73" Mystic...1/4" prop options

[keithbradley]

I'm looking for props for my Mystic. Power consists of twin castle 2028s and twin Castle 200HV ICE ESCs. Prop shafts are 1/4".
To those who have had experience with this hull, can this hull handle large props like 6518/3s or 6717/3s? There is of course the option of a x470, but I think I'm going to need a decent amount of pitch to get the speed I want with a 780kv motor.

[Grazacind]

Have you thought of a 4 blade from The Prop Shop.

[keithbradley]

Have you thought of a 4 blade from The Prop Shop.

I'm not sure that I can spin the 65mm 3 blade props without cutting them down...4 blade would surely be too much load.

[Make-a-Wake]

I still vote for the x470's, possibly cut down a hair. What about a pair of 6516/3's if they make them in both rotations?

[keithbradley]

I'm considering these:

http://www.prop-shop.co.uk/index.php?section=store&sub_section=product_detail&id=246&product_type=25

http://www.prop-shop.co.uk/index.php?section=store&sub_section=product_detail&id=250&product_type=25

http://www.prop-shop.co.uk/index.php?section=store&sub_section=product_detail&id=222&product_type=25

[keithbradley]

Alright...

I ordered a set of 65mm 1.6p 2 blade props
and
a set of 67mm 1.7p 2 blade props.

Both are quite large...hopefully my setup can turn them without trouble. I haven't ran a 73" cat yet, so I'm just guessing here. It should be plenty fast with them if the motors/ESCs/hull can handle it! I also considered 60mm 1.7p 3 blades in case these props have a negative effect on handling, but after paying for the 4 2 blades I had to tap out.

[Make-a-Wake]

You bought before I posted(not that you have to wait for me) but I'm glad you didnt get the 60mm's, not enough diameter really, the 6516's should be good....................be careful though, i really think you should try them on 9s2p first though..............just to be safe. You may end up liking that setup...........who knows. Any way to figure total pitch on the 6516's? I'd be curious what they are. I dont know what speedo's you have, but I would recommend at the very least a SF240a hv................and even that scares me a bit, although the load share factor is hard to figure exactly................you seen the new SF300a's???? Bill bought one and will surely share his experience with them when he runs it.

Looking forward to seeing this monster run, you have the hull yet.........????............any pics if so???

[keithbradley]

You bought before I posted(not that you have to wait for me) but I'm glad you didnt get the 60mm's, not enough diameter really, the 6516's should be good....................be careful though, i really think you should try them on 9s2p first though..............just to be safe. You may end up liking that setup...........who knows. Any way to figure total pitch on the 6516's? I'd be curious what they are. I dont know what speedo's you have, but I would recommend at the very least a SF240a hv................and even that scares me a bit, although the load share factor is hard to figure exactly................you seen the new SF300a's???? Bill bought one and will surely share his experience with them when he runs it.

Looking forward to seeing this monster run, you have the hull yet.........????............any pics if so???

I HAD the hull...it's gone for paint now.

I plan on starting with 8s and going up from there. I will have a ton of money into this thing. It's tough when every part you buy costs as much or more than a RTR boat. I will be starting slow with it for sure and getting solid data logged and performance assessed before getting more aggressive. I have reconsidered my starting goal of 100mph also. I'm not saying I won't go 100mph, as I seem to eventually push everything on a long enough timeline, but I'm going to try to stay somewhat mild. It's just not worth crashing a boat like this. 30+ lbs will crash pretty hard. I think 80s is reasonable for keeping the hull on the water and the electronics happy.

ESCs are Castle Ice 200HV. I know the 200 number is lower, but I like the castles and have pushed some of the ICE ESCs well beyond their ratings.

As far as pitch of the props:

6516: 4.09"
6717: 4.43"

Diameter * Pitch ratio = Total pitch

[keithbradley]

[Make-a-Wake]

That is one BIG cat!! You may end up staying with 8s spinnin 6516/3's after you see the amp draw in the log...........200a seem low to you, or are you confident there?

PS - I bet you get this Bad Boy up to 100 eventually, you have 20 hp at your disposal!!!!!!

[keithbradley]

I didn't get any 3 blade props...both sets are 2 blade. I prefer not to create the excess current drain of 3 blade props unless I have to.

I'm as confident with the 200A Castles as I would be with 300A SF ESCs. The shultz 40.334 are monsters...pretty expensive though.

[Make-a-Wake]

I'm as confident with the 200A Castles as I would be with 300A SF ESCs.

Why is that exactly, fill me in here??

[Make-a-Wake]

Not a bad price here:

http://www.ebay.com/itm/130409420760?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1438.l2649

[keithbradley]

Why is that exactly, fill me in here??

I've pushed ICE 160s to nearly 300A without trouble (not a reccomendation, just the truth) and the 300 SF is new and unproven.

[keithbradley]

Not a bad price here:

http://www.ebay.com/itm/130409420760...84.m1438.l2649

Yes, about 1/5 of what I paid. I bought stainless props though, not aluminum. I have had pretty good results with smaller aluminum props...not sure about props with that much area though...