Thanks Dave & Gregg,
Feels like I'm now going forward with this project. Will consider both motors Graupner 600/700 & "550" motor defiantly a bigger ESC.
Will let you know progress. thanks again John

Westbourne sell a semI decent "550" motor, which may suit you needs. its a low current motor, using way less than the graupner spec, but the esc still needs uprating from the meagre 20amp you have at the moment, running it at 17amps will definately get it hot!

I use a pair of these 550 motors in a Graupner Salina sports boat, complete with water cooling coils and it give a good speed and lasts at least 30 mins on a single battery pack, usually a 11.1v 5000mahr lipo. with 3 blade "antI cavitation" props 35mm.

HI John
Thanks for the additional info. I have just looked up the motor Speed500 Race E 7.2v (7306) on the Graupner web site. The specs are quite specific that this motor has a permissable motor direction R. I assume this means the shaft has to rotate in one direction only as other motors in the Graupner range are L or R. I don't know exactly which direction of rotation is correct for your motor and I assume you have set it to run according to the prop fitted. if you check with an ammeter you may find that the motor draws more than the quoted 2.5 amps at idle in one direction. if this is your normal forward it is also possible that the Max current is higher which may explain the blown fuses. I had two Graupner Speed 600 on my Trent Lifeboat and found them very power hungry and prone to overheating so swapped them for 2 brushless. I was advised to switch to Graupner 700 so if you are considering a bigger motor this may be the way to go. I would have used these but they were too heavy for my Model Slipway Trent.
Hope this helps.

A bit more information:
Battery connected in parallel
Prop - Brass 3 bladed aprox dia 35/37mm

Motor - Graupner Speed 500 E (Nr.7306)
Nominal 7.2volts
Operating voltage range 3.6 ... 8.4 V
No-load speed 22500 min-1
Idle current drain approx 2.5 A
Current drain at max. efficiency 17A
Blocking current drain approx 85 A
Max. efficiency approx 70 %

Prop shaft nicely aligned & runs freely (No binding)
Planning to use water pump on a separate battery.

Thanks for info, looks like the motor I'm using might not be up to spec??

HI Seasick John
Nice looking model. Setup seems not bad for starters but you have not given details of your prop. if you were blowing 15-20 amp fuses this suggests a large coarse pitch (possibly 2 blade) racing prop OR you were sailing in a lake with lots of weed which was fouling the prop. Two 7.2 batteries? Were they connected in series or parallel? I am assuming that your motor and prop were in alignment and that there was no binding on the propshaft. A quick look on line reveals 500E specification:
Nominal voltage 12 V
Operating voltage range 6 ... 12 V
No-load rpm 12000 min-1
No-load current drain 0,4 A
Current drain at max. efficiency 2 A
Current drain when stalled 10 A
Max. efficiency without gearbox 67 %
Max. efficiency without gearbox 66 %
If this motor was drawing 15-20 amps for any length of time it would be very hot. I can't quite see the motor markings on the model so assume you have given the correct model number.
I suspect a too big prop or binding drive shaft, if you have not used lock nuts the connections can and do tighten up on the water.
I would stick with your present set up for now. When you get that working correctly you will be in a much better position to look at other options, such as brushless.
Hope this helps but please ask if you need more information. 😀

The power handling output of the motor controller should always aim to be a minimum of twice current rating of the motor, or near to the "stall current" of the motor used.
I would suggest that a 20 amp controller is way short of the mark and a 50amp is only just on the "cope level".
Id try not to use the water pump too much if it is linked "power wise" to your drive batteries, as the water pump will use a few amps to run.

The motor itself may only take a running current of 1 or 2 amps when checked, but its when you hit the throttle and demand full speed that the motor "stall" ampere figure comes in to question.
At least you have fitted a fuse link in your boat [WELL DONE} , many boat builder seem to neglect such a safety item, till its too late and either ruined a battery or an expensive esc controller.

My up date on refurbishment:
Having read above, I now relies my motor / ESC set up is totally crap and after test on the local pond, found out the hard way (Continuously popping 15/20 amp fuses)
My set up:
My Transmitter / Rec 2.4 GHz Planet
Motor - Graupner Speed 500 E
ESC - Montroniks 20amp
Batteries - NI-MH 7.2 3700mAh (x2)
Also note fitting a 6v/12v water pump for working fire 'squirtey' hydrants.

So which forward,
Go brushless (Totally new to me!!) or more conventional set up replace ESC & motor to more suitable set up?

Was thinking of trying a 50 amp ESC with my existing set up...?
Any advice welcome?

Guys,

I'll use my 12FG then

so 12 channels what to use them all on 😁 😁 😁 😁

actually I'll be using my 6 channel receiver but 12s always an option 😁 😁

I have the fast modual in one of my 9c's no problem with range in a boat

Peter

Dave,

I know with a plane I can hit 1km out easily 😀 😀

I have a 6 channel receiver I can use so I'll try that and see how it goes 😊

now the power system....

marklinks
What a super set. Read the review and no mention of restricted range. Should prove great for a model boat in sight from the shore. Just make sure your receiver aerial(s) is always above the waterline.

found this power system on the bay

http://www.ebay.co.uk/itm/320952488549?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649#ht_1622wt_1141

Hi,
yea I know 35mhz is a no no for surface models

my Transmitter has a 2.4ghz module Futaba Fasst system

this is it:

http://www.flyingsites.co.uk/reviews/fg12.htm

not sure if I'll have surface range though

Marklinks
If its 35Mhz you can't use on a surface craft. The Module is a 2.4Ghz that replaces the 35Mhz module in the back of the T8UP Futaba. Dual rates is to see off fellow club members if they decide to have a race - basically it allows the setup to be much more hairy! - not very friendly to sail but sorts the men from the boys 😀

I use two futaba 9cs and the newer or last of the 9c and have never flown one uses the JetI system 2.4 with feedback and the other uses the futaba 2.4 modual , plus several smaller futaba 6ch sets all 2.4 and a few of my old JR 40mhz sets converted to 2.4 but never needed the extra bits to set up brushless controlers.

peter

HI Peter
My model is the 34" version and very light weight. I originally ran without any help from the transmitter but was basically just using the trim otherwise the model was out of the water. OK dual rates is to allow me to see-off some other fast boats when the mood takes me plus it helps with the turns at speed. EPA works but exponential means I can tune the model to my personal preferences and ability - increasing years mean my reflexes are not what they used to be. I am not really a speed merchant and like to see my models sail realistically from start to full speed. 😀

End points if for servo full movement control to make it more or less, often more to sort out ESCs

Dual Rates is to set up so you can either have full movement or say 50% and my 12FG radio allows each model to have around 12 subsets of D/R per model per channel as well same applies to End points as well

but Dual rates on a boat makes no sense you'd do it all on end points ?

Dave,

tar for the heads up

my radio will never have a need to be modded if I use my 12FG radio it's 12 channel set and has more options than I have dinners in a month! not sure if to use my current radio as its meant for air models not surface so unsure if to use it...

Dave M WHY do you need (exponential and end point adjustment together with dual rate) we never have I have run several different types of brushless speed controlers and set up plenty in boats for people all you may need is end stop agustments.


peter

a single drive with a thumper from overlander (when they get them back in stock) will go well also as I poste on Mayhem twin motors make the go very well the first run was recorded at 22MPH without a sinle tweek or swop of props on cheap Giant cod motors. so they go well , Ill find the model number of the thumper.

peter

Tried to reply to your new thread but there is a problem so am replying here.
If you are going brushless you may wish to check that your chosen radio gear has exponential and end point adjustment together with dual rate. FrSky do a combo conversion for existing R/c gear - I converted a 35Mhz T8UP with a plugin (CT8F) module plus 8 channel receiver for about £27 from GiantShark. 😀

Nice boat, that looks way quick 😊

I do have an issue its set up for a single drive system and I do want to re-do the set up on the drive set up.

Now it looks like if I follow your set up I'd not be far wrong...

HI Marklinks
I use an 11.1v 2000mA LiPo in my 34" Firebaot. EZRun 60A SL ESC and RC Smart 3480 brushless with a direct drive to a 35mm 3 blade brass prop. All up weight is 1900gms.

Sorry if I was teaching you to suck eggs - didn't know you were another flyer. I am attaching photo's of my setup to help with your build. This shows a different motor and battery but the details are the same with the above setup. My advice still stands but look for 48" setups.

I use a Futaba 6Ex transmitter as I had to adjust the ESC using the end point and exponential throw functions as well as dual rates otherwise the model was trying to take-off.

With the larger model you may want to fit two props as per the original, plus two rudders. With brushless you should be able to use scale brass props. The racing type props will overload the motor and from my experience and observation of other models offer no benefit.

Dave,

its the 48 inch model, there no drive system prop shaft or anything

happy enough to use li-pos I fly RC planes so li-pos are no stranger to me
have all the balancing kit here and charger.

unfortunately my DiY skills leave a lot to be desired so she will only get a basic tarting up BUT she will sail and will be water proofed!

HI Marklincs
Looks like the 34" version. is there a prop shaft installed? When you say 6v, are you considering a SLA battery? For the smaller (34") version of this model NiMh of 7.2v and high amp are usually used. Really need a nice fast revving brushed motor to get the model on the plane and you will need a high amp (possibly water cooled) ESC. if cost is not a factor then you could install a brushless motor and ESC powered by LiPo battery. There are certain Important procedures to follow if using LiPo's and a special charger/balancer must be used. For a novice user a brushed motor set up is probably the best option.
As this is a relatively small boat it is most Important that you keep the weight as light as possible. The original kits were sold to work with an IC engine and weight was not a factor, but is when you use battery power.
I suggest you have a look in the power set up section on this site for 34" Fireboats as there are many combinations that work well. 👍 I also suggest looking in the boat build blogs as many rescued hulls need some repair and sealing to make watertight. 👍 if an IC was used in your model the prop shaft, if present, will possibly have damaged bearings and maybe shaft. This can be repaired or replaced but is best done before you start any other restoration. 😀
Please keep asking the questions as you progress. Restoration can be quite daunting but there are many members on the site who can and will gladly help with their own experiences and methods.
Good restoring.

Hi
I have just picked up one of these off ebay that I'd like to get up and running but it has no running gear.

So what ESC/motor/prop do you guys recommend and thinking 6v power system ?

Brian,
Currently doing a similar project as your self.
Gifted a very old crash tender first built in 1956...
As can be seen in very poor state with all fittings missing. Boat size is 34" (1/16 scale), so will be looking for a full set of fitting in the near future.
Started stripping down boat, plus waiting for some plans from e-bay.
Will keep posting progress like your self, hope we can help each other as we progress.
Question: what size is you boat?

got some more done this weekend