Whiplash P Sport Hydro Build

[jfrancisco892]

I'm going to start on my whiplash this weekend. I am gonna do a video series instead of taking pictures and typing long descriptions describing everything. Just wanted to see if anyone would be interested if I took the time to do this.

[JrValente]

I am in. :thumbup1:

[longballlumber]

I might just keep an eye on this one! :wink:

Later,
Mike

[HydroMike]

I'm in

[detox]

Medium CA glue and accelerator will speed up the build...especially when sheeting tips and sides of sponsons. Drip applicator works best when applying the accelerator.

[Rumdog]

In!

[jfrancisco892]

Part 1


http://www.youtube.com/watch?v=yLEDa7hd7Mc

[detox]

Nice video. I have ran the .187 cable with and without liner. I like using the 1/4 stuffing tube with no liner best.

[jfrancisco892]

Nice video. I have ran the .187 cable with and without liner. I like using the 1/4 stuffing tube with no liner best.

Thanks for the input!

[longballlumber]

Nice Job!

I think your right that 3/16 cable is the way to go. However, I would advise against the Teflon tubing in the stuffing. I am not convinced it offers any positive other than more parts. I would stick with 9/32" sleeve epoxied and glassed into the hull and the 1/4" as the stuffing tube (no liner). They have been using this system for MANY years. It's bullet proof. Just my 2 pennies.

Later,
Mike

[jfrancisco892]

Nice Job!

I think your right that 3/16 cable is the way to go. However, I would advise against the Teflon tubing in the stuffing. I am not convinced it offers any positive other than more parts. I would stick with 9/32" sleeve epoxied and glassed into the hull and the 1/4" as the stuffing tube (no liner). They have been using this system for MANY years. It's bullet proof. Just my 2 pennies.

Later,
Mike

I suppose we will have to agree to disagree. I talked with pete and he had some good tips on how to secure the liner so that it doesn't spin up into the collet. I also don't like the idea of the flex cable having direct contact with the brass tube. It seems like a lot more friction that is averted when a teflon liner is used.

Just as an update, I got the strut, rudder, and motor mounted this weekend. I didn't have time to make another video but I will do one in the near future. I am going to have some machining done on the motor mount to take off 1/8" off the bottom to lower the cog of the motor. After that I'll do a layout of the boat to determine how I am going to bend and mount the stuffing tube. After much debating I am going to do a "J" bend as opposed to an "S" bend. This is a bigger debate on this forum than pro choice or pro life, but that is what I am going to go with. I can only work on the boat on certain weekends because I work on it at my parent's house and I work away from home, so I probably won't get any more stuff done on it until the 14th.

[longballlumber]

No worries,

That what makes this hobby great. Do what you think is right. There are many ways to "skin a cat"!

Later,
Mike

[jfrancisco892]

No worries,

That what makes this hobby great. Do what you think is right. There are many ways to "skin a cat"!

Later,
Mike

Sounds good.

[jfrancisco892]

http://www.youtube.com/watch?v=cLBG4_H76fU

Part 2 Finally.

[detox]

S bend is doable, but more work and unecessary. Just use single bend with minimum angle with good adjustabilty on the stuffing tube. I am sure you are mounting ESC next to stuffing tube. That is where i mounted (loosely) my Hydra 240. What prop are you starting out with? You may need a little tongue on prop to get that heavier P sport on plane quickly. Slight Cup on prop tips will get her going fast. I also raised and widened my ridepads because of heavier 4s2p weight.

[jfrancisco892]

I am going to mount the esc between the batteries and the motor..it just fits. I am going to start with a grimracer 42x55. Thanks for your input.

[Tunda]

Cool vid Bro..........

[jfrancisco892]

Cool vid Bro..........

Thanks!

[Shooter]

I can't believe it took me this long to find this thread! Nice job! I love the video idea!

[jfrancisco892]

I can't believe it took me this long to find this thread! Nice job! I love the video idea!

Thanks man. I didn't want to deal with the typing out of all the descriptions and posting all the pics. I thought this was easier and something a little different.

[Shooter]

I suppose we will have to agree to disagree. I talked with pete and he had some good tips on how to secure the liner so that it doesn't spin up into the collet. I also don't like the idea of the flex cable having direct contact with the brass tube. It seems like a lot more friction that is averted when a teflon liner is used.

Mike's boat beats my boat 3 ways to Sunday, yet you take my advice....I love you man!!!

[jfrancisco892]

Mike's boat beats my boat 3 ways to Sunday, yet you take my advice....I love you man!!!

You took some bad advice from me. I feel the deed has to be repaid. Jk lol. But on mike's stealth he runs a Teflon liner.

[longballlumber]

You guys crack me up LOL

I will not be running Teflon in any of my NEW builds. I don't run Teflon in my Q sport hydro AND it has an S bend. No one has been able to convince me that Teflon has less friction (AKA faster) than a non-lined stuffing tube (assuming everything else is equal).

About the S vs. the J bend... Ask yourself this, in conditions that have a very long drive shaft or "prop shaft" (think heavy capacity, long wheelbase trucks) nearly all of them have a "shaft" carrier bearing at some point along the length of the drive shaft. Why would they do that? I am thinking to support the shaft and minimizing flexing (shaft whip)?

Our flex shafts are the same only worse because they are more flexible meaning they need to be supported; hence an “S” bend where it is supported better than a “J” bend.

I will also say there are many boat out there that are very fast with a “J” bend and Teflon… That is what makes this hobby so great! :thumbup1:

Later,
Mike

[jfrancisco892]

You guys crack me up LOL

I will not be running Teflon in any of my NEW builds. I don't run Teflon in my Q sport hydro AND it has an S bend. No one has been able to convince me that Teflon has less friction (AKA faster) than a non-lined stuffing tube (assuming everything else is equal).

About the S vs. the J bend... Ask yourself this, in conditions that have a very long drive shaft or "prop shaft" (think heavy capacity, long wheelbase trucks) nearly all of them have a "shaft" carrier bearing at some point along the length of the drive shaft. Why would they do that? I am thinking to support the shaft and minimizing flexing (shaft whip)?

Our flex shafts are the same only worse because they are more flexible meaning they need to be supported; hence an “S” bend where it is supported better than a “J” bend.

I will also say there are many boat out there that are very fast with a “J” bend and Teflon… That is what makes this hobby so great! :thumbup1:

Later,
Mike

Hope we are not cracking you up in a bad way. Your points definitely do have some validity to them. I was thinking about the long shaft needing support and I though of a driveshaft and I feel it resembles more of a J bend than anything but everyone has a different opinion. Just out of curiousity did you ever think that an S bend may cause more resistance through its support than a J bend. We could talk about this all day lol. When it boils down to it you have been in the hobby far longer than I have and know a lot more about it than I do. And your boats will kick my butt lol. But anyway, you're probably the person to trust in this situation. Just how I look at the flex shaft scenario.

[longballlumber]

No worries here jimmy... Regardless of J's, S's, Teflon, or no Teflon it's all good. The ingenuity is the part I like best about this hobby. As much as we think we understand the variables, there are plenty more to follow making us scratch our heads... Just ask Terry about tail feathers on the back of a hydro, and I will be he will tell you how much he under estimated the impact of the handling on his boat. No matter our experience level we all learn new stuff all the time.

Later,
Mike

[jfrancisco892]

No worries here jimmy... Regardless of J's, S's, Teflon, or no Teflon it's all good. The ingenuity is the part I like best about this hobby. As much as we think we understand the variables, there are plenty more to follow making us scratch our heads... Just ask Terry about tail feathers on the back of a hydro, and I will be he will tell you how much he under estimated the impact of the handling on his boat. No matter our experience level we all learn new stuff all the time.

Later,
Mike

Let's stop bs'ing and get ready to race! lol

[Shooter]

But bs'ing is the best thing about this forum!!

Hey, I just watched the end of the 2nd vid. I can't believe there was a 0.030" difference between the mount spacing....and they were on an angle???? That looks like a south river mount. I've never had any problems with them. Jim's stuff is always top notch!!! You should contact him and let him know.

As for teflon, I've never noticed a difference between 'with' or 'without', myself. I still run with it though. I do favor teflon with the 0.187 for sure because the recommended brass is a very loose fit....I never liked that.

Mike - That's a great point regarding shaft support. It would seem that the cable would 'find support' and rub along the sidewall somewhere, even if the stuffing tube was straight, just due to the torque in the cable. Your S provides more support...maybe even the 'natural' form of the cable while in operation. The question might be how many of those 'support' locations do you want to force? Too little and you get the whip action and instability. To many and you increase friction/drag/heat. Interesting stuff....

[jfrancisco892]

I'll let him know about the mount. Gonna be a mad thrash on Wednesday to try to get her ready for open water on Thursday. Still need to get the esc though. Hopefully it comes by Wednesday. I am almost convinced that when done correctly it doesn't matter if you do a j or s bend or Teflon or no Teflon. I've seen fast boats with all of those different setups. Perhaps we are thinking about it more than we should.

Anyway I'm pumped for this weekend. Should be a lot of fun just pray the weather cooperates.

[madmikepags]

The S bend has been proven time and time again to be the superior way to go, oh or wait was it the J??? crap I cant remember, I have probably equal amounts of boats with each!!! But I did have a big cat once that had a J bend setup, and it kept breaking flex cables, I changed the motor mount put a slight s in and it never broke a cable again. I am also moving away from teflon, My LSO has been tearing through motors, I couldn't figure out why? It's probably the lightest LSO on the planet and it's under propped but there's always smoke inside when I run it but not burnt electric smoke. The teflon liner was spinning inside the brass tube and causing binding the tube was so hot the brass was untouchable. Removed the teflon the boat is faster than ever and no smokey!!!!!!!

[longballlumber]

The teflon liner was spinning inside the brass tube and causing binding the tube was so hot the brass was untouchable. Removed the teflon the boat is faster than ever and no smokey!!!!!!!

THAT is exactly why, I won't be using Teflon in any of my new builds.

Later,
Mike

[Shooter]

Yep....definitely a problem if the teflon tubing spins. I roughen mine up with a coarse file for the first 1" length. Rough to the point that the outside looks like it's growing hairs. Then, a few drops of CA, slide her in, and no problems. However, I can undersand the argument of 'one more thing to go wrong' though.

Hey MadMike - How light is your LSH? Mine is under 5lb with 5000mah.

Hey Regular Mike - Let me know when you want those decals....send me the dimensions!! I'll shoot you a text as well!

[Hydrozz]

I've used with and without teflon. Never had a problem with teflon. I too rough it up and lightly glue it in place. The extra bend in stuffing tube might help with the spinning. To me, spinning a shaft in a tube, lubed up. With teflon there seems to me to be a little more friction. Could depend on your bends. When I do build one without a linning. I Lap my cable in the tube. Does seem to help in a more free spinning cable. Just my 2 cents.

[jfrancisco892]

It's been settled. S bend and no Teflon it is.

[detox]

Thread is dead. I would like to see this S bend.

[jfrancisco892]

Lol. I'll get to it. Plan is to get it running by next Sunday.

[mojoracer]

You guys crack me up LOL

I will not be running Teflon in any of my NEW builds. I don't run Teflon in my Q sport hydro AND it has an S bend. No one has been able to convince me that Teflon has less friction (AKA faster) than a non-lined stuffing tube (assuming everything else is equal).

About the S vs. the J bend... Ask yourself this, in conditions that have a very long drive shaft or "prop shaft" (think heavy capacity, long wheelbase trucks) nearly all of them have a "shaft" carrier bearing at some point along the length of the drive shaft. Why would they do that? I am thinking to support the shaft and minimizing flexing (shaft whip)?

Our flex shafts are the same only worse because they are more flexible meaning they need to be supported; hence an “S” bend where it is supported better than a “J” bend.

I will also say there are many boat out there that are very fast with a “J” bend and Teflon… That is what makes this hobby so great! :thumbup1:

Later,
Mike

Mike you are on the right track about shaft "whipping". Long wheel base trucks have multiple piece drive lines is to increase the 1st bending mode of the drive line. 1 long tube has such a low frequency 1st bending mode, that the vehicle critical cut-off speed would be way to low for highway use. This is why many light duty pick-up trucks with 1 piece shafts are speed governed to not much more than 90 mph . The same truck with a 2 piece drive line, or a huge diameter 1 piece shaft could probably run up to 120 MPH or more. Most trucks over 130" wheelbase will use 2 piece drive shafts with center bearings. I have wondered what that flex cable could be doing inside of the tube at certain speeds...

[Shooter]

Jimmy - You gonna get this thing done or what???

Interesting stuff Bob. I remember reading that aluminum (less mass) driveshafts were a huge upgrade to improve the max rpm prior to resonance. Kind of supports the use of a wire drive??

[jfrancisco892]

Jimmy - You gonna get this thing done or what???




If there was a field of p sports ready to race I would have more motivation to get it done. It will get done. I'm sorry it’s taking so long, I have been to Norwalk for the NHRA event for 4 days, Eldora Speedway for the kings royal, the gold cup on the Sunday after the kings royal on Saturday, Cedar Point last weekend, and spent some time with family this past weekend. Also taking a college class right now and working full time lol. I want to finish it with my dad as he is one of the most talented individuals I know when it comes to building and fabricating just about anything. He has been working Saturdays every week, so I am waiting for him to have some time when we can enjoy putting it together RIGHT. It is almost done I just don't want to rush it if I do not have to.

I'm just rambling but it sounds like p sport is starting to get some interest. It should be a fun class with some fast boats. It's gonna be competitive if I were to guess, as everyone in the club is extremely knowledgeable about building boats and getting them running well. Looking forward to the next club race. My last day before I can legally consume ADULT beverages :smile:

[detox]

Prebend and trial fit "S" stuffing tube before gluing into place. I would not set strut too deep while doing this. Allow for some strut height adjustment. My strut height is about 5/8" from bottom of stern on setup board.

[jfrancisco892]

Prebend and trial fit "S" stuffing tube before gluing into place. I would not set strut too deep while doing this. Allow for some strut height adjustment. My strut height is about 5/8" from bottom of stern on setup board.

So 5/8 from the bottom of the hull to the bottom of the strut?

[detox]

So 5/8 from the bottom of the hull to the bottom of the strut?

Yes. Download Aquacrafts UL-1 user manual from their web site. Lots of good Hydro info there.

You will also have to anneal (soften brass) your 1/4" stuffing tube. Heat areas to be bent to Cherry Red (or just before turning cherry red) using propane torch then let cool. This will make bending LOTS easier.

[jaike5]

Put appropriate size cable inside the tube when bending , helps prevent crimping the tube.
cheers, Jay.

[tjcast]

Current Whip has .187 cable, no Teflon, 1/4" stuffing tube. Currently has J bend but unless greased every heat will occasionally have some 'vibration' noise while running. Next build will have an S bend.

[Shooter]

Tom's boat absolutely zings!!!

[tjcast]

Jimmy's run against my Whip a few times in the P- Limited setup so he knows what it can do. Too bad he won't be at practice so he can see the new and improved P-Sport Whip !

[jfrancisco892]

Jimmy's run against my Whip a few times in the P- Limited setup so he knows what it can do. Too bad he won't be at practice so he can see the new and improved P-Sport Whip !

Is it done?

[tjcast]

105586105587105588105589
Is it done?

Needs paint and testing!

[jfrancisco892]

Looking good! 1515 1y?

[tjcast]

No . . . . just a little bit bigger :wink:

[Mike Caruso]

No worries here jimmy... Regardless of J's, S's, Teflon, or no Teflon it's all good. The ingenuity is the part I like best about this hobby. As much as we think we understand the variables, there are plenty more to follow making us scratch our heads... Just ask Terry about tail feathers on the back of a hydro, and I will be he will tell you how much he under estimated the impact of the handling on his boat. No matter our experience level we all learn new stuff all the time.

Later,
Mike

2nd that Mike The ingenuity is the part I like best about this hobby.
Remember back in the 70's we ran a straight 3/16 harden drive shaft with needle bearings on each end of the stuffing box. Then one guy I don't remember who did some testing and we all added a middle needle bearing in the stuffing box tube, but 1/3 of the way down from either end. Seem to run smoother on the water than the bearing in the middle. Everyone thinking and sharing so no one else has to waste their money. Yes it is the best Hobby and friends for me too.
I ran an old Hughey 40 Hydro in the early 70's and yes it used an S -BEND NO TEFLON. Never wore through the tube and I ran the snot out of that thing LOL

[Shooter]

OK, I'm tired of getting beat by the guy with a spatula for a turn fin. I'm ordering one today!!!!

...and unlike Jimmy, I WILL be at practice to see the new and improved version!

[tjcast]

Lol! SPATULAS rule!!! :biggrin:

[tjcast]

Sadly I don't have enough left to make another turn fin and I can't find another spatula like that one !

[Doby]

So whats a decent P-sport prop?

[tjcast]

I guess that would depend upon what motor you are running. I'll probably start with a 447 and work my way up.

[Doby]

That's what I have right now....you guys just don't want to give away any secrets:spy::biggrin::spy:

[Shooter]

I ran a 642 on mine. Then opted for an M545 with speeds just a hair over 60mph. I bet people will be running 65 no problem by mid next year in this class. Gonna be fun!

[Doby]

Interesting......

[tjcast]

I guess that would depend upon what motor you are running. I'll probably start with a 447 and work my way up. Just like with any new build, start conservative to see how it runs, then experiment.

[mojoracer]

Tom is that a 30" hull?

[tjcast]

Yep. That's the Whiplash 20. With modifications.

[kevinpratt823]

I've tried a good handful of props in my whip(1515/1Y/4s2p)
H7 was good overall at 63 mph, the faster props lost a bit in other areas like coming out of the hole and walking, but H6 and H10 were both good, Oct 1650 got me 71 mph on both days I ran it so far. Haven't been back out again since. I liked all these better than M/X series personally.

[longballlumber]

Oh boy,

Now we are in trouble.... Looks very nice Tom. Jimmy where's your pictures?

Later,
Mike

[jfrancisco892]

Oh boy,

Now we are in trouble.... Looks very nice Tom. Jimmy where's your pictures?

Later,
Mike

Lol. I'll see what I can muster up before the last race of the year. Need to get my butt in gear and finish this thing. Too much other stuff going on but it's pretty close to being done.

[tjcast]

Not finished but ready for water on Wednesday!

[bozo586]

tom really looks good! maybe another winner. good luck-will be there wed.

[jfrancisco892]

Time to pull this thread from the dead as she's finally done. Not sure how many people will even see these posts with the e-mail notification issues on the forum but here goes.

Let's talk about the turn fin first. I'm not gonna take any credit on this as my dad did all of the work on it. All the machining on this was done on a cnc mill and my dad definitely knows what he is doing. The leading edge was done on a mill and each side of the fin was machined as opposed to most turn fins where it is only machined or filed on one side and makes the point by meeting the back side of the turn fin. The adjustment slot was also done on a machine and the radius matches the bracket perfectly to be adjustable. The turn fin mount was also drilled and tapped and a nyloc nut on the back of the mount for a lock nut. The bend on the fin was made by a die my dad made. It came out great and I have had good success with them with my UL-1 so I think it will be a slam dunk on this boat.
113962113963

[jfrancisco892]

For the stuffing tube I had my dad make me an alignment pin that is 3/16" on one side to go into the collet and the other side was machined to match the I.D of the 1/4" brass tube. Just a matter of test fitting, pulling it out and making slight adjustment until the shape is what you are looking for. There is a slight "S" bend in it even if it might not be apparent in the pictures. This was done intentionally as I wanted to provide support with as little resistance as possible. My dad had some epoxy that was water proof and it seemed to work out pretty well. Used some wax to keep the contained in the joint area, and used a grinder with a carbide burr to clean up some of the rough edges inside the boat and on the bottom as well.
113969113970

[jfrancisco892]

Man I don't know how I would do this boat stuff without my dad as he helps me out a ton. Here is another machining project I gave him which came out perfectly. To be able to get a wrench on the collet either the collet would have to be put on farther down the motor shaft or the screw heads needed to be recessed. I elected for the latter as this keeps as much of the collet as possible in contact with the motor shaft. The motor mount was counter bored to allow the heads of the screws to be perfectly flush with the face of the motor mount. The screws to be put in those holes were shortened the amount of the counter bore so both the top and bottom screws had the same amount of thread engagement in the motor itself. The bottom holes did not need to be machined as they do not impede the ability to get a wrench on the collet. One more thing to mention is that I did notice some runout on the collet, and was wondering if anyone else has had this issue with an octura collet or could recommend another brand to try before handing it over for my dad to machine it and put a bushing in it to get it to run true.
113971

[jfrancisco892]

For the flex cable I contemplated quite a bit as to whether to solder or not solder the end where the cut is made. I decided to go the Pete Luzenski method and chamfer the end of the flex cable without soldering it. I did not take any pictures of it, but I also had my dad do some machining on this as well to do the flat on the prop shaft for the set screw of the drive dog. The prop on there right now is a Grimracer L42x66. I feel this is a pretty conservative prop for the setup and a good place to start from. There is roughly a 3/16" gap between the drive dog and the strut bushing. I am not sure if everyone has the strut bushing protrude from the strut but I think it allows the bushing to free wheel or float more with no intrusion from spinning from contact with the strut.
113972

[jfrancisco892]

The last small item was to put the antenna tube in the boat. It was rather tricky to find an open flat spot on this hull but I eventually settled just left of the speed control. I drilled the hole about .015" smaller than the threads on the antenna mount and just threaded it into the wood for nice snug fit. The most tricky part of this was feeding the antenna through the mount and tube.

I think that just about covers everything in the build. This lovely Michigan weather has prevented me from doing any running of it yet but hopefully I can get a couple test runs in before the first club race in a couple weeks.
113973

[ray schrauwen]

Weather up here in Canada is bad too. Frozen solid still.

From post #68 down your attachments do not work. It would be nice to see your hard work.

[Fluid]

None of today's photos open for me. It is not uncommon to see some runout on some Octura collets.




.

[jfrancisco892]

I just re-posted all the attached photos so I think that should fix the problem. I have never had that issue before.

Anyways, my dad is going to machine the collet and put a bushing in in to get it to run true.

[jaike5]

This is a falsehood Ray,
I was down at the lake today and it is open water as far as the eye can see, now the wind was blowing to Rochester but not til a hundred yards out, before that it was like glass. a little cold today, tomorrow its clear and sunny and WARM! so to speak. I'll be down running a few boats checking out the winter mods.

Cheers, Jay.:w00t:

[ray schrauwen]

Cool, I'm working on a different vehicle as my Grandprix will not pass emissions. They changed the test this year, buggers.

That and the rocker panels are completely rusted out, tires worn out, no mufflers... time for the wreckers...:sad:

[Shooter]

Wow Jimmy. Nice work on all of this! It's about time!!!!

[tjcast]

114005 Here's a nice coupler

[jfrancisco892]

Thanks pete!

Tom what brand of coupler is that?

[tjcast]

That is a TFL one. I've run them for 2 years.

[b0atnutz3]

Jimmy you might want to put that turn fin on the inside of the bracket it will not flex as much as it will have the bracket backing it up. You can try to flex it as is and then switch it to the inside and do the same pull on it at the very bottom of fin bet it flexs more the way it is than it does mounted inside. Just my opinon not saying it won't work but have been down the turn fin road a couple of times testing and testing some more. Jerry

[jfrancisco892]

Just as a quick update as I mentioned the octura coupler was running out and I was gonna have my dad machine it out and put a bushing in it to fix the problem but it was a hardened steel and was not machineable. He tried to anneal it but unfortunately it distorted the flex cable side of the coupler. Anyway he determined it had .015 T.I.R. so I wasn't gonna use it anyway as I could visibly see the runout when spinning the driveline. I am going to try the MBP collet clutch and see if it works any better. It looks like a well designed and machined unit and it addresses the issue of the set screws cocking the coupler onto the motor shaft by clamping itself onto the motor shaft instead. I'll let you know how it works and what I think of it.

[detox]

Sometimes you can reduce runout by tightening the collet in steps. First step just lightly tighten, next rotate collet 180 degrees then tighten again, rotate another 180 degrees then tighten again. Do this until collet is tight enough so that no slip occurs.

I use a very light coat of Never Seize on interior wall of collet nut (threads and taper)

[jfrancisco892]

The issue is caused from the slop between the motor shaft and the id of the collet on the motor shaft side. Interesting idea though. Thanks

[flraptor07]

THAT is exactly why, I won't be using Teflon in any of my new builds.

Later,
Mike
Deffinetly! If you grease your flex after every time out like you should, then there is no need at all for teflon liner. You won't see any of my boats with a liner. And I've asked almost everybody in the club I'm in and 90% don't use liners anymore

[Shooter]

The issue is caused from the slop between the motor shaft and the id of the collet on the motor shaft side. Interesting idea though. Thanks

Ouch! I better check my collets for this. Probably can't avoid having at least a little clearance to slip it over the motor shaft. However, if it's excessive, it's no doubt going to run out on you and cause vibration, etc... Good catch.

[ray schrauwen]

I find many Chinese collets are very tight on the shaft BUT, the bore is fairly rough on some. How true they are is to be seen, some good, some were not.

[jfrancisco892]

Had the maiden run this weekend and overall it went pretty well. I started out with the 42x66 and it had a considerable amount of hopping in the back of the boat. A club member advised me that running a larger diameter propeller might alleviate the problem so I went to the Grim 45x68 which is supposed to be equivalent to the ABC H-5. It ran a little better with that prop but was still hopping. Then I decided to try the H-7 and the hopping got slightly worse. That was all I got on the first set of packs, so I threw in my 2nd set of batteries and re-greased the stuffing tube. From what I noticed it, the .187 cable and .250 brass tube with no teflon line is noisy if not greased thoroughly after every run. Anyway, I kept the strut depth the same but gave it some positive angle (prop pointing towards the sky) and this made the hopping worse. After that I put some negative angle on the strut (prop pointing toward the ground) and this helped quite a bit. It was running decently by the end of the day but still had a slight bit of hop in the back of the boat. I'll probably put about half a degree more of negative angle on the strut to fix that problem and fine tune from there. I'll probably stick with the H-7 for the first race as it seems like a good fit for this boat. I did check the data logging from the esc and the average amperage was right around 150. Maybe room for more prop? The turn fin worked like a charm as even though the boat was not perfectly planted on the water on my last run I had no problem holding it wide open around the corners. Hopefully it will have a good first outing this weekend at the first club race of the year. I'll see if I can get some videos from the race this coming weekend and post them up.

[Fluid]

All the props you used are lifting props, they will be more likely to cause hopping. Moving thr CG aft will help reduce the hopping, as will using low lift props like Octura x props.

Pulling 150 amps average is not bad for a Castle 1515/1Y, can't find the exact motor you are using. Actually, running the strut with a down angle at the prop end increases hopping as it lifts the transom. Can't explain why you see the opposite. Adding a bit of cup to the tips might reduce hopping, but a CG change is probably the best solution. Raising the strut a bit might also help.



.

[ray schrauwen]

You could try a D/T & back cut x642. Works well for some running a 1515 1Y.

[detox]

All the props you used are lifting props, they will be more likely to cause hopping. Moving thr CG aft will help reduce the hopping, as will using low lift props like Octura x props.

Pulling 150 amps average is not bad for a Castle 1515/1Y, can't find the exact motor you are using. Actually, running the strut with a down angle at the prop end increases hopping as it lifts the transom. Can't explain why you see the opposite. Adding a bit of cup to the tips might reduce hopping, but a CG change is probably the best solution. Raising the strut a bit might also help.



.

I agree with Fluid.

The m445 with a little cup added to tips will get that boat going well (2200 kv?). I bet you are running too wet on the front sponsons also....move COG farther back toward stern. Start out with 1/2" strut depth to prevent running too wet. If too loose (flyovers) try deeper 5/8" depth using setup board (adjust strut level with board). Strut Depth is measured from bottom edge of stern to bottom of strut resting on board.

Boat should plane smoothly on smooth water without bouncing on sponsons or stern (test, test, test). An good experienced hydro guy can get that boat going fast.

[jfrancisco892]

For the first race this weekend I am going to stick with the H7 just because I'm comfortable with a setup that I think will keep it on the water. Once I get some more time after the first race I'll start messing with other props and see what I can come up with.

[jfrancisco892]

Well on the first race of the year for the boat it blewover which I wasn't surprised by as I was in dirty water and it was a little flighty as is. Anyway some tape peeled back and a little water got inside (happened today on my Motley Crew at practice so I got rid of that roll of tape) and the BEC got screwed up on the speed control so I was done for the day. Put it in rice for about a week plugged it back in and like magic everything was working fine. Today I tried out the ABC H-10 which is a little smaller in diameter than the H-7 but has more pitch. It was running fairly well but just died on the second lap. Given the track record I assumed it was the speed control and sure enough it was. The boat is pulling a little to the right on the straights and I think the turn fin bracket might not be square so I am going to check that and if it isn't square it will likely get shimmed to fix that problem. I threw my eagle tree in just for giggles to see what kinda speed I am getting just to see where I stand. I checked it when I got home and I was thinking it was probably 54-55 mph. I was shocked to see 61.2 mph pop up on my eagle tree dashboard. With others running 1521s in the club I didn't have much hope in the boat but that speed gave me some faith in it. With some tuning and dialing in I think 65 should be feasible with this boat. I currently don't have another speed control to run in it so I'm gonna throw a p-limited setup in it (Aquacraft 2030 kv motor and Grim 45x68 prop) for Saturday's practice to get a little practice with it in that trim for the nationals which is about two months away. Although the speed controller got toasted I have some faith in this boat and feel once I get it dialed in it should be pretty competitive.

[fas]

What do you mean should be that thing can run with us with out problem you just need a little stick time to trust it

Fred