Mark's PH18 in Toronto

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MarkOrge
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Re: Mark's PH18 in Toronto

Post by MarkOrge »

Guys, I saw mention somewhere of the diminished need for spashwell with the use of jackplates. I see some that have eliminated the well altogether like Bassmun's. What is the cost/risk of this? I was planning on making my mold to come out similiar to his.

Mark
My Son calls me "The Fish Whisperer" I love it !

TomW
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Re: Mark's PH18 in Toronto

Post by TomW »

As long as you have room to tilt the motor with the jackplate a splashwell isn't needed. However you still need the framing in some way to provide the strength for the transom. You can use the compartment for a livewell or storage or something else. Take a good look at how Bussman used his.

Tom
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tech_support
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Re: Mark's PH18 in Toronto

Post by tech_support »

you have to know the motor cowling size. You can estimate this pretty closely by making a scaled drawing.

Joel

MarkOrge
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Re: Mark's PH18 in Toronto

Post by MarkOrge »

Say, how does one determine the weight distribution?

This is going to be a bassboat with a jack plate. As someone pointed out earlier, I'll need to offset effects of the jackplate, what about trolling motor batteries? These are the major differences. The trolling motor itself is at the front and body weight is forward of the normal center console seating by about 18". The major decision left is where the fuel goes. Speaking of which, does everyone ever venture to put the tank below decks? This sounds risky as you would be doing some major cutting and subsequent repairs if you ever had to get it out. There is a difference between "access" and "remove-ability".

Thoughts? Is there a formula for accounting for all the pounds and where they reside? (that would not be so tough)

Progress: flat panels (bulkheads) are almost done and I am ready to get stringers laid up, hopefully this weekend. Then I'll have something worth sending pictures of.

Congradulations to all the other builders, I have been regularly skulking the progress all summer....mostly the PH18's of course....
My Son calls me "The Fish Whisperer" I love it !

MarkOrge
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Re: Mark's PH18 in Toronto

Post by MarkOrge »

http://gallery.bateau2.com/displayimage.php?pos=-33399

Here is a link to a .pdf that shows all kinds of detail (likely too much) that may help with weight distribution answers....the deck looks particularly cluttered as it has hatch drains, lids, etc. all drawn in (will come in handy shortly when I start the deck mold)
My Son calls me "The Fish Whisperer" I love it !

MarkOrge
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Re: Mark's PH18 in Toronto

Post by MarkOrge »

Anyone?
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gstanfield
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Re: Mark's PH18 in Toronto

Post by gstanfield »

Your drawing is nice and while I don't have a clue about how exactly to balance it I would imagine that you'll need more weight foward like moving the 24V battery bank up front. Without knowing the boat it looks like too much heavy stuff int he back and not much weight up front at all.

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flyfishingmonk
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Re: Mark's PH18 in Toronto

Post by flyfishingmonk »

Hi Mark,

I'm now following your thread and am building a PH18 down here in TX. I look forward to conversing with you on your thread.

I havent looked at you drawing yet but can say I have talked this over with others and I'm starting with my trolling motor batteries under the center console. I will move them under the front deck for ballast if necessary. Under my front deck will be two 13 gallon tanks as well, so I'll have to separate them. My boat will have the trolling motor (2 actually) mounted to the trim tabs.

I say all this to basically state that I am trying to evenly distribute out the weight.

Casey
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TomW
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Re: Mark's PH18 in Toronto

Post by TomW »

Hi Mark missed your original question. First assume that the boat is balanced as drawn by Jacques with the specified motor on. I think this is a 90HP. Then take a measurement along the designed water line. Again I believe this is 6". Now from the transom mutiply along this line 42% of the overall waterline and mark it. That will be the Longitudinal Center of Gravity.

Now let's say you move the motor back 6" from where it is on a Jackplate. 6" or .5' times the weight of the engine moves the LGC back 400 x .5 or 200 lbs. That means that you must move 200 lbs forward of the LGC so say the trolling motor weighs 70 lbs and it is 10' forward of the LGC that is 700lbs. So you must move some weight back. So now you have 500lbs to counter balance. So you put your bait tank in the rear which weighs 200lbs 3' behind the LGC and you are now within 100lbs of being balanced so you put the batteries in the console and your totally balanced.

I am being a little silly here as it will never work out quite that well but if you can get within a 100-150lbs your doing good.

The best thing to do is to do a spread sheet. I did one when I took the C17 from the cabin to an open boat and it is the way Jacques does when he designs a new boat. But it works, has since my first design courses in the 70's and how Jacques was taught and still works now.

As far as the gas tank buy a quality aluminum one that you can put under the console and forget about. These folks will build you a tank that fits your area and ship it to you! It is coated and ready to install. http://www.speedytanks.com/ My tank will fit under the sole but the fittings will be in an enclose area under the console and seat above the sole. The fuel filter/shut off, fuel sensor, and pump to the engine will actually be under the seat.

Tom
Good fishing and red skys at night sailors delight
C17ccx, Mirror Dinghy

MarkOrge
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Re: Mark's PH18 in Toronto

Post by MarkOrge »

Thanks you guys!

Tom, not silly at all - that is EXACTLY what I was looking for. I was at a loss as to how to calculate balancing. :D

Casey - what part of Texas are you in? My head office is in Austin and I have to be there at least 3 or 4 times a year, usually all week.
My Son calls me "The Fish Whisperer" I love it !

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