location: Milwaukee, WI

    gonzo Senior Member

    I'm still not sure you are talking about a 12" diameter propeller, if you say it is giant. However, 3HP will move a 27' sailboat if there isn't a lot of wind. Your flat bottom punt should move along fine.
     
  7. bajansailor
    Joined: Oct 2007
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    bajansailor Marine Surveyor

    I would agree with Gonzo re just using a simple outboard motor instead - or do you want to restore it to be 90% authentic as per the original?
    (the 10% is re having a slightly different type of inboard motor).

    Do you have any photos that you can post of the boat?
     
  8. IronTom
    Joined: Dec 2019
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    Location: arizona

    IronTom Junior Member

    I was told it must "show its proper age". But,, we do not know when it was made. The last year Sears&Roebuck sold a hit-and-miss engine, was 1939.
    The closest thing I found was a 1925 Louisiana Shrimp 'bateau putt-putt'. That narrows its build date to 1925<-->1939. It could be 100 !
    It was discovered near Yuma Arizona, where the Colorado River crosses into Mexico, where no one is over 100 years old. So much for history.

    The hull is now being rebuilt in a Utah wood-shop (many miles away). The plan is to strip the bottom metal trim & paint. Then fiberglass the bottom.
    The old deck planks and all oak trim are to be re-surfaced. I have all the rudder & prop hardware with best-guess measures of drilled mounting holes.
    The rudder-steering is metal rods from the center rudder shaft to bell-cranks in each corner of the transom. No pulleys or cables.
    A long wood shaft links the transom-bell-crank forward to the steering lever. There is a steering lever on each side of the boat.
    Push either lever forward & back to turn left & right. No idea of how the engine was throttled. There are no seats. I suppose you sit on whatever cargo is on board.
    Most of the deck planks are removable, and there is a lattice "######" floor, so you could sit on the deck with your feet on the floor.
    In fact, you could easily seat eight people for a leisure ride. ( I believe that is what-its-for. The owners live in a lake-side community. )
    Picture a large 18 X 5 X 2 floating box... thats it. I noticed large 2" holes drilled along the gunwales, maybe to secure cargo, or support a roof frame.

    A good neighbor donated a (motorhome) ONAN twin-cylinder generator engine which produces 15HP around a quiet 2000 RPM. Thank you.
    Now I need advice on gear reduction.
    Question; how many RPMs does the 12"dia. X 14"pitch prop spin ? 300? 600? 1200? to cruise around the lake ?

    Hopefully, we'll have photos by summer.
    Thanks - you'all
     
  9. bajansailor
    Joined: Oct 2007
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    bajansailor Marine Surveyor

    I know you suggested that we picture a floating box, but some photos would still be very useful - could you take a few and post them on here please?
    Re how you are going to 'fibreglass the bottom' - is this made from oak planks as well?
    If it is, and you want to try to stay as authentic as possible, would it not be better to keep it how it was? I am assuming that there was caulking between the planks? Simply mentioning 'fibreglassing over timber' is enough potential to generate lots of opinions - as has been done on here before. Do a search re the pros and cons.

    Here is a neat propeller calculator - ok, it is aimed at more 'conventional' displacement hull shapes (rather than rectangular boxes) but you could have a play with it and see what it tells you. It should be able to give a very rough ball park idea as to where you should be.
    Vicprop - Prop calculator for Displacement and semi-displacement hulls https://www.vicprop.com/displacement_size.php
    I tried it with 16' length, 5' beam, 1' draft, 7 knots speed, 1,000 lbs displacement, 16 hp and 2,500 rpm; for a 1:1 reduction and a 3 bladed propeller it gives a 10" diameter and 7.6" pitch.
    A 2:1 reduction gives a 15" x 15" propeller, again with 3 blades.
     
  10. gonzo
    Joined: Aug 2002
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    gonzo Senior Member

    Is the wood shop a boatbuilding shop? Otherwise, the best advice I can give you is to call them right away and tell them to stop. Fiberglassing the bottom is a bad idea. If you are going to fiberglass, then epoxy seal the whole boat. Otherwise, it will cause all kinds of problems, and probably accelerate rot.
     
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  11. IronTom
    Joined: Dec 2019
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    Location: arizona

    IronTom Junior Member

    It would take me a full day driving to Utah, to photo the ugly wood box. Please understand I'm just a free Injuneer:confused: ,,, this is not my boat,,, or $$$$.
    Internet good story: www.fox8live.com/story/17225845/heart-of-louisiana-putt-putt-boats
    Internet photo: https://ralph.lafayette.la.us/stationary-engines/wooden.boat.festival.1999/full/mvc-832l.jpg

    [​IMG]
    Captions: " Whudda heck is it ? " " Em r called a jet skee. "

    I believe the nasty bottom planks had been brush-coated with some sort of rubberized stuff, quickly ruined by the Arizona sun.
    One fellow mentioned "power-planning" and carbon-fiber coatings, as done by the Utah experts that services his rental houseboats.
    Fiberglass was 'my bad' choice of words. The wood will be red-oak-color-stained, and finished with some hi-tech-glossy-poly-stuff that our lungs can't handle !
    Everything under the deck must have approved fire-proof coating. Its a pebble-speckled-gray color 'stuff'.

    The Vicprop calculator is a great assist ! Thanks
     
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