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screwball
07-13-2009, 10:28 PM
im getting a micro scat cat soon (thanks jesse) but it doesnt have a strut on it.

so i wanted to know if its safe to run it without a strut for some tests until i get one?

also can someone point me in the direction of an article on how to build running hardware or post up a few pics of their custom made struts.



thanks,
James

Tom M
07-13-2009, 10:45 PM
You can run it, but just make sure the prop shaft isn't sticking too far off the back of the boat. As for custom making them, don't. Its extremely time consuming, expensive and laborous. Just get the one that was listed in the WTB: hull forum last night by Jesse, that would be your best bet.

screwball
07-13-2009, 10:49 PM
ok cool i think i might because i need to pick up some other stuff from steven anyway


thanks tom!

-James

Tom M
07-13-2009, 10:57 PM
No problem James. Me and you are basically in the same boat (I am 15 years old). I am getting ready to build my titan 40 on a budget. Oh, and if you want to convert that boat to brushless, here's the cheapest and best performing way to do it:

Motor- http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=4200&Product_Name=HXT_2835_(380S)_3900kv_Brushless_Inru nner

ESC- http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=7377&Product_Name=Turnigy_Marine_35A_Brushless_Boat_ESC

I know that the esc is a little bit expensive but it's not really that bad. Considering that a brushless conversion for your boat will cost you less then $60 in parts is unbelievable. You definitely got a great deal. That boat will scream with brushless and 3s li-po. I know, I have one that is similar.

screwball
07-13-2009, 11:23 PM
those both look great but i was thinking of using this esc and motor combo

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=270283104971&_trkparms=tab%3DWatching

it seems like a great deal considering its 21 shipped from china lol but i do have a 1/18 sidewinder brushless esc from my rc18t so i may just pick up a feigao 380 and but that in their right now im going to run it brushed and then in the winter ill go bl and lipo who knows lol my b-day is in august so i may set up a cart on hobbycity and go bl and lipo in this little bugger

i just have one question am i going to need a pistix for that esc?

thanks for your quick replies and those links

-James

Tom M
07-13-2009, 11:28 PM
I have ran an aircraft esc in my Proboat Mini C and it worked just fine. Just be aware that the esc/motor combo you chose is an outrunner combo and not an inrunner combo which most people run. And if you already have the esc, just buy the motor from hobbycity for $18 and you have a brushless boat. Thats what I do, I just do an esc swap from my boat to my mini t and vice versa when I want to run it.

screwball
07-13-2009, 11:31 PM
i think thats what i may do



thanks for the info tom

-James

Tom M
07-13-2009, 11:34 PM
No problem James, any time.

screwball
07-13-2009, 11:37 PM
hey do you think i might be able to run this motor http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXLWY9&P=7

or will the torque be too much or will it fry my esc?

it seems like a pretty good deal considering its an ammo

Tom M
07-13-2009, 11:44 PM
I run a 28-45-2100 in my Mini C and its great. Now, I don't know how much room the motor compartment of your boat has, but I think it might be a little bit too big. Your best bet would be to look at the Ammo 28-35-2700 or the 28-35-3900. Those would be your best bet and would not fry your mamba as long as you prop it correctly.

Simon.O.
07-13-2009, 11:47 PM
im getting a micro scat cat soon (thanks jesse) but it doesnt have a strut on it.

so i wanted to know if its safe to run it without a strut for some tests until i get one?

also can someone point me in the direction of an article on how to build running hardware or post up a few pics of their custom made struts.



thanks,
James
How on earth do you plan to run a shaft without a strut.


You can run it, but just make sure the prop shaft isn't sticking too far off the back of the boat
please explain this one a bit more, I am fascinated to see how it is done. :confused2:

As for custom making them, don't. Its extremely time consuming, expensive and laborous
I can make a brass strut with a sleeve bearing using hand tools and a propane torch in about an hour and it costs less than the postage for a bought one.

screwball
07-13-2009, 11:59 PM
tom the reason i was asking about that one is that its a good 30 dollars less that the other one`s lol

i may try my hand at making a strut as i have some materials lying around

Tom M
07-14-2009, 12:00 AM
Well I first ran my Mini V, fresh off a flex cable conversion, with the prop shaft hanging about 1/2" off the back of the boat and it ran fine. You can do it, its just not recommended.

Tom M
07-14-2009, 12:01 AM
James, go for it!! I would love to see how the strut turns out. And my bad on the motor, I thought you wanted something of the ammo brand lol. Seriously though, try that hobby city motor because I will be ordering one for my boat very shortly.

screwball
07-14-2009, 12:20 AM
i just started the strut and it looks petty awsome although im not sure if its going to work but even if it doesnt its still good practice!


pics tommorow

lincpimp
07-14-2009, 12:23 AM
Take a look at these links, you can see the stuffing tube just sicks out the back of the boat. I have the gecko and it works gear. Run a k series carbon 29mm prop, 2s lipo, gh 4700kv motor and a mamba 25 esc. No water cooling, just a finned motor and it runs like a champ, at least 25mph and it will launch out of the water from rest.

http://206.206.85.209/xtdoc/Details.aspx?ProductCode=m-1742/FS&store=mhzusa

http://206.206.85.209/xtdoc/Details.aspx?ProductCode=m-1742/US2&store=mhzusa

The purple gecko shows the al stuffing tube the best.

screwball
07-14-2009, 12:33 AM
since this will be my first lipo im just gonna go with the easy stuff

charger- http://www.hobbycity.com/hobbycity/store/uh_viewItem.asp?idProduct=8247

battery- http://www.hobbycity.com/hobbycity/store/uh_viewItem.asp?idProduct=7309

motor- http://www.hobbycity.com/hobbycity/store/uh_viewItem.asp?idProduct=4194 ( its a couple bucks cheaper )

and some peal and stick foam http://www.hobbycity.com/hobbycity/store/uh_viewItem.asp?idProduct=8999

so assuming my strut works ill have a complete running bl micro scat cat for 85 bucks!!!

-James

screwball
07-14-2009, 12:35 AM
so maybe i wont need the strut hahaha cool

domwilson
07-14-2009, 12:44 AM
I think that is a little bit of a different beast. Those have a solid shaft with a solid tube. No flex there. The solid tube and the bearings support the shaft. Ya really can't do that with a flex shaft and no rear support.

screwball
07-14-2009, 12:50 AM
oh ok well then it looks like strut it is lol

-James

Simon.O.
07-14-2009, 12:50 AM
so maybe i wont need the strut hahaha cool
If you notice the boats mentioned above do not have a strut as they are a vee hull. It is easy to run a stuff tube out the rear of a vee without a strut. I have 3 vees and have tried this on 2 of them .
Your original post mentions a scat cat.
Running a cat with out some sort of strut will be interesting.

lincpimp
07-14-2009, 12:51 AM
I think that is a little bit of a different beast. Those have a solid shaft with a solid tube. No flex there. The solid tube and the bearings support the shaft. Ya really can't do that with a flex shaft and no rear support.

The gecko does use a wire drive, and the actual prop shaft is as long as the tube that sticks out. No bearings, just a bushing. I do agree that it would not work on a larger boat, or a cat. The straight line nature of the al tube is where it gets its strength, plus the boat weighs next to nothing...

domwilson
07-14-2009, 12:54 AM
Running a cat with out some sort of strut will be interesting.

Let it whip!

Jesse J
07-14-2009, 08:26 AM
I'm with Simon AND I made the stuffing tube in the said cat. In this case, the stub does NOT enter the stuffing tube like on the vees, rather it dangles. If you run without a strut your prop will be whipping around like a wet noodle; you WILL damage the flex and could damage your prop and/or hull. Highly NOT recommended.

Make yourself a strut with 1/16" or 1/8" brass plate and a 5/32" K&S tube, will cost less than $5 and require few tools and little manufacturing. You would need a hobby saw and soldering iron. Actually you can use aluminum (if you have access to a band saw) and glue ( JB weld) the 3/16" K&S and slide the 5/32" bushing tube in, see my thread below (here I just glued the 5/32" brass tube directly, no internal bushing):

http://forums.offshoreelectrics.com/showthread.php?t=6561

Do yourself a favor and wait for the strut, you will be glad.

Oh and for motors, I like your ebay option of post 5. I have seen these things fly on the mystery combo that I show in my micro cat post linked above. The only time I ran this thing was when I had a 540S on 2S and it was out of the water more than in... Way over powered. Get used to it with the brushed system and then ease into the brushless, remember its a micro not a monster.

screwball
07-14-2009, 05:58 PM
the jb weld on my strut is dyring as i type this ill have pics of it tommorow

-James

screwball
07-15-2009, 11:48 AM
heres a few pics of the strut

http://i274.photobucket.com/albums/jj269/screwball-13/strut2.jpg

http://i274.photobucket.com/albums/jj269/screwball-13/strut1.jpg


i think it came out pretty good considering its my first try at making one

Tom M
07-15-2009, 11:51 AM
Looks great James. Keep us updated on how it works on your boat when you receive it.

Jesse J
07-15-2009, 11:57 AM
Great, James. That is 99% of the game, take a stab at it and it will probably work! You will have your boat soon and you can work out the details.

screwball
07-15-2009, 12:27 PM
yea im thinking that if i get the boat thrusrday or friday im going to work on it until its ready to hit the water lol

ive already got a few places to run it picked out



thanks again jesse,
James