New Member New Project With A British Twist

[Basstronics]

Can you run 4S?

I dont know squat about boating rules for classes, I run for fun.

Seems most people having good results are running 4S setups.

[British Bulldog]

I'm quite happy to run 2s at 5000 if a 3300 or a 3600 will give me a reasonable competitive speed ( at least in the 30's ) and the endurance time on the lipo. this is quite a learning curve for me, brushed motors i have no issues with but bl that's a whole new ball game.

im sorry the batterys availble to me for the class are,7 max sub “C” (43mm x 23mm nom.) NiCad or Nickel Metal Hydride cells or Maximum 2S1P 5000mAh LiPo or Maximum 3S2P 4600mAh A123

[NativePaul]

My last runs were with a 3656 3000Kv @ 3s 4400 40C batts and K42 prop for 38 MPH @ 180 Amps.

So about 1.8KW to push a 26"mono at 38mph, that sounds pretty inefficient, I'd be surprised if bulldog doesn't get at least that speed using < the third of that power he has available to him as a Mono1.

Living in Devon will you be racing with SWAMBC? if so you will be limited to 2s and 5000mAh, I know several guys that have not changed their motors from 2s to 3s and are at over 4000kv but it pretty much precludes you from using Octura props, Graupner carbon or Tenshock CnC have a much lower loading and will still let you run a semi decent size 33-35mm which is plenty for the typical stepped mono1 but the DF26 may take a little more pushing with its flat bottom, assuming that is the case I would go for about 4000kv on 2s or 3200 on 3s which should let you use X435 or 37.5mm graupner/Tenshock.

Americans tend to run lower Kv than we do in Europe with bigger props, I've been told several times on forums that my setups are SAWs only and will burn stuff up when I'm getting 5-6 minutes runtime and low temperatures by running props appropriate to the KV, smaller than they are thinking of. I have posted threads about it, but none have come up with a good explanation of why we run higher KV when we have little power available to us and Americans with many times our power spin their props slower, I can see it for monos where we have steps to loosen things up but its the same for hydros too, best I can come up with is it being a cultural thing like their big torquey V8 mustangs and chevys that used to race our little four banger minis and lotus cortinas in '60s touring car racing.

[British Bulldog]

ok so that makes sense to a degree, please bare with me while i wrap my head around the two different points that have been made.

Paul i will be running in the SWAMBC mono 1 class so yes basically 2s are my limit, had to mod my post its so late i miss read your post, you answered the question i asked many thanks.

Best regards Bulldog

[British Bulldog]

ok so going off whats been said and comparing whats availible pretty much im back where i started with the lepoard 4050kv motor in a 380 case size you can view here.

http://www.astecmodels.co.uk/catalog/product_info.php?cPath=24_114_118&products_id=1260

still requires the 100amp esc.

I can run the 3/16 strut with the 4mm adapter allowing for the use of 4mm bore prop's and i can also use a Octura X435 with a 4mm bore (you can see here)

http://www.prestwich.ndirect.co.uk/octurapropellers.htm

or any matching graupner 37.5mm props of 2s lipos should give me everything i need to at least be competitive in the swambc class.

If this is right ,that was basically my original plan and i wasn't mislead from the original advice given if its not then i think i need to go and do a bit more research to better my understanding.

Regards bulldog. oh and get some sleep cos i will be back tomorrow :D lol

[Basstronics]

So about 1.8KW to push a 26"mono at 38mph, that sounds pretty inefficient, I'd be surprised if bulldog doesn't get at least that speed using < the third of that power he has available to him as a Mono1.

Edit I looked and I was drawing 156A with the 3060 3000KV motor.

Realize that was a cheap 2 pole hobby king motor I paid like $50 for a few years back. Its not a nicer Tacon or Leopard motor. Those motors are also known to be amp hogs. I dont think its characteristic to be that high of amperage if I run a better motor.

Dont go with 1/8 prop shaft. Entirely to small.

With that being said I would suggest:

http://www.astecmodels.co.uk/catalog/product_info.php?cPath=24_114_116&products_id=1186

4S power...
14.8 x 2050 = 30340 rpm

Maybe a Swordfish 200A ESC or a T180. Might get away with a converted Hobbywing 150A also...

Ive been down the 380 sized motors road before in this hull. Have a look:

http://www.youtube.com/watch?v=6YY5m8BphFU

Heres the 156A run @ 37mph (eagle tree data)

http://www.youtube.com/watch?v=cR5GK9YaRLg

[LarrysDrifter]

So, you're a wrestler? I was a fan of yours in the '80's. Jk.

[British Bulldog]

So, you're a wrestler? I was a fan of yours in the '80's. Jk.

lol HULK HOLGAN! rawwww!

ok i'm guessing that there is this argument over motors with different views on what's best which i doubt will ever be solved, Paul is recommending i stick with the original plan of a 4050, Bass you suggesting the larger can but a 3660 that's less amp hungry, so both good suggestions, Bass i have limited options to run of 2s5000mah or 3s 4600mah as the race limits dictate so 4s are out.

So using the 3660kv I'll be using 3s 4600mah, if i used the 4050kv i be using the 2s 5000mah, they would both be using the x435 prop , now to throw my own spanner in the works... it has been noted (from pauls links) that in 2008 many of the setup's used are using the 380 can sizes in the 4000 range of motors with the same prop or similar to what i have suggested to use, as Paul said many have never changed there motors for a few years. So i can only agree with Pauls comments that the European series tend to just run higher kv motors as they prove to be effective.

Just to show what was used a few years ago, and really nothing much has changed a 2008 race setups one member used a feigao 380XL6 with a 70amp esc and a x435 prop,running off 2300mha lipos (assuming that's a 3s, seams a bit small for a 5min race but if its 2s thats pretty good but it is a lower amp draw which could explain it.)

There are a few other examples of similar can sized motors being used so i am more inclined to stick with my original thought of the 4050, Bass don't get me wrong your advice is very much welcome and your prince goes like a bat out of hell, i'm very impressed i just think for the UK mono 1 the 4050 may be best suited.

Best regards bulldog

[Basstronics]

Eh limited by a rule. Thats cool. There are no rules when you just run for fun.. lol

[NativePaul]

I think those 2300s weren't LiPos, but A123 LiFePo4s, there lower voltage than LiPo 3.3v nominal as opposed to 3.7v and you can run them in 3s2p for the 4600mAh you referred to earlier.

If your going 2s I would recommend a 120A ESC, you will be pulling half that on average but the current spikes can be 120A and I have seen plenty of 90A ESCs smoke in Mono1s.

[British Bulldog]

Thanks Paul i think i may do just that 120 is only a few £ more then 100amp so not to worried about the extra if it saves the esc from burning up.

[British Bulldog]

Well the hulls only about 200 miles from me so have enough time to order any outstanding parts, the one question i need to ask is about reinforcement of the hull.

I'm not sure if the hull is an epoxy layup or a polyester layup, i'm hoping it is epoxy which would make life easier, does anyone know exactly what layup the deltaforce delta hull is?

I'm thinking of going with a CF (carbon fiber) reinforced layer on the inside. Any suggestions on what is the best way to go about it?
I've layed up GRP many times in the past 20 years or so, so i know the dribs and drabs when using glass cloths & tissues, but CF is a whole new material I've never worked with.

If the hull is a polyester layup then reinforcement is defiantly needed, if its epoxy its doubtful i will have a need to do so being that epoxy is much stronger. I'm under the impression its a epoxy layup as polyester does tend to shrink during the curing phase (up to 7% in some cases) i can't imagine that hulll's of these types would be built that way?

but to be on the safe side, anyone know a good supplier of CF in small quantity's to do the inside of the hull? i'm thinking of using the west systems epoxy as its binder, but if you have an alternate suggestion i'm open to advice since CF may need a different resin.

Regards Bulldog