ABC high pitch props

[kfxguy]

Rake is new to me. I don't think Octura even mentions rake in their specs. Would someone explain it to me. I might like to try ABC props soon.

Let's see if I can sum this up for you.

Octura is more or less a "general" or "sporting" type prop compared to abc. Not to say they won't go fast because yea they will. Abc is more targeted at going faster and giving you some "tweaking" choices. Now this is just what I've experienced.
Rake refers to how much the blades are angled to the rear. A higher rake means blades angled closer together which tightens up your thrust cone and creates more bow lift. The new abc props are modeled after full size race propellers.
Here's an example of rake. One is a m645 octura and the angled back one is an abc 1815-17-45

[Mxkid261]

Wow that is quite the difference. So what is the advantage of having more rake? Like in a mono application where stinger/strut adjustment is minimal, but you want more "bow lift" ?

[kfxguy]

Wow that is quite the difference. So what is the advantage of having more rake? Like in a mono application where stinger/strut adjustment is minimal, but you want more "bow lift" ?

More rake would loosen it up and it concentrates the power cone tighter so in theory the forward movement should be great (=little faster) which is what I've experienced. The comparable props between abc and octura, m645 and abc 1815, the abc has proven to be about 6mph faster with less pitch than the m645. And pulled 17 less amps.

[Mxkid261]

Have you ran the abc's on your cats? Might have to try one that is comparable to the m445, I got one like you recommended and boy what a difference it made compared to the CNC prop.

[Jamey]

More rake would loosen it up and it concentrates the power cone tighter so in theory the forward movement should be great (=little faster) which is what I've experienced. The comparable props between abc and octura, m645 and abc 1817, the abc has proven to be about 6mph faster with less pitch than the m645. And pulled 17 less amps.

I think you meant abc 1815

[kfxguy]

Have you ran the abc's on your cats? Might have to try one that is comparable to the m445, I got one like you recommended and boy what a difference it made compared to the CNC prop.

Yes. I think I've mentioned this before. An abc, say 1815 or 1915 slips or cavitates a bit on my mono when taking off. It does not do that on my cat (that I no longer have). Here's a couple videos to compare.

Mono:

Listen to when rpm drops....

http://youtu.be/2w5EXLJuEgs


Cat....

http://youtu.be/GlWajwBlup4

[Jamey]

Have you ran the abc's on your cats? Might have to try one that is comparable to the m445, I got one like you recommended and boy what a difference it made compared to the CNC prop.

I went from a m445 to a 1914 (48mm) and picked up 7+mph on my pursuit. But the more comparable size would be the abc 1814. Both the 1914 and 1814 are the older style 10 degree rake. Can't wait to try one of the new 17s.

[zooma]

I have been having trouble with my P class Pursuit flipping, particularly when crossing another wake. Would higher rake make that better or worse? Also, are these high rake props mostly for SAW or still OK for oval racing?

[kfxguy]

I have been having trouble with my P class Pursuit flipping, particularly when crossing another wake. Would higher rake make that better or worse? Also, are these high rake props mostly for SAW or still OK for oval racing?

I can't say that I would because if you slow down too much it starts cavitating. I guess you could try it tho. If you don't drop below 20 mph you should be ok

[Jamey]

Zooma, i dont race but run oval playing and i think you will be fine but you would just need to try one and see what you think. You are running a m445 now right? The 17 rake props are 1.5 pitch and up so you might need to drop down to a smaller diameter. Maybe test a 1715-17 see how you like it and how the temps are.

[dasboata]

I have been having trouble with my P class Pursuit flipping, particularly when crossing another wake. Would higher rake make that better or worse? Also, are these high rake props mostly for SAW or still OK for oval racing?

Go back to octura or lower your strut to put the bow down !!!

[oscarel]

James, here's the video from yesterday.

https://youtu.be/iO1xicAAY60
https://youtu.be/fmkKmtgJUHo

[srislash]

James, here's the video from yesterday.

https://youtu.be/iO1xicAAY60
https://youtu.be/fmkKmtgJUHo

A little bit of trim tab would go a long way on settling that hull.

[Jamey]

Thanks Oscar!

I have got some room to play with battery position still and I also had a little bit of positive angle on the strut I needed to take out. The batteries were moved forward for the second run. You can tell it helped but not quite enough. I can't really get on it wide open but the very first pass. After that the wakes are just too much for it. The max speed was about 64mph yesterday. By the way after both of those videos my cells were still at 3.93/3.94v . My amp draw has got to be fairly low.

[dmitry100]

dasboata: Are the blades of the ABC props supposed to be alot thicker compared to octura's especially after they have been S/B'ed ?

[zooma]

Go back to octura or lower your strut to put the bow down !!!

Yes. Staying with M445. Also, moved the CG forward and that seemed to eliminate the flip. Got several runs today at the club pond, and no flip. It may be a little slower, but it's more important to finish a race and let someone else flip for a change.

[dasboata]

dasboata: Are the blades of the ABC props supposed to be alot thicker compared to octura's especially after they have been S/B'ed ?

On the bigger 2.7 & 2.8 yes, but not on these small guys, except for there H series, and some of the round ear props

[dmitry100]

You mean the 1715 and 1815's ?

[dasboata]

You mean the 1715 and 1815's ?

No,,,,,,

[kfxguy]

I have been having trouble with my P class Pursuit flipping, particularly when crossing another wake. Would higher rake make that better or worse? Also, are these high rake props mostly for SAW or still OK for oval racing?

I ran an abc on my voracity last night. It does fine going around an oval. So yes I think you'll be ok.

[zooma]

I ran an abc on my voracity last night. It does fine going around an oval. So yes I think you'll be ok.

Thanks. I got a major improvement by moving cg forward. Changing props is lower priority right now, since I am setting up a Q class Ariane 2. I will probably want to try an ABC on that later on. It's a larger version of the Pursuit. I am watching the Voracity threads, though.

[kfxguy]

Thanks. I got a major improvement by moving cg forward. Changing props is lower priority right now, since I am setting up a Q class Ariane 2. I will probably want to try an ABC on that later on. It's a larger version of the Pursuit. I am watching the Voracity threads, though.

Just wanted to let you know since I ran it hearsay evening. I've mainly been using them for saw props but as I saw yesterday, it's I good oval prop with more top speed and doesn't give up any handling.

[Jamey]

A little bit of trim tab would go a long way on settling that hull.

I finally got around to doing what you suggested and you couldn't be more right. I never messed with them because I thought they would slow it down. It is crazy such a small adjustment would make such a big difference. With no tab I got a new best of 66mph but it is like an airplane wing with no boat in the water. Even with the batteries all the way forward it wants to blow over. Not really very useful or fun to tell you the truth.

With the tabs down a very small amount it is like another boat. Very steady with speeds still 60+. More to come.

[zooma]

I finally got around to doing what you suggested and you couldn't be more right. I never messed with them because I thought they would slow it down. It is crazy such a small adjustment would make such a big difference. With no tab I got a new best of 66mph but it is like an airplane wing with no boat in the water. Even with the batteries all the way forward it wants to blow over. Not really very useful or fun to tell you the truth.

With the tabs down a very small amount it is like another boat. Very steady with speeds still 60+. More to come.

Thanks. I know to start with the tabs level. But I don't what to do next. I wonder if I can now drop the tabs a bit, and then move the CG back a little to pick up my speed.

[srislash]

I finally got around to doing what you suggested and you couldn't be more right. I never messed with them because I thought they would slow it down. It is crazy such a small adjustment would make such a big difference. With no tab I got a new best of 66mph but it is like an airplane wing with no boat in the water. Even with the batteries all the way forward it wants to blow over. Not really very useful or fun to tell you the truth.

With the tabs down a very small amount it is like another boat. Very steady with speeds still 60+. More to come.

Yup, I fought with my DF35 (and myself) for the better part of a year using the same reasoning but alas, just a touch of tab and she is beauty.

[Turbo Dan-O]

So, I would like to try out one of these ABC props on my Pursuit. The M445 runs really good on mine so far and I don't want to get too far away from that. Would the 1715-17-45 be about right?

[MG1234]

I hope you can help me I need a prop and still learning ,HK genesis ,4092-1750kv,6s ,445 OSE aluminum prop,strut is all the way up and I dremmeled anouther 2 mm up,I want a faster prop but need one balanced and ready to run ,what would be a little faster,little more load on the motor,prop?i off set the rudder and read that I should put it back straight ,I can run hard for an entire battery with decent temps ,so my next step up would be? I like the example if the ABC props,help please I want to have a new prop next weekend ,

[dasboata]

I hope you can help me I need a prop and still learning ,HK genesis ,4092-1750kv,6s ,445 OSE aluminum prop,strut is all the way up and I dremmeled anouther 2 mm up,I want a faster prop but need one balanced and ready to run ,what would be a little faster,little more load on the motor,prop?i off set the rudder and read that I should put it back straight ,I can run hard for an entire battery with decent temps ,so my next step up would be? I like the example if the ABC props,help please I want to have a new prop next weekend ,

Find out what OSE guys suggest and I can help you out with the b/s prop my suggestion would be a reduced 1914 ,,thanks chris

[MG1234]

They suggested an M 447 so I ordered it ,I don't know how to sharpen or ballance ,and in 2 mo the boat season will be over and I'm back at the track ,I snap shot your message and save them for future reference ,I asume the 1914 is an ABC prop? Would it be faster or slower than the M447? In case it's too much for my boat I'll know which way to go ,thank you for your help ,it's great fun going fast ,

[kfxguy]

Got a big-en in today from ose