45mm Props NEED HELP

[monojeff]

They are graupner 45mm counter rotating props which are going to be pushing a twin 550 brushed 32" mono which I will be using as a retrieval boat.

The motors are proboat apache 550s.

I am not sure what the pitch is on the props but it says hydro on them which I did not realize when I got them.

Can I possibly cut them down or should I get new props??

[monojeff]

I believe I found the prop somewhere and it says rise 54mm not sure if that helps.

[sailr]

They are most likely 63 or 64mm pitch. If I were you I'd go ahead and try them. Run for about 45 seconds and then bring boat in and check temps. If too hot, get smaller props.

[monojeff]

They are most likely 63 or 64mm pitch. If I were you I'd go ahead and try them. Run for about 45 seconds and then bring boat in and check temps. If too hot, get smaller props.

Yeah I think your right on that 62-64mm pitch from what I could gather.
You think I should test them under load of pushing something or test without first then test while pushing or pulling a boat.

[monojeff]

Any thoughts on how many amps you think I will be pulling?

[U1Racing]

Jeff, what are you planning to use as a rig on it to hook the boats to it??

[monojeff]

Jeff, what are you planning to use as a rig on it to hook the boats to it??

I plan to make some sort of arms on the front of the boat to push them back to shore.

[sailr]

Not sure how you would test other than on a boat! Any other test would be inconclusive.

Yeah I think your right on that 62-64mm pitch from what I could gather.
You think I should test them under load of pushing something or test without first then test while pushing or pulling a boat.

[Boaterguy]

If it is a rescue, speed shouldn't be a problem, you could lower the cell count or something in order to bring rpm's down, propping then wouldn't be a problem.

[egneg]

You could always run them through a gear box which will decrease rpm and increase torque.