Fighter cat rocket and New Mean machine single

[Gusmoyer11]

This boat has still not gotten wet! It's been stored on my shelf waiting on weather and r/c crawler projects to end.. I got my other boat on the water and now some local guys have sparked an interest in the boats. So the funds are getting pumped into this project. They all seem to be going the spartan or genesis route.

First question:
Can I run 4s on a sv27 speed control? It's 45amp hooked into a 1500kv out runner. It handles 3s just fine. This is in a bling rocket running 30.9 on the garman. Just seams like it has more to give. Super stable!!

#2
Here is the build thread. On the main topic,

mark-s-mean-machine-t1272.html

For those that don't click the link, it has a castle 1515 2200kv.
220 swordfish esc. 5.5 batt connectors 6.5 motor connectors.

I'm new to the boating seen so any and all help would be great.

The motor mount has four mounting holes, but the bottom one is a super pain to get to. Is it really needed, or can I just loc tite the others?

I was told to try a m445 so I ordered one from a member already balanced and ready to go.

Also I ordered a set of giant power 4s 5000mah 65c packs.

If anyone has any experience with this hull please let me know. I'll be tuning it next week. Not club racing just local guys with Spartans around. Many ideas on what kind of speeds to expect?

Thanks Gus
In Coos Bay Or.

[Gusmoyer11]

Any ideas on where I will need to trim this rudder up to?

[NativePaul]

1, you sure can, most folk run SV27s on 4s and 1500kv is suitable for 4-6s, the amp draw will go up a lot though if you use hthe same prop you are using on 3s, so like with any new setup start with a small prop, check for heat and work up if there is room to.

2, 3 motor mounting screws will be fine, many mounts only have provision for 2 and work OK, thread locking any bolts without locknuts is a good idea.

3, I run a 135mm rudder on mine, but it has a little more chord than yours so you will probably want a little longer, it has to be at least a few mm below the water pick up if you want to use it. Unfortunately the only way to get the right length rudder is to cut it down a little at a time until you get handling problems, then buy another and cut it to the last length that handled OK.

[tlandauer]

Any ideas on where I will need to trim this rudder up to?

Beautifully built MM.
The MM needs a relatively long rudder in order for her not to spin out, I will run her like this first, then if you really want to shorten it, no more than half inch. I have mine at that length since the shorter Speed Master rudder (http://www.offshoreelectrics.com/pro...d=ros-spdr-005) would not do the job. Switched to the longer version (http://www.offshoreelectrics.com/pro...d=ros-spdr-001) and the MM turns on a dime going full steam. What I have not done is shorten it, as said, you will have to trim it until you get problem and buy another one, I was not in the mood for doing that. But I remember I was told half inch off mine would probably be fine.

[properchopper]

Here's the rudder length for this MM : (it's in a customer's possession so the picture is all I have ; should give a fair appraisal 'tho)

DSC05343.JPG DSC05407-1.JPG

It seems to corner OK

https://www.youtube.com/watch?v=m2rt6sH8jwE

I use a highly scientific method to determine just where to cut/trim called the "inter-ocular trauma test":

I just stare at the full length rudder and when the correct spot to cut hits me between the eyes, I grab the cutoff wheel.

[Gusmoyer11]

Thanks for the great info guys. It's nice to see proven setups. I'm still in the process of finding more props to test with, I have no idea what prop is on the bling rocket. I got it from Keith Bradley, over a year ago.(the entire boat) but it seams to run cool at 3s so I will bump it up once the battery's arrive.

Can I run a 3 blade prop On these boats? More then anything I like the looks. What are your thoughts on the cnc aluminum props?

Proper chopper, what wheel is on your customers boat?

Do any of you guys know what speeds I could expect out of each rig?

[Gusmoyer11]

image.jpgimage.jpgJudging by the shape an dia the prop on the rocket is likely a x440 dia is 1.57/8

[NativePaul]

Take the prop nut off, and the size will be cast into the back of the hub where the nut was.

Personally I run Octura, but CNC props are pretty popular here and typically lave a little less load for the diameter than a M shape Octura, Tenshock props are the best of the bunch and run really well. Having modded a few Tenshock CNC props for friends that run them, I will say that the alloy they are made from is probably 7075 T6, it feels a hell of a lot harder than the 6061 typically used for hardware, and at least as hard as Octuras stock BeCu mix (I haven't got into hardening BeCu props yet), 7075 is known to be hard to bend and crack easily, but I have not had any issues putting some tweaks into them. Personally I would want to do a little work on any CNC prop I have seen before I ran it, as they are none I have seen were knife sharp or perfectly balanced but they just wanted a tickle on the edges to get right, and I know many people that race them stock from the pack, I have borrowed a couple of stock ones and while the balancer said they were out, they are so close to balance and light weight that I tried them my boat made no funny noises and exhibited no noticeable extra prop walk. My verdict is that they are good enough from the factory, and can be made very good with minimal work, if I was starting from fresh without a big box full of Octuras I would probably running them on most of my boats. If you want the ultimate in strength for high power handling they are hardened as much as can be whereas you can harden a BeCu prop further or stainless is harder stock, and can be hardened further.

[Gusmoyer11]

So I got the mean machine on the water today, not very impressed. It did 29.9 on gps. I played with battery loc. it runs best with them all the way back. The packs are 4s running in 2p. 5k mah each. I tried my m440 it would not plane at all. So I put a 42x58 traxxas plastic spartan prop it got up and went.....Slow.

[tlandauer]

Boat should run at least in the 40's if not higher with the 2200kv CC 1500 motor on 4s2p. Have you calibrated your throttle curve to max.?
Judging by the picture, most of us have the strut set higher than you, bottom of strut between 1/4 to 3/16 above the table surface. With 1* of negative trim, neutral will be fine too.

[Gusmoyer11]

I'm not sure how to set the curve. How do I calibrate it?

As for the trim, it runs flat that's why I put the weight in the rear.

I did not set this boat up. So I'm learning as I go. How does the trim adjust? Just simply loosen the bolt and move it?

[Gusmoyer11]

IMG_0439.MOV.mov

[tlandauer]

First of all, do you have the correct COG? 30% from the rear transom to begin with.
Maybe you need to dial in some positive angle instead of the negative angle I suggested in the previous post.. In any case, IMO your strut is too low, loosen the bolt and pull up, set the boat on a table top, then measure the gap between the table top and the bottom of the strut.
I have my phone and can't tell what ESC you are using. You need to re program /calibrate the throttle. Set throttle end point adj. On your tx to MAX if you have that feature on your tx. I just think something is not quite right when you have that set up and it's doing hardly 30mph.


Sent from my D6708 using Tapatalk

[tlandauer]

IMG_0439.MOV.mov

Link doesn't work....

[Gusmoyer11]

I just went thru the calibrate process, I'm guessing I got it right. I have the 220a 6s no lights that I can see though. This thing makes all kinds of beeps when going thru the steps. I will work on the strut after I mess with the settings on the controller. I'm running blind on the settings, I don't have the link or a box yet. Going to order them next week.