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[fastvee]

Hi all!

Just ordered my next hull for my next fast electric build.  -just hoping Mart gets to molding it soon     lol

Now I am trying to figure what stuff to put under the hatch.


I really would like to build this with twin motors but one huge motor is still an option.
Biggest problem is the budget as allways.  -If I would put twins in I would most likely afford just 6s escīs.

For one big motor I could get 200, maybe 300 Amp esc  that is for 10(ish) cell lipos.


I have only seen one build with twin electric power and it was 6s lipos 200A escīs and about 1500kv big can motors.  It went about 60mph.  http://www.youtube.com/watch?v=52Ch_Fdvd8A


Now I allready have one big hull, the navaho and it has 2x 200a escīs and 910kv motors and it goes about 50mph in current trim.

I want this cat to go faster then that but not sure if 60 is enough so I am thinking of getting 1x 10.000wat motor so it should be enough to go 80+ mph easily if I would use 8 to 12s lipos.


If I would build it using just 1 motor it would need stuffing tube under the hull and use skegged strut , never really liked the look of these cause I try to build these to look really scale , had one in my last cat build
( build video here if interested http://www.youtube.com/watch?v=GJrvy-dPUE0 )

What do you guys think I should do here? 

-Pate

[martno1fan]

Hi Pate don't fret im starting her this week coming  ,this Thunderbolt is built by Waverider ME not Tom at Expresscraft just saying    same design but my layup.Its taken me a Cpl of years to get this into production since Tom gave me permission to do it but its paid off as I believe the build quality is very good but I am biased  .
As regards your choices it all comes down to how much you want to spend as allways lol.I think twins would be fantastic,maybe save some Ģ by using the alien twin esc we spoke about like the one I have which is 300 amp but he told me can handle much more,he said it has been pushed to well beyond its limits with no problems .maybe speak with him see what he can offer.
Mart

[fastvee]

Hi Mart, lol you should rename the boat to waverider thunderbolt or something, I just wrote the name that I found from your store 

I am sure that the quality  is perfect as allways. -the navaho has been really solid so far.

 if you have the time let the hull sit in the molds for a week or two lol so it is has straightest sponsons ever  , like you know I am in no hurry to finish this build. that  smiley was just friendly pat on the back

 -just cant wait to see the hull...no hurry...lol

I know you allready know this but for the rest of you reading this:

 -my last cat(32" from horr) had really bad sponsons (the lowets part of the sponsons ride surface was much closer to each other then the tunnel width so the hull was shaped like  \-O-/ )  that thing handled like crap and it has kept me from getting another cat for so long( common problem with cheap cats, too early release from molds makes the sponsons crooked)

Boy was I happy that my fav boat maker started to do this big cat!

And I am def. doing this with twins, just returned from driving the navaho and the twins sounds soo good...

-just need to think if 6-7s would be enough so I can use the cheap escīs  and good motors.(all my cheapo esc failures are caused by bad motors)

Since the us bloke had 6s and 60mph then 70 should be close to truth with 7s... -just dont know if that is enough lol...

Pate

[martno1fan]

No worries mate I leave em in the moulds for a few days while im installing rails etc,as you don't need rails ill need to get on with other things  .
As regards motors im wondering if the higher kv ones would suit on 6 s they do a 1200 kv version of those 5694.Also a 5684 motor in 1200 and 1340kv?.
What about outrunners I know you like those maybe you have some in mind ?.
Mart

[fastvee]

Great! -glad you remembered the rails, I had forgotten to ask you not to install them .glad you know what I want  lol.

The 1717 castles that the us guy used are 1500kv and about 5085 can and rated 120amps,so maybe that
5684 and 1200kv or 1340kv ,just not sure about the amp ratings...-I need to study that...

Oh, outrunners you say... lol I do like them and would like to try the new hk ones but they are not that cheap compared to sss motors.

The 1717 is about 3000watts and this outrunner is 3800watts(x2=10.5hp) ... but the sss ones are even more(or atleast rated more)...

[martno1fan]

Yea I think the sss ratings are a tad exagerated,that said I friend in Australia races using them and side by side versus the leopards he says they run cooler and more power.
If I ever get time  ill be doing a twin Apache with two 5694 motors on 8s,ive just been so busy lately its on the back burner but I suppose I cant complain.Def going to have to be a winter build ready for next spring now.
Looking forward to seeing your build come together,on that note Id best go get the moulds waxed  .
Mart
 

[fastvee]

Hey Mart do you know what amp esc is that friend of yours using and with what motor and how many cells? -and how big boat?

That could help me to calculate how trutful the amp ratings are on the sss line. (or atleast that motor he uses) 

If I can find a motor that is 10-12s capable and under 120A the budget would like it alot...

Really starting to like the specs of this esc , and for that price 2 of them  would be not too big of a problem.

And  remember to take some time off (after my hull is done lol) and finish that build of yours, all work and no play is no good .  -you have to relax also .   

-Pate

[martno1fan]

Hi Pate I think hes using the 40 size and under motors in smaller hulls so not much use to you I suppose.

[martno1fan]

Hi Pate just noticed your other point about cat tunnel widths varying front to back,this is normal.Every cat I have has the same design ie the tunnel is wider at the transom.
The reason for this is to reduce the air pressure created by the tunnel,it allows the air to escape thus reducing lift and tendency to blow over.In other words it helps with stability at high speeds.
The tunnel width on the sprintcat for instance is 20 cm at transom area and 19 cm at front of tunnel floor,on the Thunderbolt shes 22cm at the transom and narrows to 20.5 cm at the front of the tunnel floor area.
Mart

[fastvee]

Hi Mart. good info you wrote thought but that is not what I ment.

Hey, look I found the pic I took years a go  ,that should explain what I am trying to say , I need to learn to write better english lol...  The sponsons on that cat were like this




That is not normal and the cat handled like a crap.

I was told that the reason the sponsons were that way was cause the boat was removed from molds b4 it had 100% cured.

That is why I was so picky about the sponsons on your mold, I trust your work but the plug could have been a bad one,glad it was made of a straight and  fast boat so we know it is good.
Pate

[fastvee]

another one

[martno1fan]

Hi Pate pics not showing  .
Mart

[fastvee]

Hi, i linked the pics from another forum, this time I uploaded them again to postimg, , hope they are visible now.

[martno1fan]

Yea I see them now  .
Mart