Setup help

[bjornar]

Hi, I have been asked to build a 120cm Riva Mahogany boat. The thing is that it weights 13kg. Its actually in Mahogany. What kind of setup can be used for this heavy hull?

[Jesse J]

What speeds do you want, how much do you want to spend, what batteries you want to use? Are you starting from scratch on the hardware/electronics? any limitations? Got any pics of transom and motor bay?

It would be really cool with twin inboard/outboards... Let me spend $1000s of your money to set it up and you will love it...

[sailr]

You're not going to see great speeds from that hull so I would go with 'realistic'. You need one of the big Astro brushed motors and their speed control or one of the big old Pittman motors if you can find it.

[crabstick]

plett bm370 LOL

[sailr]

http://cgi.ebay.com/Astro-Flight-Cobalt-40-w-Superbox-Electric-Motor-NEW_W0QQitemZ170347475551QQcmdZViewItemQQptZRadio_Control_Parts_Accessories?hash=item27a980325f&_trksid=p3286.c0.m14&_trkparms=65%3A1%7C66%3A2%7C39%3A1%7C240%3A1318%7C301%3A1%7C293%3A1%7C294%3A50

Not sure what the final output rpm would be. You could contact Astro Flight.

[bjornar]

What speeds do you want, how much do you want to spend, what batteries you want to use? Are you starting from scratch on the hardware/electronics? any limitations? Got any pics of transom and motor bay?

It would be really cool with twin inboard/outboards... Let me spend $1000s of your money to set it up and you will love it...

I am going to build it/them for a guy thats going to sell them RTR. Its going to be a Zenoah version aswell, and I need this to go at least as good as this one. It looks like I will have 10000 NOK (1400USD) to get this rtr. And the point with this is to get it as close to the original as possible.

[sailr]

Another approach is to use a NEU 2215/1Y motor, Castle Hydra 240 and 6S2p 5000 lipoly battery setup. Problem with this is that the cost of this power system alone will eat up your budget and you haven't built the boat yet!

[Jesse J]

how about twin Speed 700s with the Jetti 60 ESCs on 4S2P each? Hobby City has 4S lipos for $52.

so $300 for motors/esc, $200 for batts - and still $900 to burn.

The economical route - given that these are to be RTRs.

[bjornar]

Another approach is to use a NEU 2215/1Y motor, Castle Hydra 240 and 6S2p 5000 lipoly battery setup. Problem with this is that the cost of this power system alone will eat up your budget and you haven't built the boat yet!

Yes, this will be an expensive setup. But also a very good one. But I think the original have underwater prop, and this setup will give over 30 000rpm. This will take very much amps?

[bjornar]

how about twin Speed 700s with the Jetti 60 ESCs on 4S2P each? Hobby City has 4S lipos for $52.

so $300 for motors/esc, $200 for batts - and still $900 to burn.

The economical route - given that these are to be RTRs.

This sounds good, but I would like just one prop because this is the original.. Can this work with just one engine, and where can I find it?

[Jesse J]

You still may want the power of two motors - just gear them to one drive line. For this size you might want to go .25 flex as you will be putting lots of torque on the poor shaft. Or if you are not interested in performance, you could go straight drive line and not have to worry about breaking it.

You can find the motors here on OFE: http://www.offshoreelectrics.com/pro...prod=ose-700sc
and ESC: http://www.offshoreelectrics.com/pro...prod=hl-je600n

What hardware were you thinking?

[bjornar]

You still may want the power of two motors - just gear them to one drive line. For this size you might want to go .25 flex as you will be putting lots of torque on the poor shaft. Or if you are not interested in performance, you could go straight drive line and not have to worry about breaking it.

You can find the motors here on OFE: http://www.offshoreelectrics.com/pro...prod=ose-700sc
and ESC: http://www.offshoreelectrics.com/pro...prod=hl-je600n

What hardware were you thinking?

I was actually thinking straight drive. Thats the closest to the original.

[Jesse J]

So this is going to be a classic inboard with a rudder that is below the transom?
Are you still wanting to go single motor?

[sailr]

The idea of two motors into one gear box and a single straight shaft is actually probably the best suggestion yet.

This is a hughey drive for example:

http://www.rcgroups.com/forums/attachment.php?attachmentid=183748

You still may want the power of two motors - just gear them to one drive line. For this size you might want to go .25 flex as you will be putting lots of torque on the poor shaft. Or if you are not interested in performance, you could go straight drive line and not have to worry about breaking it.

You can find the motors here on OFE: http://www.offshoreelectrics.com/pro...prod=ose-700sc
and ESC: http://www.offshoreelectrics.com/pro...prod=hl-je600n

What hardware were you thinking?

[Jesse J]

Thanks Jim - that's the exact kinda set up I had in mind.

I don't know how much it would cost, but I am sure going with two brushed motors/escs you ought to have room in your budget.

Should be a pretty sweet set up!