Playing with a hull idea?

[Schiada]

Hello,and I'm new here but been racing for,well a long time. Just not in the small boats.
So, here is a boat that I have put some changes into and was needing to know what class this type boat would run in?

She is 12',should come in at 160#,V bottom and was thinking about using my 40H outboard. Old school wood with old school power.

This is the test 1/4 scale model I plan to test with my R/C motor.









Let me know what you think?
Randy

[Yellowjacket]

Randy,

Very pretty boat, looks like an early to mid-50's kind of design, it reminds me a lot of Hal Kelly's "Foo Ling" or Jinx, and a 40h would be the right motor for that kind of boat.

It would run as a "C" or "D" class boat in the present APBA classes, depending on the motor, but it is doubtful that it would be competitive. It has a lot more frontal area (aero drag) and not as much lift as a current C or D runabout. The modern designs are highly refined flat turning boats, but they aren't pretty, and aren't as useful as what you are designing.

In addition, you probably don't want a V bottom unless you are just using it as a lake racer. If you look at the bottoms of boats currently running, they all have a flat planing surface in the back. Even older designs like the Glenn L C/D runabout have a flat bottomed planing surface with moderate (like 12-15 degree) outer chines.

If you want something that is more race related, you could get some plans from Sorenson for their classic boats (like the Foo Ling and Jinx, or the Switzer Bullett) and use the bottom and stringer design from that with your top sides. Not familiar with the vintage outboard racing scene, maybe somebody who is running there could pipe in, but that's where something like this would be a lot of fun, with a 40h on it, and a flat bottom it should really go.

Also you could look at the bottom shape and design of the "Diablo" that Payson designed as a stitch and glue boat. That boat has a 24" wide bottom that is very similar to racing runabouts of the 60's and 70's and would also make a good vintage runabout bottom. There are some pictures on the GlennL site of their transom and frame design, and also some on the Sorenson site that should give you an idea of what would work a lot better than a V bottom. The Sorenson plans for some of their classic boats would give you something that you know would work, and that's a lot better than trying to start from scratch.

Good luck, looks like fun.

[Schiada]

Thanks for the input Yellowjacket.

She is a cut down/sides of a Flying Saucer from Glen-L. Has a little bottom mod. At 61 it would be ok to run in the back! LOL
Looking for 55 to 60 MPH with luck? All up weight I am looking for will be in the 450# with my fat ass in it.

Calling it a "V" bottom is pushing it,maybe 1 or 2 degrees+-. Wet area at the transom is 38". Should be fast?

Randy

[Yellowjacket]

Very shallow V bottoms like that were popular in the mid-50's, with runabouts like the "Yellowjacket" that Bill Jackson designed and were available as plans in Popular Science. http://svensons.com/boat/?p=HydroPlanes/yellowjacket

That was a fast boat at the time, but it became obsolete with the later designs that Hall Kelly came up with.

With that small a V there isn't any v advantage, it just lets the air trapped under the hull get out easier, a flat bottom with a 24 to 36 inch planing surface and outer chines kicked up is faster. Even the Yellowjacket kicked up the chines at 34 inches of bottom width and that was an "A" class boat running with a 7.5 hp engine. You also want to kick up the chines so that it won't trip when turning.

D stock has a 520 lb weight limit so you will have to ballast if you want to run there.

I'd look into vintage events, that's where something like this should run and be a lot of fun.

[Schiada]

A little more work on it.

Put a scale on the bottom and it will be 32" wet+-. The R/c will have a 7.5cc motor.




Randy