Simons Bigger Cat.

[Ub Hauled]

Niiice SImon! Let's see what she can do! maybe even lift the strut a bit if she does not unwind...

[andym]

Simon good to see you finally see the light on prop size, will have some props done soon that would rip on that pussy. Are you running counter rotating ??

[Simon.O.]

I got on the water again this morning with the big cat.
After last weeks runs I made a few changes.
I moved the packs to the front again to set the Cg at 31%
I reset the struts to 0deg and 6.5mm centre above sponson bottom.

2 passes went well but not spectacular, so I tried a quick alteration by reconnecting the motors for outward rotation. NOT good. She was all over the place and very keen to flip at speed.
Back to inward rotation and lower the struts a bit. Very nice

The last few passes were with the struts up again at 6.5mm centre and about 1deg positive.
With a gentle breeze this seems to be a safe setting.

The packs were low by the time I had this setup so I will have to wait until next week to try a few more things.

I can safely say that I am now in the low 50 area for this one. Given that my big rigger is good for just shy of 70 and this Cat looks to be up that way. That is a very conservative guess. I hate to over rate my hulls based on the eye speedometer.

Todays tests showed me a few things.
Inwards is better than outwards for this hull.
A lower strut is aggressive and may be usable, higher is safer !!
A bit of AoA is good for this hull.

No video untill that Crab on a stick gets up here to film it for me.

[norbique]

what motor(s) are you using Simon?

[Simon.O.]

what motor(s) are you using Simon?

Norbert, I have a pair of these.

http://www.hobbycity.com/hobbycity/store/uh_viewItem.asp?idProduct=11181

Power is 5S by 3S+2S 4.5Ah Turnigy 30C packs.
All fed by a pair of Sky-wing 120A esc's I got off e-bay

[norbique]

nice one! What ESCs are you powering those with?

[Simon.O.]

nice one! What ESCs are you powering those with?

These

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=400144150767&ssPageName=STRK:MEWNX:IT

[Simon.O.]

New plan !!

Now that one of the 1600kv motors is coming out and going to a new home, I need to make room for the new motor(s) .....well ya can't just pull one out of a twin now can ya
I was never real keen on the lack of room anyway so now is a good excuse to make a bit more room to accept the longer motors.

While I was doing a bit of cut and paste on this hull, more cutting really, it crossed my mind to do a sealed area for the motors like I have with my Mid size rigger and go with air cooling on these OR motors. I may just do that anyway later.
The thing I love about these OR Heli motors is they can get quite hot and not demag themselves like a lot of IR motors.

Anyway here are some pics form this afternoons cut and paste session, yes while I was doing a c+p on the Big rigger too, multi-tasking there.

A lot of sanding and sealing to go but the idea is in place and I'll get it sorted before the "Typhoon" arrives

[Simon.O.]

My theory for repower follows , if you get bored easily then click the backspace button.

It currently has a pair of 1600kv 500size Heli OR motors in there, they get hot but not worringly so as I am told OR's can get quite hot and not demag like IR cans do.
They are fed with 100A E-bay escs that are not water cooled and these get well warm but again not worryingly hot. Fed from a 3S+2S 4500 30C-40C pack split to to the two speedies.
This gives me 135-160A max from the batts
Therefore 67-80A per ESC and motor motor.
The motors are suggested max W of 1500 which on 5S is 81A.
All of these upper figs are the suggested burst ratings.

Given the packs are not overly warm or anything like hot or swollen I suspect I am down near the 30C area of their operation.

Therefore I figure I am looking at 60-70Amps available per esc and motor.
Yes the Typhoons are suggested at 55A but that is a gamble I am willing to take as they are not to expensive.

The reason for all of this is I have a Typhoon 1800 that is too hot for the Mid rigger and I need one of the 1600Kv motors from the cat for that rigger.
I either buy another 1600kv motor and leave the Typhoon on the shelf or buy another Typhoon and have a 1600kv spare for the rigger and get the Cat going a bit quicker too.

As you can see I sometimes calculate myself to near insanity but this is what I love doing.

Enough of my waffle for now !

[norbique]

looking forward for more...

[Simon.O.]

All sealed and ready to wet sand down and varnish......again.
There are so many layers of different varnish on this hull and so many mods that I now have a real "wooden camo" colour scheme happening.

Just a couple of pics from today, I can get a tape seal down on the hatch to deck, so it is good to varnish.

[graill]

Looking good. What paint/colorscheme you going with Simon?

[Ub Hauled]

I love it mate! I think she has lots of personality

[Simon.O.]

Looking good. What paint/colorscheme you going with Simon?

The pretty standard colour I always use, varnish and lots of it !!

I have considered painting hulls but I then remember I suck at painting and have little patience for it plus the fact that using good electrical tape to seal hatches has a tendancy to pull paint off, back to me sucking at paint prep etc.

I'll keep the good old rough look I have, when the clear(ish) shiate pulls off and exposes wood I just sand it back and go again.

I'll sweat the finish when I get a hand laid hull from Hans

[Simon.O.]

Props ??

It currently spins 445's with the 1600kv OR motors from 5S and is a very nice hull to run.
I do know I can get more out of it as I have done the good old fashioned idea of "wind it up 'till it blows over and then back it up a notch" Towing in an inverted cat gets old real fast.
There was a noticeable difference when I went from 440 to 445 props, fair to say the strut had to move up to make all this happen.

Now that I am about to hit it with a few more rpm 1800-1900 up from the 1600, I intend to run 440's to trial it with sweet sounding revs.
My initial thought is to keep the struts as is and see if they actually bite and see how it all goes, another side of me says that it is known/seen that raising the 445's gets more speed.
It is all now a massive quandry in my mind.
Run them deep and load it all up for initial runs and then lift them and let them spin out as I like.
I did like the 445 over the 440 for the 1600 kv motor.......it looks like I have to start the whole thing over again.

This is fun and is why I keep doing it all........new Rigger, near new Canard.....ah so much R&D to do all again.