DF Vortex 34 Hydro Build

[CraigP]

Hi All,

New to OSE, but been in boats a long time. This is my first FE build, I ran 0.40ci nitro motors in a 36" plywoodhydro hull some years back. I have some stuff stuck over on another thread, I'll copy/paste over to this. The forum scene is new to me, so just let me know if I can use it better. I have a thick skin, and love to have fun. I take this hobby seriously, but seriously folks, what's to be real serious about? It's all good! I spent close to 40 hours reading posts and learning, before even stepping out to post! Really good stuff on this forum!

[CraigP]

ProperChopper and I started chatting about this hull. Here's what I had on the other thread:

What prop did you end up with? I'm putting an 8S, Leonard 40X72 1050kV to start, then I have a 1250 40X82 motor to kick it a little harder. It's been a while for me, but I'm really looking forward to going electric, gas powered boats were a PITA! I was wondering if you could share what prop you are currently working with. I have Grim Race 38X55, 2 blade High Lift to start out with. I have a Grim Racer 40X57, 3-blade high rake prop to step it up. Is a 42X63 prop about it for this hull?

I'll get some picks on the sponson mods I'm going to be doing. The room in this hull is awesome, love that! I plan on putting the length of the four 5200, 2s batteries across sideways, just starting at the top of the hatch. They go out across the drop off for the sponsons. Thinking of mounting a floorboard for the batteries in there. I want the CG weight components split out, getting weight well forward and placing the front of the motor 13-7/8" from the back of the transom. That still leaves ample room for the ESC and Cap Board in between the motor and the battery pack. I think about CG like a teeter-totter. The longer the arms are from the fulcrum, the slower they move. When the arms get short, then the speed of the teeter-totter goes up dramatically, which represents the boat porpoising, which is not the play. I'm setting my rudder to the left like your model. That seems to make the most sense for a right turning boat running a CCW prop. Prop torque will try to pick up the left side, so setting the rudder left helps stake that side down.

Another trick I was going to employ was to shim the left side sponson up about 1/8" from the right. This really helped in GP boats for turning. My brother is still running in GPW, has a 28', 500CI blown on alcohol motor. (Check out YouTube, search for GP55) I know the dynamics don't entirely scale, but weight shift and corner planting should involve the same physics.

Sorry to load you up this way, I just loved the way your hull turned out and value your building skills and experience tremendously. One more point to ask you, strut angle. I'm looking at 17 degrees, going into a single 10" radius bend to the strut. There is something I want to try... I found that the stainless steel tubing on OSE was a perfect fit for the 0.187" flex cable without a liner. It has about 0.004 - 0.005" per side clearance, perfect for grease. The stainless has a thicker wall than the copper tubing normally used. Also, I find the "stickiness" of stainless to be far less that copper, something that is termed "stiction", so I believe it will not have a tendency to grab the cable. You think it's worth the try?

Well, ProperChopper, getting long here. I hope that we can meet up some time, I have enjoyed getting to know you some on the forum. I promise to get pics out on the build. You know I just hate stopping work to take pictures, but they can be very valuable and may help others enjoy this great sport!

[CraigP]

I made up an AutoCAD drawing showing a Side View of the drive line angle I want to use on this boat. Having it in AutoCAD let's me really explore options. This drawing will grow as the build progresses.

[CraigP]

I'm making this an 8S system. I know many of the viewers will say that's too much, but what I'm trying to accomplish is to make delivered power more with voltage and bring the current down. The secret here, in my opinion, is to select a motor that has a higher impedance than motors rated to run at lower voltages. Impedance is not resistance. It is the dynamic resistance the motor puts up under load conditions, and has much to do with both initial coil resistance and the initial coil inductance. The coil resistance is what many people see on the motor sites when they show motor specs. It has NOTHING to do with the actual impedance while running, unless the prop stops completely while still getting a load speed signal.

So, I have a Leonard 4074 1050kV motor, rated to 45V. The Leonard web site clearly shows the initial resistance higher, indicating it has more windings in it. So initial inductance is higher as well. So the key to me to making this work, it to NOT BE STUPID and put a bunch of prop, or motor load on this. I have a Seaking 130 HV, but really wished I had a Swordfish data logging unit instead. That's the only way to go! If I do this right, then I should get increase run time by dropping the current that is required of the batteries. It's better on the batteries and the whole electrical system in general. I'm using four, 5200mAH in series running to the stated motor and ESC. I do have a Leonard 4082 1250kV motor to put in there once I learn about prop capabilities on this hull.

[CraigP]

Here's a pic of the planned component placing. I can move the batteries +/-1" from there, should give me good CG tuning range... The motor is where the CAD drawing I posted earlier indicates it needs to be to get a 17 degree stuffing box.

[properchopper]

ProperChopper and I started chatting about this hull. Here's what I had on the other thread:

What prop did you end up with? I'm putting an 8S, Leonard 40X72 1050kV to start, then I have a 1250 40X82 motor to kick it a little harder. It's been a while for me, but I'm really looking forward to going electric, gas powered boats were a PITA! I was wondering if you could share what prop you are currently working with. I have Grim Race 38X55, 2 blade High Lift to start out with. I have a Grim Racer 40X57, 3-blade high rake prop to step it up. Is a 42X63 prop about it for this hull?

I'll get some picks on the sponson mods I'm going to be doing. The room in this hull is awesome, love that! I plan on putting the length of the four 5200, 2s batteries across sideways, just starting at the top of the hatch. They go out across the drop off for the sponsons. Thinking of mounting a floorboard for the batteries in there. I want the CG weight components split out, getting weight well forward and placing the front of the motor 13-7/8" from the back of the transom. That still leaves ample room for the ESC and Cap Board in between the motor and the battery pack. I think about CG like a teeter-totter. The longer the arms are from the fulcrum, the slower they move. When the arms get short, then the speed of the teeter-totter goes up dramatically, which represents the boat porpoising, which is not the play. I'm setting my rudder to the left like your model. That seems to make the most sense for a right turning boat running a CCW prop. Prop torque will try to pick up the left side, so setting the rudder left helps stake that side down.

Another trick I was going to employ was to shim the left side sponson up about 1/8" from the right. This really helped in GP boats for turning. My brother is still running in GPW, has a 28', 500CI blown on alcohol motor. (Check out YouTube, search for GP55) I know the dynamics don't entirely scale, but weight shift and corner planting should involve the same physics.

Sorry to load you up this way, I just loved the way your hull turned out and value your building skills and experience tremendously. One more point to ask you, strut angle. I'm looking at 17 degrees, going into a single 10" radius bend to the strut. There is something I want to try... I found that the stainless steel tubing on OSE was a perfect fit for the 0.187" flex cable without a liner. It has about 0.004 - 0.005" per side clearance, perfect for grease. The stainless has a thicker wall than the copper tubing normally used. Also, I find the "stickiness" of stainless to be far less that copper, something that is termed "stiction", so I believe it will not have a tendency to grab the cable. You think it's worth the try?

Well, ProperChopper, getting long here. I hope that we can meet up some time, I have enjoyed getting to know you some on the forum. I promise to get pics out on the build. You know I just hate stopping work to take pictures, but they can be very valuable and may help others enjoy this great sport!

I'm still testing props. I've used a 452/2 and a 450/3 - both Octura's. [One thing is that with the TP Power 4070, which is actually 40mm X 100mm, I could spin anything with all that (silly/unnecessary) horsepower.]

Your 8S 1050KV setup may want (at somewhere near 34K rpm) a larger diameter prop - your 4072 should be able to handle larger wheels - depends how fast ( and how long) you want to run. We're in somewhat uncharted territory with this hull - AND both Jay and Howard's V34 are (like me) rigged for 4S2P "P" Class racing so our props may not be the ones you'll do best with.

The stainless stuffing tube makes sense - theoretically less coefficient of kinetic friction 'tho in my case I've got enough HP that it won't matter much. One thing ; in your diagram your stuffing tube resembles two straight sections with a bend in the middle. Better to have more of a continuous gentle "curved" shape.

You are correct about prop torque and its effect on the LF sponson lifting. I 've added weight in the LF tip to minimize this.

[CraigP]

That's a 10" bend radius in there now, I'm going to try some bigger ones and see what it looks like. Trying to shoot for a 1.25" strut centerline depth, I think the sponson work should help make that happen. Not easy changing the strut depth once the boat is complete! I'm thinking to start at running the prop at a neutral angle, it may need running the prop down about 1.5 degree.

Yeah, my wheels are small! I have some nephews and nieces that would like to learn how to drive, so I thought they would be good learning props, for them and me! It was ALOT of work thinning and polishing those wheels, my freaking fingers hurt... Now they got that nice little "ring" to them when you wipe your finger across the edge. I'll cup them a bit after working out the CG and basics.

Actually shooting for about 26KRPM's on the 1050 motor with the prop staying hooked up. I may have to run the switching frequency at 12Khz to limit the power to the motor.

Appreciate your feedback...

[CraigP]

Here's 15" and you're right ProperCHopper, it does look more gentle. I'll have to get a big piece of tubing, that radius ends about 3/16" from entering the strut. I'll have to bend it, then cut it back...

[CraigP]

Hi All,

I've been working on my DF vortex 34 Hydro build. Going slow, been hammered at work! What's that all about? Doesn't my boss know my htydro build is more important? LOL!

I have some sponson rework pics to share with you. As posted earlier, the stock sponsons are not what I want. They have way too much lift angle, too much side angle and they "swoop up" towards to front, which makes them sticky in rough water. A long time ago, I ran sponsons like the pics and found that the boat was much more stable all around. That was on nitro, hoping the FE boat does the same.

The wooden rails put down as a base frame are made of laminating 5 pieces of 0.25"X0.25" basswood rails together with marine epoxy. They are incredibly light! I then put in fiberglass and resin inside the channels to re-enforce the epoxy bond. The actual "skin" of the sponsons is T6061-T6 aluminum plating, 0.031" thick. They are held by 4-40 brass wood screws. This thin aluminum I found holds up much better than wood, that eventually starts to show the rails through it after a couple of seasons of pounding on it.

The site won't take all the pics, so I'll put them on in separate posts.

Race on All!

[CraigP]

Second set of sponson pics.....

[CraigP]

Third set of sponson pics....

[rol243]

looks nice and neat but i wouldn,t like to race against this Iron Maiden , lol.

[CraigP]

It does have a battle ready look! All the materials added 0.74lbs to the boat. The sponson design was originally created by Ron Jones. It flattens out the angles, allowing the boat to "skip" across rougher water, like a skipping stone. When the boat hits a crest, it pops up a bit. That produces negative strut angle that brings the boat back down. The rails deepens the sponsons, which opens the air bleeds behind the sponsons. This controls the air under the boat more effectively than air dams. Air dams work to a point. Once beyond that, the boat will snap-flip because the dam itself creates additional trapped air.

[Mxkid261]

Interesting sponson work. My 24 vortex runs great in a little chop. Maybe the larger hull rides differently.

[CraigP]

I was referring to ugly race water. The other goal is WOT turns, in race water. Others on this site and other sites wouldn't put the 34 Vortex in its stock configuration into the stable category. They like to sponson walk and they run light on the front. Stock, they do trap too much air, resulting in quick executing blow overs. They also like to hook in corners when hitting side swells. This boat will skip, never getting to that sponsons never touching ride. Some say slower, I say you have to finish to win! You can't win when the boat is upside down... definitely not a SAW configuration!

[CraigP]

Here's a short clip of my DF Vortex 34 running last weekend. I lowered the strut after this clip and adjusted the turn fin. It ran much more settled than this clip. But it's looking pretty good here. It has a small motor in it now, until I get comfortable driving it. The motor is a Leopard 4074 1050kv running 8s with a SW 150a Pro+ ESC. It has a Prather S220 prop on it in this clip. It's now running a M545. GPS logged this run at 52mph, probably on the straights. I'm bogging the near corner badly, but it feels tight coming at me.

https://youtu.be/_lUkHAYp-aI

[properchopper]

Craig,

Looking good :thumbup1: Appears that the sponson mods were worth the effort. Now the next step is to put some more power to it ; The 4082 - size Leo [or the TP Power 4060] will give more top end and test the handling in what likely will be the high 50 mph's or (propped up) the 60 mph's. For reference ('tho not apples to apples) my P-Cat Cheetah (running extra loose) with the TP Power 4060 {2040KV/4S2P} routinely/comfortably spins a 450/3 and has (for 2-lap time trials) a 452/2.

Here's a completely embarrasing initial run with a 450/3 prior to adding an air dam and lowering the strut (the tail fins are to aid lateral stability at speeds over 200mph :olleyes:). Attempts at full throttle were simultaneously accompanied by a nice lakeside lunch while awaiting the boat's re-entry into the Earth's atmosphere :
https://www.youtube.com/watch?v=0Cdexf5jz3whttps://

Subsequently added air dam, lowered strut, added ballast in LF sponson tip, chickened out & throttled back to approx 1/3 throttle . Boat ran much smoother but the slower test speed really didn't indicate what would happen when spooled up but water & wind wasn't in my favor + after race guys wanted to pack up & close lake: [ speed clocked with calendar:olleyes:]

https://www.youtube.com/watch?v=qKEH2yqruDA

Now that the racing season is basically over at Legg (and the warm weather weed problem is starting to clear up ) I'll spend some more time mostly prop testing. I over-motored this build to see what the TP Power 4070 2200 KV 100mm can motor was capable of. It can likely power my Ford Explorer:ohmy:

[CraigP]

Thanks Tony, it's been a lot of work but really a lot of fun to drive! The boat shows no signs of getting "Flippy". No hooking characteristics either. As you mentioned, it time to put the proper power to it. I have a 4082 1250kv to start turning larger props. The little motor is getting about maxed out with a M545. I have a M645 to try on it when I do the motor swap. The big delay is and has been, my inability to drive the boat! Before, at 50mph, the boat was always ahead of my concentration. I'm just getting into the 60's and have to learn that level. It takes a lot of thought, I really respect the talent of the good race drivers, it's not a trivial skill!

The next step is to try a 4s setup, to see about a P Sport setup. I have some batteries to make a 4s2p, 10,000mah battery pack, it just fits. I'm getting another pack that's 4s2p, 8,000mah, a bit lighter. I have a TP 4050 2310kv motor to couple to the 4s pack. I'm currently running a SW 150A Pro+ ESC on the 8s pack, highest current has been about 90A. That's a real sweet combination! The little motor only runs about 70A, the larger 4082 ran the higher current. I have a SW 220A Pro ESC to run the 4s pack.

I ran on Tuesday and found the steering too sensitive, so I cut down the rudder some. It's a dual water port, 1/8 scale rudder (Speedmaster) and have been slowly widdling it down to proper size. It got sensitive when the speed picked up with the M545... You know, working the setup out is the real kick for me!

The sponsons are pretty radical, most wouldn't think the numbers would work, but they do! The left sponson is 1/8" lower than the right. The angle on the right is 2.5 degrees and it's 1.3 degrees on the left. This forms a solid outside runner, allows the right sponson to run with less drag. The right sponson is 0.20" deeper than stock. This opens the air trap up behind the sponsons, spilling the air this hull likes to accumulate stock.

There is also a very aerodynamic wing, or canard, on the front. It is set to divert some air from the bottom, to up over the top. But the real cool stuff is the reverse wing design used on it. When the nose comes up from wind or waves, the reverse wing gets more laminar air flow over it, causing the negative lift to grow and put the boat back on the water. You can actually see it working! So, no air dams or strakes are used.

I'll get a better video hopefully soon. My wife, as great a love she is, has no videographer talents! Her videos can give you motion sickness, LOL!

[CraigP]

The video is great of your boat! It's getting at it. No porpoising, but some sponson dancing. Got a 4060 in there, eh? Do you think I'm on track with a 4050? I would rather spin the prop slower and use a bigger prop, the boat seems to like that better than high rpm.

[properchopper]

The video is great of your boat! It's getting at it. No porpoising, but some sponson dancing. Got a 4060 in there, eh? Do you think I'm on track with a 4050? I would rather spin the prop slower and use a bigger prop, the boat seems to like that better than high rpm.

Given that my specific frame of reference in Sport Hydros are those in P Class [4s 10Kmah 34" length limit] my experience has evidenced that the popular three P-Sport Hydros { PT Stealth, Whiplash, FE 30 + some ML's I'm not too familiar with) all are around 30" and mostly run what started as Neu 2200KV 1Y's which have evolved into Castle/Neu's, Leo 4074's and TP 4060's. Easy 60+mph rigs ( My Neu 2200 1Y FE30 maidened at 68.xx mph with a M445). I'd consider the TP Power 4060 as a good choice for the DF34 - It'll get high 50's / likely more. Probably stay out of the danger handling zone. The 4070 in mine is overkill.

[rol243]

one of the quickest sport hydros i have seem running was a Whiplash- fe powered by a 1512 - 2650 kv on 4 s. he did try a 1515-2200kv but speed was not there.

[CraigP]

All those hulls are wicked fast... I built the DF because I wanted a tribute boat to my brother's GP55. Those fast racing hulls have exaggerated sponson widths in ratio to the stern. They are also long waisted, so they don't look like full sized boats. I think the DF is too long and heavy to win... But still, I'm getting the itch to race. I might build one of those hulls just to race it, and leave the Littl' GP55 looking good! You guys gave me some great intel, thanks!

[R2315]

It's looking awesome Craig! and very nice work on the sponsons, mean looking indeed!

[properchopper]

All those hulls are wicked fast... I built the DF because I wanted a tribute boat to my brother's GP55. Those fast racing hulls have exaggerated sponson widths in ratio to the stern. They are also long waisted, so they don't look like full sized boats. I think the DF is too long and heavy to win... But still, I'm getting the itch to race. I might build one of those hulls just to race it, and leave the Littl' GP55 looking good! You guys gave me some great intel, thanks!

Craig,

In NAMBA the P-Sport Hydro class rules don't specify that the boats must resemble real Hydros, only that they conform to certain dimensional/proportional considerations.

Here's some NAMBA P-Sport Hydros [FE30, Whiplash, PT Stealth& a Randy Naylor design] slugging it out in Az.
https://www.youtube.com/watch?v=giN0xQeA8RE




The 1/10 Scale Vintage, 1/10 Scale Modern and 1/8 scale class have to look like an existing full size / actually raced boat including engines and drivers..

[rol243]

Scale Class . those sport hydros were going along very nice.

[CraigP]

You guys mis read what I meant... I don't want to race Scale, just build a boat that I could make look like my brother's boat. I built the boat to do R&D on LiPo batteries and their possible commercial use in industrial designs. But I might be getting the racing itch! I was watching some FE30 boats on Utube, Tony, I think one of the video's was yours. They do have sponson walk and porpoising in the turns. My DF doesn't do that, but I currently lose more speed in the turns. But if it's a rough and windy day, I'm thinking I might hold my own! My modified DF will run some ugly water well...

[rol243]

not that i have these hulls but what i have seen in fe-30 size sport hydros , the quickest and best handling hulls have been either the ML Boatworks or the Whiplash. if you can buy or build one of these hulls i am sure you will be very impressed in what they do.

[properchopper]

You guys mis read what I meant... I don't want to race Scale, just build a boat that I could make look like my brother's boat. I built the boat to do R&D on LiPo batteries and their possible commercial use in industrial designs. But I might be getting the racing itch! I was watching some FE30 boats on Utube, Tony, I think one of the video's was yours. They do have sponson walk and porpoising in the turns. My DF doesn't do that, but I currently lose more speed in the turns. But if it's a rough and windy day, I'm thinking I might hold my own! My modified DF will run some ugly water well...

Since you've concluded and posted that FE30's "have sponson walk and porposing in the turns" I'd like some equal air time. To begin with, I participated in the design of the FE30, tested prototypes until final design approval, singlehanderdly rolled them out to market, race-rigged more of them than anyone on Earth, and have raced both of mine from the very start (and my P-Ltd Sport, the very first production example is still racing and winning)with much success, + watched as many FE30's won countless races and Nationals. SO:

They DO NOT have any inherent design characteristic that causes sponson dance in the turns. NONE. In a turn the outside sponson lifts from prop torque while the inside turn fin acts to to pull the inside sponson up / the outside sponson downand a tug of war is initiated as the sponson rear tips tap-dance over the racewater. If you're properly flying the hull this is what happens. Check out 36+ seconds in this vid &
you might want to plug your ears :ohmy:
https://www.youtube.com/watch?v=jC6I_ad8Isw
(No park Rangers were injured during the making of this video)

Not sure what you mean by porposing, but if prop lift, strut depth and angle, and fore-aft CG aren't adjusted to keep the a** from hopping, once maximum lift angle is achieved, gravity and the slowing from the front sponson area being wetted and slowing the boat down, the a** will hop. This can be tuned out but in typical racewater it's not a huge issue.

The real test for your DF34 is to see what happens once sped up to P-Sport levels (60 to 70 mph). At 1/2 throttle my un-sponson modded DF34 doesn't exhibit any real problems either. Unleashed is a different story. Either way a DF34 rigged for P-Sport Hydro would be liked racing a Cadillac Escalade against a Formula 1 racecar given the competition from the current class winners.

[CraigP]

Points well taken... No racing for the Littl' GP55! Didn't mean to get you riled up.. I think I said those are mean boats. You gotta race on the edge, to win..

[Beaux]

Did you reinforce the hull anywhere? Those sponsons are killer love the metal work.

[CraigP]

The sponsons are working great, the boat is very stable all around the course in the mid 50’s. I think it will be the same in the mid 60’s as soon as my driving skills get to that level. I crashed the boat right after final paint early in the summer, driving over my head.

I did add two, 0.031” 6061-T6 aluminum plates to the bottom. The Vortex stock has a lot of hull flex in it, because it has no frames. The aluminum on the sponsons shored those up, but you could still grab the sponson tips and move them up and down, or side to side flex. The aluminum plate under the two, 4s battery boxes fixed that. Then I noticed a resonance sound out on the water at full throttle. I found the hull was vibrating right under the motor, actually making the hull bottom sing with the driveline vibration! So I cut a T-plate and mounted it under the ESC, extending down to the stuffing tube support. Noise gone! This plate is very light, the first weighed 3.7g and the second was 4.1g, so virtually no penalty for the added support. The first pic the boat ready to run...

[Fluid]

To reinforce Tony’s comments on the FE-30, mine was one of the first few sold and was arguably the fastest P-Limited boat in Texas. I sold it to a well known racer, who put a full P setup in it and set the fastest-ever race heat record with it at the 2016 Nationals. Properly set up it is the proven class leader.

That said, my unmodified DF Vortex 34 was a bit better in really rough water, for two reasons. First it is a much bigger boat which gives it some stability advantage, and second, speeds are lower in the rough. On smooth fast water the FE-30 wins. I don’t know what would happen with a modified DF Vortex though, never modified mine past air dams and a deep strut (both helped).


.

[CraigP]

There are two mods that I think are helping the most: 1) the angle changes on the sponson ride pads (btw, certainly does not need to be aluminum. I’m just comfortable working with sheet material) and 2) the front wing/canard. This wing has proven more effective than air dams, providing much more range (nose up and down) than air dams would. The angle of attack on the wing firstly directs more air over the top of the boat, in a smooth laminar fashion, so there’s less turbulence created. The bottom of the wing is an engineered reverse wing, which gets stronger as the nose comes up more. When the boat gets to about 15 degrees of nose lift, the wing literally “flys” it back down. It’s a trip to see! Another feature, I guess 3) is I made the sponsons deeper by adding the laminated wooden rails, as pictured. This increases the amount of air that can escape out the sides of the air traps by increasing the open area.

Here’s the pity of it all... I still can’t drive the boat to the speed it’s capable. I really do believe it will run with the FE30 on smooth water, but I can’t keep up with the boat yet at anything over 60mph. I’m hoping to have Oscar Love test drive it at some point so I can see where the performance line is. As Jay mentions, it is a good rough water boat because of size. But it’s a real flexy flier, just a bunch of hull flex at speed well above it’s pay grade!

[Beaux]

We had the same idea about the front wing, it needs one. That's what my next build will be.

[CraigP]

I have a 32” Skater Cat that I’m going to try a wing on. Man are those boats snappy on the flips!

[CraigP]

The boat still set up to run 8s, but it’s now ready to run the two, 4s packs in series or parallel. The 8s setup consists of a Leopard 4082, 1250kv motor which runs about 35K rpms on the water. This is the motor I crashed it on... The slow motor was a Leopard 4072 1050kv, which is quite a bit slower. I’m going to start running this faster motor with the smallest prop in my box, a Grim Racer 42X55mm 2-blade. My biggest blade is an X448, which will run it well over 70. That’s on the back burner...

The 4s setup consists of a TP4050, 2310kv motor. I bought the Turnigy 4s, 5000mah from Truckpull here on the site. I think he used them in P Sport. I’ll run a parallel setup for 10,000mah. This setup spins a bit slower than the 8s setup, so I should be getting into bigger props more easier on it.

The M445 has been a very good prop! With little motor, I ran a M545 and a M645. The 645 started getting the boat out ahead of me. My wife, using a radar gun I have, had it at 62mph, which is where I’ve been stuck at in my driving capabilities. I’m having fun getting better, would like to be comfortably running faster sooner rather than later. It makes you really respect these guys that handle these boats racing against each at such high speeds! Cudos to all of you guys, you give me a lofty goal to get to!

A special shoutout to Oscar Love, who traveled to Tulsa to run with some of his mates and me. Oscar showed me where I need to get to... I really appreciated that Oscar!

[rol243]

I have done some tests in my small test lake with a T.P.4050-2310 KV and in the same hull a Castle-Nue 1415-2400 KV both using the same prop ABC H7 stock and the T.P. Motor is faster for sure. so it must be the larger diameter motor can that makes this motor the quicker of the two. the T.P. Motors seem to be a good unit.

[oscarel]

The boat still set up to run 8s, but it’s now ready to run the two, 4s packs in series or parallel. The 8s setup consists of a Leopard 4082, 1250kv motor which runs about 35K rpms on the water. This is the motor I crashed it on... The slow motor was a Leopard 4072 1050kv, which is quite a bit slower. I’m going to start running this faster motor with the smallest prop in my box, a Grim Racer 42X55mm 2-blade. My biggest blade is an X448, which will run it well over 70. That’s on the back burner...

The 4s setup consists of a TP4050, 2310kv motor. I bought the Turnigy 4s, 5000mah from Truckpull here on the site. I think he used them in P Sport. I’ll run a parallel setup for 10,000mah. This setup spins a bit slower than the 8s setup, so I should be getting into bigger props more easier on it.

The M445 has been a very good prop! With little motor, I ran a M545 and a M645. The 645 started getting the boat out ahead of me. My wife, using a radar gun I have, had it at 62mph, which is where I’ve been stuck at in my driving capabilities. I’m having fun getting better, would like to be comfortably running faster sooner rather than later. It makes you really respect these guys that handle these boats racing against each at such high speeds! Cudos to all of you guys, you give me a lofty goal to get to!

A special shoutout to Oscar Love, who traveled to Tulsa to run with some of his mates and me. Oscar showed me where I need to get to... I really appreciated that Oscar!


Oh now stop it!!! I had a great time up there with you guys. I have 1 more trip planned for this race season then I'll try and make my way back up there before it gets too cold.

Boat is looking good too, keep up the mods and testing.

[Beaux]

After seeing your metal work inside and out, I kind of figured you were pretty comfortable there. Mine is gonna have to be good old fiberglass.

[properchopper]

"But it’s a real flexy flier, just a bunch of hull flex at speed well above it’s pay grade!"

Nonsense. Curious how this was observed/measured at "speeds well above its pay grade"

My V34, Howards and Jays have had issues, but never has hull flex been one of them based on extended off-forum conversations we've had regarding tuning for max speed. Out of the box the initial impression of mine was that it's as rigid as if it was made of concrete.

The hull packs air . Putting wings on won't stop the tendency to lift , only fight against it in to attempt top cancel it. Makes sense to me to use an air dam to reduce/control it before it ever becomes a problem rather than letting it happen, then counteracting it. Most FE wing additions have proven futile at best, historically.

Sounds cool on paper 'tho :olleyes:
2) the front wing/canard. This wing has proven more effective than air dams, providing much more range (nose up and down) than air dams would. The angle of attack on the wing firstly directs more air over the top of the boat, in a smooth laminar fashion, so there’s less turbulence created. The bottom of the wing is an engineered reverse wing, which gets stronger as the nose comes up more. When the boat gets to about 15 degrees of nose lift, the wing literally “flys” it back down. It’s a trip to see! Another feature, I guess "

My amp goes to eleven..............

[CraigP]

Not a fan Tony, I get it... As far as flex is concerned, I fixtured one side to the table and easily displaced the free sponson tip up and down nearly 5/16” in each direction. I only had about 1/8” deflection after the bolster plate was put in. You seem to have a lot of emotion tied up in this. For me, it’s just about optimizing what I have in front of me, solving problems as they come to my attention. Fortunately, your approval isn’t necessary... You’re a better driver than me by a long shot, but I can set up a hull. Maybe your hull was laid up with more glass?

[CraigP]

To respond to Tony’s comments about my front wing, the wing is not on paper anymore. It is on the boat, doing what it was designed to do! So please, go roll your eyes on some one else’s thread. I have nothing to prove to you and I don’t seek your approval. I know you can be helpful, but in this case, you’re anything but that. I, and I’m sure others, found nothing useful in your comments. Just go play with your own toy boats and let me be.

[CraigP]

Ran the hydro today, terrible! I thought for sure the weight distribution had been disturbed after putting in the new battery boxes and running the two, 4s batts instead of the four, 2s batts I had before. I checked the CG most diligently with the old and new batts. Looks like they are still within 0.020” of each other, that’s not the problem. I did find my turn fin setting was way off, sucking the right side down hard. The strut was off too, about 0.100” higher. The boat was really picking up the left side and porpoising very badly under hard acceleration going straight. Turns still looked pretty decent, just the right side a bit too glued down. The settings are touchy! But I did a lousy job re-setting the boat after having it apart putting in the new parts... you learn something new every time you run one of these things.. I was concentrating on the ride characteristics and Boom, it’s down to the pin in a flash! Sure could use someone to video so I can keep my mind on driving it. Feels like I’m trying to text and drive, lol!

[rol243]

Craig, is the turn fin a standard one that comes with this hull ? looks to have alot of hook in it. i did a fare bit of testing different fins on one of my gas powered sport hydros and did find the fins with too much hook was certainly very good in the turns but funny things occured in the straights making driving abit left and right. maybe with your hull a fin with a bend could work better than a hooked fin., worth a test anyway. also could you try placing the battery packs on the left side at cog to see if this helps to keep the left [ port ] side down. hey buy a cheap go-pro type camera and wear it on your head , works really well if you want to film on your own.

[CraigP]

Man, great idea on the go pro! Will do that! On the turn fin, the hull was a bare hull, so no “stock” fin was with it. It is a curved fin that was made for 48” hull that I cut down. I do have a bent fin that I ran before this with good results. You’re right, I need to compare the two. Running today, so I’ll do that.

It is extremely sensitive to course changes going straight. There was a sweet spot where it ran very well, but now that I think about it, I think it’s always been sensitive on the straights.

I can’t move the other battery over, there’s no room under the deck... That’s what made the four, 2s packs rather special for the weight distribution. But the CG checks very nearly dead on between the two battery setups. Last night I thought about having a 2s pack with me at the pond I could just set with Velcro on the left side if I’m still having perceived weight issues. Thanks for the great advice!

[rol243]

As mentioned i had a few fins to test on the gas hydro and some of the fins made the boat very very sensitive just in the straights , it was like the boat just wanted to wonder off course on its own and when radio input was given for correction only the slightest amount of rudder control was used. the hull was almost un driveable until i ended up buying a Titanium cnc fin as used on most Whiplash sport hydros., was a dream to drive then. so play with the turn fins until you find the right one and i am sure your hull will go really well. make sure c.o.g. is correct too.

[CraigP]

I’m going to just swap over to my bent fin... getting ready to run it now. CG is correct, thanks for the input! Wish me luck!

[rol243]

OK let us know results.

[CraigP]

Just got back, like a new boat! Very high winds, average 7-10mph, gusting 15-28. I almost decided it was too much. But felt that it would be a perfect time to check out adverse conditions. Man, I wish I had that GoPro! There wasn’t white caps, but consistent 2-4” rollers. Boat handled it great! The bent fin is definitely better than curved. Dropping the strut 0.100” and making sure it’s at zero degrees just took all the porpoising out. The boat hit rollers 3-4 times, each time coming completely out of the water, but staying absolutely parallel to the water. It just settled right back in. It even jumped in the corner and flew the same way. No doubt CG is right. The bent fin also is about 5/8” further back than the curved fin, just because of mounting hole differences. Right sponson ran more free and only noted sponson walking while going over some pretty high rollers. I checked CG before running at it was right on the leading edge of the turn fin. When I got back, I noted strut, rudder and turn fin setup in my notebook. I also ran a M445, has been my best prop. I had a small, 42X55 2-blade Grim Racer with about 17 degrees of rake on it yesterday. This boat just doesn’t like high rake props. One other note, it was so rough, the ESC Mount broke loose! Didn’t cause an issue, but certainly a testament to rough water. Thanks Ronald for some excellent pointers!

[CraigP]

Here’s a pic of my brother’s GP boat in San Diego. It’s wave jumping too... My boat looked like that, but much higher out of the water. I love seeing hydros fly!

[CraigP]

For you hydro lovers, here’s a pic of arguably the most dominant Unlimited in history, the Bardahl Green Dragon! This is what my little hydro looked like, rudder completely out, flying parallel to the water. I’m a happy guy tonight!

[rol243]

certainly a great old hydro there [ miss bardahl ] used to be avaialble in kit form and maybe you can still get them other than planes only. hope your strut isn,t set at that same angle in pic Craig. lol

[WestJL21]

Dilly, Dilly CraigP ! :tiphat:

[CraigP]

certainly a great old hydro there [ miss bardahl ] used to be avaialble in kit form and maybe you can still get them other than planes only. hope your strut isn,t set at that same angle in pic Craig. lol

You know they tried for years to come up with a universal joint that could take the shaft HP, never did it. The shaft angle has always been a design flaw that begets many different work arounds. We are lucky to set it neutral!

I’ve thought about building the ‘66 Bardahl Ron Jones cab-over, that killed Ronny Munson on that fateful day in DC. I was there... But shovel noses are a real design compromise. If I did build one, it would probably be my Dad’s Parco O-Ring Miss, the Karelsen hull..

[CraigP]

Dilly, Dilly CraigP ! :tiphat:

Not sure what this means, I must have gotten off the bus!

[Beaux]

Hey Craig, Beaux here do you have any pictures of your strut and rudder set up. I just ordered mine and was curious . Thanks.

[CraigP]

Here’s a couple of shots. This is all Speedmaster hardware. It’s the larger hardware with the rudder cut down. I used the larger strut to have enough meat to put in a rear lip seal, to stop grease loss and prevent water from breaking down the grease.

[rol243]

where the shaft tube log joins up with the strut, use some heat shrink tube , this will keep water out and not create any drag as you have now CraigP.

[CraigP]

Yes, it’s an old pic, someone posted that recommendation a while ago and it’s had heat shrink with silicone underneath since August. The stuffing tube has too small a bend radius and was replaced in the summer. That was another good piece of advice I received. I’ve learned much here!

[srislash]

What are all the holes in the strut upright Craig?

[Beaux]

Thanks Craig.

[CraigP]

What are all the holes in the strut upright Craig?

They are for the seal retainer plate. The one closest to the strut hole is a broken tap! The upper two are threaded holes. I do it differently now, I use a retainer clip like a Cir-Clip.

[srislash]

Slick!!! I like it!!

[CraigP]

I ran the boat 15 times when first installed then took the shaft out, the grease was fine. Slight discoloration due to the copper fines mixing in. Re-greased and ran another 15, same thing. I’m now on run 22 with the third change. It’s easy to put too much in, and it will leak out at the coupling. I use a silicone sleeve there, like many others. After a run or two, it will stop that and maintain the grease. I have a procedure for my boats now, they all have sealed struts. The Hydro, Mono and Cat have different grease loads.... it’s a possibility I can run the whole season. I’m going to run 30 times then check it.. Better to sneak up on it then assume!

[CraigP]

Setting up to run today... I think I stepped backwards converting to two, 4s batteries. It is flying more in front and will pick up some pretty vicious sponson walking in rough water and wind. It needs more weight up front. So this month I’m going to convert it back to four, 2s cells so I can get the batteries more forward that I can the 4s batts. Dropping the strut some did not solve the problem, and I think that’s a poor way to fix another problem.

Tony Hellar built this hull and I think he said he got his batts in each sponson, running lengthwise. For the life of me I can’t figure out how he did that! I couldn’t get the Turnigy batts in there. That’s the best place weight wise which is probably why his boat ran very well.

I’m also running the slower 1050kv motor. At 1250, the hull was just too fast heading into corners and I had to back off. I’ve ended up running very small props, X442 and such. So I want to turn it slower and get back to larger wheels. I was showing the low-60’s on 1050 motor and M445 and Prather B220 earlier in the summer. So I think that’s the better route to faster speeds. I’m driving better now, it’s been an experience!

I want to thank all for the support and good advice through this. I’ve really enjoyed the build and learning process.

[srislash]

I’m going to give a lower rpm a shot on my big hydro that is upcoming. I think there could be runtime to gain too out of the HV and lower RPM method