ready for test...i think

[dreadnought]

Thank you guys for all your help. Here are pics of the 14 v ryobi drill drive with 9 volt makita battery. I will see if it floats tomorrow! the thing sounds like a bucket of bolts. metal gears and the metal gear box rattle pretty good. But everything works. all built from scratch. hull stuff box etc. having a blast.

[LtDoc]

Good luck!
It'll be interesting to hear what happens. If it's not going to be 'floated' in your personal 'test tank' (bath) I think you might think about some ballasting, balance and that sort of thing. Once had a boat that thought it was a submarine...
- 'Doc

[Ghost 2501]

lets see the results dreddy

[arrow5]

Oh yes mucho ballast, that rounded hull form will rock at the slightest provocation. Stay dry and good luck with the test. Put a couple of bilge-keels from lead when ready for that detail. Weight "at each corner is best"

[Rob_P]

Not sure of how far your testing is going but do you have any capacitors on the motor connections ?
I don't see any but maybe its just more tidy than one of mine !

[dreadnought]

Yes lots of ballast. It doesnot fit in the tub (52"). So the test will be at the pond. Bilge keels is a great suggestion. I will have a larger battery as well.

Question..... This motor seems to go faster in reverse. Is getting a prop with the opposite pitch like reversing the motor. I have it on a gear drive so I guess this is why it is "reversed". If so what do I look for. This may be elementary but it is all new to me.

[patmat2350]

Yes, swapping a LH for a RH prop would require changing the motor direction.

Questions:
What's your prop diemeter?
What's the max speed of the original drill? And are you operating on the "stock" voltage?
Does the drill speed approximate the max speed for your prop diameter as listed in any of the prop speed tables at www.raboesch.com (http://www.raboesch.com/) ? (pick 2007 Catalog 2)

All this will help to predict whether the boat will get out of its own way, or whether you get to go back to the drawing board!

Pat

p.s., Did you describe the hull construction anywhere here? I LIKE it! Wide open spaces and all that...

[patmat2350]

OK, I predict a return trip to the drawing board!
Many cordless drills will only do 600rpm or so. Reducing the voltage from the design 14v to 9v will give you about 385 rpm.

A 4 inch prop wants to go TEN TIMES as fast as that, and smaller props want even more.

[dreadnought]

Prop size is 1 1/2. stock voltage was 14.4. I will try 12 volt when I find one. just testing with the 9 volt.

answer to the hull question. It is made wood ship model style. I found some lines on the net. made forms for each station and fashioned a strong back. then steam bent the ribs. attached the sheer plank (fir) then started planking with bass wood from sheer plank to bottom. bottom section is larger sheets. I will put together a little how i did it thing when i get it floating.

answer to prediction of back to drawing board. probably..huh. well thats ok. I only started this project because I had three drills that didnt work. scavenged parts and made two good drills. that left me with a bunch of parts... a dreadnought. the scourge of tingley pond! arrg. :)

[patmat2350]

It may be that the motor WITHOUT gearbox could put you in the ballpark. You'd like to get that 1.5 inch prop as high as 10,000 rpm-- very possible with a bare motor.

If your original drill only does 600 rpm, or even 1200 rpm, it won't matter if you go to 12v with the gearbox there, you'll barely move the water much less the boat.

Upside- with the gearbox gone, you'll be much more stealthy!

[Umi_Ryuzuki]

Regardless of the power package, you have a good looking hull there.
The bugs will be worked out in no time. ;)

[HS93]

If you have a DVM (meter) put it on the motor terminals and check you are getting the same voltage in forward and reverse, you may some speed controlers only give 70% in reverse and its easy to use reverse for forward.

or it may be that the motor has a lot of advance timing, giving it poor reverse but as it is out of a drill it should be neutral

Peter

[johan1212]

Hay this looks cool. Hope the felas here can help you out. I know the workmanship you can do so show us some detail. can you post a profile view? Is your boy showing interest in this? I would like to come down and see it in a few weeks. good luck bro.

[arrow5]

The extra long push-rod for the rudder could be much shorter, maybe just in front of the tiller. Use extension lead (from LHS) but make sure you route it well away from motor. Be sure to add suppression capacitors to motor as the lead will act as an antenna and pick up radio "noise" from the motor. If you do add lead bilge-keels be sure to line the inside of the hull with a thin (1/16th") ply plate to spread the load on your very fine planking. Are you going to post the topside image ?