Maidened my Daytona today- some setup tips appreciated.

[kwiktsi]

Before I get too far into changing things, is this a common issue with this hull? I am running a single 4082 1600 on 6S, the strut is even with the bottom of the sponsons, trim straight, 45mm CNC prop and the rudder is 3 5/8". Part throttle, half throttle, whatever- boat is straight. Full throttle, it prop walks bad enough that the boat would drive in circles if I let it. I have to hold at least 1/2 turn left to keep it straight! Where should I look to resolve this? I have read bending/shimming the strut to the left, sharpening the prop, etc. but don't want to bend anything if it isn't necessary. The prop is pretty sharp as well and does not have an issue at all on my Pursuit with the same motor. I wouldn't think the 45mm diameter is too much for this hull? This is the first time I have had a boat pull so bad, so I figured I'd get some advice here.

Also, is there a disadvantage to running the steering servo in the left sponson? I was thinking I might as well get it down as low as possible and thought that with it on the left, it would help counter the torque vs. putting it on the right. Figured I'm going to be painting the boat anyway, so it's worth experimenting a bit and if it doesn't work, I can just fill the linkage hole and move it. Any opinions?

This boat is pretty tippy in the turns, if I maintain speed, it's *ok*, but if I back off the throttle too much in the turn, it just rolls right over. Going to take some getting used to. Kind of wish I went twins with it, help keep the weight low because of how narrow it is.

I'll be posting some pics in the build section shortly if anyone is interested. Thanks in advance guys!
Joe

[jetnfast]

After 7 runs with my Daytona, I have noticed most of the same habits your boat has. It does have some prop walk to the right, but I just compensated with a little left rudder when I add power. Its become almost muscle memory for me. Its a lot like flying a full size airplane, you have to add rudder to counter the p-factor. Same principle, but when applied to boats means adding some left rudder.

[kwiktsi]

What size prop do you have on yours? Mine is worse than I've ever experienced before with any other boat, so this is new to me. I don't mind giving some left turn/trim to it, but it is BAD. I went back out a little bit ago with it and it literally is over 1/2 turn to the left to keep it straight! That is a lot of drag at that point as well. I am going to drop down a couple of sizes in prop and see if it helps any, but with the 1600kv, I was hoping to pull 45-47mm props on it on the 6S setup. Thanks.
Joe

[Rocstar]

Joe, it should't pull that hard. Do you have any pics your setup? Is it running wet at all?

[kwiktsi]

To me, it looks to be running a bit wetter than I'd expect it to, but I don't know how this boat normally rides. I tried raising the prop as high as it would go before hitting the bracket and it still acted the same. Don't get me wrong, it's not plowing through the water or anything, just doesn't look or feel as loose as I had expected. Should I try to drop the prop down some? This is where I was always confused- I had always been told that dropping the prop will lift the hull higher, so that is always what I had done and thought it was working for me lol, but here I always read the opposite. Now that I think about it, I don't recall the pull being as bad with the strut down flush with the sponsons as it was when I tried raising it higher. Maybe since it is higher, it is out of the water more and contributing to the prop walk? How about the CG? Where should that be on this boat? I have it about 9" from the end of the sponsons.

Would the servo in the left sponson affect it any? I figured it would help counter the torque roll there vs. contributing to it on the right side.

I have attached some pics that I just snapped, if you need others with the shaft and prop installed and such, let me know. Thanks Joel!
Joe

edit- I am leery of having the bend in the rudder linkage, only did that because I had seen many others with similar bends and they seemed to be fine. It is fairly rigid and steering response is strong at speed, outside of the pull. Wondering if that could be contributing though. Maybe I'll cut a wood servo mount and lay the servo flat in the center of the tunnel.

[tiqueman]

Joe, If you hold the servo arm from moving, can you twist the rudder and make the pushrod flex? Ive built SEVERAL of these, they all have the spinning hooking and rolling over syndrome, especially when coming off the throttle slightly into a turn. All that Ive done, I typically keep the pushrod exit as close to the rudder extension as possible to keep the bends in the rod to a minimum. Id start there, but the hulls do have a slight tendency to pull. The weird thing about hulls are, you can build two exact boats, exactly the same yet they can "feel" totally different. I don't have any in my arsenal any more, but about 9 on the cog sounds about right from what I remember. Ill have to do some digging to remember where my strut was, I know I ran them neutral and I think it was just above the sponson bottoms. I ran the same power set up in two of my personal hulls, but used smaller props. If you search Bill34207 on youtube, go back a couple years and you can see mine as well as Chris's and Bills "Genes-I" running the course to get an idea of what ride attitudes we had on ours.
Hope at least some of that helped
Scott

[ozzie-crawl]

I would say the steering rod is to blame. Had the same issue a few years back with the apparition cats. If you can put it in the right side sponson and have the rod pulling the rudder right instead of pushing the rudder is much better and causes no flex of the push rod.
Mine runs a 1515 1y on 4s and I have found so far more pitch less dia seems better.

[martin]

Yep that steering rod is next to useless with those bends, hold the servo horn & see how much movement you get pushing the rudder side to side with your fingers.

[Rocstar]

I would have to agree that your linkage rod is contributing to your problem. I would suggest moving your servo and keeping the linkage rod bends to a minimum.
Scott is right, no two hulls run the same. I had my strut just above the bottom of the sponsons with a little negative and the CG further back.

2012-07-21_17-30-18_713.jpg

http://www.youtube.com/watch?v=UbiLR_JiBY8

[kwiktsi]

No problem to move the servo and try a different exit. I was just trying to keep it as low as possible. That and there was no room for my nifty boot holder that I made next to the rudder bracket on the transom lol. If I hold the arm it really does take some effort to get the rod to flex, much more that some of my boats using a smaller diameter straight rod, but those are pulling, not pushing so that may be part of it.

[kwiktsi]

Laser cut a servo tray and moved the servo to the center with the rod going straight to the rudder. I was able to turn down the stub I made to hold the linkage boot so it fit as well. Going to take it out tonight to see if it helps. I was hesitant to put the bends in the arm like that but have seen many pics of them with similar setups so I just figured it wasn't as big of a deal as I thought it was. I plan on trying some other props as well, so I will post back later after running it.

The hooking and rolling has me a bit uneasy about running it. Going to take some serious seat time to get comfortable with this hull to find where that line between turning and rolling is!

[kwiktsi]

OK, as mentioned above, I moved the servo and changed the linkage to a straight setup. As I suspected it would, it made absolutely no difference . I dropped from the 45mm to an x440 and completely different boat! Lost some of the punch it had, but just a touch of trim and it goes arrow straight at full throttle. I was really hoping I could get away with a 45-47mm on this boat as that would be a better match for this motor. I have a 642 here that I am going to try next time out, hopefully that will work out nicely for it- give me my speed AND not prop steer nearly as bad as the 45 did.

If I wanted to run bigger props, is it acceptable to shim/bend the strut to add some left thrust? I have seen some mention of it over the years and it's what we do with the planes to keep them tracking straight at full throttle. Or should I just stick to the smaller props and be happy with it lol?

[ozzie-crawl]

Try more pitch. I have run a 642 with mine (2200kv on 4s) and don't have any issues pulling right.
I am actaully about to build a 2nd one. Looking at either another 1515 1y on 5s ( already have the motor) or trying lower kv more voltage setups.
Want to try lots of rpm and small props.

[ozzie-crawl]

Intrested to see how yours goes with the inline rudder. I could never get them to work well a few years ago, very twitchy and squirrely at high speed.
Be nice to see it work work with this hull as I qm not sure a offset rudder won't cause problems at high speed

[kwiktsi]

Try more pitch. I have run a 642 with mine (2200kv on 4s) and don't have any issues pulling right.
I am actaully about to build a 2nd one. Looking at either another 1515 1y on 5s ( already have the motor) or trying lower kv more voltage setups.
Want to try lots of rpm and small props.

Thanks, I'm hoping my 642 is the ideal prop for this setup. I was really hoping that I would be able to run a 47mm or so on this boat. I would have gone higher KV and smaller prop, but I plan on running 8S on occasion for some real speed runs, so I wanted to stick with this motor. Helps that I'm familiar with it's power output from running it in my Pursuit.

Another thing I forgot to comment on, it did not seem to hook and roll today like it did before (I rolled it 5 times in one run yesterday ). I don't know if getting the servo/weight out of the left sponson helped, the smaller prop not suddenly shifting from rolling it one way to braking and torquing it over the other direction or a combination of the two but it was much more manageable today!