61 inch Down East/Sport Fish Hull - Page 3 - RC Groups
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Dec 12, 2008, 04:50 PM
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time4420's Avatar
I just sanded down the first layer and did some shaping. I don't do much quickly.
I'll apply the next coat of filler tomorrow.
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Dec 12, 2008, 04:58 PM
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that is going to be a great looking boat when done!
Dec 12, 2008, 05:45 PM
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time4420's Avatar
Thanks Aero.
How would you power a boat like this? Would a couple of johnson 970's be enough for scale speeds?
I was just looking at the Mack 1885G's. Does she need to be geared? What about props?
Do you guy's pitch your own props?
Sorry for all the questions but I don't know much about model power. I need lot's of help.
Dec 14, 2008, 06:46 PM
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not to thread jack, here is my big downeast hull



https://www.rcgroups.com/forums/showthread.php?t=938540
Jan 10, 2009, 06:36 PM
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time4420's Avatar
It's been a while but here is the plug to date.
The middle pic is before the lengthened keel which will be trimmed at different lengths, for single or twins.
The keel will be hollow so the boat can be ballasted in the case of single screw with the ballast very low in the boat. I think this will be a 1/8 or 1/4" cored hull. Very strong and light weight.
The taffrail (top of the transom) will be slightly convex. It hasn't been trimmed yet.
I should have a hull in 2 or 3 weeks. Good amount of work still ahead.
Last edited by time4420; Jan 10, 2009 at 06:47 PM.
Jan 10, 2009, 09:40 PM
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lookin good Dennis.
Jan 12, 2009, 07:04 PM
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time4420's Avatar
Thanks CME,
Here she is after I sanded down the stbd side today. Time for the next coat of filler!
Port side layer is half way sanded.
There is the motor!
May 24, 2009, 07:56 AM
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Ok...I'm ready to pull the trigger on two ESC's for my two Johnson 970's that will be fed 12V.
I'm looking at the Mack waterproof esc for 40usd. What do you guys think?
I don't want to spend 200usd but I want a good control.
The plug is nearly done(I have gotten swamped with work so progress is agonizingly slow right now)and I'll post pic's tonight.
Dennis
May 24, 2009, 02:43 PM
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mxz70017's Avatar

Sounds like a good plan..


Price for those ESC sounds great.Cant beat water cooled with a fire stick!!!Looking good.Hey an atleast you have work... like myself In the trades at this time you should consider yourself lucky!!!
Dec 06, 2009, 04:47 PM
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time4420's Avatar
The hull is 61" with a lobster style underbody with hard chines. 2 970's at 12V 5,000 rpm 1/4" shafts.
Props are Ribavo 70 mm 4 blade 5,000 rpm. Running gear is from the Dauntless kit. 3/16 shafts. Small Parts u-joints 1/4 to 3/16".
My rudder servo is the Hitec HS805BB.
Speed controls are the Traxxas XL-2.5.
The boat will be completely watertight so I will have to water cool, right? Is this possible?
Dec 06, 2009, 05:07 PM
Mmm, tugs...
patmat2350's Avatar
??
Watercooling is only needed for racing motors and ESCs which are pushed to and beyond their normal limits... and for scale motors that are mismatched to their props. Don't know about your set-up... but it should always be possible in scale applications to avoid water cooling and its complications and risks.

Not sure? Try this:
Rig up a prop shaft on a board or something, with your motor and prop attached. Stick the prop in a (deep) bucket of water, and run the motor on full intended volts.
If you can comfortably put your hand on the motor after a minute or so, the motor will be fine.

Best if you can also rig in an ammeter, so you can then compare the draw to your ESC's rating... but be careful, as many ESCs have totally unrealistic ratings! But if you're not way overspeeding those 70mm props, you'll likely be in the 10-20A range...
Dec 06, 2009, 11:07 PM
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Time4420- I was watching you thread and saw that you were looking for speed controls for your motors. I would strongly suggest that you stay clear of the Pro Boat speed controls ,(the $40 one that M.A.C.K. Products carries), because of the issues that have arisen about them screwing up lately. We have a new speed control we have tested and are now selling to replace the Pro Boat speed controls which we found to be far more superior.

We are in the process of placing it in our line up on our web site at present, but it is packaged and ready to ship. The unit will handle 16 volts at a 25 real amp continuous load , is forced air cooled with it’s built in blower, and has ultra slow speed control in both forward and reverse. The unit has built in Fault Protection Circuits with indicators, for Over Voltage, Over Current, and Over Heating and are fully automatic with Auto Reset. The unit is 1 5/8”square 2 1/4”high and weighs 3 oz. The Model #7300 sells for $75.00. You can place your order by phone at 732-870-2966 mon - fri, 9am to 5pm.

P.S. This unit is made in the good old U.S.A.
Jan 17, 2010, 03:02 PM
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Almost ready for wax and PVA.
Just fine tuning the keel and finishung the smallest imperfections with surfacing putty.
The hull is down to 220 grit. I'l probably go to 1000grit and then prep for lay up and start by Wed. I'll post entire process a with pic's.
Jan 19, 2010, 11:14 AM
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After 5 yrs, my pro boat speed control failed.
MACK sold my the #7300 for my wood sequin tug.
It is nite and day in performance.
slow to top speed.
With one cabin window open and the smoke stack I have good cooling.
Jan 19, 2010, 11:15 AM
Registered User
IS this Hull your plug for a mold?


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