JAE Builds

**detox** · 02-10-2010, 03:51 PM

Here's a quote from Rumrunnerracing article

The angle of the strut is even more critical. This is what makes the boat run like a prop riding hydroplane. You will probably want some positive angle in the strut around 1-3 degrees (positive angle is when the back of the strut is lower than the front) Too much positive angle and the transom of the boat will bounce violently on it's tail. Too little positive angle and the back of the boat won't get off of the water. This dragging around the pond is hard on equipment. The motor can't unwind so it overheats and eventually will fail, plus the boat will be dog slow. I always error with a little too much positive angle, it helps the boat get through the corners faster
http://www.rumrunnerracing.com/artic...scalehydro.htm

**Doug Smock** · 02-10-2010, 03:54 PM

Originally Posted by detox

According to UL-1 manual page 7 prop side tilted below centerline is called positive angle.
http://manuals.hobbico.com/aqu/aqub20-manual.pdf

I'll pass that along to my gas, nitro, and FE buds but I don't expect them to change. I hope Aquacraft understands.

At this point with no FE testing, I'm glad we went with Speedmaster.

Back to the shop.

**Chuck E Cheese** · 02-10-2010, 04:30 PM

well that may be what they said on rrr, but i am going to stick with what the designer of the boat told me on the phone (i am pretty sure they tested it). i had been playing with setting up the 12 for a week or so and was happy with how it was running until i followed rods advice of netural on the strut. it made a huge difference in how stabil the boat ran at speed. i originally had 1-4 degrees of positive (back lower) and it was not near as good as netural. also as for bringing up the back end of the boat: in my case and past experience this is something that is done with the prop, not the strut. think of how a mono works. the strut brings the front end down, not the back end up. to bring the back end up you add lift with the trim tabs. to add lift to a rigger (since it doesnt have trim tabs) you add lift to the prop, not push the front lower..

**detox** · 02-10-2010, 04:32 PM

Using a fixed strut is less complicated and relies more on COG to get that correct go fast balance. The adjustable speedmaster will require more attention to detail. I also went with the Speedmaster.

**Chuck E Cheese** · 02-10-2010, 04:44 PM

i have an adjustable strut on my first 12. i will let you know how it goes with the fixed strut on the 12, 21 and FE i am building now...
this forum is great because it lets everyone express their ideas and reasoning

**Doug Smock** · 02-11-2010, 12:51 PM

Heavy sigh

Good luck with your builds guys!!

Doug

**HOTWATER** · 02-11-2010, 01:42 PM

I don't think I am going to worry about any neg. angle being in the strut (sorry Detox...I am also staying with NEGATIVE...)...Jim Mamaril's struts are just fine to use...ecspecially since I will be shooting for a race trim setup...Not a SAW rigger...

Chuck, you are right on target about getting lift out of the prop and shifting weight around the hull to better the CofG...

-Kent

**NativePaul** · 02-11-2010, 05:27 PM

For your information, I ordered one and said I wanted all the hardware to go with it, only specifying that I wanted the inrunner motor mount, it arrived today and has a normal twin bracket fully adjustable strut in the box, whether you chose to call positive negative, negative positive or prefer to use less ambiguous terms, you can run that angle or not if you don't want to on the Zippkits hardware.

**detox** · 02-11-2010, 05:49 PM

Positive or negetive...it does not matter if your boat is faster.

**Chuck E Cheese** · 02-11-2010, 07:52 PM

yes it does mater. if your boat is faster, thats positive.... (think positive, think positive, think positive)

**HOTWATER** · 02-11-2010, 10:35 PM

I won't touch this any farther....I will tell you that I have a Mini Speedmaster strut, A Zippkits strut, one of Jim Mamarils original struts and another one of Jim's newer .21 struts (a little taller and longer than the original w/ 4 crossdrilled holes)..............I have chosen to run the latter of the ones I have listed. I can compare them all I want, side by side, end over end but I am going with my own personal preference here....

You guys are great whether negative or positive!

-Kent

**Chuck E Cheese** · 02-13-2010, 01:40 PM

any more progress on these? i am still waiting on a motor mount to start mine. it should be here today or monday and then i can mock it up and off to paint. i am just curious if anyone has run one yet so i know what to expect. with the ul-1 motor i get 50mph in the hydro and mid 40's in a mogli mono. what kind of speed is expected out of a rigger? i was thinking if i could get 55 and i will be more than happy.

**HOTWATER** · 02-13-2010, 07:42 PM

Originally Posted by Chuck E Cheese

any more progress on these? i am still waiting on a motor mount to start mine. it should be here today or monday and then i can mock it up and off to paint. i am just curious if anyone has run one yet so i know what to expect. with the ul-1 motor i get 50mph in the hydro and mid 40's in a mogli mono. what kind of speed is expected out of a rigger? i was thinking if i could get 55 and i will be more than happy.

Not quite sure what speeds we will get with the UL-1 combo...I would think 55 should be obtainable. What motor mount are you going to be using for your FE JAE?

-Kent

**Doug Smock** · 02-14-2010, 12:00 AM

Originally Posted by Chuck E Cheese

any more progress on these?

I had thrown in the towel on this thread.
We will be testing three of the five builds tomorrow afternoon. Just in time too, our first race is next weekend in Sycamore Ga.

Here are a few pics.

Doug

**Doug Smock** · 02-14-2010, 12:08 AM

A few more.

Trini and Paul both have their boats in paint. They will be ready for action soon.

John, Trini, Paul, Louis, This has been a fun project.

Many thanks to Joe Petro at Zippkits, and Steven here at OSE for hooking us up!!

You guys are the best!!

Doug

**Jeepers** · 02-14-2010, 12:38 AM

Which one is yours?

**Doug Smock** · 02-14-2010, 12:49 AM

The red one. I really hated to put paint on it, the wood looked nice.
This way the guys can see it if, lol, when I'm dead out there.

John's boat is the banana dipped in strawberry.

Doug

**Chilli** · 02-14-2010, 01:14 AM

Beautiful work as always Doug!!! I painted my sponsons and hatch covers red yesterday and now everyone's gonna thinks I'm copying you.

I am going to clear coat the tub and throw a few decals on it. Like you said, that wood is just to pretty to cover up.

Two questions. Are you close to the CG you were shooting for with that lay out and is there a reciever switch installed?

Good luck with the maiden voyage. We're bracing for more snow on Monday. Maybe another 6"....

**Chuck E Cheese** · 02-14-2010, 02:55 AM

nice work smock
i got my hulls from the builder today and he did a sweet job.... i allready have a wood one so i was thinking i was going to paint theese but after seeing davids work i am reconsidering. the FE tub is alot bigger than i expected. there is plenty of room in that one. however, the 21g is wider.

**Scott T** · 02-14-2010, 04:08 AM

They look great Doug! I like the way you've detailed the red/timber one, very nice. I'm really resisting buying one of these, but it's hard!

Interesting treatment on the strut bracket to fit it on the transom. Any chance of a pic of the other side?

**Doug Smock** · 02-14-2010, 07:59 AM

Thanks fellas.
Mike, the CG is dead on 13 1/4", we'll see this afternoon if this is right for the FE version. We really didn't want to shoe horn the esc in the same space as the cells.
The RX is bagged and secured with a velcro strap that is glued to a small piece of 1/8" ply. That assy. is attached to the top of the servo with Velcro. The antenna mount is a 90 degree vac. fitting from pepboys.lol
Scott I'll take a pic of the other side of the hardware today and post it.

Time to charge some cells!

Doug

**jcald2000** · 02-14-2010, 08:34 AM

Doug, how are you going to get the air out of the water jacket, I don't see a water out let on top of the jacket. So the ESC goes on the velcro in the picture not infront by the battery?

**Doug Smock** · 02-14-2010, 10:35 AM

Sorry Jim, I edited the post. The RX is on top of the servo. I'm getting old and tired.

There will probably be some air trapped in the jacket. Hopefully we can get enough cooling with this installation. If not we may have to look at using the smaller diameter (Blue) cooling jacket, getting creative with this one, and or modifying the motor mount. There simply wasn't enough deck clearance to have a fitting at the top, and we really didn't want to do the "S" bend driveline. We thought this was worth a shot.

We'll know more shortly.

Doug

**HOTWATER** · 02-14-2010, 11:39 AM

Originally Posted by D.Smock

Sorry Jim, I edited the post. The RX is on top of the servo. I'm getting old and tired.

There will probably be some air trapped in the jacket. Hopefully we can get enough cooling with this installation. If not we may have to look at using the smaller diameter (Blue) cooling jacket, getting creative with this one, and or modifying the motor mount. There simply wasn't enough deck clearance to have a fitting at the top, and we really didn't want to do the "S" bend driveline. We thought this was worth a shot.

We'll know more shortly.

Doug

Nice, clean build(s) as usual Doug! I really like the boom tube/sponson retainer caps...Nice!!

Good luck with testing...some footage would be great! Also, some runtime #'s, speeds and temps on things would be good to hear about...I know...i'm asking for alot...LOL!

Thanks for the great thread!

-Kent

**detox** · 02-14-2010, 11:47 AM

Doug, I would cut 3/4" off rudder then sharpen rudder blade on opposite side of water pickup port...

Very Nice Builds

...

**Doug Smock** · 02-14-2010, 09:57 PM

Thanks Guys.
We didn't get a bunch of testing in ( our club mates were tuning for the race also) but were able to get a few runs in.
We love the boats, very stable and they corner great. I feel confident we have a good platform to work off of.
7 laps with a 1450 cut down to 44mm, 3.5"cup took 3575 ma. There was no heat today........anywhere.LOL Were're going to be testing some other props next weekend.
I'm working on uploading a video. Here it is http://www.youtube.com/user/sdfe33#p/a/u/0/473lMp--HbM
Keith, I try to land on a prop before I start cutting rudders off. If I take your advice at this point it will leave me with less than 3/8" beneath the prop.

Doug

**HOTWATER** · 02-14-2010, 10:16 PM

Hey!

Thanks for getting a vid out so quick Doug! Mike would like to see this as well! I think the cutdown 1450 works well with the UL-1 setup! Very nice!

-Kent

**Rumdog** · 02-14-2010, 10:16 PM

I'd say that was a successful maiden run!! Very stable!

**Jeepers** · 02-14-2010, 10:21 PM

Very nice Doug!

**jcald2000** · 02-15-2010, 06:17 AM

Doug, it looks like its dragging the ski, add some negetive to the strut.
Great lookin boat!

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