Shawn's Shocker

[Chrisg81983]

Kent what iv are your motors again in each configuration

[srislash]

Shawn / kent - Well I would spin them just under 47,000 rpm for my saw passes, but mostly at 32,000 for 4s and 39,000 for 5s. What is the highest you guys spun them ? Thanks for your help

I have had them up near there.I am assuming you are not talking loaded RPM Chris.I've been running 35,000rpm normally.

[nata2run]

Spun mine just over 30k on 6s, if safe she should fly on 8s, will be spinning around the 40k on 8s, Chris 47k sounds like an awfull lot, you would want to be sure you have the right props. You may need to step down to 45 props to be in the safe zones.

[nata2run]

Kent what iv are your motors again in each configuration

Motors are 1370kv ish in wye/star mode on 8s. It don't sound too bad, but simple prop mistakes can be an expensive affair. It still takes a bit to spin 4818/3 at 40k rpm, fair bit more load than x450/3, so maybe start at x447/2 then x450/3 if all good and cool then 4818/3

[lenny]

Hi,
Do you think the problems that people were having with the props,
Could be a malfunction in their helmet ?
Like how you drive the boat and debris in the waters to avoid.
Also if the boat is not setup right or trimmed out right,
The props my not handle that to well.

Just food for thought.

[Chrisg81983]

Kent I already have a set of 447's cut down to 45 for the 6s saw runs, and a standard worked 447 for the 4 & 5 cell

[srislash]

Motors are 1370kv ish in wye/star mode on 8s. It don't sound too bad, but simple prop mistakes can be an expensive affair. It still takes a bit to spin 4818/3 at 40k rpm, fair bit more load than x450/3, so maybe start at x447/2 then x450/3 if all good and cool then 4818/3

Or may I introduce you to http://www.prop-shop.co.uk/index.php...roduct_type=25

[srislash]

Kent I already have a set of 447's cut down to 45 for the 6s saw runs, and a standard worked 447 for the 4 & 5 cell

The cut down ones should be good at 1.45 pitch.

[1945dave]

Looks great Shawn thanks for the link i'm starting to like the fc cnc props might need to get me a few sets. Sme told me when they spun them at high rpm they threw blades. Did u have any problems with them ?

Chris, I doubt a true CNC prop will throw a blade before anyother fabricated prop. In other words I would not trust any prop at the rpm's it would take to shear a CNC prop. I guess someone could do a poor job of designing a prop and have the CNC mill the blades too thin but then I would bet they would bend not shear. I will be watching to see if anyone can prove that concern.

Dave

[nata2run]

I think I'm with Dave on that one!! very good point, although aluminium 7075 is hard, I think coper/b and stainless is much harder. Ofcause when it spins in free ari it dont matter too much, but when it hits the water it gets through a bit of stress. The fact that CNC props can't be as sharp as some steel or copper, could also make a difference.? again, I'm not a rew head and chances of me spinning anything over 40k rpm is not likely.

[Chrisg81983]

Hi,Do you think the problems that people were having with the props,Could be a malfunction in their helmet ?Like how you drive the boat and debris in the waters to avoid.Also if the boat is not setup right or trimmed out right,The props my not handle that to well.Just food for thought.

Lenny the people who had these problems are very knowledgeable people that have tons of experience. I can assure you nothing is wrong with thir heads. Other wise i would not even think of asking the question.

[srislash]

Well I had a great afternoon at my new favourite place to run.With just a few steps I can have a great veiw of the entire lake at elevation.I got to play with props a bit and did find that the boat does handle better with the smaller props( Thanks Keith).
Unfortunately my ET did not record anything so no Speed or amp data.
So let me know what you think http://www.youtube.com/watch?v=aZAJc...=youtube_gdata

[Chrisg81983]

Looking good man !! If I had to say it looks, and sounds like the second run was the best. It just sounded like the motor was spinning easier and at a higher rpm. Hard to say from the video though plus I am watching in my IPad.

[srislash]

Yeah,I still think those 5018's are the trick.These motors just may like the pitch.I guess there is only one way to find out.Get some 52's or 55's and cut them down.

[Chrisg81983]

It can't hurt to try just be careful doing it until u know it's safe to do keep us posted