How to tune stepped mono for racing?

[Jesse J]

I have several now and would like to see how people set theirs up and what kind of races they are in.

I'll post up mine in subsequent posts, but they include:

H&M 3 step chief 34"
Hopf cyklon 1 big step (I'll check spelling) 32"
And now a syncron 2 steps (thanks Joseph) 28"

If you have a stepped mono please share your experience.

[photohoward1]

In IMPBA and NAMBA. stepped monos are considered hydros. They are not allowed in the mono classes.


Sent from my iPhone using Tapatalk

[NativePaul]

Are stepped monos allowed in your Offshore classes? I guess they are as stepped cats are allowed in it. As a Naviga racer I have thought for a while that a Naviga type stepped mono would do well in P ltd Offshore, and maybe one of the bigger ones in P Offshore too. On the other hand I have never seen one with a COG as far forward as you may need it now NAMBA have banned self-righting, maybe they would hook like crazy at 30+%.

[Fluid]

In IMPBA and NAMBA. stepped monos are considered hydros. They are not allowed in the mono classes

NAMBA classifies stepped monos as Offshore hulls.

The preferred CG will depend on the location and depth of the steps. Different makers seem to have different ideas on hull bottoms of stepped hulls.




.

[Jesse J]

thanks for replies guys. i fear she will be a journey of adjusment-run-adjustments.
I have copied from video section: yesterday's video (https://youtu.be/jpQghSadSfw)... thoughts?

[NativePaul]

Pirosteel on here is Joseph Toth whos company is ToysPort, he designed Syncrons, built them, has fitted out dozens of them to sell ARTR, and has raced them, he will be able to give you the best setup advise for that one.

Different makers did have wildly different ideas on Mono steps, 20 years ago stepped monos ran with riggers and cats in our hydro classes, and when the powers that be realised that was ridiculous and decided they were Monos, many different directions were chosen. Hopf's big single steps were very efficient and ferociously fast in a straight line, but tended to ching around corners, Tenshock's dual stepped hulls turned really well but lost too much in the straights, I think the Chief may as well be unstepped for the size of the steps and I would try setting it up as if it was. With nearly 2 decades of development steps have converged pretty closely around an ideal for the Naviga course, and for the last couple of generations (5+ years) all the race designed stepped monos have had single steps of roughly the same size and in roughly the same location, while hull size, deadrise, lifting strakes, spray rails, ride pads, nose pads and aero change according to the conditions the designer wants the boat to excel in.

Your Chief looks a little wet, but you are running in good conditions alone, in race water it may be perfect. Do you have self righting and if so are you allowed to use it? Are your races long enough to benefit from it? We tend to run our stepped monos at around 27%, but we race for 6 mins and if a self right takes 5 seconds, just 1.4% extra speed makes that up. If however you are running a minute and a half sprint race, you need to go 5.9% faster to make up for a roll over, which is very unlikely just from moving the CoG back a few percent. Even for a 4 minute Offshore race you would need to make up 2.1%. It seems Like you would be better off running wetter and safer and throwing your extra power at it.

[Jesse J]

Thanks Paul, sounds like a different world across the pond. Here I would be pretty much limited to p offshore, therefore will try your suggestion. I have heard mixed reports about the legality of self righting, so will not plan on it.

Do you guys do much tuning with strut depth or angle?
Weight back and behind the front step, is what I'm hearing.

[NativePaul]

I will caveat this with telling you that I was a cat guy, and now race riggers, I am not a Mono guy so I don't know the exact and measurements, I have given it a go in the past, but I wasn't too keen and my own stepped race mono was designed back in '08, I have not raced it for years, and it would be hopelessly uncompetitive if I tried to race it now. They are however the most popular classes here, I see them all the time, and the standard is pretty high. My last club had the current Mono2 (4-6s) world champ in it, and my current club has a former world Mono2 champ in it. I can give you generalisms and rules of thumbs, but if you want to know specifics I would have to ask one of the mono guys.

There is little or no prop depth angle or length tuning, all monos have the motor mounted as low as possible in the step, and the vast majority use a straight alloy, carbon, or alloy and carbon stuffing tube, with a fairly thick for the power (2mm for Mono1 (around 500W) and 2.5mm for mono2 (around 1kw)) piano wire drive, and at least one intermediate bearing in the stuffing tube to reduce the whipping intrinsic to a straight shaft. The prop hub is placed close to the line following the step and transom. If you get the depth or length of the prop wrong you unglue the stuffing tube, oval out the transom hole reglue it and try again. There are exceptions, most notably Rasch makes a carbon fibre angle adjustable stinger that many of his customers use for ease of setup, and his boats have a lot of aero lift so the weight is not as critical. All props are very low lift types and with no ears, usually Tenshock CNC, Graupner Carbon, Dr Prop CNC, TP CNC, not the Octura clones in rages that include them like TP and Doctor Prop.

Sorry, I don't usually take static shots, so these are the best "shaft" shots I have on my PC, 2 typical stepped mono straight shafts, and the Rasch carbon stinger, all on well set up boats despite the aerobatics in the photos but if I post more typical photos you cant see the shafts. the number plates are all about the same size, that is a Mini Mono, a Mono1 and a Mono2, so although it looks like the step size is getting smaller on the lower pictures, it is fairly consistent, it is just proportianally smaller on the bigger boats.
http://i22.photobucket.com/albums/b310/nativepaul/a_6045.jpg
http://i22.photobucket.com/albums/b310/nativepaul/a_6146.jpg
http://i22.photobucket.com/albums/b310/nativepaul/218.jpg

[Jesse J]

Dang, you is a greased weasel!!

Thanks for info. So os you're stinger perpendicular to transom and just gets moved up or down?
Low lift props, and straightest wire drives. Got it.

How do you make them turn well? Mine want to turn flat... is this common?

I got a synchron from Joseph and it likes to hook... my inclination would be to raise strut.. but he told me it won the 1999 races... I was wanting to make it run like it did when he made it win.

[Fluid]

Hmm, I suspect that the speeds in the last millennium were considerably slower than they are today. Maybe slowing it down will help....


.

[Jesse J]

Bah! Would Tom Taggart agree to SLOWING down?!? Or adding weight? Or letting up?
Ok, fair enough, slow it down or change the strut depth. Of course I can't argue with the man who wrote the book on FE racing....

[NativePaul]

Stinger/stuffing tube/driveline should be at a slight angle to the transom if the transom is upright (which it may or may not be).

Speeds are definately faster now, but maybe not as much as you expect as they keep adding runtime to our races in order to moderate the speed. If I recall correctly and I am not sure I do, we had swapped to brushless back then so motor efficiencies were similar, batteries were NiMh of about 3300mAh and run time was 4 minutes, now we have about double the capacity but 6 minutes runtime.

The biggest change would be weight in 1999 it would have run 12s sub C weighing about double what a 5000highC or 6600low pack, I would try running 4s2p with both packs on the left to simulate how it would have been with NiMh.

Hooking is often a Cog too far forward, or could be a rudder angled with the bottom further back than the top, A prop with too much lift can make it hook with the power on too.

[Erik Aa]

Would an octura prop (say x437/3) work in a stepped mono if you detounge it?

Best,
Erik

[NativePaul]

I haven't seen it done sucessfully, but maybe if you detounge the hell out of it for efficiency and cup it to reduce lift

[Jesse J]

What prop would be good start? Now I have an x442 and AQ 2050 motor on 4s

Also, do these things turn flat or bank?

[Jesse J]

Also, can someone direct me to the specs on these three classes, mini mono, mono 1 and mono 2?
Like, hull length, motor / battery limitations, race course length, duration.
Any other specs would be great.
Even though we don't have these races here... I may try to get something going at the club level.

[Erik Aa]

http://www.naviga.org/index.php/en/regelwerke/category/6-m?download=40:m-class-rules-2016-annexes

[Jesse J]

Thanks Erik! So the three mono classes are divided by total battery weight and max cell count And that's about it.
Are setups pretty secret, or do racers share their secrets?

Wait... Mono 1 can really only have 280g of batteries? :scared::scared:Or is that per cell?:blink:
That is a 3s 1400 mah pack! How can it go for 6 minutes?
Help me if I'm reading this wrong.:confused2:

[Erik Aa]

Mono 2: http://boattroubles.myfreeforum.org/Data_of_Mono2_Exiga__about549.html

Mono 1: http://boattroubles.myfreeforum.org/Data_of_World_Champion_Mono1_Envoy_about543.html

[Erik Aa]

3s naviga legal 5000 mah < 280 grams. http://eshop.mmodely.cz/tenshock-lipol-5000mah-3s-20c-naviga-p70952/?currency=eur

[Jesse J]

Awesome, thanks!!

[NativePaul]

It is for the full pack including any wires connectors and velcro etc, everything attached. There is a fairly big weight difference in High C cells and the low C cells we use, a high C 2s 5000 would normally be around 300g, and you can get 3s of the same capacity under 280g. 3s 1500-1700 Low C would be <110g for the mini classes. you don't get something for nothing though, and the cells are rather fragile.

[Jesse J]

What motor do you guys use for mono1 on 3s?

[NativePaul]

Leopard 2860 3400 is probably the most popular, Lehner 1530/8 is probably the best that is popular. However I do know someone that switched from the Lehner to an equivalent 11 series Neu (probably a 1112/2d but I am not 100%) and loves it so that might be the better option for you guys over there if you want high end.

I hear Neu have moved their production to China recently though so maybe they are not as good as they were, I know hackers efficiency dropped through the floor when they switched from Germany to China, have you noticed the same from Neu at all?

[Jesse J]

Unfortunately, we have some reports of quality degradation over the last year or two.
Thanks weas, I'll see about that size.

[Erik Aa]

Mono 1:
http://www.electrafying.com/setups/ETTI%20Envoy%20Mono1%20setup.pdf

http://www.electrafying.com/setups/Asylum%20Nutcase%20Mono1%20setup.pdf

http://www.electrafying.com/setups/Motor%20mount%20&%20shaft%20installation.pdf

[Jesse J]

Jackpot! Thanks buddy!

[Jesse J]

where would one find such hulls for purchase from the US?

[NativePaul]

I doubt you can find one in the US, we don't even have them for sale in the UK and we race them, we buy direct from the manufacturer in mainland Europe or Asia. I think you have a H&M dealer in the states (Is it rocket city racing? Not sure, for obvious reasons I didn't pay it much attention) and they could order you a Skyper mono1 or a Speedman mono2, but I doubt they would have them in stock.

[Jesse J]

Mono 1:
http://www.electrafying.com/setups/ETTI%20Envoy%20Mono1%20setup.pdf

http://www.electrafying.com/setups/Asylum%20Nutcase%20Mono1%20setup.pdf

http://www.electrafying.com/setups/Motor%20mount%20&%20shaft%20installation.pdf

Hey Erik, would you have similar for mono 2?
Namely, what motor and cell count, 3s2p, or 6s1p?

[Jesse J]

Here is my latest test with Joseph's syncron.
https://youtu.be/KlMfhS_b8dw

[Jesse J]

Does anybody know of someone who has gotten the H&M chief tuned well?
I'm oh so curious. I tried a big turn fin and she banked OUTWARD!!
How dat work?

[Jesse J]

Mono 2: http://boattroubles.myfreeforum.org/Data_of_Mono2_Exiga__about549.html

Mono 1: http://boattroubles.myfreeforum.org/Data_of_World_Champion_Mono1_Envoy_about543.html
Hey Erik, do you know of any more recent setups, a lot has changed in 5 years.

[NativePaul]

I tried a big turn fin and she banked OUTWARD!!
How dat work?
Your turn fin is still canted over too much and as it is slipping sideways the angle on the fin is forcing the that side upwards, so the bigger the fin the higher that side will ride, and you need to stand it more upright to remedy it. I felt sure I mentioned that as a possible issue earlier, but now reviewing the thread I can't see it, maybe I posted in a different thread, but whatever, the effect of the bigger fin confirms that it is at the wrong angle, and extra lift at the rear during turns would also explain the hooking , so you may cure both issues with a single easy fix.

The setups Erik posted are still valid, Mark Shipman is still running both of those boats and still competitive with them, he is the clubmate I spoke of earlier that switched from Lehner to Neu, although back when those were posted he was still running the popular Leopards I mentioned.
Dee is ETTI's team and test driver so he always has either the latest hull or a secret project and isn't driving those any more, but as I mentioned before the differences between hulls is shrinking as they are converging around the ideal for the course. We only have about 10% more power than we had in those setups, and while there are newer and better all round boats, they are still absolute beasts in calm water conditions, and the setups for the new ones which have a few more degrees of deadrise and a lot more hydro nose lift that is out of the water 95% of the time will be very similar indeed.

Leopard 3674 1700 are a popular motor for 6s Mono2

[NativePaul]

There was a race last week and I took some pictures of the rear end of well set up monos for you, I was horrified to find out that when I was taking the photos peope were thinking i was working on a mono myself, so I didn't get out a tape measure and angle gauge.
http://i22.photobucket.com/albums/b310/nativepaul/DSC_0220.jpg
http://i22.photobucket.com/albums/b310/nativepaul/DSC_0212.jpg
http://i22.photobucket.com/albums/b310/nativepaul/DSC_0217.jpg
http://i22.photobucket.com/albums/b310/nativepaul/DSC_0216.jpg
http://i22.photobucket.com/albums/b310/nativepaul/DSC_0207.jpg

[NativePaul]

http://i22.photobucket.com/albums/b310/nativepaul/DSC_0214.jpg
http://i22.photobucket.com/albums/b310/nativepaul/DSC_0215.jpg
http://i22.photobucket.com/albums/b310/nativepaul/DSC_0211.jpg
http://i22.photobucket.com/albums/b310/nativepaul/DSC_0213.jpg
http://i22.photobucket.com/albums/b310/nativepaul/DSC_0222.jpg

[NativePaul]

http://i22.photobucket.com/albums/b310/nativepaul/DSC_0210.jpg
http://i22.photobucket.com/albums/b310/nativepaul/DSC_0194.jpg
http://i22.photobucket.com/albums/b310/nativepaul/DSC_0206.jpg
http://i22.photobucket.com/albums/b310/nativepaul/DSC_0205.jpg
http://i22.photobucket.com/albums/b310/nativepaul/DSC_0200.jpg

[Jesse J]

Sweet, thanks Paul! Ok, you've convinced me... I'll go vertical.
Yes you did tell me, I just haven't had the time to redo the turn fin.
Gonna make in as deep as the keel and 2" wide, sound like a good start?

Thanks again for the recon pics, and for going under cover as a mono guy.

[Jesse J]

Question: has anybody run the Skyper mono1, or speedman mono II by hydro and marine?

The skyper call it an open flood chamber? Is this accomplished by weights to port side?

Any comments on setup and performance of either/both?

Skyper: https://hydromarine.de/images/product_images/popup_images/958_5.JPG
Speedman: https://hydromarine.de/images/product_images/popup_images/Speedm_85.jpg

[CornelP]

Hi Jesse,
I had both in my hands: the Skyper was mine and I raced it for about two years, the Speedman I installed for a friend. The open channel in the Skyper is a pain in... you either partially close it, add weights or install a small internal chamber they usually provide. As performance, it was very good, but not something impressive, due to the fact that it was a bit on the heavy side. It was actually replaced by the King Cobra, which is the same hull with a different (normal) top.
The Speedman was a joy to build, excellent quality and it ran perfectly from the first test. Two years ago, at the Naviga world championship, there were still a couple around doing well.
In brief: good hulls, but they are almost obsolete... As options, consider newer ones, like the Etti Sirius for mono 1 and the Rasch Tomcat or QEssenz for Mono2 (I am in love with this one).
http://raschmodellbau.eu/Boote/Q-Essenz-Mono2
http://raschmodellbau.eu/Boote/Tomcat-M2-Mono2
Cornel

[Jesse J]

Hi Cornel, thanks for your input; how does one order one of these from the US?
Both are beauties, but I'd prefer the tomcat.

[CornelP]

I think you can contact him on the website, he usually answers within a day or two.
You can also ask him to install the floodchamber and ask for a race spec (lighter but a bit more expensive).
Cornel

[Jesse J]

So, now a question: what is fun sport class? This chief is proving a significant challenge.
What voltage/motor/prop are guys running this on?
Thanks

[NativePaul]

Hydros.

[Jesse J]

What??? That is the class H&M advertises this chief boat as... bah!
I'm getting the idea that nobody races this hull...

[NativePaul]

I didn't really understand that you meant by "what is fun sport class?" and tried indicating that Hydros are more fun classes to me. I was just joking though, stick with it and I am sure you will get there in the end. Where are you at now?

I am now understanding that you think "fun sport" is the name of a race class? If so you are mistaken, all the surface drive mono classes have Mono in the name, there is Mini Mono for <450mm hulls with <110g 2-3s battery, Mono1 with <280g 2-3s battery 6min, Mono2 with <560g 4-6s battery 6min, and their used to be Mono3 with 20 SubCs 6min (but it was killed off when LiPo came in). There are also submerged drive mono classes Eco <280g 2-3s 6min, Mini Eco <110g 2-3s 6min, FSR-E <840g 15min, F1-E speed, and F3-E steering.

While H&M make some great race boats aimed at the Naviga classes they only constitute about 1/3rd of H&Ms hulls. Most are semi scale boats for fun running, sport running, powerboating or whatever you want to call it, running either solo or in a club but maybe without even having buoys out to make a course, and not against a clock. I think they put funsport in the competition class category to indicate that it isn't made to fit a class.

I have never seen a Chief racing and nor do I expect to, it is a good looking fast scale boat, but it is very big for a Mono 2, maybe small Mono 3 size if it was still going, it has a very high deadrise, and has rather a lot of freeboard, all of which could make it a good very rough water boat, but count against it in typical conditions. However the rear overhang is just dead weight, the engine bulges would slow down self-righting considerably, and the 3 steps are too short to be of much use at model size.

[Jesse J]

Dang, me so foolish! Now that you spell it out, all makes sense. I did buy it for its looks... recon I'll keep at it and not try to race it competitively.

Had it out last time, but just as it hit full throttle, me stub broke loose from the wire, so still don't know how vertical turn fin works. Should have another go this next Saturday.

[Jesse J]

I am in contact with randolf and am about to order me a tomcat m2 with flood chamber.

[Jesse J]

Last weekend I think I got the mix closest so far. Hacker 8xl, 4s, m645 prop, strut 1/2" up from keel and down 3-4 degrees. But, was still chine walking severely as every time I've taken her out. I think this is what is causing the problems in the turns and instability in the straight line.

So, I Got me a "lift strake sander" and went to town on the chief.:bash:

This Pneumatic sander was just made for this project!
My little 1.5 gal air tank made the process take 4 times as long as it should have.
About an hour of sand until pressure drops and sander stops (5 sec) wait for pressure to build back up (20 sec) then repeat. I'm glad I wore my respirator, ear plugs and safety glasses... that fiber glass is nasty!

[T.S.Davis]

Late to the thread but thought I'd share, If you;ve already figured all this out I apologize.

Stepped monos are defined by both organizations as hydroplanes. NAMBA has an electric offshore class in which steps are allowed. IMPBA has no electric offshore classes at all. We run them. They're just not in the book. Major difference being that most IMPBA venue run offshore as a sprint instead of a timed heat with most laps winning. I've not seen the Chief up close but the website claims 880mm or 34-5/8" Makes it Q.

Great pics Paul. Something I noticed that's different on most of those than what we typically see on step-less mono. Big turn fins and they are square to the water instead of square to the bottom. Interesting...... Maybe this is why I've seen one turn well. It also looks like the prop is very far behind the trailing edge. Farther than the typical stinger strut we tend to use on mono hulls.

[CraigP]

It's been my experience that prop behind the rudder induces understeer. Maybe that keeps them from spinning out?

[NativePaul]

The Fins are almost vertical but you can see in some of the pics that there is a degree or two of hook angle. I don't really know how your boats work with the fins hooked the wrong way at the entry and exit of the turn, do you run a much deeper rudder? The fins are indeed bigger in proportion which is I think due to our course dimensions, the Naviga oval is 60m (66yd) straights with a 5m (5.5yd) radius on each end for a total length of about 1/12 mile, I know your oval is 1/6mile and straights are much longer, but from the videos I have seen your turn radius looks much bigger too (what is your radius?).

Another difference is that you won't see a trim tab on a Naviga Mono, but you guys seem to fit them right off the bat, before you have even run the setup to see if it has any naughty handling defects that need them fitting to rectify.

I hadn't noticed the "stinger" length difference, maybe that extra leverage helps to explain why we need lower lift props (as well as the straighter shafts), and why we run higher KV than you despite using a lot less power (to use much smaller props that walk less). I am however not mono knowledgable enough to say why the longer shaft. As they are prop riding it is effectively extra boat length that is almost free of weight and drag penalty, but I suspect that there is more to it than that.

[NativePaul]

Some are prop behind rudder some are side by side and some are in front, all have close to vertical fins.

If you are getting understeer you can fix it by: moving the rudder back giving it more leverage, increasing the size of the rudder or reducing the size of the turn fin, which you should do depends on what course conditions you want to run in, other handling traits the boat has, and how hard it can turn compared to the radius of your course. As far as I know, moving the prop forwards won't help (if you maintain the same CoG).

[T.S.Davis]

Paul, course size depends on the venue. It can vary. There is some fudge room on the dimensions as long as each lap is 1/6th mile but for many courses I've setup the radius was 35ft. Our home pond is 35'. Pretty sure the idea was to allow ponds that were short and fat or long and narrow to still place a legal course.

The turn fins on our mono aren't in the water typically when going straight. At least mine don't. It they do it's just the very tip. The only time they really touch is when we turn. So we place them perpendicular to the running surface while turning. Looking at the naviga setups it appears you use the fin to help keep the boat traveling straight. Is that accurate?

On the tabs. Speculation on my part here too. Your boats are riding thrust where as we are using the bottom more. If your stepped boats do weird things you wont know since they run like hydro planes with multiple wetted surfaces. If you capsize, you wait, self-right, and continue. If we capsize we're done. So we tend to run a wetter setup. Hence, using the bottom of the boat more. I like to setup my mono so that they fly flat if they come out of the water and then use the tabs to decide how much I let them fly. 30% plus CG from the transome. What do you guys shoot for with CG on the steps?

Truth, I've not spent much time with stepped mono. They seem such different animals with the steps. I was watching this thread. That Chief is such a beautiful boat. I was hoping someone would figure it out.

[Jesse J]

Thanks for all the great input, yes she is a looker. I'm really optimistic about delifting her and bringing her more like our wetter monos. Having three steps, each lower toward the transom, she is kinda hybrid; stuck between the big euro steps and our nonsteps. Hope to get her out this weekend for a test. I have also gone another inch on rudder since she never has hooked up in the corners yet. As Paul has recommended, I have a vertical square turn fin and have added another reinforcement and sturdied up the bracket.

[Jesse J]

H&m skyper 1 Kevlar carbon ❤️
Ordered June 1... got it today from rocket city in Orlando- Brian be safe brother!

26.5" x 7.5" at transom
4" chamber behind and 3" in front of step.

Odd lil guy. Gonna set him up for mono 1, then race in N2 offshore with HOTMBC crew. Here are some shots of our chihuahua with a boat for scale.

I'll be referring to earlier posts on this...

Not giving up on chief, just with all the bull Harvey, I can't feel too good about playing until I help out some flooded folks.

[NativePaul]

I would be putting on waders and running in the main street.

[Jesse J]

Got her set up with some euro help...

[Jesse J]

Help me figure out elegant turn fin bracket...
Please?

[NativePaul]

On riggers and monos without much transom depth we generally cut a vertical slot on the transom, and glue in a piece of carbon instead of using a bracket.

Not a mono, and not a turn fin, but you can get the idea from the start of this video.

https://www.youtube.com/watch?v=A7S_ZJSi4gM

[Jesse J]

Thanks Paul. I think I saw you faffing around in there... but it was high speed faffing!

I had glued a bracket I made into the groove on the far starboard just before I saw your post...
then I ran down, pulled out the bracket, wiped off all the glue and cut through the hull along that groove. I slopped a bunch of glue into the groove and then pushed the bracket down into the groove.

Thanks for posting the vid, it got me visualizing that mount popping out since it wasn't anchored into the hull.
I'll post a pic once it's cured up.

[Jesse J]

Gotter licked!

[CornelP]

Hi Jesse,
I do not know if you are aware of this:
http://hydromarine.magix.net/all-albums/!/oa/6437456/
some of the best resource for H&M boats...
On mine, I ended up with an oval turnfin that was touching the water a lot less and it was ok.

[Jesse J]

Hi Cornel, thanks for the link... but it's not working?

[NativePaul]

It works for me, are you at work, if so try from home as IT may have blocked galleries.

Interestingly they show one with an angled out fin, one with a vertical fin and one that looks like it has an angled in fin.

The camo boat looks like it is one of Bernd Weiss's from the colour scheme so I would follow that setup as his boats always rip, but they don't show the fin on that one.

[Jesse J]

not at work, on mac and ipad - no worky for me...

BUT, I did make this (https://youtu.be/S5CFwagaRFI) today.

I was able to get 3 and a half minutes on 3300 mah, and all electrics below 110F.
pretty happy with first results. Now if I can get this thing to self right in under 2 minutes...

[Jesse J]

link doesn't even work on my PC... wonder if its a US vs Euro thing?

[NativePaul]

Could be I suppose, i dont know why H&M would restrict their content though as they are trying to sell workldwide. Try this one, it goes to the gallery instead of the slideshow, so it may be simpler for your browser to process.

http://hydromarine.magix.net/all-albums/!/oa/6437456/mode/matrix/

[CraigP]

The link worked for me, I'm in the States... Nice pics!

[Jesse J]

Even when I go to the hydromarine.de site and navigate to this page: https://hydromarine.de/shop_content.php?coID=19&MODsid=574hkpkkb1hrdkes95dc8m09g4 - it doesn't load... Firefox nor chrome on mac... not IE On pc !?!?

[Jesse J]

Tried again.. but man it runs like crap now: https://youtu.be/uQ3SCami-fI

so I propped up to a 40mm, then back down to 38mm and both made it behave like an idiot.
I will need to move the ESC back behind the motor and add ballast to get the CG behind 33%

do you think the prop needs to be higher? the prop closer to the transom? it sure aint fun driving it like this...

[CraigP]

Jesse, I see just one turn fin, on the starboard side. It looks like it’s running in the water while going straight. On my Mono, it’s real important to have balance, both in weight and drag components. I have two turn fins on the back, both are set high enough so that they don’t get wet going straight. Have you tried a setup like that?

BTW, is the self fighting using a flood chamber or outrunner motor? I like that!

[rol243]

normally the port side turn fin is only needed if your going to be turning left abit. if the hull performs well with only 1 x starboard fin fitted than leave it at that, saves on extra drag as well. looks like alot of rudder throw too. [ drop it down ]

[CornelP]

Jesse, I ended up using a 35mm prop on mine, running around 37000rpm and it was quite ok. Another guy here used a 3 blade 36 and it was a lot more stable.
Try a smaller turnfin or angle it a bit. No need for a second one on a stepped hull, it's just extra drag.

[Jesse J]

Ok, I'll prop down and try again.
I was going off Paul's comment that speeds looked low and that other naviga racers are using 40 mm props.