oversized prospector or oversized ranger... which one?

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pyrofly73
Posts: 30
Joined: Mon Nov 30, 2009 8:54 pm

oversized prospector or oversized ranger... which one?

Post by pyrofly73 »

Hi everyone,

I am struggling trying to decide between 2 of the designs in the Canoe Craft book. For me this is a serious investment of time and money and I really want the boat I choose to fit my needs in the end.

The two boats in question are the “Ranger” and the “Prospector”. Neither of these boats is large enough to fit my needs as designed.
I do not simply want to space the molds further apart as I want to keep the design of the canoe intact. Instead I am thinking of increasing all dimensions an equal percentage.

My dilemma is this….

1. Increasing the size of The “Ranger” by 15% would give me length of 17’ 3”, a beam of 40.5375”, and a depth of 15.525”. Increasing the size of The “Prospector” by 10 % would be length of 17’ 8-1/4”, beam of 38.5”, and a depth of 14.575” this leads me to believe that the “Ranger” will carry more load and the “Prospector” is a faster boat with less carrying capacity?

2. Is there an easy way to guesstimate what the carrying capacities, draft, and the weight to immerse additional inches for the increase sized vessels?

3. Do you see any potential problems with increasing the size of the vessels or will they require additional reinforcing(ribs glass or thicker strips)?

4. Is one of the 2 designs clearly better for any particular reason?

5. What would you say is the best way to increase the size. Increase the numbers by a % and then loft, or loft as designed and then take full sized drawings to a blueprint place to enlarge by 10 or 15%?

thank you for your answers.
Rick
Posts: 727
Joined: Thu May 27, 2004 9:23 am
Location: Bancroft, Ontario

Post by Rick »

2. Is there an easy way to guesstimate what the carrying capacities, draft, and the weight to immerse additional inches for the increase sized vessels?
My guess is the carrying capacity would increase as the cube of the increase in size.... eg, for an increase of 15%......... 1.15 x 1.15 x 1.15 = 1.52

Carrying capacity should increase by about 52%.

Why not just build a Nomad... a canoe with a beam of 40 inches will probably create problems with paddling comfortably, and it'll be slow especially in wind. Unless the paddlers are extremely large individuals, it's probably better to stretch the Prospector as canoe manufacturers have done. There are Prospectors in 15, 16, 17 and 18- foot lengths.... the all have the same beam.
willo
Posts: 156
Joined: Sun Jul 15, 2007 12:48 pm
Location: Echo Bay ON.

Post by willo »

I agree with Rick , a stretched prospestor would give you a lot of capacity. You will likely change the characteristics of the boats by just super sizing them in every direction. a Ranger is fairly flat in the center , so a beam of 40" might be pushing it for 1/4 " strips. If your cocerned about the investment of time and money you might wan't to build a design that has known results, there have been a lot of stretched Prospectors built with great results.
pyrofly73
Posts: 30
Joined: Mon Nov 30, 2009 8:54 pm

It's time to number crunch.

Post by pyrofly73 »

Rick,

That is a very good guess!!! Yesterday I also sent an email to Steve Killing before I posted on the forum.. I did not think I would get a reply, but was very surprised that this morning his answers were in my in-box. These where Mr. Killings answers(they where all in caps so they would stand out against my questions).

1. YOU NEED TO DECIDE WHAT IS THE PRIME GOAL OF THE BOAT. DO YOU NEED STABILITY, CAPACITY, OR SPEED. WITH THESE MODIFICATIONS SPEED WILL NOT BE YOUR GOAL, THESE BOATS HAVE TOO MUCH BEAM TO BE VERY FAST.

2.? AS YOU INCREASE ALL DIMENSIONS BY 15% THEN THE CAPACITY WILL INCREASE BY 1.15X1.15X1.15=X1.52. WEIGHT TO IMMERSE WILL INCREASE BY 1.15X1.15=X1.32. IF YOU LOAD THE BOAT TO THE SAME WATERLINE, OBVIOUSLY THE DRAFT GOES UP BY 15%.

3.THE STRUCTURE OF THE BOATS SHOULD BE OK

4.VERY SIMILAR DESIGNS.

5. I WOULD INCREASE THE OFFSETS AND THEN LOFT FULL SIZE.

I think this new info is great and I sent him a thank you email already.

For the most part my paddling will be in Everglades National Park. I need a canoe that will carry a whole lot!!!

There is no drinkable water (We typically take 4 gallons frozen in the cooler and 6 gal in a Jerry can). 90lbs in water alone.

I am not a small guy 6' and 230lbs and my wife isn't a light weight either 160lbs.

We normally use an outboard as the wind and tidal flow can make you go backwards while paddling forwards. 3 gal gas + motor weight. 100lbs

tent, stove, food, fishing rods, food, MOSQUITO SPRAY, etc etc. It adds up really quick.

1 foot chop is very normal in the big bays and when exposed along cape sable in the open Gulf of Mexico. A high free-board helps big time.

Most people we have seen out there use Plastic canoes from Old town. The specs for the most common models are below with the increased canoe craft designs for comparison.

Tripper 172 Discovery 169 Ranger Prospector
up by15% up by 10 %

.Length 17' 2" / 5.2 m 16' 9" / 5.1 m 17.25' 17.6
Width 37" / 93.9 cm 37" / 93.9 40.25" 38.5"
Width at 4" Waterline 35.5" / 90.0 cm 35" / 88.9 cm 38.75" 36.5"
Bow Height 25" / 63.5 cm 23" / 58.4 cm 25.3" 21.75"
Depth 15" / 38.1 cm 15" / 38.1 cm 15.25" 14.575
Weight 80 lbs / 36.2 kg 85 lbs / 38.5 kg 70lbs guess? 75lbs guess?
Max Load 6" free 1,550 lbs 1,400 lbs 1440lbs 1300lbs


The 40" width on the up sized Ranger is the only number out of whack.... How bad is a 40" wide canoe anyway?j To get this dimension correct It looks like i might have to increase by a smaller percentage to bring the width down to a manageable level and then stretch out the molds to get the right length.

The prospector could use a higher bow to help with the chop this will basically require redesigning the boat. No GOOD

The Nomad was a design i had not considered since it is not in the canoe craft book. Looking at the specs I think it could be a little wider to help with the off center weight of the outboard. It does seem to be the closest one to what I'm looking for. I think it will be the back up plan if i cannot loft the ranger to my liking..

Thanks for the input.

anyone else have some input?
pyrofly73
Posts: 30
Joined: Mon Nov 30, 2009 8:54 pm

Post by pyrofly73 »

Willo,

If i stretch out the prospector to 17.6' and leave everything else the same... here's what i get.

weight to immerse 120lbs lbs/in X1.10= 132lbs/in

displacement 420lbs x 1.10 = 462 lbs.

in other words 462lbs takes me up to 4" waterline on the new design

3.25 inches are available to sink the vessel and maintain 6" free-board.

3.25 X 132lbs + 462 = 891 lbs max load at 6" free board.

891 lbs
minus

360 lbs our weight
90lbs lbs water
100 lbs engine, mount and gas

equals
341lbs left for
stove, tent, sleeping bags, sleep pads, lantern, clothes, fishing gear, binoculars, vhf, gps, cooking gear and utensils, first aide, consumables.

We normally do a minimum of 5 days out there. So the little things add up, especially since we enjoy fresh foods fruits veggies, beer. ( the cooler 72 qt is full)

This brings us very close to the 6" mark and we definitely do not want to be anywhere near that.

I understand where you are coming from about sticking to a proven design. that was my intent by increasing all dimensions equally not just length.

I also was concerned about increasing the size of the boats without increasing the size of the material they are built from , but Mr. Killing answer said it should not be a problem. In any case I will probably go with 2 layers of 6 oz glass on the bottom and a graphite/ high density filler/ epoxy coat for scratches on top of that. I know this will not be a light boat, but am sure i will be within range of a royalex canoe. I am also not completely against the idea of adding a rib or two. on the inside to prevent "oil canning"

thanks for your input
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