"game changer" propellers

[Ron Jefferson]

Went to the test pond today and had a chance to try the 1715-17 on my .21 boat. We didn't have a radar gun but the speed difference wasn't noticeable from my 50x69 3.6cup. What I did notice was that the boat was hooked up better both on the straights and in the turns. The boat has always turned awesome but with this prop the R's stayed up and the boat didn't seem to lose any mph through the turn at all. All-in-all a step in the right direction for sure. Is the 1716-17 much of a step up and are the characteristics the same as the 1715?

The 2219 on my .45 hydro was less exciting. The boat plowed around and wouldn't get up on plane. Perhaps more adjustment and test time will show better results. Is there a more suited prop for a .45?

 

[sbowden21]

ron im going to test 2219 on my 45 this weekend ill report back with my results.. anxious to see these props in heat race water, we all know practice water is nothing like race water..

 

[shoboat]

Ron and Sam,

If you guys just sharpen and balance them you are going to struggle.

They have way too much in them for heat racing. Ron the 38% blade area

Propellers are a lot different than last years 1715's with 45% blade area.

Glad you could tell the handling difference with the new propellers. I think

you guys will find that without a ski underneath your tub the 1.9 pitch ratios are

going to be a lot of pitch to pull up and down in heat racing. Most of these propellers

will work much better once you get better numbers in them. Are you guys running

Scott Bouchie pipes on your 45-Hydros yet?

If you need some help give me a call?

Thanks For Reading,

Mark Sholund

231-590-3023

 

[sbowden21]

Mark the 2219 i have you sent me last December so its however you do them... No bouchie pipe here.. the last 2 races ive had my 45 at i won both with an old pipe and a 1457 you did for me? why change whats winning? dont get me wrong i like trying new stuff but im doubting this 2219 is going to give me 8-10 mph??

 

[Ron Jefferson]

Thanks Mark. Late last season I added a centre ski to my boat which has made the launch a joke for way more prop. I still have the rears in place but ended the ski about an 1" from the transom. It acts as an aid only and doesn't come in to play when the boat is up to speed. I spun the boat out last year trying to avoid a collision at Hobart and thought it was dead in the water. I looked again and noticed the prop was still spilling water off the back. I pulled the trigger and the boat humped up and kept going. I couldn't believe my eyes because the boat was almost standing still.

I've also switched to the CMB Beta and it's performing awesome right out of the box. lots of RPM and torque with the CMB nitro pipe at 7 7/8".

Any advice and support you can offer would be greatly appreciated. Let me know what you would suggest.

Thanks, Ron

ps. The 1715 was not modded and simply sharpened and balanced.

 

[BobHorowitz]

Mark,

You have a PM from Bob H.

 

[dwilfong]

Take the whoop out of the trailing edge.

Either take a file and file it from the back side or use a dremel and grind the front side of it.

It will help unload the eng and let it rev more and launch better.

This is how you adjust the load on the eng. It all depends on how much power or nitro you have to play with.

There is a lot of cup in that trailing edge whoop.

 

[dave roach]

Ron

Try the 1716-17 prop.If you can get the 1714-17 in the 45% blade area try it.

 

[Ron Jefferson]

Dave,

Isn't the 1714-17 going in the wrong direction? Or maybe you're running a super short pipe?

 

[ABC PROPS]

Sam

You may go slower in the straight

The big thing I'm looking for is the increase in the corner and better handling with the 38 BAR and 45 BAR series

Lap speed for the heat racers is the key

Get that .45 to run a 10 sec lap (60 mph lap speed)

And we got some fun racing

Also guys

Measure the Cup(swoop) with a Dial in .001 not a pitch number

I can give you all the Dim

 

[dave roach]

Ron

Running the pipe 7 3/4 long.I am still running the Mac engine.

 

[shoboat]

Ron,

To understand why your boat just plowed around last weekend?

I measured a new 2219 today and here are the numbers:

6.92" of trailing edge cup at .7 radi on the 1/16th step on a Steve Wood Gauge.

5.29" of center of blade pitch at .7 radi on the 3/16th step on a Steve Wood Gauge.

Diameter is: 55.43 mm, this propeller has already been sharpened and balanced.

Once I take a little out of it I think it will work much better. These current numbers

are just a little too stiff for good heat racing conditions.

Just My Thoughts On The Subject,

Mark Sholund

 

[Ron Jefferson]

Thanks Mark. I really appreciate the feedback and would like to discuss the numbers with you further. I've had zero test time in the last few years due to the closing of the London pond. Last weekend was our first day out to the new practice lake and it's exciting to make progress once again. I spent most of the time with the .20 boat because I've done some mods to the hull and front sponsons over the winter. All the changes, including the propeller were a move in the right direction. Funny how you think you have a good package and there's still room for improvement. Running out of time I bolted on the 2219 to the .40 boat and didn't give it a fair chance. Next time...

I'll give you a call over the weekend to discuss.

Later, Ron

 

[lohring]

How are you suggesting that the cup be measured? Hydrocomp suggests a gauge like the picture below. Standard pitch gauges measure either the rise for a fixed rotation (Orlic style) or the rotation for a fixed rise (Woods/Speedmaster style). Except for the cupped area, the new style ABC props I've measured all have constant helical pitch with a cupped trailing edge. What is the suggested slip based on the blade pitch?

Lohring Miller



Cup Gauge



Woods/Speedmaster Gauge



Orlic Gauge

 

[ABC PROPS]

When you look at pic one

We use a 30 degree angle

Total offset of cup is a % of the DIA

2% for the 45 and 50 BAR

1.5% for the 38 Bar

We measure in .001

Slip can be from 8%-20% in our blades

 

[dwilfong]

I have used the Orlic gage with good results.

You can measure 5 deg of rotation with this gage as made. But if you use a small protractor you can get it to 1 deg increments.

The woods /speed master / Andy Brown gage will not measure the trailing edge CUP on the new props.

The TE cup is what needs to be adjusted not the pitch of the new 38 BAR props.

Use a woods gage and set the pointer at the point where the trailing edge swoop starts and see what you get........

Put the pliers away and start to check and adjust the whoop...............the GAME has changed............................

 

[Marty Davis]

I think that you will find that the props lift less at top speed. I have found the selection almost "dizzying" as Jim has provided so many choices that you will need to work in a progression of pitches in each diameter choice. No prop will suit all boats of a particular engine size, so you will have to "buy and try". I think that in my favorite class (.21 Hydro), you will find that the 17 series is a great diameter for heat racing. The 18 series is a little big for my use.

I ran one of the 17 series prototype props at the Winter Nitro Championships with good success. Was with a longer boat as was mentioned in a previous post.

I really haven't decided on the best prop at this point, but the 1717 might be my favorite at this early point.

I think that everyone will be greatly pleased with all the choices we no have.

CUDOS to Jim Shaefer for all his efforts on this project !!!

 

[lohring]

Below is my first cut at a cup measuring tool. You find the flat area on the blade and measure down to the cupped edge. The main problem was the base edge doesn't align with the measuring rod. This means you need to be very careful to hold the calipers at right angles to the trailing edge. I'll make a better version when I get time.

Lohring Miller

 

[lohring]

For some reason this file was too big to include in the above post. And of course I need to wait before posting anything else.

Lohring Miller

 

[shoboat]

David,

My Three Woods Gauges all work very well on the new game changers.

Not sure why you guys are having so much trouble? Pretty straight forward

I think.

Enjoy Testing Them,

Mark Sholund