Dumas Sk Daddle Build

[wakeboardfusion]

Started this build the other day. Off to a good start, but it all goes slow from here. This is my first build, so i hope it turns out good!

Here are some pictures of where i am so far, I have put about 1 hour of actual working time in to the build so far.

[alvinsmith75]

My dad built one of these with me when I was young. Which length kit is this? I will surely be following this build and may even start one myself. How do you plan on powering it?
Alvin

[wakeboardfusion]

It is the sk daddle too boat. it is 27 inches long. I was going to buy the smaller one, but will be running in a lake and wanted the bigger one. I believe it was made for a nitro engine, but i will be fiting an electric motor in it. I have a brushless setup from my blackjack that i might throw in to try out, but for now i think i am going to stick with a brushed setup with one 7 cell. By the time i get done with this it will probably be winter, so next season i will be brushless motor shopping. My goal is to get it to run in the mid thirties, and be a stable boat. I dont care too much about speed, just dont want to have to dry all the electronics out all the time.

[alvinsmith75]

The blackjack setup would be awesome in there. You could make plenty of room for batteries as well. Are you gonna make a cover for the motor compartment?

[wakeboardfusion]

Yes, i am going to make a cover for the motor compartment, i am going to try to make a interior for the boat, steering wheel, seats, etc. After a lot of thought, i think my goal is to run in the mid twenties now instead of the mid thirties, it might be too unstable. however, you never know until you try it

[alvinsmith75]

That is gonna look nice. You are right. This hull is just short of being a flatbottom and will need water almost like glass to run smooth. If you want the reliability of brushless, have you considered running the Blacjack setup un either 2 or 3s? If you have 2, 2s lipos for your blackjack, you could run them on 2s2p for double runtime and that should put you in the low to mid twenties.

[wakeboardfusion]

Here it is as of tonight, got the chines on, i am debating on if i need a ... cant think of the proper name right now, but one of the fins that goes in the middle of the boat to keep it from spinning out... I think it might get squirley, but i can always add turn fins to the back

[FE Wannabe]

I too will watch this thread closely as I have a 36" almost flat bottomed hull that I has never been drilled. Mine is supposedly designed after the 1960's Mandella hull design, but looks very similar to your SK Daddle Too.
Are you planning on running a sub-surface drive on this boat or a surface drive setup? With the almost flat bottom on this hull you may get too much prop walk with a surface drive setup, unless you run a big rudder and/or turn fins, but I am not sure. I am thinking of running mine on a 800 sized brushed drill motor for speeds around 20mph or more.

Good luck on your build, it is looking good so far!

Brad

[wakeboardfusion]

The set up I plan to start with for my power plant is a $3 johnson fan cooled motor, I would like to try a 15T or a 12T, but for now want to keep it cheep, and use what I have. I have an old waterproof speed control from an old offshore flyer or a waterproof xl5 to put in there, with DIY water cooling, I also plan to use a traxxas waterproof servo. Not sure what I will use for batts, maybe 7 cell or 2s lipo.

[Flying Scotsman]

Very impressive so far, now comes the hard part is the hull aligned and applying the plywood, balsa then fibreglassing the hull.

Douggie

[alvinsmith75]

Here it is as of tonight, got the chines on, i am debating on if i need a ... cant think of the proper name right now, but one of the fins that goes in the middle of the boat to keep it from spinning out... I think it might get squirley, but i can always add turn fins to the back

I believe the word you are looking for is "skeg". On our SK Jr. build we did not have a skeg but on the 28in. version(just scaled the plans up from the smaller one and made some mods) we did have a skeg. On the bigger hull we ended up running a 3.5 K&B outboard. The skeg will surely keep the boat from sliding in the turns.

[sailr]

You won't double the runtime by running 2S. 2S setups draw more amps than 3S or 4S.

[Fluid]

The set up I plan to start with for my power plant is a $3 johnson fan cooled motor, I would like to try a 15T or a 12T, but for now want to keep it cheep, and use what I have......Not sure what I will use for batts, maybe 7 cell or 2s lipo.

You will not meet your goal of mid-20s with a $3 motor and 7 cells. A 12T or 15T motor will also be a mistake on a hull that size. I understand your desire to save money, but I strongly recommend something like a 700 motor and 12 cells. This will give far better performance and longer run times with cooler temps. I fear that if you use the tiny Johnson motor you will be disappointed in the performance and the run time/reliability. After going to all the effort to build this cool boat (I built several in the early-70s myself) it deserves enough power to get on plane like the 'real' boat did.


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[FE Wannabe]

You will not meet your goal of mid-20s with a $3 motor and 7 cells. A 12T or 15T motor will also be a mistake on a hull that size. I understand your desire to save money, but I strongly recommend something like a 700 motor and 12 cells. This will give far better performance and longer run times with cooler temps. I fear that if you use the tiny Johnson motor you will be disappointed in the performance and the run time/reliability. After going to all the effort to build this cool boat (I built several in the early-70s myself) it deserves enough power to get on plane like the 'real' boat did.


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Jay,

If you don't mind sharing, what were the tricks to getting this type of hull to perform its best? Is this a sub-surface drive only type hull or could it be made to work with a surface drive setup as well? Did you use a straight shaft or flex cable? What size skeg worked best? What were the speed/handling limitations of this design?
Thanks in advance for any input you can provide.

Brad

[Fluid]

When I built them I was running nitro (!) and built the boats as in the plans. It was a straight shaft and I used the skeg size shown in the plans. Props were a problem then because that was before the X-series Octuras were available. I used plastic 1240 and 1440 props if I recall, running an OS .21 engine. Perhaps the lift from those props helped to counteract the hopping.

Mine ran well at the time, or so I thought. Speeds were probably in the low-20s which seemed pretty fast back then. My radio was a used two-channel reed system, no proportional steering - all or nothing. I enjoyed the boats - kinda - since like all nitro boats then they were either hard to start (no electric starters, just a boot lace), or tended to always die at the far end of the lake. At the time with the few guys I ran with it proved to be a good boat though.

I have no idea if these hulls will run well with a surface drive. They might, considering how the gas Crackerboxes run. Mine did tend to trip in tight turns, but with the radio I had at the time it was hard to make a smooth turn. They do bounce like the real thing, but IIRC not nearly as bad as a CBox does. If I was building one today I'd build it semi-scale as in the plans - as an FE of course - and enjoy the limitations of the dated design. I have other hulls which can go really fast if I want that.




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