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[v8moneypit]

New to the forum. 2nd timer for RC boats in that I used to run a few in my teens and early 20's. I'm... err... 'a little older' now!


Having always wanted to build a Huntsman back then, when I saw they were still making the kits, I had to buy one! So I am now just about finished building a GRP hull 34" version. I'm running a 700 motor through a 25A ESC off a 12v lead acid battery. It's not the highest standard of build, but I've enjoyed it and looking forward to it's first outing very soon 


I am also about to start converting one of my old boats from a 1.5cc to electric. This is a smaller and lighter animal, so I'll probably use a 400, but I'll be back to ask advice on this nearer the time.


Anyone on here from Norfolk?


Steve

[Martin (Admin)]

Hello and Welcome to the Mayhem Steve!

NB: Free Mayhem lunch every 32nd of the month.

Please post a photo of your Huntsman!
http://www.modelboatmayhem.co.uk/forum/index.php/topic,23.msg403457/topicseen.html#msg403457

[v8moneypit]

Thanks for sorting out the registration Martin. Never did receive the e-mails!


I'll get a few pics sorted and posted.

[v8moneypit]

Here are a couple of quick snaps of the Hunstman.

[Seaspray]

Welcome aboard Steve. Nice boat 

[v8moneypit]

Well, she got wet for the first time yesterday!


Given she's hauling a lead acid battery, she isn't exactly fast, but the 'weight' in the water gives it an element of realism. Can't get anywhere near up on plane though.


Handles really well. It was rather choppy and very windy, but she coped really well.


Had the tiniest dribble of water inside. Think it's coming through the rudder mounting hole. A bit more gloop needed!


After half an hours running, mostly flat out, the motor and ESC were both only luke warm. Bonus! I've got car brake pipe coiled round the motor. I know it's not the best heat transfer, but it seems to take something away.


Anyway, thought I'd update you on the progress


Rgds
Steve

[Seaspray]

You could try battery packs instead of the lead acid. and make up the ballast with lead here an there if needed. If water is coming up the inside of the rudder shaft a little grease will help. I've seen me put an O ring just under the servo arm then push it down against the O ring. Got a picture of inside the model. Motor cooling, I use Robbe condensing coils part no. 1451 never had any trouble with these.

[v8moneypit]

I think the water is actually coming through the rudder mounting hole rather than up the tube. Hence the 'gloop' comment!


I had thought about trying battery packs to get the weight down. I like the long running time from the lead acid, but it might be interesting to see what difference the lighter batteries makes. What voltage would you recommend I try?


There is acres of space in there, so I can have a choice of where the put the batteries. I built in a couple of compartments at the bow in case I needed ballast up front.

[Tug-Kenny RIP]

I would go for a larger motor.

It looks like you have the room inside.  Failing this you may like to try a brushless motor which might get it up on the plane.


Cheers

Ken

[v8moneypit]

Thanks guys.


I think I'll run it as it is for a while, but might try the different batteries as an experiment. Then, maybe a different motor. Would the step up to a 900 make a huge difference?


I have zero experience of brushless motors. I see a specific ESC is required and some shops offer a bundle. But what power brushless equates to brushed Graupner sizes? And I believe they rev higher? So would the existing 40mm prop be OK?


Sorry for all the questions!

[Seaspray]

You could consider going brushless.. seems the way everybody is going now

 If your going to stay with the 700 best contact The Component Shop  as I don't run big motors like the 700

[Perkasaman2]

You mention a 40mm prop. Is it an 'S' or an 'X'  rated item? The 'X' version will give a significantly higher performance. Which model of Graupner 700 motor are you using? If you are using a BB rated 700 size motor then a larger 45X prop can be used and your Huntsman will go a lot quicker.

[v8moneypit]

That's really interesting. I'll check on that.

[Tug-Kenny RIP]

I see you've mentioned mine and Stavros's favourite engine. The 900.

It might be worth mentioning here that the size of the motor can's diameter is suggested in the name.

ie...... the higher the number, the bigger the diameter.  Not sure if it relates to millimeters but, no doubt, someone will put us right here.

Cheers

Ken