Sport 40 Hop and Prop test.

[Samuel Hagan JR]

Did some testing today with props and other stuff and I noticed the boat hops in the straights. Rides smooth as silk in the turns.

I noticed the boat hopping significantly went away with a prop I worked on. It still hoped but picked up a great amount of speed.

What are some other ways to get rid of boat hop?

 

[julianconde]

Prop has too much lift. Kill the lift from the propeller and add tip cup for speed.

 

[Samuel Hagan JR]

How do you get rid of lift on the prop?

I cupped the prop I worked on and gained 4 mph. I just need to get rid of the lift.

 

[glenng]

Samuel, I'm FAR from an expert but my spt.40 was running pretty "loose". It never blew off but I thought more weight in the front might settle it down- WRONG- it just slowed down and started hopping in the straights. I'm going back to the old setup-about 4 Oz. lighter on the nose. If you tell folks what prop you are using they may be better able to help. I used a X448/2 @ 4300 Ft elevation.

 

[Samuel Hagan JR]

Props I started with are

S/B X447 2 blade 54 MPH..... little hop

Sholund X447 3 Blade

5.29 cup

3.55 Pitch

45.86mm dia. 57 MPH.... Ton of hop

X450 2 blade with some mods and cup. 58MPH.. Little hop.

Mark suggested a long time ago a X450 3 blade. I'm going to try the same modes I did with the 2 blade and see how it does. I'll post pics of the X450 2 blade.

 

[FloridaScaleBoater]

Just my opinion,,, but 3 bladed props will have more lift than a two blade.

To reduce lift, take some material off the trailing edge, more from the hub end and tapered to full blade at the tip

Be sure the blades are thinned and sharpened properly, a thick dull blade will create problems also.

 

[Samuel Hagan JR]

Thanks.

I'm pretty happy with the result of the prop I did. It's no Sholund prop but it works.

 

[Duck899]

Sounds like your X-450/2 works well.

When I ran my Mutt with an AA45, I had my boat set up initially as the instructions said. But, being at 2200' elevation with trips to Calgary and 3200' there was no way to properly pull a 1455/3. I ended up using a 1455/2 with added cup. I had awesome RPM and therefore speed. Boat was very forgiving at 3200'. As the years went by I ended up with a bit more angle in the strut and the boat would literally fly and when it did it flew level. Of course you need to be on the water to generate speed. I tried to run the 1455/3 and although the AA would pull it, it had the terrible hop. I would have had to flatten out the strut but since it was already plenty fast with the 1455/2 at 3.3" pitch, I left it alone. I just ran 65% nitro for more speed.

So, whatever works best, use it.

Flatten out your strut slightly a degree and get more speed with less hop. Balance the hull with some weight if needed, worked for me.

 

[Ray Sametz]

Sam, try dropping the strut a 1/16 and run it, before you tweak on the prop............==={}

 

[SayMikey]

Is the bacl of the boat hopping or the whole boat

 

[shoboat]

Samuel,

Send the X-447/3 back to me and I will fix your lifting problem.

You may want to try the X-450 @ 5.00" of cup.

Your strut has too much angle I would bet? 4 degrees is way too much!

Flatten it out and see how it runs again Samuel?

Thanks,

Mark Sholund

 

[Samuel Hagan JR]

Samuel,

Send the X-447/3 back to me and I will fix your lifting problem.

You may want to the X-450 @ 5.00" of cup.

Your strut has too much angle I would bet?

Thanks,

Mark Sholund

The strut does have to much angle. I talked to Doug the designer and I have adjusted it. The strut angle was at 4 degrees.

 

[Samuel Hagan JR]

Is the bacl of the boat hopping or the whole boat

I can't really recall Mike. I think the whole boat.

 

[SayMikey]

Raise the strut a very small amount at a time till it stops

 

[Samuel Hagan JR]

Raise the strut a very small amount at a time till it stops

All over it. I got all the bugs worked out today. She's ready to rock for Evansville.

 

[shoboat]

Samuel,

What propeller did you end up with after testing?

Curious,

Mark

 

[Samuel Hagan JR]

It's a X450-2 blade that I cut on. I removed a lot of prop.

First time out it did as expected. Slow.

After according to my Uncle, I improperly cupped it, lol, it did 58mph. The ears are bent. I don't know how to use the prop anvil properly yet.

 

[Jim Angier]

Hello Samuel

On my sport 40 I use a 1455 3blade and it works really well

 

[Samuel Hagan JR]

Hello Samuel

On my sport 40 I use a 1455 3blade and it works really well

That's what Duck said also. I'm broke so I'm just gonna play with what I got. I'll get one soon. i would also like to try a X-648. I have a X450 -3 blade that's new I got a while back. I'm gonna work on it and try it out.

 

[Samuel Hagan JR]

My strut angle is the big problem. I measured the angle last night at its a lot. I'm going to take 1 degree out of it and keep the strut at the same depth which is 13/16".