Fair enough and I also agree that I want nothing more than to see that miss bud acting proper in the water. I also agree that seeing how many factors it takes to get a hydro to run right takes time and understanding so I need to start with the basics from what was said. Finding cg, ditching the stock turn fin and rudder. Now my question is with what was mentioned above with chopping off and redoing the rear wing and tails is it necessary to lop them off? I would think that alot of unnecessary weight is added over the rear with that setup? Are 3 blade props more suited to hydro? Or is a 2 blade cleaver better? I dont want to give up on the hydro as I've been searching for one for the past 2 years
Okay, I'm going to take these one by one so just bare with me on this:
Fair enough and I also agree that I want nothing more than to see that miss bud acting proper in the water. I also agree that seeing how many factors it takes to get a hydro to run right takes time and understanding so I need to start with the basics from what was said. Finding cg, ditching the stock turn fin and rudder.
And most of that was addressed by some of us in previous posts. What wasn't said is how similar some of these factors are to setting up an airplane. An improperly balanced airplane is doomed to crash. In fact, in the owners documentation that comes with a plane like a Cessna 172 Skyhawk, it actually gives a chart that shows where the weight needs to be located in that airplane to fly properly. To be outside of the given range, you're looking at an unstable aircraft that is looking for that little issue that will put it out of control and into the ground. This is the situation we have to deal with when building and setting up a boat.
Now my question is with what was mentioned above with chopping off and redoing the rear wing and tails is it necessary to lop them off?
In a word, NO. What the guy in the other thread did was to cut the tails off roughly an inch above the deck. While this helped with the weight issue, it had a negative affect on the boat's stability. I know some of the limited class manned boats don't have tails at all and none have the wing. Many R/C hydros also don't have tails or a wing. Truth be told, they are just aerodynamic drag. With the unlimited boats, the tail(s) was/were added to help keep the boat going straight. This was due to a previously unknown reaction to only half of the prop being in the water that became known as "prop walk". Long story short, while the prop is pushing the boat forward, it is also acting like a paddle wheel and pushing the boat's rear to the side. That is why full sized boats turn left and our models turn right, to take advantage of the propwalk. The wing was added to the Pay'N Pak in 1973 as a way to help stabilize the boat and keep it running level. It performs the same function on an R/C. Why I said he should have gone all the way to the deck and added lighter ones is the wing and tails on the Bud are heavy. An aftermarket set from someplace like R/C Boat Company are thinner and lighter, keeping the weight down and still doing the job
Are 3 blade props more suited to hydro? Or is a 2 blade cleaver better?
Either one will work. There are trade offs with each. A 2 blade can be faster in the straights due to less weight, less engine load and less propwalk. I know my scale Elam has a bit of left rudder set in to keep the boat going straight just for that reason, running a two blade Prather prop. A 3 blade, on the other hand, can make a boat turn tighter but will cost a bit of top end in the straights due to the same factors being reversed when compared to a 2 blade. Due to a more pronounced prop walk, a bit more left rudder needs to be set in to keep the boat going straight, adding hydrodynamic drag