Ok so I am gonna start building my mini and I am using a 2AO42 engine and trying to figure out the best prop. So I called arrow and they told me a 40"? Can any of you more experienced guys help me out with this? Thanks in advance for your help!
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Ok so I am gonna start building my mini and I am using a 2AO42 engine and trying to figure out the best prop. So I called arrow and they told me a 40"? Can any of you more experienced guys help me out with this? Thanks in advance for your help!
They are going by horsepower and those motors are rated low. I'd just ask for a prop that will work with a 20-25 hp motor. It should be a 42x18 or maybe more pitch if it a narrow blade. It's really the best to have the prop maker tell you what you need because of the different designs of props. You just can't give one pitch and length for a motor that works with all props. There's just too many variables.
Ill search a bit bit and see if any of the aircraft guys have a prop listed. I have seen a few that use or have tried the 042. Another option is buying an ultra prop and trimming the length down then experiment with the pitch. The ultra prop uses pitch blocks. Some of the manufacturers will let you return pitch blocks that you don't use.
Papee thanks so much for your time and knowledge I just didn't want to invest in the wrong one! With the ultra prop will that hold up to the high rpms of direct drive?
You should never have high rpms. If you do you don't have the right prop. The prop is actually a 'governer' for the motor slowing it to around 3100 rpms. That's the goal when setting up a prop direct drive, find the right prop that will turn at 3100 rpm when you are at full throttle with your motor.
You ou have to check manufacturers though, some recommend a slower rpm but most are good to 3100.
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I think I will go with the ultra prop being I can change the variables somewhat. I found this old picture and was wondering if you know where to get the hub to mount the prop? Will an ultra prop mount to a 1" shaft?
The ultra prop has slotted mounting holes. I got the hub I was using there from arrow props. Took me a minute to figure out that is one of my old phots. I still have that whole setup around and finally figured out a use for it. I'm looking for a cheap pontoon boat that I can build a small 'camp' on. I'll put that setup on it and use it for camping. It won't be a mover but it will get the movable camp where I want it to go.
Floating Camp sounds like a good idea. Ok cool so arrow prop can make that four bolt pattern hub that bolts to the flywheel. Is this something they keep in stock or did they have to make it for you?
No the hub fits a 1" shaft. I must have misread, I thought you mentioned a 1" shaft. I bought that adapter from 4 bolt to 1" at a local army surplus, we have two here. I think Saturn may have them though.