Cat Build(Here kitty kitty kitty)

[Eodman]

Good morning folks nice to be here!

Need some help would like to build a cat over the winter, I want to hang 2 Graupner outboards(the 650s) off the transom. Will stay with NiMh for now, would anyone have an opinion on the length of Cat I should look for? Maybe even what brands to consider?

My son & I use Spektrum transmitters on our Supervee & Traxxas!( waiting for the Blackjack Brushless) So that will stay the same!

I'm guessing that if I use an electric hull that I should add some glass to the inside of the transom to reinforce but I'm not sure!

At this point this is just fun for us, we don't race!

Any help would be most appreciated!

[SJFE]

Hi & welcome. Nice to see another cat guy. I would suggest a Scat Cat 26, BlackJack 26 hull or a H&M super cat-s. FYI The Graupner units are only suited for brushed motors. You will have to replace them for brushless. I for one have been wanting to do a build like this for a long time. I can't wait to see yours :).

[Eodman]

I typed NiCD while my brain was thinking NiMH ! So please just plug NiMH into my first post!

[Steven Vaccaro]

Changed NiCd to Nimh for ya. If I was building a cat I would consider the ep1 outboards. They will handle more power than the graupner one.

[Eodman]

The only reason I was considering the Graupners were that they appeared to be a little more powerful! But I am new to this game so if the Aquacraft EP1's are a better choice I"ll go with them! Guess I better change my wish list!

[SJFE]

I agree with Steven on this one. The ep1 will stand up to more power but is a little more work to maintain due to it's bearings & gears. Well worth it though. If you choose one of the glass hulls reinforcment is not an issue with the exception of the transom. Now with an abs hull you will need to some reinforcment. Keep in mind the weight you have hanging off the stern and plan your battery placment for the proper center of gravity. When it comes to an esc I would reccomend a set of rc hydros or a novak evx.

[Eodman]

Well alright -- We have the outboards resolved(EP1'S) -- the servo & receiver will be from Specktrum -- the esc - hadn't gotten that far! Now the hull -- will a 26' be long enough or should I look for a slighly longer one? I'm not looking for 100 mph but don't want to end up with another boat like our Villian! Don't get me wrong I love the Villian but its a little slow!

[Eodman]

Anybody else out there have an opinion on the ESC? Remember I'm new to this!

[SJFE]

You have to be carfull about the size of the hull. You want it to be light and not much over 26". Keep in mind you will only be able to run a minimum of 19 to 20 turn brushed motors. Anything lower will burn up.

[kck741]

What about Fullers Outboards

http://www.drcwebservices.com/ffe/images/cfoutboard.jpg

You can get it ready for just about any motor you want Brushed or brushless

[Eodman]

Steven - What hulls under 30" do you offer! When I look at alot of the cat hulls It would appear that the motors will have to be mounted way out on the sides!( becuse of the tunnels) But I'm not sure! I think the Kitty will perform better and handle better if the 2 out boards are closer together!

An alternative would be a bracket hung off the transom to mount both EP1's to, but much harder to make look nice!

I haven't ordered the EP1's yet so I'm not sure of the size of the mounting plate of each or the size of the transom area over the tunnel!

Any input would be appreciated!

[Eodman]

Hey SJ where do you live in NJ I'm right by the bridges on Parkway!

I looked at the Novak EVX ... I'm guessing it's the Traxxas Marine EVX you were refering to! That"s nice - easier to wire & water cooling is easy!

I think the Traxxas part # is 3015 although some sites say it is discontinued and replaced, not sure of the new #!

Now I 'm pretty sure the esc is identified ... Now I've just got to find the right hull!

Help me Somebody ...Pleaaase Help Me!

[Fluid]

The BBY ScatCat 26 (really only 24" long) is far too small for two outboards and its transom is impossible to use OB on without major reworking. You should consider the ScatCat 32 or similar size hulls with a flat transom. The Mean Machine may work well because it is wide with a flat transom, but it is heavy.

You should mount the OBs close together in the tunnel, not out at the sponsons. To get the CG correct (about 32% forward of the transom) you will need to put the cells 'way forward to balance those heavy motors hanging outside the boat. Good luck and be sure to post pictures!


.

[mr.mauian]

my MM is 4 lbs. 14.8 oz. without batts. I guess if I run someone over other than a MM they gonna sink...hehe.

[skidooguymxz550]

i say mount them on the sponsons. look at all the real outboard race cats and tell me what you see.

[Eodman]

SJFE is the Traxxas esc the same one you referred to as the Novak EVX? Would you know the new part#????

[Darin Jordan]

Hmmmm... I wonder if somethink like this would work??

http://cgi.ebay.com/Brand-New-30-inc...QQcmdZViewItem


The price is about right...

You'd have to get rid of that rudder mount in the back... Or maybe use it to mount an dual outboard mount to... That'd put the outboards QUITE a ways back, however... Not sure if that's good or bad... A lot of the real thing have them hanging out there on extensions like that...

[Eodman]

Ok the hull(MM) & motors are ordered(EP1's)

Heres what we got:

Hull Mean Machine
Motor Aquacraft EP1's
Esc Traxxas Marine EVX2 Steve & I spent 3/4 of a day emailing one another trying to ID this new esc! Thanks Steve
Reciever Spektrum
Servo Spektrum

Now it's just wait until everything comes in. Could someone point me to a good trustworthy graphics company stateside. I'm an old fan of Jaguar Racing and want to do the graphics like Group 44 did their Cats! Green strips on white body with a leaping cat on either side of cockpit! I'd be willing to send the hull to them to get it right but just want to know I'll get it back and in one piece!

[Eodman]

Well my first package came today!

The Mean machine & EP1's arrived now the fun can begin. I have some sanding & filling to do on the hull and cover!

Will post pictures soon but in the mean time here's a few pictures of my inspiration for my graphics!

[Eodman]

Well here's the 1st pictures of the EP1's hung on the 29" Mean machine!

I have reworked the cover because of the wire locations & will post pictures later today(I hope).

Tried the float test and batteries will need to be pretty far forward or maybe some lead to offset weight!

Still don't have all the hardware -- waiting on the Traxxas Marine EVX from someone! Until I get all that at least set in the boat I really can't tell about balance!

Can anyone see a reason my steering servo can't be forwardly located! Will the length of the servo rods greatly effect the steering response?

[Eyekandyboats]

cool
why are the so close together,
each lower unit should be directly behind the sponson.

[Eodman]

Apparently, there are 2 schools of thought on outboard placement:

1 school is mounted close together, the other is out on each sponson!

Now this is my first build and not for racing so I elected to go close together!

When I was young(late 50's early 60's)we had a summer home on a lake in Sullivan County NY & there were actually 2 cats on the lake that had dual Mercury's on the backends and they were close together..... so drawingn early life input I elected to go close together!

If it doesn't work I can always change it!

[Darin Jordan]

Well here's the 1st pictures of the EP1's hung on the 29" Mean machine!

Hmmmm... That looks good! I may have to rethink my hull choice!

Can anyone see a reason my steering servo can't be forwardly located! Will the length of the servo rods greatly effect the steering response?

Shouldn't be an issue at all... OPC tunnels have LONG steering rods for their setups...

[Eyekandyboats]

Yeah my steering rods on my n2-opc are 10 inches long . hehe! but because its a push pull it wont matter low long they are.

[Eodman]

That what I thought about being push/pull just wasn't sure!

I've added a few more pictures of the cover mods I've done! As you can see in the one picture I've cut part of the rear edge away & added an interior wall! When the motors are mounted the wires interfere with smooth steering so to give it more room I added an inch & 1/8th under cover!

As i go along my thinking is to cut holes in the top edge of the transom and pass the power leads thru soft tubing & add a little silicone to make a good seal!

I stole proboat's idea to keep the front of the cover locked in place, now I need to find a neat looking thumb screw (2) for the rear of the cover!

I'm just trying to come up with ideas for the servo in the last picture while waiting for the esc!

Also I need an antennea mount (small) for the edge of the hull -- I don't want to go thru the cover so it 's got to be small in diameter!

The more of the electronics I can locate up forward the less weight I may have to add!

[Eodman]

Steven confirmed that he shipped the ESC out to me today .... now I've just need to wait for it & the Geko(gps) to come in & start working on placement of everything!

Has any one tried that two part flotation mix thats out there? As it expands does it expand too much and create bulges ... or.... would I be better of using the Great Stuff in the blue can! Apparently it is a more controlled expansion!

[Darin Jordan]

I'm of the opinion that you are going to want a servo and push/pull setup for EACH motor... I don't think a single servo is going to hold up well, or give you recise enough steering... Push/Pull means that a single motor has a rod pushing, and a rod pulling... so one rod is always in tension and the other in compression...

The way you have it here, I think your steering rods are going to take a lot of stress and also think that steering will be sloppy...

I'd go with two servos and a pair of steering rods for each motor... ESPECIALLY if you are using standard sized servos (under 50oz torque...)...

[Eodman]

Thanks for the advise Darin, I certainly have the room for two!

My problem is not knowing the specs on the servo's. They are Spektrums and I've been looking for the spec's must not be looking in the right spots! When I upgraded to the Spektrums(2) controllers each one came with the following servo's --- 1 Z270 and 1 Z570(I think thats the number)! The first is their standard race servo and the second is their high performance racing servo! If I remember right the 570 has a brass spline coming out the top while the 270 has nylon/plastic out the top! I'm not sure the 570's are home!

If you think I'd be better off with 2 so be it! Now whats the best way to wire them to the receiver?

[Darin Jordan]

If you think I'd be better off with 2 so be it!

I think you'd be MUCH better off with two... Otherwise, your outboards will flop around a lot... Those 270s and 570s sound like what came in my ProBoat Miss Bud... A pair of the 270s or ??? would be fine I would think... Not ideal, but adequate... for all our racing, it's been recommended for the OPC tunnels to not use anything less than 100oz/in torque... but my AquaCraft ProFisherman worked fine with the 270 in it... (push-pull, of course...)

Now whats the best way to wire them to the receiver?

That's EASY!:
http://www2.towerhobbies.com/cgi-bin...4&I=LXWB69&P=K

[Eyekandyboats]

two standard servos should be just great for that!.
I love the room in the MM hull.