Kbb 34" mono build

[kfxguy]

Good stuff guys. I'm all for the ideas and willing to try them. At the moment my plan of attack is to get some longer and maybe a tad wider trim tabs. I just haven't found the ones I want yet.

[kfxguy]

There is a point of too much speed, but he hasn't quite reached it..................if anything he needs more stability than I have on mine..........I'm hittin 67, not 30 FYI.

What are the rules.......enlighten me please.

I will say this, on 6s which has been 69.xx a few times, it's smooth and stable...but when I pass the 70 mark it starts acting funny so something is going on

[flraptor07]

There is a point of too much speed, but he hasn't quite reached it..................if anything he needs more stability than I have on mine..........I'm hittin 67, not 30 FYI.

What are the rules.......enlighten me please.

I'm not going to get into a big argument with you but you're wrong about the trim tabs. For instance if you move the tabs out like you say to do, what exactly are they doing when the hull is aired out?

[keithbradley]

Btw, on 6s with the smaller prop it only went 64mph. Put the m447 I did last night on and it went 65. Wonder if longer trim tabs will help with the chine walk? That's why it flipped. I tried to stay in it and it flipped and hit hard. Landed right side up tho.

That's WAAAYYY better. it's probably running a lot looser with the smaller prop, hence the chine walk. Did you try moving the tabs down a little?

My math says it should go 66mph with a x447 on 6s...you went 64mph.
Same math says 77mph with a x648 on 6s...you went 69mph.

The first one is by far a more efficient setup and will likely get you the same 75-76mph on 7s, with a MUCH lower current draw.

It would be worth it to try a 3 blade prop too. I don't recall what all they make in normal rotation. If it was a twin setup the logical choice would be x450/3, but you have more options since you're not limited to counter-rotating sizes.

[Make-a-Wake]

I'm not going to get into a big argument with you but you're wrong about the trim tabs. For instance if you move the tabs out like you say to do, what exactly are they doing when the hull is aired out?

No your not, cuz I'm not gonna.............I'm wrong hmmmmmm? I guess I should just quit the forum since you can surely handle all the thread questions with the exact answers. I've seen some of your boats run on Bills RCG threads, not hugely impressed. You have had your share of mishaps and setup problems. You wanna go there? Ask Bill if I know how to set up a boat, curious to hear his answer.

I simply know how to set up fast monos and am giving Travis some pointers while all you are doing is criticizing others posts...........whatever dude.

BTW, my tabs are double wides, start inward and extend much farther out.......I simply have wider tabs.

[tazman]

I've been reading up on chine walking. Not much info on rc boats. Little bits here and there. Do I've been reading up on 1:1 boats and what they do. Here's some highlights:

1) happens easier in calm water (water was like glass today)
2) longer trim tabs help
3) sometimes more blades on the prop helps
4) angle of trim tabs help
5) slack in steering is one major factor, the main reason a lot of boats do it
6) raising the prop usually helps. In my case it really didn't.


So there's a few ideas for me. I'll get it lined out eventually.

That is dead on travis. My 33' checkmate has twin650's and will start to chine walk on glass smooth water and the only way to stop it is a little bit of down tab. Chop does not do it at all. Boat runs 103 in chop and 98 on glass. Chine walk is when the boat rides high on the vee and starts to rock back and forth to try and find the water again that is why is is worse in single engines because of the torque of the motor . With your boat being a single alittle down tab or a little kickout on the rudder would help the torque roll to the right causing the boat to walk. Longer tabs are a big help. They touch the water sooner with less angle to a short one.

[Spartanator]

As far as I know, he is the only guy running this hull so he has to play with it.

Everyone has hiccups, some bigger than others. Not going to take sides since I have never shook anyone's hand here.

I personally think that the trim tabs should only be close together if purely for speed runs as they could be used as a ride pad. If they are used for slightly choppy water I believe they should be outwards.

[flraptor07]

No your not, cuz I'm not gonna.............I'm wrong hmmmmmm? I guess I should just quit the forum since you can surely handle all the thread questions with the exact answers. I've seen some of your boats run on Bills RCG threads, not hugely impressed. You have had your share of mishaps and setup problems. You wanna go there? Ask Bill if I know how to set up a boat, curious to hear his answer.

I simply know how to set up fast monos and am giving Travis some pointers while all you are doing is criticizing others posts...........whatever dude.

BTW, my tabs are double wides, start inward and extend much farther out.......I simply have wider tabs.

All you did was attack my builds, you didn't answer the question. I never claimed to be a expert and I deffinetly have my share of set up issues. You never said anything about wider tabs you just told travis to move his out, for that you're wrong! ON THE TABS I'm just stating what I know to be fact, when the hull is aired out the tabs on the outside from about the center of the transom out do almost nothing. I'm not criticizing other posts just one part of yours, the only thing I said you're wrong about is the tabs nothing more..

[tazman]

As far as I know, he is the only guy running this hull so he has to play with it.

Everyone has hiccups, some bigger than others. Not going to take sides since I have never shook anyone's hand here.

I personally think that the trim tabs should only be close together if purely for speed runs as they could be used as a ride pad. If they are used for slightly choppy water I believe they should be outwards.

Agreed. The closer they are to the vee the more you lift the boat. A little bit out and just touching the water would at as a stabilizer without a lot ot lift and I am just going by what I have seen on the big powerboats. It always doesn't scale down to our hobby because of the speeds. This would be about 700mph boat at full scale! Lol

[Luck as a Constant]

Some interesting theories in here....


Sent from my iPhone using Tapatalk

[Spartanator]

Some interesting theories in here....


Sent from my iPhone using Tapatalk

Wait til' we get to your thread..... haha

Sorry Travis for doing this to your thread. Hope them Mud Bugs were good today! That lil' guy looked a bit ANGRY!

[kfxguy]

It's cool, I don't want you guys to argue. I'm sitting here thinking how the best way for me to test what's better, in or out. I hate to drill a bunch of holes in the hull but it looks like that's the only way I'll find out. I can easily fill them once I'm done. I guess this will definitely lay this question to rest. I just ordered some longer tabs so hopefully they will come in within the next few days.

[Luck as a Constant]

I think longer tabs will be a good start. Although the ones you have could work, they seem a bit small for that hull. I used the same ones on a df 26 I built, and they were appropriate for that hull.

I've never tried for 80 so this is probably way out of my league, but I also usually run the tabs closer to the center.



Sent from my iPhone using Tapatalk

[kfxguy]

I think longer tabs will be a good start. Although the ones you have could work, they seem a bit small for that hull. I used the same ones on a df 26 I built, and they were appropriate for that hull.

I've never tried for 80 so this is probably way out of my league, but I also usually run the tabs closer to the center.




Sent from my iPhone using Tapatalk

Well honestly I don't know which direction to go on the tabs so I just ordered longer ones and I'll drill several holes to find which mounting position it likes better. I look at a few rtr boats and their tabs are to the outside and I've looked at some 1:1's and they are to the outside. You guys already know how I am, I'll find out for myself through trial and error. I've got another rudder on the way (thanks appophis!) so I'll be getting back to it as soon as I can. I'm not sure when that will be, it's been raining and I have to work late and then we have a Cub Scout camping trip this weekend. They are supposed to have a big lake there but I'm not sure I want to bring any boats and take away from my kids camping trip. I guess I'll make that decision at the end of the week.


I agree with what flraptor is saying, when its aired out, when would the tabs touch further out......but on the other hand, all the boat pics I've been seeing have the tabs further out.....but one fact that isn't been taken much into consideration....all of those boats with the tabs further out aren't going as fast or trying to go as fast as I am. They are set up for turning, so like flraptor said, the rules change. You guys will be happy to know I ordered some turn find too haha!

[rearwheelin]

Some boats like them out , some don't ! No doubt you will get it !