JAE21OB help needed

[Carl Van Houten]

Put a 1740-3 on your boat and see how well it does.

 

[XtremeRcBoats]

Nice work Mark.

Is the 1740-3 also the prop to have for the JAE OB? I still have them from my sundowner OB rigger.

 

[Carl Van Houten]

I was recommending the 1740-3 for the outboard hydro. That prop works good. Others may work as well too but most people were running the OB hydros ran that prop or a slight modification of it.

 

[MarkScott]

Latest update on the boat.

The rudder holder was strengthened with a 1mm carbon fiber sheet, layer of Kevlar in between the CF sheets. Not as strong as I'd like, but it does work. Steering was an issue on Thursday's practice. Removed the the wood for the steering servo. Glued in 2mm CF to the floor. Made a mount from aluminum angle and secured it with Savox screws. Steering was vastly improved today.

Bought two 1740-3 raw. Was able to sharpen and somewhat balance one of them. Used the prop on the second run today and cavitated. Most likely just an motor height adjustment. Went back to the prop that I know works at this setting, 1619. Boat was on rails and once the flow setting was found, it was moving. Certain there is more to be found. What was found was bouy 6 and busted spoon rods. Lucky I have a spare set at home. Wish they were at the pond. But that is why I brought three other boats to run.

There is a future project, so this is somewhat of a test bed. There's one more change to this setup I want to try. Think I need to talk to someone. Most likely will be making a call in a few days to gain someone's knowledge.

 

[MarkScott]

Better shot of what it all looks like without the motor/pipe in the way. This was before adding the 1mm layer to the rudder bracket. Yep, that is the 1619 in the pics.

 

[Carl Van Houten]

The 1740-3 should work without issues. The three blade design is going to provide plenty of lift so you should not have any negative thrust angle in your engine. What setting works with the 2 blade will not be a good setting for the 3 blade without a change.

 

[MarkScott]

Carl, will give the 1740/3 a shot another day. The mount has very limited movement for prop angle adjustment. Before being mounted, made sure the prop angle is set at 90, bottom of the bullet is even with the ski.

 

[Carl Van Houten]

That prop is not sleek and fast looking but it will surprise you how fast it is.

 

[XtremeRcBoats]

Looks great Mark, looking forward to your test results with this prop.