Jimi Findrix

Hey Crew,

It's me, Jimi again, surprise, surprise.

Here is the "NiMh Simulator Ballast Mk 2".
It now weighs 165g.
Now my 252g LiPo's will be adjusted to weigh in @ 417g.
Very close to my average Nimh pack weight of 421g.
33g more than my Tenergy 3800mAh NiMh packs. ("Surfcurls" standard pack)

Will this improve the surfing performance of my surfercompared tothis mornings experiment???
I am pretty confidentthatit will, once again reduce unwanted hull bounce..
But I am not so sure that it will totally eliminate it.
Anyway guys,from my perspective,it sure does seem like it is worth trying out.

Even an old mate who has seen my boards running on only a couple of occaisions saw me testing the board yesterday before I made the "Sim Bal Insert", commented;
"It seems to be bouncing a lot".
I responded with, "Yeah the waves are a bit bumpy today"
But I knew in my heart that he was right and that I had lost something special somewhere along the way.
That's when I really decided to try and come up with the solution and startedworking on the tail ballast concept.

I just can't wait to give it another run in the morning and see what happens next.

Sea ya.

JIMI
(Geraldton - West Oz)

Jimi Findrix

Hey Guys,

I can't help thinkin' how much this new piece of ballast looks like the big slabs of Hash we used to get to take on the road with us back in the 80's.

Man, those were the good ol' days!!!

Ha, Ha, Ha.....

Sea ya.

JIMI Kramercaster Findrix
(RC Surfing Heaven - Gero - W. A.)

itsfishi

mmmmmmmmmmm yeah i used to get great ballast when i was in the u.k. yes jimi the ggggooooood ol days.

Jimi Findrix

G'day guys,

First the good news.
Well the surf was very average for my test this morning but the board is definately surfing good again.
Even though the waves were quite sloppy the little Dude managed to impress me again.
He is doing some really nice airs now and you can really see the power in his back foot.
I will have to test in some glass to really assess how bad the bounce is now but it certainly seems to be a lot better
Now the bad news.
I had a lot of water problems coming from the rubber seals on the footpeg bolts.
The rubber is just not working for me, I will have to have a real think about it.
I will probably go back to using silicone again.
I will just have to take two decks in case an o-ring breaks.
When I got home I stripped the board to clean it and my new home made motor mount had snapped a leg off so I have to make another.
But I am still pretty stoked because I have now learnt quite a lot lately.

Sea ya.

JIMI
(Gero - W. A.)

R a i n e r

Any news about the centre of gravity (cg) of your new good surfing board?

itsfishi

hey jimi i just use hot glue on the foot peg bolt inside the board it actually does a good job, takes 5 minutes to dry, and is pretty easy to peel off when needed. i even use it to hold the servo in place, just get it nice n hot pump it where you need it and a wet finger will smooth it off.
good to hear the board is going good when do we get a video?
probably be aprill sometime before i get my board back in the water again, and then how it will run, well who knows.

Jimi Findrix

Hi Crew,
Well I made my second motor mount this morning, took about 2 hours.
It is screwing down tight and the cable shoots straight up the coupler.
My methods are quite crude, like a farmer, you know, not much measurements just hack away.
It usually takes me two goes at everything to get it just right.
The first one got bent around quite a lot while I was trying to get it to align properly.
This one just lined up straight away so hopefully it will last a lot longer than the first, lol.
 I have to get to work in an hour so I will clean everything this evening and have a look at those darn leaky footpegs.
Should be up and running by Sat morning, fingers crossed.
When I have got the board RTR I will try to assess the CG for you guys so you can compare.

Rainer,
Can you please post your boards current CG for comparison.
Wonder what Seb's is too.
If you read this Seb, could post your boards current CG measured from the nose.
This is great because once enough of us guys do a few CG measurements and tests, I am certain that we will all be having even more success with our models level of performance.
If we can eventually get a general concensus of the best CG point for the plastic surfer, then RC Surfers around the globe will benefit greatly from our research for sure.

I am certainly very lucky that my lifestyle and employment arrangements and also my location allows me to get into this so much and test various ideas so regularly.
As you know, it is very time consuming.

Sea ya

JIMI
(Gero - W. A.)

skowowski

Jimi, (aka "The Mad Scientist")

CG with no deck lid or battery is 36cm (14.25") This was measured from the tip and then running the measuring tape along the board to its CG.

Please take into account my winged fin has a lot of downwards thrust in it's angle and that my batteries weigh approx. 420g. Total board weight is 2.15kg ready to run.

Unless we all use the same batteries, use the same shafts and props, lead placements, then finding an exact CG is gonna be hard, but we will find a common spot. Having a heavy tail I find helps carving the wave, but it will bounce more. Have the majority of weight in the center or further forward and the board will do a 180 or 360 of every hard turn. I've know this from experience.

Hope that helps,
Seb (aka the retired scientist)

surfcurls

All The Info Is Fantastic !

Mad Scientist, Etc Nicknames Are Way Cool.

BUT, I Kinda Miss The Larry, Moe And Curly DAZE

No Hash Included ...

Jimi Findrix

Thanks Seb,
Your thoughts and experienceare always much appreciated.

As this CG researchis an extension of my battery ballast ideaI was kinda hoping you would include batteries deck and rider all bolted down ready to hit the water.

It seems a bit pointless finding CG otherwise.
As it is only when the board is in the water that CG has any significance at all.

If you get time could you please do it one more time with your pack and Lisa RTR style.

Thanks mate.

JIMI
(Geraldton - W. A.)

R a i n e r

Measure Lisa's CGcompletely set upRTR - right! That's the only CG, which makes sense.
I'll measure it as soon as I get home from work.

Take care!
Rainer

Jimi Findrix

Hi Crew,

I just got home from work and cleaned the hull out.
Here is a pic of the empty hull.
Note the new aluminium servo mount, I had to extend the plastic floor out towards the motor area.
I used some Jarrah, (Very hard West Oz redwood) and painted it.
Glued it to the front wall of the motor area and screwed it down.
Also the neo rubber stuck onto itacts as a shock absorber for the front of the motor to help avoid stress on the motor mount when landing big airs or getting dumped down hard.
That's the theory anyway but it didn't stop that mount breaking the other day.

I am going back to the shed now to start reinstalling everything.
Get back to you later on tonight with the CG measurement.
I gotta get it back in the water at dawn.
Even if there are no waves, I just wanna test out how well it seals and runs.

Sea ya.

JIMI
(Gero - W. A.)

Jimi Findrix

G'day RC Surfer CG Seekers,
My board is now RTR and I have done a quick CG measurement for you.

Seb,
Your comments about weight forward and weight back make good sense.
Obviously, what I am trying to do here is determine the sweet spot,
where the board can turn nice and radical but keep the bouncing to a minimum.

Rainer and Itsfishi,
With the new tail ballast plate and battery installed and the deck bolted down the CG on my RTR board is exactly directly behind the front heel of the Dude.
15" from the nose along the deck and 11 1/2" from the tail.

Without my new ballast plate the CG is about 1/2" forward at 14 1/2" from the nose and at this balance point my Dude surfs like a kook.

At this time I am not saying a 15" CG point is optimum because I need to do more tests,
but I can confidently say that the 15" CG is a very good place to start as I have already seen the difference that 1/2" makes in surfing performance.

It may be that 151/4" or 15 1/2" is even better but I have a feeling that if you go beyond 16" you will probably have trouble again.
But only knowingly and deliberately doing so will really determine if the board surfs better or not.

To anyone using an NQD RC Surfer regardless of what batterie,s props and other components, I highly recommend starting with a CG of 15".

Hope this is interesting and helpful.


Sea ya guys.

JIMI
(Gero - W. A.)

Jimi Findrix

Rainer,
Where is your after work RTR-CG? Hmmmm?????

Hey, last night I noticed that the widest point on the surfer also appears to be at 15"
Having the CG at the widest point makes good sense don't you think.
Also, now that I have moved the motor forward the back end of the motor is at the 15" point

Curlzy,
What is the CG measurement on a standard "Surfcurls" XT Pro Mod - NQD model with Dude and battery???
As I have built boards to almost your exact standards in the past I reckon it will be around 15 1/2"  maybe even slightly more.
That is just an educated guess.
I know this because I always add 28g up front on an XT Pro board
Come on Dude join in the fun and give us a number.

Hey guys,
Bazza Barrel (Brendon Heidtman - Wombarra) sent me an email yesterday.
He wants me to give him a call.
I guess the new board must be getting pretty close to a release date.
Very Interesting, I will keep you all informed.

No surfing test this morning, after weeks of high 38 to mid 40 degree C weather now there is a cyclone coming down the W. A. coast.
It is totally overcast outside, no wind and constant light rain with peels of thunder in the distance.

I should take the  time out to do a few tub tests.
 I think I will take one hose off and attach a hose to the port and pressure test for bubbles.
That is always a good way to really assess any weaknesses in all areas of the sealing.

Sea ya.

JIMI
(Geraldton - West Oz)

Jimi Findrix

Hey Rainer,
Are you still working?
When do you knock off?
Next year???
Spill the beans bro.

JIMI
(Gero - West Oz)

Jimi Findrix

Rainer,

I already know!!!
Your boards CG is probably 13 1/2" - 14", right?

JIMI

Jimi Findrix

Rainer,

To help with board comparisons be sure to measure along the deck.
If you measure along the bottom the extra curve will distort your measurement and make comparisons meaningless.

My boards CG is measured along the deck and RTR.

JIMI
(RC Surf Heaven - Gero - West Oz)

Jimi Findrix

Hello Again RC Surf Crew,
Having settled on 15" CG andpressure testing in the tub all morning, I have come to my next little problem.

My board leans heavily towards the left hand (Forehand for the goofy Dude) rail when floating on still water.
I have been aware of this for a long time but am now going to address the situation.

I really am gonna need 3 S packs the way i'm going 'cause I am about to add 130 - 140g of ballast to the right hand rail.
For the first time ever my board is gonna hit the peak perfectly balanced, but it sure is going up in weight with everysession.

It will be interesting to do another run time test with all this extra weight.

Hopethis box of leadnever lands on anyones head., lol.

Going back to work on it now.
I will get you an overall board weight shortly.

Sea ya.

JIMI
(Gero - W. A.)

Jimi Findrix

Yahoo, Alright Guys!!!

I just raced down "Shorie"s right on Sunset.
Just enough time for a 1 pack test run.
It has been offshore all day, the water surfacewas perfectand the swell is building from the NW due to the cyclone, our swell is usually SW.
There were a few sets with nice 3 foot faces but they were only breaking meters from shore running on an angle down the beach so it was pretty helly.
Man, this board is awesome now.
By farmybest board i've made so far.
Turning both ways equally well and does fast flat out donuts with a diameter of about 1 foot.
Sitting nice and level in the water, self righting quickly and planing as well as ever with just a very small amount of bounce at full speed but not too bad at all.
Enough power to dare to ride a few waves right to the death and just scrape over the back before dry very course rocky / shelly sand.
I did get caught on one wave and broke a prop on the dredging shoreline but just kept running to the end of the pack.
I was surprised that the runtime still seems about the same but I did not time it yet.
I also made an extension for the the battery / ESC which is a great improvement as there was too much stress on the deans without it.
I am really stoked with this machine now.
I am inching ever closer to a perfect RC Surfer, if there even is such a thing.

Also, I spoke with Brendon from Wombarra today, he says about 2 to 3 months until the new boards are on the market.
They are gonna come with a variety of tail shapes, pin, square, swallow and a 4 screw motor mount.
They are still working on the pricing but it sounds like they may cost about twice as much as an NQD for the stock model.
He reckons therewill bea few surprises and DVD all about the history of RC Surfing with the boards.
Wombarrawill be starting a new website soon too..
Man, I can't wait to see that.
He has been following us on the blog and says he will send me a hull to build up as soon as they get some samples.
Alright, freak me out, that is totally sick.
He also said hewould like tosponser me and send me a couple of hulls a year. Wow!!!
The hard yards are starting to pay off in more ways than one.
This hobby just keeps getting better and better all the time.

Should be some cyclone swell around in the morning, so I will be out on the hunt again at dawn.
Sea ya.

JIMI Findrix
(Geraldton - W. A.)

itsfishi

good sh#t jimi.

just been doing cg checks on my work in progress, kinda hard without new motor but old one is in there for weight , as you probably guessed the weight is forward with new battery position cg being around 13.5 to 14 inches from the nose thats with battery of 450 gram. i did not realise how much weight its gonna take to get the cg back to 15 inch mark, im estimating 200-300 grams maybe more depending on where its located, which kind of defeats the purpose of moving the battery to use as ballast, much rather be adding battery than dead weight,so im gonna play around with the layout and see if i can fit a second battery in, i think it is possible just not with the standard size servo.

mate im glad your testing is paying off for you. ear to ear grin after a surf=priceless.

Jimi Findrix

Itsfishi,

If you can get 2 packs in you will run for 1/2 an hour plus, that would be awesome, but how will you fit the radio ESC and servo in???
Geez, there aint much room to move in these little rockets, besides, you never know how the board will go with one in the front until it is up and runnin'.
I set the Low Voltage Cutoff Threshhold on the ESC down to 2.8v/Cell it was on 3.0v/Cell when I got 15 minute test runs.
I am hoping that has increased run time a little or at least compensated for the extra cargo.
ESC's weigh a fair amount and if you put that and your servo in the rear battery tray you may not need as much ballast as you think.
Keep goin' Dude I still think your onto something.
Yeah I think 15 is the sweet spot bro go for that for starters, no matter what it takes.
I just added a heap more weight to balance the rails but it only had a positive effect and equalized the turn radius.
Plus I find that the heavier board just smashes lips harder, jumps higher and lands airs so much better and also does way better floaters and rebounds.
By the way, speaking of CG.
What's happened to Rainers CG measurement, he has gone missing???

Sea ya.

JIMI
(Geraldton - Western Australia)

Jimi Findrix

Sebski Bro,

My board is now weighing in at 2291g, that is 141g  heavier than yours and mine is only 2S.
That is basically about the combined weight I have added to the side wall to balance side to side and the weight of the new servo mount.
So essentially my board is very close in weight to yours, but overal is actually approx. 4.7 bags of stinky buds heavier.

It's 1:00am, God, I can't wait 'till dawn.
Mad Professors don't sleep much you know. Lol.

What 3S packs do you use,?
I am gonna start lookin' at pack sizes with big mAh ratings to see what might fit my tray.
Now that I know how to balance my board with removable ballast, I can use 6 Cell NiMh  and  2S and possibly 3S LiPo's as long as they fit the tray and maintain the same board handling and basic surfing performance .
Yeah, 3S power, I think I want to try that  next.

Also, my new servo should be here this week.

Sea ya.

JIMI
(Gero - W. A.)

itsfishi

just been looking at low profile servos, using one of these may make it possible to get 2 batteries in but it will be bloody tight. you are right though, im just gonna concentrate on getting it up and running and see how she handles.

be careful using that 2.8v LVC as lipos dont like to go under 3volts and can be damaged permanently. ive always wondered why they even have LVC under 3 volt, i usually keep mine on 3.2 with hard cutoff to be safe.

rainer must be doing some serious overtime

i used to have a 5000mah batt same type as your 4000mah in the picture that fitted in fine. sadly it got wet one time and stopped working, but they fit and weight is 277grams.

total weight for this new setup is looking to be around 2kg and almost definatley 3 cell with slight chance of 4 cell but they are just so much bigger and heavier.

man i cant wait to get some cash, and get this thing together. it sucks being out of work with all the time in the world and no usable surfer, anyway doing the mods is fun.

how about a vid of the new setup if you can dodge that cyclone

cheers

Jimi Findrix

Hi Guys,
Well ya wouldn't read about it anywhere else.
I went to "Stockfence" this morning.
The waves were perfect 2 -3 foot and I sent the Dude out but everytime he got more than ten feet offshore he just cut out.
Now I tried for 3 hours to sort it while the perfection just kept on pumping through , to no avail.
This was the best quality RC surf I have seen since winter, absolutely beautiful really long lefts meeting up with perfect rights that run into the shorebreak.
I can't believe the board went so well yesterday evening and this morning it was all ****** up again.
I tried everything with the radio conections but ended up concluding that was not the problem anyway because I have had this same problem on and off for a while with my other radio and this is a brand new one I just put in.
I am certain that it is the Deans plug on my old ESC as it had a wire off yesterday and my son in law soldered it on for me just before the test run and he warned me that it would not last very long because he used a ****ty iron that I had laying around and reckons it does not get hot enough to do a good job.
Well after the test I thought it would at least run for a few sessions.
Boy was I wrong.
I am exhausted and a bit pissed off because there was nothing I could do but watch perfect surf going unridden and no matter what I tried I could not get out to it.
The surf was thumping on the shorie and everytime I tried to get the board to run it ended up grovelling in and getting slammed on the sand really hard.
I am surprised nothing broke, especially the Dude, he is not even showing any signs of stress aftrer dozens of really hard poundings.
Anyway I have a new deans plug, but I am hopeless at soldering and I only have the cheap crappy poxy iron but I am gonna try and get it running this arvo because the waves are getting bigger and it will be perfect offshore all day.
Also, the bloody rudder hatch is leaking into the hull again and I have to drain it out through the little hole in the nose after every pack.
I swear, that rudder hatch is the biggest problem of all with the NQD, everytime you seal it, sooner or later it starts to leak into the hull again.
Ive gone from heaven to hell in less than 24 hours.
Finally, now that the board is balanced back to the equivelant of when I was using NiMh I am using 28g in the front again this just seems to help with steep take offs and seems to pull the nose over the edge.
It is such a small amount of weight that it basically has no significant effect on the 15" CG, but I will check that later on.
God, I hope I can get it to run this arvo.
I have 2 new ESC's so I think it is time to get one ofthose fitted with Deans and bullets because although thisone I am currently using seems to run ok when the Deans is soldered properly, it is gettingold and has been inside abloody wet board manytimes, luckily it has silicon in the endand is heavily taped up, but I am getting a bit suss on itso I think a nice new one will help get some consistency back.
What a real bummer
I am gonna stick a bit of solarres in that leaky rudder hole now, I hope that seals up the hull again otherwise it could be the new stuffing box that is leaking.
So close but yet so, so far away.
These things are a constant nightmare but I love 'em.
What a ****ing grovel.

Sea ya.

JIMI
(Gero - West Oz)


.

Jimi Findrix

Ok Crew,
I slapped a bit of solarres around the rudder shaft hole.
Soldered a new Deans on the ESC with my cheapo iron and raced back to "Stockfence".
Well it was glassy light offshore and the swell was still building.
The odd closeout but mostly peeling.
I chucked the board in over the chest high shorebreak and it did the same thing as earlier, stopped just beyond the shorie.
Then all of a sudden it was going ok.
So I ran it for 2 packs and got some filthy long waves with 2 to 3 foot faces and the board was planing even better with my trusty old 28g back in the front.
After a couple of good packs I pulled the tape off the front and drained some water out, not as bad as before but it is still gettin' in.
I put in another pack and got a few great waves then did a big air and it stopped in its tracks.
It got washed in and I saw that the battery had slipped into the coupler and the motor bolt I used to replace the grub screw on the coupler had chewed right into the plastic case.
Think I better put some Velcro up the front of the tray next time, lol.
Anyway, I gave it a wipe out and squeezed out the water from my sponges 'cause they were gettin wet.
Put another pack in and sent it out again,this time the cable on my propshaft snapped.
It got washed in again and I noticed that the lid hadI pushed down on the motor a little bit and the coupler was slightly higher than the end of the stuffing tube.
The board is lookin' trashed again now and despite my best efforts, itis still just a leaky old NQD.
But it was shredding for a while there and I even got it totally barreled right on the shorebreak and I mean literally as the wave peeled onto shore and then closed out and left him washed up on the sand.
I really push my boards so ****ing hard that I am starting to think that it is impossible to build one that can take what I throw at it sometimes.
The only thing that makes me think it can be done is Seb's board.
He pushes that thing so hard it is not funny and if he can build a board that can take that sort of punishment than so can anyone else.
So my board is in a state of total destruction again now and it needs to be stripped and cleaned again.
I wish I could work out why it is going intermittent some days and runs perfectly well on others.
BloodyGremlins.
Regardless of all the problems and destruction my board has gone through todaythe two packs that went wellwerea real blast.
I think I will start building my next board and put a new ESC in it and all the other mods I have done recently.
This hull is trashed but is still usable I suppose.
I just can not keep the water out, but then again, it was getting heavily dumped right into the sand on the shorbreak quite anumber times today.
I just can't believe that the Dude is taking that amount of punishment, not even an o-ring broke.
Many times Iexpected to see broken arms and hips for sure.
I just run over pick him up and throw him back out over the shorebreak and run just beforethe wave finallyexplodes in front of me.
Man that is a good RC Surf Spot.

Sea ya.

JIMI
(Mr Damage - RC Surfers Heaven - Geraldton Western Australia)