Widened out panga

Discussion in 'Boat Design' started by Jim Allen, Nov 23, 2017.

  1. Jim Allen
    Joined: Nov 2017
    Posts: 47
    Likes: 0, Points: 6
    Location: Brandon,florida

    Jim Allen Junior Member

    Hi, I have been a fan of the panga for many years except when it came to the width. I am a commercial fisherman and have used a Carolina skiff for 12 years. I was wondering if you was to take the panga design with the delta pad and just widen it by about a foot to a foot and a half do you think it would cause it to be any less of a panga. To me it would not only be more stable in shallow water but would have a better hole shot with out relying on trim tabs so much. With my objective being how much weight I can carry I also think it would carry alot more weight than its narrow namesake. Any ideas on wether this would work or not would be appreciated. My goal is to take a imported panga and put it on auto CAD so that once widened out, the delta pad would be technically the same just more of it. And then build the hull with a 90 inch beam od instead of the 77 inch that they are now. Thank you in advance
     
  2. TANSL
    Joined: Sep 2011
    Posts: 4,656
    Likes: 87, Points: 58, Legacy Rep: 300
    Location: Spain

    TANSL Senior Member

    Increasing the beam of the boat will increase its resistance to advance and perhaps some aspects such as the trim of the boat when sailing.
    Depending on the shape of the boat, mainly the bow area, you may or may not do what you want or do it with more or less ease. Of course with a CAD program you can create the new model and study the pros and cons before making a final decision.
     
  3. PAR
    Joined: Nov 2003
    Posts: 18,656
    Likes: 386, Points: 93, Legacy Rep: 3967
    Location: Eustis, FL

    PAR Yacht Designer/Builder

    The Panga is a pretty primitive hull form by modern standards. Developed for less than skilled labor and to provide a reliable and predictable performance envelop, it's in need of a lot more than some beam. Instead of making a modified warped bottom do more than it's capable of, starting with a design better suited to your needs, seems the logical course.
     
  4. Jim Allen
    Joined: Nov 2017
    Posts: 47
    Likes: 0, Points: 6
    Location: Brandon,florida

    Jim Allen Junior Member

    I appreciate you response and I haven't seen many hulls that do fit my goals. The panga I've read was designed to run both shallow and in seas as well as the ability to carry large amounts. That is great, however, I need shallow to be around a foot. We do have a design we're our moter is in front and has a tunnel which does fix the shallow water fishing, however, getting into any type of seas is not an option.
     
  5. Jim Allen
    Joined: Nov 2017
    Posts: 47
    Likes: 0, Points: 6
    Location: Brandon,florida

    Jim Allen Junior Member

    Thank you for your reply. I've always thought that the wider the beam the less water is displaced. Or the more water..whatever makes a hull have less draft. So the reason I was thinking about widening the panga was it was designed to run shallow and handle seas while also carrying alot of weight. But at 77 inches I can't see it running in the depth I'd need. However, if it was widened it would seem it would run in less water if it was widened by using cad or a system where it's the same hull just wider..I guess I could study hulls that are made to run in the skinniest water and then see if that would handle weight or seas..thanks again.
     
  6. TANSL
    Joined: Sep 2011
    Posts: 4,656
    Likes: 87, Points: 58, Legacy Rep: 300
    Location: Spain

    TANSL Senior Member

    Could you show some drawing, picture, outline, of the boat that you like with more detailed indication of the modification you need to make?.
    I suppose you have seen enough boats, existing designs, to know that the solution is not in one of them, that you have no choice but to modify an existing one.
    I'm not sure if you want a new design, based on an existing one but with more breadth, or what you want is to buy an existing boat, cut it and expand its breadth.
     
  7. TANSL
    Joined: Sep 2011
    Posts: 4,656
    Likes: 87, Points: 58, Legacy Rep: 300
    Location: Spain

    TANSL Senior Member

    The displacement depends on the total weight you want to carry, regardless of the beam. But, of course, with the same draft and more beam the boat can carry more weight. Or, with the same total weight, if you increase the beam, the boat will have less draft.
    Sorry to tell you these things that surely will be totally obvious, but I do not know the reason you have to want to increase the sleeve.
     
  8. Jim Allen
    Joined: Nov 2017
    Posts: 47
    Likes: 0, Points: 6
    Location: Brandon,florida

    Jim Allen Junior Member

    I'm sorry that I don't know what alot of the terms and verbage you guys use but I understand what your saying. I ran a Carolina skiff 24 and it does run shallow. However, it will beat you stupid in any kind of chop. And compared to other hulls it seems heavy at 2400# hull only. I think the issue of carrying weight isn't a problem but trying to find a hull that runs shallow and is still able to get into some choppy seas without beating you up would be idle. I think a Dory style mite work for my situation except for running shallow. I'll draw how I am set up and then maybe that would help. Thanks again
     
  9. Ilan Voyager
    Joined: May 2004
    Posts: 1,105
    Likes: 63, Points: 48, Legacy Rep: 758
    Location: Cancun Mexico

    Ilan Voyager Senior Member

    I'm living in Mexico, so I'm used to pangas, and I've worked on.
    The pangas originated in Philippines, and Yamaha brought the design in Latin America so the could sell their Enduro series outboards to the local fishermen. The original panga was a narrow 23-25 feet for a 40-50 HP outboard. After it grew up until 33 feet.
    The best in Mexico was the 28 feet with the 85HP Enduro. Pangas are cheap boats for moderate power on good sea, not very seaworthy the Mexican government wisely forbids navigating all boats under 40 feet when the wind is over 22 knots and waves over 2 feet. The quality of building is rather poor but enough for fishing and running in the lw 20 knots on a very nice sea without dismantling the boat.
    Eduardoño in Colombia did the same but a better quality of construction, and developped 35 feet which look like pangas bit are totally different underwater. The need of trim tabs shows that you are overpowered, with/or too heavy engines. Pangas with the right power and good repartition of weight do not need trim tabs.
    I had the example with a dive shop owner of a 33 feet with 2 Yamaha 200 HP. Fully loaded the boat was unsafe, slamming and walking. Empty its bow pointed to the the sky ready to flip over. They tried to correct with trims, that was a useless expense. I changed the 2x200 HP by 2X135 HP with tuned propellers. That took out a lot of weight of the transom and a a lot of gas. The boat fully loaded returned to a normal behavior, lost only 4 knots and halved the consumption of gas. And empty it was not anymore a terrifying thing.
    The funniest thing is that I convinced a sport fisherman to try a modest inboard Mercruiser 6 cylinders 220 ponies with a Bravo 3 (and tuned counter rotating propellers). His boat was the fastest, the surest with its low center of gravity, the cheapest also with the lowest consumption thanks to the fresh water cooling working at 82 degrees celsius, the best temp for a 4 Strokes engine which must run hot to have a good specific consumption.
    I understand what you want but you're going to a lot of complication starting from a panga and widening it. You have plenty of designs that meet you purpose. A very simple monohedron would do the job with an angle keel of 10 degrees at the transom. It's a very simple shape, very cheap to make as it can be done with polyester plates like a plywood boat. No need of a delta pad, good wide strakes are far more efficient to get a better lift with far more stability. A bit more freeboard would be nice, pangas have a too low freeboard.
    I won't talk about the design problems nor the building problems of cutting a hull to widen it. You can easily outperform a panga design with as simple design as the panga but more subtle at the angles of the keel, the water entries, and the 2 strakes (one on each side). And probably it woukd not cost more than modifying an imported panga.
    Have a look on that, you'll learn a lot Fishing boat designs: 2. V-bottom boats of planked and plywood construction (Rev.2) http://www.fao.org/docrep/007/y5649e/y5649e00.htm
     
  10. Jim Allen
    Joined: Nov 2017
    Posts: 47
    Likes: 0, Points: 6
    Location: Brandon,florida

    Jim Allen Junior Member

    Thank you so much for your response. Seems as you know what I'm trying to achieve. Is there any hulls that you would recommend. I use a hull we call a well boat for the shallow stuff and it's a hull with the moter on the bow and has a 4 inch tunnel. It runs very shallow with my nets coming off the stern. Only problem being they don't turn well at all and all weight must remain on the stern..it seems like there are several boat builders that use the delta pad that the panga uses such as Dorado, aquasport, Andros, and a few others. I was thinking the panga is super lite and therefore by widening it you would be able to carry more weight and run shallower while also adding some weight to it. I think for a one person hull using a tiller moter it is a great hull. However, it isn't made for all the stuff that we add..I can't imagine how rough a panga would be riding up front in any kind of seas. I'm hoping to find something that would just allow me to not have to use separate boats
     
  11. Barry
    Joined: Mar 2002
    Posts: 845
    Likes: 38, Points: 28, Legacy Rep: 158

    Barry Senior Member

    [​IMG]
    Tansls comment above Jim,
    "Increasing the beam of the boat will increase its resistance to advance"
    and your comment that increasing the beam will aid in carrying more weight say with the same power. Jim you are correct. Perhaps Tansl was referring to a displacement boat but
    as Pangas are planing, extra beam reduces resistance as it increases the stagnation line length, and the area of highest pressure distribution under the hull.
    At low speeds, say under 10 knots, it is not so apparent
    This was just a hull diagram I pulled off Google images showing the pad and maybe a 15 degree deadrise, just a guess.
    Obviously, the flatter the deadrise, the more pounding that you will get at high speeds and taller waves. Having built 21 - 24 foot aluminum jet boats with 12 degrees being the norm and
    running them in tall standing waves and the ocean in 2 - 3 foot waves, a 12 degree deadrise on an 80 inch bottom is brutally rough. The hull above appears to have a moderate deadrise
    so would be a bit softer in rough water but then it would have more draft.
    So you have to decide what is more important, ride or draft.
    At speeds beyond 15 knots, with a higher deadrise angle, a better ride, bigger draft, with a flatter hull, poorer ride but lower draft.

    Your 90 inch desired beam is quite wide. What length were you considering?
    And, there are manufacturers of Pangas which are using more deadrise than in earlier years. Perhaps they might meet your needs
     
  12. TANSL
    Joined: Sep 2011
    Posts: 4,656
    Likes: 87, Points: 58, Legacy Rep: 300
    Location: Spain

    TANSL Senior Member

    @Barry, according to this phrase I still think that increasing the beam would probably lead to greater frictional resistance and, above all, to greater resistance due to wave formation. As I think it's about modifying an existing design, not creating a new design, I've also said that maybe, depending on the shape of the bow, it's not possible to make the modification.
    If what we are talking about is creating a new project just with a wider path at after area, it is possible (we should do some calculation to confirm it) that you are right in what you say.
    By the way, nice drawing.
    So, increase the beam as the OP wants, is it good or is it bad?
     
  13. PAR
    Joined: Nov 2003
    Posts: 18,656
    Likes: 386, Points: 93, Legacy Rep: 3967
    Location: Eustis, FL

    PAR Yacht Designer/Builder

    I agree, a modest deadrise, monohedren design would make a much better baseline for your new design. As to self designing this, well this just isn't practical, because of the level of hydrodynamics understanding you currently have. Cutting up a Panga will just result in a fatter, draggier hull that will still pound, likely more so in a chop and require more power for the same performance envelop the narrower one enjoyed.

    If outboard powered, you have many choices. If inboard powered, consider a cat or tunnel hull.
     
  14. Mr Efficiency
    Joined: Oct 2010
    Posts: 6,303
    Likes: 132, Points: 63, Legacy Rep: 702
    Location: Australia

    Mr Efficiency Senior Member

    The OP himself more or less concedes himself there is an inconsistency between wanting a boat that can run in very shallow water ( I'm not sure a standard Panga does that, unless some kind of tunnel is incorporated, and the prop is raised up inside or behind it) and still operate well offshore in lumpy conditions. The former is a specialized boat, I doubt it can be adapted to do both well. I dare say a narrow Panga rides a lot better offshore, than one that has just been widened. Wide deep vees can still ride well, wide flattish bottoms just ride worse than narrower flattish bottoms.
     

  15. Barry
    Joined: Mar 2002
    Posts: 845
    Likes: 38, Points: 28, Legacy Rep: 158

    Barry Senior Member

    Say you have an 18 degree boat monohedron , 20 feet long and 70 inches wide, then you merely increase the width to 80 inches wide. So long as you have not added a lot of weight with the extra foot, you will get a hull that for the same power will ride higher in the water, or conversely carry more weight.

    Your term, less frictional resistance, to me this means wetted surface drag which has a smaller impact as compared to pushing the water out of the way as the boat moves forward at planing speeds.

    Width is good

    Unfortunately the OP would like a low draft boat that will pack a lot of weight. He will not get this without a shallow deadrise, ie kidney destroying pounding in big waves.
    If the OPS parameters were given to me I would build a 26 foot by 9 - 10 foot beam, with a 90 - 100 inch chine width, 18 degrees, 4 only 6 inch lift strakes, turned down 6 - 10 degrees down to the horizontal, one pair at the chines and the other pair slightly less than half way in from the chine. I would build it out of aluminum so the weight savings can be turned into cargo carrying capacity and then power it by an inboard jet, a v-8, aluminum headed 5.7 litre EFI engine
    and have it about as good as he can get. If he can afford a bit more draft, then he could run single or twin outboards.( and the 18 degrees can still give a pounding but much better than 12 degrees)

    If he is limited to a towing width, then max the beam and max the chine width.

    A hydrodynamic analysis need not really be done regarding the shape of the hull as if the length of the constant deadrise, monohedron, goes up two thirds of the boat, the boat will ride on the last two thirds or less, planing area, and
    there are thousands of boats in the market that will prove this shape.

    If I was a rookie and wanted to get a idea of a set of lines, a trip to a marina, boat builder have a look at the proven designs.
     
Loading...
Forum posts represent the experience, opinion, and view of individual users. Boat Design Net does not necessarily endorse nor share the view of each individual post.
When making potentially dangerous or financial decisions, always employ and consult appropriate professionals. Your circumstances or experience may be different.