Thunder Tiger Bandit 3.5

[Jaco Engelbrecht]

Hey all, need help with my Bandit 3.5 O/B (Stock standard). The other day I was running the boat, full throttle up & down (just broken in) and it ran very good except for the next moment when it dive into the water full speed for about 2 seconds and jumped out like a bullet. This was on the 3rd tank for the day, the water were very smooth with no wind (Ideal weather). What is the problem? My CG is between 29-30% and if I must bring it down to 27% I must add +- 100grams of weight on the back side. Do some okes add weight to the back and that much and if so, where? I dont want my boat weighing a ton. Or must I lift/drop or tilt the motor.

 

[CapeTown73]

Hi Jaco,

Send me a PM ( I'm on here as 'CapeTown73' ), and let me have your e-mail address. I also run 3.5 tunnels (at our club in Cape Town), maybe I can offer some helpful suggestions with your Bandit.

Cheers,

Wennie.

 

[Jaco Engelbrecht]

I have seen a few topics of the CG and balancing issues on the tunnels, but now im confused. Some okes say 27-30% and the other 30-32% for a starting point. Who is correct?

 

[camaroboy383]

Hey all, need help with my Bandit 3.5 O/B (Stock standard). The other day I was running the boat, full throttle up & down (just broken in) and it ran very good except for the next moment when it dive into the water full speed for about 2 seconds and jumped out like a bullet. This was on the 3rd tank for the day, the water were very smooth with no wind (Ideal weather). What is the problem? My CG is between 29-30% and if I must bring it down to 27% I must add +- 100grams of weight on the back side. Do some okes add weight to the back and that much and if so, where? I dont want my boat weighing a ton. Or must I lift/drop or tilt the motor.

jaco, im assuming you are running a tt o/b on that bandit???? i would start with your trim angle first, tiny bit at a time, like a degree.. another thing that can be going on is to much lift from the prop. when the engine starts pulling good rpm the prop could be lifting the transom too much and planting the nose which cause the nasty hook/ plunge to the bottom..check your engine depth on a very flat surface,( set up board) .. where does the center line of the prop shaft end up???? what prop you slingin??? if engine adjustments and props dont fix the problem then maybe id consider the change to the cg but your pretty much there with the 29-30 % ... another thing is im not familiar with the bandit (never owned one) possibly a set of stumble pads added to the tunnel could create enough lift on the front to solve the problem???????? thats if it doesnt have them already.. had a ts2 that hooked and plunged constantly the pads helped alot..those tt's will run with some help also so remember if you want to go faster you dont always have to pay a arm and a leg... tim duggan and jerry wyss are the tt guru's around here,they really know how to make them sing.. B)

let us know how your making out... also welcome to the board..

alden

 

[camaroboy383]

I have seen a few topics of the CG and balancing issues on the tunnels, but now im confused. Some okes say 27-30% and the other 30-32% for a starting point. Who is correct?

as you can see they are all agreeing on one thing and that is 30%,, great starting point..

alden

 

[Jaco Engelbrecht]

Okay so my balancing point or cg seems right, will try the trim angle next. I have installed the pads underneath the boat but did not try it out yet - raining here and the wind is a bit rough, but hopefully soon.

As I can read, the best fix is patience and small changes - I will eventualy get there.

But thanks, will let you know over the weekend if the weather plays along.

O yes, ja its the original .21 tt motor that came with the boat, with stock prop - dont ask me what prop it is, its got 2 blades that r realy sharp . How do you okes know what prop is what, I dont c any writing on mine. Im still dumber than dumb with the boats - 10years in electric and nitro cars and trucks, but 2 months in the boating game and so far it seems enjoyable except for my boat thinking its a submarine when on full speed.

 

[camaroboy383]

Okay so my balancing point or cg seems right, will try the trim angle next. I have installed the pads underneath the boat but did not try it out yet - raining here and the wind is a bit rough, but hopefully soon.As I can read, the best fix is patience and small changes - I will eventualy get there.

But thanks, will let you know over the weekend if the weather plays along.

O yes, ja its the original .21 tt motor that came with the boat, with stock prop - dont ask me what prop it is, its got 2 blades that r realy sharp . How do you okes know what prop is what, I dont c any writing on mine. Im still dumber than dumb with the boats - 10years in electric and nitro cars and trucks, but 2 months in the boating game and so far it seems enjoyable except for my boat thinking its a submarine when on full speed.

:lol: :lol: :lol: numbers and letters are on the hub part of the prop,,right under the nut that hold it on.... if its the last run of tt's it has the prather 215 on it,,older tt's came with a prather 220.. pull the nut off and see what it says im curious???.. is it a stainless steal prop??? if it is for sure a prather 215 or 220.. copper berylium could be anything... let me know..

alden

 

[TCHedOff]

Okay so my balancing point or cg seems right, will try the trim angle next. I have installed the pads underneath the boat but did not try it out yet - raining here and the wind is a bit rough, but hopefully soon.As I can read, the best fix is patience and small changes - I will eventualy get there.

But thanks, will let you know over the weekend if the weather plays along.

O yes, ja its the original .21 tt motor that came with the boat, with stock prop - dont ask me what prop it is, its got 2 blades that r realy sharp . How do you okes know what prop is what, I dont c any writing on mine. Im still dumber than dumb with the boats - 10years in electric and nitro cars and trucks, but 2 months in the boating game and so far it seems enjoyable except for my boat thinking its a submarine when on full speed.

Jaco,

Take the prop off an look at the back of the hub of the prop - should be some #'s there that identify the prop.... then you can look it up on a prop chart.

 

[camaroboy383]

little somthin to tempt you..... :lol: :lol: ..... this is what your tt can look like with a little elbow grease,,,, right jerry... we got another tt guy on the board.. pretty soon youll be able to quit plumbin and start moddin for a livin.. :lol: :lol: :lol: pretty soon we will be fightin over parts... :lol:

 

[Jaco Engelbrecht]

Hey thats my motor....but not my kezoz pipe, I want that kezoz pipe.

Im currently at work, gonna take the bandit for a spin tomorrow - wil check that prop and let you guys now.

 

[camaroboy383]

that pipe in the pic is a mark hopper htb silver bullet hp.. you can look mark up on here or his website htbboats.com.. very nice guy...

but if i told you that you could just slap a pipe on that thing id be lyin to ya.... the port timings in the tts from the factory are way to low to have the pipe even do anything for you... the port timing must be raised to accomplish the need for a pipe as well as a nicely made head button..j.w makes killer head buttons for these things..crank intake window timing will be changed as well..

but you could put that thing on a slight diet if you wanted to,,, its not much but the skeg on the bottom of the lower can be cut back intern shedding a little weight.. the factory skegs are monsterous,, i think you could turn a 60" hull with that thing..this pic is a lower jerry did for me when i first became a member here and was lost.. i just cleaned it up and polished it when i got it back.. pay attention to the skeg,as thats the whole reason im posting the pic....

see how far it got cut back..still turns like it has tons of skeg too....

alden

 

[Jaco Engelbrecht]

Yes ive seen some major mods on the boating sites. Never realised that the rc boating is so big. My modding days will come, I just want to get use to everything. I have read that the tt bandit is not a great tunnel so Im just gonna play around with it to get some experience then Im gonna get myself a big scary monster. And this is the perfect place to get help and ask around.

Thanks for the pics - that bottom end have some elbow grease on it.

 

[Jaco Engelbrecht]

Okay I have removed the prop and its a prather 215. Any other suggestions?

 

[Jerry Wyss]

TT's like the Octura X637 and the X640,, They are really fun cut-out for a pipe, even in stock form.

Then you can do things like "cutting the water down going thru the head" and taking the .010"

stock head shim out. The pipe wont really do anything but act like a better muffler but it helps

alot in accelleration to a higher speed.

Cutting the skeg (rudder, fin) will not be totally necessary until you mod them to a much higher level.

The faster you go, the less rudder you'll need.

Basic cut-out example,

 

[camaroboy383]

TT's like the Octura X637 and the X640,, They are really fun cut-out for a pipe, even in stock form.Then you can do things like "cutting the water down going thru the head" and taking the .010"

stock head shim out. The pipe wont really do anything but act like a better muffler but it helps

alot in accelleration to a higher speed.

Cutting the skeg (rudder, fin) will not be totally necessary until you mod them to a much higher level.

The faster you go, the less rudder you'll need.

Basic cut-out example,

For sure jaco, snag your self a nice x637 you will like it.

I was wondering when u would pop in jerry.

This is the guy to listen to jaco.

Alden

 

[Jaco Engelbrecht]

Just called our local hobby shop, they dont even know octura props, so I will go to the city and get myself the x440/m440/x637 to play around with.

Is it difficult to use a prop balancer? And what is a nice rough water boat, sometimes the water is not good for the tunnel (A Vee or something).

 

[Jerry Wyss]

Just called our local hobby shop, they dont even know octura props, so I will go to the city and get myself the x440/m440/x637 to play around with.Is it difficult to use a prop balancer? And what is a nice rough water boat, sometimes the water is not good for the tunnel (A Vee or something).

That is the big problem with 3.5 tunnels, or any small boat on rough water. I suppose in the cheaper price

range the TS2 would be a choice thats available,, I think they're still available :unsure:

They're a longer boat than most the other tunnels but a larger boat will steal some speed from a stock TT.

I live by a fairly large lake,, its a lake where full size APBA boats come to set records in this country. But

being a large body of water the wave action would normally make it un-usable for models.

I had to search out a smaller body of water and found it on private property belonging to a farmer that

went to school with both my parents,, How Lucky is that! I ran on it for 4 years before he asked "what's

your last name?", It's been all good since.

My first prop balancer was a two single edge razor blades bonded to a wood block with a 3/16ths inch

piece of steel rod,, Very scarey device with kids around,, and even some big kids like me.

I use a "modified" Top Flite Power Point magnetic and use the Prather (i think) shaft with the thumb

screws. I have a Preston Hall "jeweled" balancer but I rarely use it over the magnetic unit.

JW

 

[camaroboy383]

Just called our local hobby shop, they dont even know octura props, so I will go to the city and get myself the x440/m440/x637 to play around with.Is it difficult to use a prop balancer? And what is a nice rough water boat, sometimes the water is not good for the tunnel (A Vee or something).

you can get the props you want around here if you cant find them... bob cormier sells raw octura props.... mark sholund, props 4 u,,,sells props also... he is a prop artist,,does very nice work..

thier are tons of balancers out there, some very expensive,,and some not so expensive.. i have a dubro balancer that works really well,, but i always liked magnetic better.. was a guy on ebay selling a balancer called zero g or somthin like that... very nice balancer,many have them on this site..only down fall is the rods bend fairly easy supposidly.. also they are quite expensive...

i too used the razor blade home made balancer for years,, works great but like jerry said kinda dangerous,, after a couple sliced fingers you will find your self looking for a more user friendly one...lol :lol:

have you ever sharpened and balanced a prop???? if not be sure to get some info on how to, before you start,, doesnt take much to ruin a good prop..

alden

 

[camaroboy383]

Just called our local hobby shop, they dont even know octura props, so I will go to the city and get myself the x440/m440/x637 to play around with.Is it difficult to use a prop balancer? And what is a nice rough water boat, sometimes the water is not good for the tunnel (A Vee or something).

i would have to say either a v hull or a cat for rough water,, although there are some tunnels that perform pretty well in rough water.. for instance the htb 290,, but i think its a little heavy for the stock tt... my 290 runs just fine in about 1" to 1 1/2" chop,, more than that and forget it..

had a ts2, not sure i would recommend that hull,, i had nothin but issues with mine,, i think they just dont like the weight of the tt... quite the eye opener when i switched to the htb hull..

but for sure the best rough water boats ive ever owned is v's...just my experience..

alden

 

[Jerry Wyss]

Careful with Sholund, its nothing bad about Mark, its just that the TT propshaft is not quite 3/16ths.

Mark cleans up the propshaft bore to fit his jig and some can wobble on the TT shaft. Theres a way

to fix this but its easier to just learn to do the props yourself if you can. An X637 doesn't take much

work, mostly taking off flash and balancing. The 637 and the 640 are the only props you'll ever need

on a TT geared lower unit. I run several 21 powerheads on the TT lower and they all like the above

props over anything else,, it makes life much easier in the prop department.

JW