motor for micro cat

[BoatDoc]

got a new boat...MHZ micro cat. it's 17in by 5in. i'm thinking that my nemesis 8s motor is probably too much. i want a small brushless for this hull, i'm thinking of running 2-3cell lipo's. would a brushless 480 size be good?

[Fluid]

I have the same boat with a 4-cell setup in it. I used a Lehner 480-sized motor, the 1515, and run four GP2200 cells. This works well and with an x430 prop it runs for five laps on the NAMBA oval course, topping out at ca. 25 mph. It will run more if I wanted to. Set up for SAW racing it has hit 33 mph with GP3300s. The little boat is surprisingly stable at any speed!

I think a better sport setup would be a less-costly 480-sized BL motor and a 30-40 amp controller, running on 6 small cells. The GP2000s are AA-sized yet can supply up to 50 amps if needed; they run just fine at half that draw. Choose a motor with around 4000-4400 Kv; on 6v cells it should be fun.

BTW, the current NAMBA 6-cell offshore SAW record was set with the same hull running an Aveox motor....43.77 mph!

[BoatDoc]

excellent! i was figuring on a 480 but needed some confirmation on the idea. the power setups i have considered were: multiplex 480 3d on 2 lipo's or an e-flight 480 on 2 lipo's. the thought had also crossed my mind to put in an 05 motor on 4 cells...but the motor won't fit under the cowl and is a bit on the heavy side. i've got a castle 80 amp ESC so i'm not worried in that department. one last idea was 2 brushless 400's geared together...hmmm. right now i've got it set up with solinger hardware and an expert mini servo for steering. luckily i've got time before the lakes thaw to get it all done. thanks jay.

[BoatDoc]

what esc were you using to run 4 cells???? i've noticed that most brushless esc's start at 6. any pointers for cg? i can't wait to see this little thing go, i know it's going to be a blast.

[Fluid]

The BK electronic controllers usually start at 4 cells; I use an older 7018 model. These are high quality controllers and I use mine in many different BL boats from 4 to 18 cells.

http://www.bk-electronics.com/catalog/index.php?cPath=36_57

Start with the CG 1/4" ahead of the first step (from the transom) and set the bottom of the strut even with the sponson bottoms, angled up 1 degree at the prop end. You may find you need different positions depending on your speed and weight.

Here are some pics of one version:

http://i1.tinypic.com/oh92co.jpg

http://i1.tinypic.com/oh92qd.jpg

http://www.offshoreelectrics.com/micro_iceberg.htm

Or for the scale freak:

http://www.x-ray99.com/gallery/slideshow.php?set_albumName=album12

[BoatDoc]

BK had crossed my mind...i'll check them out. i think i'm going to go with the Lehner 1515, either a 12 or 13 wind with High Amp addition. i'm going to give FDM a call next week and see if he can get me one, along with another hull i want to set up...but that's a subject for another day. if not, i'll go straight to Lehner. thanks for the ideas so far...you can bet i'll be asking more questions before this project is over.

[Fluid]

I had a blast today running the IceBerg again, in SAW setup. Used smaller cells this time, GP2200s and cut over 2 ounces off the weight - about 10%. Made a difference, I'll see what it does at the IMPBA SAWs next weekend. Here's a beauty shot; didn't get a chance to get a running shot, but it scoots.

http://i1.tinypic.com/oj48x5.gif


.

[BoatDoc]

must be nice to run the boats in january. i gave up that perk when i left georgia and came back to WI. do you know an american distributer for BK? or should i just go directly through them to get the esc. i'm looking at the 7020 Warrior. having one of those would really open up some options as far as power setups are concerned.

i just noticed...this is my 1000th post....thus making me an addict!! i hope there's no 12 step that i have to go to now. :D

[Fluid]

Fine Design Marine is the US distributor for BK. Chris does not list the 2070 on his website, but he can usually get about anything BK makes.

http://www.finedesignrc.com/speedcontrolslehner.asp

I've had my 1870 (old version of the 7020) for years and it has been very dependable. :)

.

[BoatDoc]

well, that's great news! chris should be happy the next time i put in an order (as in $$$)...looking at a viper hydro, and motor, plus the motor and esc for the cat, and a bunch of little odds-n-ends. my checking account, however, will not be so happy afterwards, thankfully it's tax season, and i've got quite a return coming this year.

[BoatDoc]

fine design ordered my motor the other day, it'll take about 2 weeks before they get it in, then another week or so before i get it. i had him order the 12 wind high amp. here's a pic of mine as it sits right now.

[Fluid]

They are cool little boats, aren't they? Can't wait to hear how yours runs.... :cool:

[BoatDoc]

i can't wait either, this is going to be a great year. i've got 3 'riggers in the works, my micro cat, i'm ordering an H&M viper and i've got my nitro tunnel. i'll be boiling some water :D :D . I'm also thinking of finding a late summer SAW event to attend and see just what i can put on the water. it'll be my 1st, but i think i should be able to build at least one competetive boat. got a question though...that BK ESC on FDM's site (the 99amp) is that the 9920? if it is that's the one i want because it'll run 4 cells. chris only lists it for 6-20 cells. i have a small 'rigger that i'll be building for 4 cell use and possibly another micro that would be perfect for 4 cells also. i'm getting itchy...we're still dealing with cold temp's and frozen lakes here in the great white north.

[BoatDoc]

i talked to chris the other day, my motor hasn't gotten to him yet (and i'm sure he's sick of me asking...the man should be given sainthood) i went for the 99 amp BK controller. i'll primarily run that in the new 12 cell hydro, but 4 cells in the micro sounds like fun too and that controller will do it. once the motor gets here i should have it on the water lickity-split. can't wait. gotta order up some smaller GP's too.

[BoatDoc]

i thought it would be cool just to show a size comparison to really show how tiny this boat is. this is the MHZ next to my 6 cell rigger.

[BoatDoc]

just got and e-mail from FDM, he had to contact lehner to find out where my motor is. 2 more weeks til he gets it, and then he has to turn around and ship it to me. i hope the smile this boat puts on my face is big enough to make up for all this waiting. batteries are on their way though, 2 sets of GP 2200's from battlepacks.