LDM

My Feedback: (15)

Any suggestions on a power system , I want to go electric but this is a very big boat .

Tachikaze

This boat is not so big that you can not go with an electronic power system. We are running longer boats in combat R/C with twin electric motors.
Unless you want this boat to stand up out of the water when you hit the throttle, you do not need to gear reduce the motors. Gearing the motors will suck up more battery power so that you can use a more powerfull motor.
I would look at a pair of something like the All Electronics surplus DC motor catologe number DCM-165. See the link to the site. [link]http://www.allelectronics.com[/link]
This is very similar to what I am using to run an Italian destroyer that is 57" long and weighs in at just under 17lbs.

LDM

My Feedback: (15)

THANKS THAT IS GREAT INFO !!!

pompebled

Hi LDM,

Looking at the type of boat the Donzi is, I'm not shure if you want it to perform like a scale warship.

If you want the boat to come up on the plane, you'll need something bigger.

I'm thinking of two direct drive 700-Series motors, maybe even 800, and run them on 16 -24 cells a motor, depending on the type motor you select.

Another alternative is using two ventilator motors, used in cars (the ones that cool the radiator), see if you can find two identical ones at the local scrapyard. (possibly for nothing...)
These motors run very smoothly and will speed up your Donzi very nice, take the 12V motors, and run them on 18V.

Greetings, Jan.

LDM

My Feedback: (15)

yes , after visiting the site I realized the motors are way to small, i m anot looking to race the boat butit must come up on plane , thanks for the advice . Somebody told me about a site called Harbor models in Nothern Cal ? I was told they have all ypes of motors for this boat

pompebled

I still say: scrapyard....

Lots of power for very (if any) little money

The pic shows my fan motor to the left, a 60mm short can 700 motor, and a 540 motor as comparison.

The fan motor has can cooling and brush cooling, weight of the steel can has been reduced by sawing out large openings.

Greetings, Jan.

LDM

My Feedback: (15)

oK jAN i AM GOING TO GIVE IT A SHOT

subsinker

My Feedback: (61)

I built one a couple of years back and used a set of Astroflight 25's I was very pleased with the results. The boat had scale speed, planed very nicely and at 25 lbs made quite a wake. Very realistic. In addition, with the Astroflight motors you got a sound that sounded very much like twin diesels running. Just make sure you cool them somehow as in the hull of that boat there is very little ventilation. Good luck with whatever method you decide to go with. It is a very impressive boat and looks great on the water.

LDM

My Feedback: (15)

Thanks , also a good idea. I ahve been a plane builder so this is all new to me but its nice to put work into something thay is less likely to crash .What betteries did you use

sierrafoxtrot

Hi,


I started on a Donzi Z-65 about three years ago, almost finished it before I had to put it on the side until now. I have the radio and the speed control on the way(the only thing it lacks). I am glad to hear a review on the Astroflight 25s'. That is what I am using in direct drive. Twin Asflt25s'. I am ready to get it in the water. It will have a turning open array radar, which will add a sparkle to it. Not to mention genuine marine bottom paint that is tarnishing on the sides for a realistic look. I agree that it is a nice boat. Its size makes should make a realistic wake too. It looks awesome floating in my pond. I will get some pics of it on th go when I get the stuff installed.


Greg

Al Stein

Thanks for the fan motor idea, Jan.

Any ideas how much current they draw at or near 12V? What do you use for a speed controller?
(My personal project is a 1/144 Atlanta class (light) cruiser)

pompebled

Hi Al,

Just tested it: no load, 1,3Ah

Slowing it down with a cloth and a pair of pliers I reached 5-6 Ah, burning my fingers when accidently touching the shaft (hot!)

On 12V it revs about 3000-3500 RPM and turns a 65X (race) prop without any trouble.

The one in my MTB runs on 20 cells and has can and brush cooling, it still has to get hot....
I know guys that run these 12V motors on 36V, but they take the trouble of rewireing the anchor with thicker wire, less turns (more rpm) closing the gaps in the anchor to prevent the wiring from coming out as a result of the centrifugal force, with cardboard strips and epoxy resin and balancing the anchor again. I haven't felt the need to go that far, yet...

The runtime on my MTB is about 20-25 minutes, depending on how long I run it full throttle, that gives me about 10 Ah drain.

I think, that in your cruiser, a moderate size speedcontroller will do, as you will probably not want it to run as fast as my planing (1:20) MTB, especially not in 1:144 scale.

Greetings, Jan.

Al Stein

Thanks for the info -- that sounds great!

You've got the part about running speed right, too. Scale-like behavior for this boat is pretty low speed. If I can run it on a few amps or so and I don't have to worry about maximum efficiency or maximum power throughput, I think I can put together a very inexpensive electronic controller... especially since I can use water cooling or other heavy technologies that are kind of impractical in airplane models.

Ooh, come to think of it, I used to have a spare fan control from my Vega... when it comes to cost, there's nothin' like free -- if I could just figure out where I would have put it!

subsinker

My Feedback: (61)

I have found that a flight box battery works pretty well. The boat is large enough to hold it and the extra weight that the battery has helps get it down to the waterline. I use the 12 volt 7AH battery. They run about $20.00 and will power the boat for quite a long time. Also, I do use a separate battery for the receiver. Better to be safe then sorry.

Al Stein

This is hopefully not an issue for the Donzi, but for some of us who will intentionally expose our boats to a fairly high probability of sinking, are there "wet cells" suitable for that?

I gather that "sealed" cells aren't really sealed, so if that's the case, they'd be out. And I have no idea whether a gel cell battery would also be messed up by being submerged or not.

Anybody?

pompebled

Hi Al,

The sealed gel lead batteries can be used in any position, even upside down if it needs to, so it's safe to asume that they are truly sealed.
Should the battery get punctured during a crash, you'll probably lose the whole boat, because the force required to spring a leak in your battery will certainly damage your hull...

Regards, Jan.

Al Stein

Cool -- thanks.

I'm not too worried about crashes or physical damage to the batteries -- I figured that something that extreme is going to ruin a hull and maybe a radio, too. I'm happy as long as pond water won't seep in and dilute the "stuff" in the battery if my surface combatant goes under.

SHEP.

do any of you have any pics of this boat built ? i am looking for all kinds of angles to get a better look at it because what you get is not that great and i can't find any good ones on the net

i have looked all over the net and can't find anything[:@], even on the Dumas website they have only one pic and it's not even that great

i have a fellow that is starting to build one for me because i don't have the time or the room to do this size of a project

i have 2x .40k&b's for it to make it more scale


also you know any good sites with custom rc boat stuff on ?


thanks

LDM

My Feedback: (15)

Here is what I did , however I did not start to built the boat yet so I do not have pictures .
1) I called Donzi in Florida , asked them to send me a pamplet on the boat for a prospective client who was interested in a boat .
In-tern they sent me a fantastic packet on this boat with tremodous pictures inside and out . For the record there are a ton of changes to this boat from the original version it was modled after .

2) A good source of boat supplies is Harbor Models in San Franfransico

SHEP.

anybody have any pics or no where i can find any ?

and i have looked on the Dumas site and i can only find one and it's not that great






thanks

LtDoc

SHEP,
I don't have any pictures but most of the R/C supply places carry them, 'Hobby Lobby', 'Tower', etc. I get mine from 'Hobby Lobby', but that's just habit...
- 'Doc

PS - Go here; http://www.modelboatmayhem.co.uk/
Martin has a very good 'basic' tutorial on electric stuff, motors, batteries, etc.

Haoleman

My Feedback: (3)

Hi Guys,

I just broke down and bought a Dumas Donzi kit from Hobby Barn. Should arrive in a few days. Have a question to add to all the above. What about running hardware minus the motors. Is it better to get Dumas hardware kit or does someone else have better gear? I plan to use this boat on our pond here for the new sport of RC Sportfishing! Should be a lot of fun if the alligators don't get too curious. Also, please post your results on the choice of motors and how they worked. Would like more info on the Astroflight motors(which ones).
Thanx,
Terry

Haoleman

My Feedback: (3)

Another question. Is the deck on the full scale made of teak? If so, what is a good source of scale wood to duplicate it?

Thanks,
Terry

LDM

My Feedback: (15)

Terry , I think the deck is teak . You can go to a Micheles craft store and get planks of wood used for doll house , there is all types. Then either use a stain from Home Depo or Michales for exact look .
The donzi boat is made in Floirda so you shoudl be able to get some great refferance locally .
AS far as supplier in the US , the best source I have found is Harbor Models in SanFrancisco .They are experts on Electric big boats and set up .

Haoleman

My Feedback: (3)

Thanks for the sources! My wife suggested Michael's too. Didn't realize they had stripwood. I will check next time we go down there.

Terry