Mean machines cheap

[ice329]

Quick question and a pic of the mount I made.

On the hardware, does anything go on the tube or does it just slide in and thats it. I have to reset the tube.

[ice329]

Nothing fancy but she is basically roughed in, I got a few little things to iron out but for the most part she is done. She only weighs 3 lbs 6 oz. surprizingly light.

[sewerpit]

looks good, neat and clean. what did you use to get all that crappy bondo off ? the one guy says West System 2 part. dont even know where to get that

[ice329]

I chipped as much as I could, then a hand held dremel with a fine grinding bit and very carefully took it off. I took more off after the pictures. Maybe I can try it out today or tomarrow.

[ice329]

Bathtub test. Auto bailers leak. filled them with silicone. Could not get them out without looking like it may bust the corner of the hull.

[Eodman]

After I got the box and mount out I used a Black & Decker hand held sander with some coase sand paper!

[ice329]

Little help....tuning She runs really nice. I am enjoying this cat. Today I ran it 4 times on just 6 cell Nimh packs. wanted to feel her out before I step it up. First run IB3600 packs and a M445... ECS only 75 (first in cooling line) motor 117, batterys 150+... something not good. swaped the prop, fresh IB3600 packs 1740-3... would not plane. Swaped prop P something the 4 bladed prop, it planed but I didnt care how it ran. Regrouped threw in a fresh set of IB packs and a X642 temps simalar to the M445 ESC 74 Motor 112 packs 150+. Where am I at? Running wet? To much prop? Where am I going with this.... any help. These packs are beasts and they never get this hot. The power plant is a SV system and its running good.

[Fluid]

First run IB3600 packs and a M445... ECS only 75 (first in cooling line) motor 117, batterys 150+... something not good.

That's a lot of prop for that motor unless the cat is set up near perf.

swaped the prop, fresh IB3600 packs 1740-3... would not plane.

The 1700 series are hydro props, not suitable for cats - unless you know what you're doing, and even then there are far better choices.

Swaped prop P something the 4 bladed prop, it planed but I didnt care how it ran.

The P series props are based on the 1700 series, not good for cats or monos.

Where did you get these prop recommendations? They have contributed to permanently damaging your packs. You never start out tuning a boat with large props, always start with props smaller than you think you need....an extra prop or two is a lot cheaper than new batteries.

Regrouped threw in a fresh set of IB packs and a X642 temps simalar to the M445 ESC 74 Motor 112 packs 150+. Where am I at? Running wet? To much prop? Where am I going with this.... any help. These packs are beasts and they never get this hot. The power plant is a SV system and its running good.

Your packs are now questionable and may be over the hill. All it takes is a couple runs heating them to over 150F and they will never be the same again.

Most of your props are too big for the MM (and the wrong designs) unless the boat is trimmed well. At full throttle running straight ahead on fairly flat water it should run on the back 3"-5" of the sponsons. If not then it may be drawing too many amps and needs to be freed up. I assume that the driveline is free without binding, you lube the shaft well, and the power wires are short.

Set the CG at ~8.5" and the bottom of the strut about 1/8" above the sponsons and angled up one degree. See if this helps, but your packs may not be able to pull the model now. Let us know how it goes.


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[ice329]

The props I tryed are just ones I had here. The M445 and X642 are for the SV and the other two I got for the Tunnel so thought I try them, they did not get a very long run. A few seconds at most. The shaft is nice and free. I may try triming it up a little but maybe I need to get a smaller prop. Which are good choices. maybe a X442? I want to run the SV powerplant but on two 7 cell packs

[calcagno45]

ReddyWatts runs the Y537/3 on his MM. I plan on trying this prop on my cat as well. From all indications on the FeCalc, it seems to be an easy going prop with good speed.

[ice329]

OK I am following but I have a silly question. If the SV ESC is a 45 amp unit, it kinda stumps me that even if it was pegged at 45 amps the entire run, the packs should handle that? I would think the esc would get hot. I have a few carbon fiber props that may be on to test a few temps. I will get back on the water and play some more.

[ice329]

I may have found the problem. The strut braket was loose alowing the shaft to go down and flex possably binding the flex but definatly making the strut run negitive. So I reset it, tightened it and will give this a try. Also picke dup a X442 to give that a try also, should be easyer on everything then the X642

[ice329]

OK problem solved. Sort of a combination, part my fault for missing the loose strut. Strut is at its highest position now and somewhat positive, and the boat defiantly does not like 7.2 volt packs. First run with new adjustments, motor 117, ESC 81, 7.2 v batteries 135. Second run same adjustments with two 7 cell ep4500 packs. Motor 129(stock water jacket), ESC 89, batteries 127. all ran with a X642. Much better.

[sdartt]

2 Questions before I Epoxy tonite

1. Should the bottom of the strut, speed master, be 1/8 to 1/4 above the bottom of the sponsons or below the deck?

2. Using a speed master 21 rudder. It looks a little long? If it does need to be
shortened how much should it be below the bottom of the sponsons?

I am building two MM, this is the first it has a fei. XL 10 and esc CC 120. I have gutted the radio box and old M-mount. Installed CF from Darin's supplier.

[DISAR]

Oh I am very happy today. I received my MM. They sent it to Greece for 40$ shipping. Thanks guys for all your information for building this hull and helping find it at low price. I will use:

NEU 1512 2D (2600 kv)
3s or 4s (5000 mah, 20-30C)
Himodel 200A ESC
range of props 40-45? and maybe the V937/3
0.187 flex
speedmaster 21 strut & rudder