A different Rudder Placement question (Advice appreciated)

[Sonic24]

A different Rudder Placement question

I have searched through the forum for an answer to this question, but have not found what I am looking for. There are many discussions about offset rudder placement, and only a few asking on this topic with no solid responses offered.

I am still new to FE boating, so I apologize if everyone already knows this; but…

I am building an FE boat from a blank hull I purchased on ebay. I think it was intended to be a gas boat, but I am building it for electric power. The boat has a flush transom (i.e. no overhang). The rudder I chose is a short base. The stingers I chose put the props ~3” behind the rudder’s leading edge. In looking at pictures on this forum I have seen rudders mounted in front of the props; but not this far. It wasn’t until I was assembling the transom hardware that I noticed this alignment. I stopped and started this investigation.

Rudder placement in relation to the props?

I could make an extension for the rudder, but that large of a block would need to be aluminum and the weight may throw off my planned center of gravity.

Advice would be appreciated.

Details on the build:
Cat hull is 42” x 16” with a flush transom (i.e. no overhang)
6s Power
Twin Swordfish 300 amp Pro+
Twin TP Power 4070 1650kv
¼” drive cables

[Fella1340]

Can you post any pictures showing the transom of the boat and the hardware mounted? It sounds like a rudder standoff may be in order, I wouldn't worry at all about balance or COG considering. The hull size and all the goodies you have stuffed inside. Pics would really, plus you can show off your boat. An interior shot would be cool to. The extra eyes and experience in this forum may just help you locate any potential issues before you hit the water. A good idea imo.

[tlandauer]

What he said!
I had a similar issue building my H&M Intruder S Twin. I have asked a few people and the general feedback was that if the rudder base is a bit shorter and the leading edge is ahead of the drive dog, it is probably still OK. The worry here is for the turning ability of the boat. Three inches is more than I would want but I am sure more experienced guys could chime in.
I had to build a stand off and readjust my COG, but that is not a difficult part. During your build process you should always be flexible and deal with unexpected issues like this, so don't glue everything down inside first, have all the necessary hardware items either mounted or double side taped outside the hull so you know what to expect.
DSCN7333.jpg DSCN7616.jpg

[Sonic24]

Pictures included

Good advice Fella1340 and tlandauer. I had actually read the thread about your H&M Intruder during my search.

I temporarily placed the power train in the hull for these pictures. I have not yet mounted the servo nor drilled the holes for the rudder linkages. They will be mounted much like the H&M Intruder pictures above.

I probably added more pictures than needed, but hope someone can offer advice.