RussF

My Feedback: (4)

Something else to consider is using a smaller prop. Since you will have higher voltage and RPM's using a smaller prop would lower the current demand on the ESC. You could cut down a stock prop to 30 mm or so. Or you could probably use a 32-34mm prop with less pitch. I'm no expert on props but it seems to me the more water they push the harder they work the ESC. The stock prop is 32x55 just for refference.

guver

My Feedback: (325)

Thanks, I was considering a "bigger" prop. I know nothing about boats or props, but it would seem to "gear it up" Haha I tend to overgear my cars and trucks too......

I have a couple of stock props on the way, and will try those on 8 cells. Should be a happy medium between power and top speed... Not too worried about the esc though.

DMehalko

My Feedback: (42)

Ya i tried the props for the reef racer while waiting on the nitro hammer props (had to order these because the ep hammers were not in stock, SAME PROP) and performance decreased big time, wonder how it would do with a bigger prop.


Does anyone know where to get upgraded props fot these boats? I looked at offshore but nothing fits the hammer ep.

David

guver

My Feedback: (325)

pretty coincidital, I just got done measuring reef racer 1.1" hammer 1.2"
I have another prop from a twin motor set-up that's bigger, but I'll only try it with stock 6 cell batt first. I just got my stock prop put on and will try out the 8 cell tommorrow.

DMehalko

My Feedback: (42)

Cool, let us know how it does

guver

My Feedback: (325)

I tried it in a different area (bigger pond) Not very impressed at all. I'm going to check for a bad cell. It seemed sluggish maybe due to extra weight. The esc ran the whole time though , pretty much wide open all the time and the motor stayed cool.

DMehalko

My Feedback: (42)

Hmmm.. I dont think it would get sluggish due to two extra cells, the power should make up for it, anyway i think im going to try the graupner speed 600bb motor and a new esc on 8-10 cells after awhile, but mostly im just trying to find a carbon prop that will fit this boat, im in the process of painting my boat right now ( i got the white one) so i wont be able to try anything new for awhile.

David

DMehalko

My Feedback: (42)

hellomynamisdookie, have you finished your boat yet?

guver

My Feedback: (325)

That's what I thiought, I was quite surprised. Back to the work bench for improvements.

MikDee

Sometimes an ESC will just suck up the extra power, and get hot when its overloaded, especially if its a cheap ESC. I've had this happen with a Traxxas XL-1 esc.

DaGrunt

Any thoughts from anyone on how I might repair a crack between the hull and top portion of port?
I pulled a strong G turn and my nicad slammed into the side of the hull...ouch!
I know its` ABS plastic so fiberglass patch is ruled out
Thanks,
Greg

DMehalko

My Feedback: (42)

Maybe fiberglass the inside? Do you have access to a digital camera? Take a pic and maybe ai can help you out a little more.

David

hellomynameisdookie

In the other thread where you posted the same question, you've got a reply on how to fix it.

guver

My Feedback: (325)

I never even thought of that, I'll try to test the battery or replace it, and retest. I'm having trouble finding places to run the boat. I just read the rules at the metro park and think that I'm not allowed to run it ther.

DMehalko

My Feedback: (42)

Thats too bad, i just moved up from denver, where i used to live in springs, but i now live on a golf corse with a huge lake one block down.

I've decided to try that $9.00 motor and a water cooled esc, i thought about just running more cells but all it will probably do is fry the motor.

Like to here how it performes and maybe some pics of the inside of the boat.


David

hellomynameisdookie

It performs great! MUCH MUCH faster than stock....it rides on the 45k prop down the straights!

Here is the thread I have everything in, pics included.
[link=http://p212.ezboard.com/foffshoreelectricsfrm2.showMessage?topicID=984.top ic]Hammer EP - 700bb direct drive conversion[/link]
Let me know what you think!

hellomynameisdookie

The only thing different from those pics is that I switched over (or under) to a Gundert water pickup. Because I offset the rudder, the rudder water pickup wasn't flowing as much water as I wanted it to through the cooling system. It did flow a little bit of water, but not much.

Since I put the Gundert on, it cools MUCH better.
Ohh yeah, and I also modified the motor mount a little bit from the adice from someone else. The 700bb motor has cooling holes in the front of the motor around the output shaft, and the CEN motor mount is solid so it blocks the holes, stopping a lot of airflow through the motor, not allowing it to cool as good it could. So there are now airflow holes added.

Later,
Bryan

guver

My Feedback: (325)

All those rich people live on golf courses......haha

RussF

My Feedback: (4)

The only carbon fiber prop I've found that might work is the Graupner S series props. They would require some modification, like cutting off the cone and drilling the shaft out and sleeving it to fit the Hammer prop shaft, as well as notching it for the drive dog. I considered it but really I dont know if there would be any worthwhile gains for the amount of cost and work. You could go a bigger diameter and maybe increase your torque but top speed would probably be less and strain on the motor would be higher.

I really think that in order to make this boat faster without heavy mods would be a 600 size motor with a new ESC and 8-10 cells and maybe a nice metal prop like the Octura X435. Thats what I might do some day. Its just hard to mess with it now because I kind of like it as is. But theres always that pursuit of more speed.

DMehalko

My Feedback: (42)

so the octura X435 fits on the stock drive shaft?

RussF

My Feedback: (4)

Dont know for sure but I bet it would work. The shaft on the Hammer is 3mm just slightly smaller than the 1/8" prop shaft size. Should work but I dont know since I've only ever seen a X435 online and not in person. Anyway in looking around it looks like an X632 would be the closest thing to a stock prop that is metal. Its hard to say what is going to work better without trying it. I would like to try them all but at $15 a pop plus sharpening and balancing it would get kind of pricey. I tried the Octura Y534 or Proboat Miss Bud prop. I bought a package of two and tried one at full size and one cut way down smaller than the stock prop. The full size one seemed too big and the boat ran good but you could tell the motor was working hard and it got pretty hot. The small one worked ok but if you pulled the trigger full it would just spin under the water and not really grab. The same thing happened out of the turns. If you were in a pinch you could cut one down to the same size as stock and it should work pretty good. The one problem with the Y534 is the tips flex alot the bigger it is. Conclusion so far ----> The stock one works the best with stock motor and ESC.

hellomynameisdookie

I just happen to have the stock prop shaft and an X435 prop sitting in front of me. The prop fits over the shaft and fits over the drive dog. There is a little bit of play where the prop and drive dog join together, and a tiny bit of play with the prop shaft and the inside of the prop itself... but under any kind of load it would dissapear....but enough play where I don't think it's worth the money.

I don't know if the prop will clear the hull...my Hammer isn't submerged drive anymore.

Here's something interesting I read on another site:
"High lift: a prop which tends to lift the transom when the boat is running.
Low lift: a prop which does not have this tendency.

With Octura props, the X series (an X before the number) indicates a low lift prop. Props without the X are high lift props. "

RussF

My Feedback: (4)

Hey Dookie,
Did you ever actually try that X435 on the stock ESC and motor set up? If so how did it do? Is it balanced and sharpened?

hellomynameisdookie

No, I never did try it. Yes, it's balanced/sharpened. I have the prop because it's the one I use on my rigger.

DMehalko

My Feedback: (42)

Another question, prolly been answered a lot, but this thing takes on quite a bit of water each run, is there anything i can do OTHER than tape the hatch in place?