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Oct 31, 2011, 12:43 PM
Sea Dragon-Lover
Umi_Ryuzuki's Avatar
Been a long haul, but it's coming together nicely.

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Nov 01, 2011, 03:48 PM
Mopar Musclecar fanatic
xx29l9's Avatar
[QUOTE=Umi_Ryuzuki;19746392]Been a long haul, but it's coming together nicely.

[/QUOTE

Are you saying I'm slow... I only started this thread 596 days ago and just recently have something that resembles a hull. Looks like I'm right on schedule...

I did swing by West Marine today and pick up some of their epoxy resin just to have it when I'm ready.
Nov 02, 2011, 11:24 AM
Mopar Musclecar fanatic
xx29l9's Avatar

Thinking ahead. Again.


While waiting for some wood filler to dry, I thought I better start to see how things will physically fit in the boat. Looks like my guesstimates were about right. There is room for 2 battery packs under the cushions on each side. The motor in the pic is a 550 sized brushed. I am leaning towards a brushless motor to help save space. According to the scale power formula posted by CG Bob in another thread, I need about 151 watts for the model. Which means I will probably look at something in the 400-500 watt range. I will not build an under powered boat! The worst question I could hear "is that all the faster it goes?". I don't feel like trying to explain scale speed to someone. Easier to run at half throttle then try to to re-power later for more speed. Will probably go with 2 LiPo battery packs in place of the NiCads in the pic.
Nov 07, 2011, 01:14 PM
Mopar Musclecar fanatic
xx29l9's Avatar

Don't need a ruler-


The next time I can use a ruler to draw a straight line to be cut out will be the first. So far, nothing on this boat is straight, everything has some kind of bend, twist or combination. Keeps it interesting I guess. I cut out and worked on 2 pieces of wood that form the base for the windshield to be mounted on. It may not look like anything special, but the pieces have some complex shaping on them. Awhile back I mentioned adding to triangle pieces under the upper deck piece to provide the correct slant to it, well now these pieces try to cancel that out so the windshield will be a continuous flat edge on its bottom. The outside curve is the thickest point and the wood was sanded thinner as it goes both towards the middle and down the side. And the outside edges are beveled for fun. Also marked out and cut the slots for the fresh air vents, not sure if I will make these actually functional on the model. Maybe, we'll see.
Nov 09, 2011, 11:44 AM
Mopar Musclecar fanatic
xx29l9's Avatar

The eyes have it


Here I go again, can't leave well enough alone. If I was to go back to day one on this build, here is a change I would make. The rib that sits right under the windshield has a shape that pushes the chine a little lower than it should be by the time you bend the wood around it. Instead of a smooth line from the bow sweeping down the side of the boat, it has a slight bump in it...Probably could have left it alone and only I would have known. But the more I thought about it I wondered with the model was running at a fairly fast speed if this bump might cause some porposing? That and the fact it was driving me crazy again the more I looked at it made me do something about it. Got out the masking tape and used it to put a new line down the side that I can use the Dremel sander on to bring it to where I want it. Luckily there is plenty of wood in that area to sand on. This will be done on both sides.
Nov 11, 2011, 12:17 PM
Registered User
whoa... that is awesome!
Nov 11, 2011, 12:55 PM
Mopar Musclecar fanatic
xx29l9's Avatar
Quote:
Originally Posted by mk2driver
whoa... that is awesome!
Thanks mk2! I don't have any pics this morning, but last night I revved up the Dremel and got rid of those annoying bumps on the chines. Wow, glad I did that as it changed the look for the better. I'm mucho pleased.
Nov 11, 2011, 04:07 PM
Boaters are nice people.
Quote:
Originally Posted by xx29l9
The worst question I could hear "is that all the faster it goes?"
Hi xx29l9,

As result of the rather steep propshaft angle, the answer to that question may very well turn out to be: "yes".

Installing too much power will push the bow down (or the stern up) making the boat run very wet and slow, while the motor will draw a lot of amps.

I only just stumbled upon your build, otherwise I'would have warned you (much) earlier.

Going fast with a modelboat requires a propshaft angle that's as shallow as possible.
This means either using a very long shaft, and the motor way up front under the foredeck, or using a flexshaft, which will allow you to run the shaft parallel to the keelline.

My personal objection to using a flexshaft in a semi scale model is the necessity to pull the flexshaft after every day of running the boat, to dry it and re-grease it.
Failing to do so will cause the shaft to rust solid in a matter of weeks...(or days, if you're running in salt water).

Regards, Jan.
Nov 11, 2011, 05:11 PM
Mopar Musclecar fanatic
xx29l9's Avatar
Quote:
Originally Posted by pompebled
Hi xx29l9,

As result of the rather steep propshaft angle, the answer to that question may very well turn out to be: "yes".

Installing too much power will push the bow down (or the stern up) making the boat run very wet and slow, while the motor will draw a lot of amps.

I only just stumbled upon your build, otherwise I'would have warned you (much) earlier.

Going fast with a modelboat requires a propshaft angle that's as shallow as possible.
This means either using a very long shaft, and the motor way up front under the foredeck, or using a flexshaft, which will allow you to run the shaft parallel to the keelline.

My personal objection to using a flexshaft in a semi scale model is the necessity to pull the flexshaft after every day of running the boat, to dry it and re-grease it.
Failing to do so will cause the shaft to rust solid in a matter of weeks...(or days, if you're running in salt water).

Regards, Jan.
Hi Jan-
Well...I hope the scale hull performs close to the 1:1 hull. I'm not looking to set any FE speed type records with this model, but I think I should be able to hit 15-20mph with the right combination of motor/prop. The shaft angle on the model turned out to be the same as the 1:1 due to space constraints. The 1:1 boat is no speed demon either considering the horsepower it has. It's geared and propped to pull people out of the water and get to wakeboard/water skiing speed quickly, not high top end. I look forward to water trials (someday) and see how this all works out. The boat is really light and I will have lots of room to move weight around and it will probably take a fair amount to put it at the proper waterline. Thanks for looking and helping me pay attention.
Nov 11, 2011, 11:15 PM
Model trains, Rc Boats, Rc air
You need to make a raft to put behind the MALIBU.
Nov 14, 2011, 11:52 AM
Mopar Musclecar fanatic
xx29l9's Avatar

sand and fill sand and fill....


Wood filler and sanding, over and over. That is the rule for the last week. I did start adding a raised trim piece on the top of the sides. There will also be a trim piece added to the bottom of the sides next. Which leads to more sanding, more wood filler and repeat.
Nov 14, 2011, 12:38 PM
Boaters are nice people.
Quote:
Originally Posted by xx29l9
Well...I hope the scale hull performs close to the 1:1 hull. I think I should be able to hit 15-20mph with the right combination of motor/prop. The shaft angle on the model turned out to be the same as the 1:1 due to space constraints.
Hi xx29l9,

As the water isn't scaled down like the model, it's always going to perform different, hence the need to adapt the model to it's working environment.

Changing the propshaft angle to as shallow as possible is one of them, adapting the underwater hull, so the model will actually get on the plane, is another.

Not knowing the original boat 'in the flesh', I can't tell you if the underwaterhull needs to be altered, see how she runs.

The propshaft angle may be an issue, pushing the bow down can't be counteracted with the distribution of weight, as each boat has a CoG you can't mess about with too much, without ruining the running attitude.

I'll keep an eye on this thread to see how you fair, once it hits the water.

Good luck!
Jan.
Nov 21, 2011, 11:49 AM
Mopar Musclecar fanatic
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More side trim


Both sides now have the raised trim on the lower sides below the rub rail. I still need to finish the stern portion of this trim. Kind of hard to see this raised area in the pictures, but it will stand out once painted like the 1:1 boat. Base for the rub rail will be next.
Nov 21, 2011, 02:26 PM
Model trains, Rc Boats, Rc air
Looks great
Nov 28, 2011, 11:45 AM
Mopar Musclecar fanatic
xx29l9's Avatar

Working with sintra-


Not a lot of model time over the holiday. The youngest son and I did pick up some wood and build another workbench in the garage for the miter saw and router. Good times. On the 'bu model, I did take some 1/8" square sintra rod and bend and glue it around the boat for the base of the rub rail. Turned out good and the sintra bent around the corners easily. First time I really worked with the stuff.


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