Reply With QuoteOh no! you've succumbed to posting on message boards. What happened, sell your planes and now you're bored.
Good to see you out here. I'm sure the info you can provide will prove to be invaluble to those who frequent this board.
Vdriveracing------Put a flatbottom rudder (drag boat style) on your 21' and it will solve your problem. It will also pick the bow up a couple of inches and free up your boat for more speed. When I built my first 21' Day Cruiser I ordered a cruiser rudder and it pulled very hard to the right. I went back to the shop and put on a heat treated steel drag boat rudder and solved the problem. All boats including Hydros only know how they are goin to ride according to the leading edge design (slant). Care less about the back of the rudder, its the leading edge slant that determines the ride.----PALHAL
Oh no! you've succumbed to posting on message boards. What happened, sell your planes and now you're bored.
Good to see you out here. I'm sure the info you can provide will prove to be invaluble to those who frequent this board.
I went to Barber Welding yesterday and Kent Santos gave me some pointers on how to read the path of the prop wash. Clear as day once he showed me the rust pattern. The "nose" at the front edge top of the passenger side was full of deep rust, while the same area on the driver side had a light trail of rust. This indicates that the left hand prop wash is pushing hard on the top/front/right side of the rudder forcing the rudder into a right hand turn.
We also noticed that the prop wash was coming up the driver side of the rudder, in about a 4" path, landing hard against the driver side trailing edge; again, for the rudder to make the boat turn right.
Kent and I agreed on some mods, including removal of the knife edge on the front. In all we hope to remove some of the material catching drag and forcing right turn, and in addition reshaping the leading edge to reduce overall drag with the rudder in the neutral position.
The folks at Barber agreed to keep some rudders on hand, just in case!
If you really want to run with a straight rudder you have to set your boat up with the prop shaft running sideways a little. On a left hand prop you put the strut 1/4 to 3/8" to the right of center line and the v-drive 1/4 to3/8" to the left of center line. You will then run with a perfectly straight rudder. I did this 35 years ago on Hydros & Flatbottoms.
Next time you are at any Hydro circle races, look at the prop shaft from the rear of the boat, especially the Unlimited Hyros. The shaft is installed sideways bigtime. All propeller driven airplanes run the engine and prop sideways so the verticle fin can run straight for more speed. This was figured out in the 1920s!-----PALHAL
If you really want to run with a straight rudder you have to set your boat up with the prop shaft running sideways a little. On a left hand prop you put the strut 1/4 to 3/8" to the right of center line and the v-drive 1/4 to3/8" to the left of center line. You will then run with a perfectly straight rudder. I did this 35 years ago on Hydros & Flatbottoms.
Next time you are at any Hydro circle races, look at the prop shaft from the rear of the boat, especially the Unlimited Hyros. The shaft is installed sideways bigtime. All propeller driven airplanes run the engine and prop sideways so the verticle fin can run straight for more speed. This was figured out in the 1920s!-----PALHAL
Interesting concept. Change the angle of entry... Hmmm:devil:
Oh no! you've succumbed to posting on message boards. What happened, sell your planes and now you're bored.
Good to see you out here. I'm sure the info you can provide will prove to be invaluble to those who frequent this board.
Sked---I didn't know you were on this site. Still have planes and for sure not bored. This has been my busiest year ever. Was just looking at this site and saw questions about things where I have been there and done that.----PALHAL
Well, I have the rudder back. here are some pics.
http://www.***boat.com/forums/attach...1&d=1190177043
crummy pic, but shows the edge feathered about 1/4" back from the trailing edge.
http://www.***boat.com/forums/attach...1&d=1190177147
I drew lines that outline a dish pattern about 1/32" deep
http://www.***boat.com/forums/attach...1&d=1190177295
red lines show slight contour added to relieve the top right leading edge
Idea here is to relieve the "hot spots" where the prop blast is building up on the rudder. Still time to test before Ming!
Posting Permissions