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Old Apr 22, 2009, 03:04 PM
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Fond du Lac, Wisconsin USA
Joined Dec 2007
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Polaris 125

First off, a HUGE



and a Hearty



to Steve for an OUTSTANDING design!! It has to be extremely gratifying to have people from all over the world build and fly your design.


This airplane satisfies a number of criteria I was hoping for:

1.) Motor up high and off the nose

2.) No landing gear - I usually fly off grass

3.) Great high and low speed performance

4.) Ability to fly off grass, snow and H2O

This was my winter build project and I still am not quite done - about 85% complete - just need to hook up the controls and seal it up. I also decided to try a few new ideas to expand my building envelope - 25% bigger size - first time I have upsized a design - airbrushing (my first time), etc...

Here are a few photos of my almost complete build:
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Old Apr 22, 2009, 06:05 PM
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Northwest Ohio
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WOW, the creativity and ideas coming out here are nothing short of amazing!

gocarina, you have been bit hard by the Polarisitis bug! Nice work and vids.

Juggler, you won't have any visibility problems with your bird!

As for me, I am just about done with Polaris # 3. This build has gone extremely well so far.

Scott

www.ModelAero.com
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Old Apr 22, 2009, 06:58 PM
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Northwest Ohio
Joined Jan 2002
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I have the nacelle mounted, and all the linkages hooked up. I chose to extend bullet connectors out the bottom of the nacelle to allow for easy motor swaps. I like to test different motors and this sure beats having to open up the nacelle!

Scott

www.ModelAero.com
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Old Apr 22, 2009, 08:10 PM
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Joined Mar 2009
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the polaris in France FPV

Hello ,
This is a fly in FPV:
polaris (4 min 25 sec)
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Old Apr 22, 2009, 08:12 PM
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Joined May 2004
301 Posts
Motor wires

Hi Guys,

My friend has purchased the Polaris in kit form, and I plan to make one from the plans.

I know this has been discussed many times, but I have to ask. I purchased Steve's F-14 from 6MMRCfoam, and I have my 2200mah battery all the way forward, and the battery leads extended all the way to the back just in front of the Grayson 2212/06 motor with a APC 6 X 4 prop. My speed control is just forward of the motor on the F-14, and located on the outside of the plane for cooling.. This kept my motor lead real short.

This has been working real well for the past year with no problems.

So, I have to ask, why is it that on the Polaris, everyone is saying not to extend the battery leads, but to extend the motor leads?
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Old Apr 22, 2009, 08:35 PM
Retired and Lovin' it!
United States, KY, Sturgis
Joined Jul 2007
2,501 Posts
CptRandy,
My personal opinion is this: if you have something that works for you, do it. I have long leads from the batt to the ESC and long leads from ESC to motor and it has not given me a problem. I also have not had any problems with overheating as many guys posting here have complained about. One thing: I do not push my equipment. I am running a 2212-10 (good power, not great; but also not an amp hog) with a 7x5 APC E prop, a 30 amp Suppo ESC (cheapy) and batts are anywhere from 1500 to 2200 mAh 11.1V. I've been 'dissed' pretty good for saying some of this as if it just couldn't be true, but that's the way it is.

Its a great flying plane and a load of fun to fly. Its a blast doing touch and goes off the grass in my back yard.

Tony
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Old Apr 23, 2009, 12:48 AM
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Seattle, WA
Joined Jun 2002
5,608 Posts
gocarina - Great thinking on the cooling straws.

marie3379 - Nice looking model!

JugglerMike - Wow, that's one of brightest thank you's I've ever gotten! And that's got to be one of the brightest paint schemes I've ever scene, too. You're welcome for the plans. I'm eager to hear how your maiden flight goes.

rotier - Thanks for the video. That's a small pond to fly off of! And welcome to RCGroups!
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Old Apr 23, 2009, 12:53 AM
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Seattle, WA
Joined Jun 2002
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Quote:
Originally Posted by Captainrandy
Hi Guys,

My friend has purchased the Polaris in kit form, and I plan to make one from the plans.

I know this has been discussed many times, but I have to ask. I purchased Steve's F-14 from 6MMRCfoam, and I have my 2200mah battery all the way forward, and the battery leads extended all the way to the back just in front of the Grayson 2212/06 motor with a APC 6 X 4 prop. My speed control is just forward of the motor on the F-14, and located on the outside of the plane for cooling.. This kept my motor lead real short.

This has been working real well for the past year with no problems.

So, I have to ask, why is it that on the Polaris, everyone is saying not to extend the battery leads, but to extend the motor leads?
No worries on asking this question, it's a common and very understandable question. There are several schools of thought on this, but I've tended to side with what Patrick Castillo (owner of Castle Creations and designer of their speed controls) has said, which is that you can extend either side but just don't do either side too much. Generally, he recommends no more than 30" on the battery side and 16" on the motor side, and if you must extend the wires quite a bit upsize the wire gauge to reduce the chance for problems. This advice has worked very well for me. I've attached his actual quote below, which I copied out of a post in the Castle Creations vendor forum:

Quote:
Ok, how about this for a good rule of thumb:

If you are running close to the cell count limits of the controller (absolute cell count limits -- not BEC cell count limits) then its easier on the controller to lengthen the motor wires and not the battery wires.

If you are not running close to the cell count limits of the controller, then it is easier on the controller to lengthen the battery wires and not the motor wires.

Try not to exceed 30" of wire on the battery side, or 16" of wire on the motor side, especially if you are running the controller near its limits.

The reason is this: Lengthening the battery wires increases the resistance between the controller and battery, which increases voltage ripple. When running near the controller voltage limits, this additional voltage ripple can break down the FETs, and eventually cause damage to the controller. Lengthening the motor wires increases the resistance between the controller and motor, which makes it more difficult for the controller to accurately commutate the motor, which increases current ripple, which is harder on the FETs. Longer motor wires also increases the amount of radiated noise in the system more than longer battery wires.

Try not to exceed 30" of wire on the battery side, or 16" of wire on the motor side, especially if you are running the controller near its limits. Also, using heavier gauge wire reduces the effect of longer wires. (for example, using 13ga wire in a 30 amp system with long wire runs would be better than the standard 16ga.)
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Old Apr 23, 2009, 03:13 AM
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Sverige, Västra Götalands Län, Trollhättan
Joined Oct 2006
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My Polaris build starting

I have wanted to build the Polaris since Steve first posted the plans, bud things have not worked out until now. I have converted the PDF-plans to SketchUp and used my Phlatprinter to cut the parts.

I can really recommend the Phlatprinter. Instead of printing plans, cutting plans, laying out the parts on the foam and then finally cutting the foam, I just make the plans in Sketchup (about 1.5 hour work) and then fire up the phlatprinter and let it work it's magic. The cut time for the Polaris parts was about 1.5 hour, during which I messed with other stuff.

I can't top the "thank you" from JugglerMike, but anyhow, a big thanks to Steve for releasing this high quality plan/design for free!!! Great work man!

Updates will follow when I have made more progress.

/Jan
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Old Apr 23, 2009, 05:41 AM
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Manassas, VA
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Hmmm. I don't know. I've been resisting. But it's getting harder and harder to resist ordering that Phlatprinter! -- Tom
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Old Apr 23, 2009, 06:44 AM
Vietnam Vet US NAVY
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Joined May 2004
301 Posts
Wire Length

Tony,

I think you hit the nail on the head. If it works for you, keep doing what you are doing. I do use a larger Ga wire of the best quality. I believe it is silicone covered and very flexible. My run on the F-14 is not close to the 30 inches that Steve has posted.

I'll keep on doing it they way that works, till I have an issue. Thanks for chiming in.

Steve,

Again Thanks for another great model. I love my Tomcat to death. It turns heads whenever I fly it.

That was a great post from Castle on wires lengths. So I guess the fact that I used heavy gauge wire of good quality, and did not exceed the 30 inches, and not running the esc near it's limits, is the reason for my success.

I liked having my esc out in the air for cooling, although on the Polaris, I will have to make it more splash proof or even waterproof if possible. I don't plan on flipping her, ha ha

Let me also add that I read all 106 pages of this thread, before I posted.
Great thread with lots of good info. I'm anxious to start this one.
Thanks to all who participated in this thread
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Last edited by Captainrandy; Apr 23, 2009 at 07:02 AM.
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Old Apr 23, 2009, 07:38 AM
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Sverige, Västra Götalands Län, Trollhättan
Joined Oct 2006
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Quote:
Originally Posted by tessex
Hmmm. I don't know. I've been resisting. But it's getting harder and harder to resist ordering that Phlatprinter! -- Tom
Well, have you seen the MKII version of the Phlatprinter? That cuts foam at least ten times faster than the MK1. Check it out and then put your name on the waitinglist

/Jan
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Old Apr 23, 2009, 08:03 AM
Retired and Lovin' it!
United States, KY, Sturgis
Joined Jul 2007
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CaptainRandy, Steve has it right I think. My leads are long but less than Castle calls for as a maximum. I use 14 gauge speaker wire as that is what I had laying around.

Tony
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Old Apr 23, 2009, 08:23 AM
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Winterswijk, Netherlands
Joined Jun 2007
133 Posts
cooling straws

Hi Gocarina,

That seems like a very good idea with those straws !

Even when it capsizes, the end of the straw (inside the fuselage) will still be above the waterline, so no water will get in, great !

I made a similar construction so I could drain out water that would make it into the bottom compartment through the pushrod tubing, so I could suck it out, but I never thought about using the same principle as a cooling system (i'm just using a piece of pushrod tubing sticking out the top).

Did you make any comparison on just how good the cooling works (like temperature measured inside with and without) ?

The straws are rather small diameter, so not a lot of air will flow, but it's definitely better then nothing.

Simple cooling scoops made out of plastic spoons are ok when on land, but I'm not using them off water. I managed to end up upside down in the water already a few times. A strong crosswind and waves can push over the polaris quite easily, even when stopped in the water. The waves will push one wingtip under, and the wind / waves will then force the whole plane upside down. Also when taking off, waves often will splash over the front of the noze. My scoops would swallow a lot of water just from the splashing, but your straws will not let in more the a few drops.

I might give it a try once my new ESC arrives. Even though thats a 60 Amp ESC, it still could use the cooling.

Good idea ! Thanks for sharing....

Wilco
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Old Apr 23, 2009, 08:34 AM
"It's a Quad" :O
thewz's Avatar
Temecula
Joined Jul 2004
3,179 Posts
Quote:
Originally Posted by kalleman
Well, have you seen the MKII version of the Phlatprinter? That cuts foam at least ten times faster than the MK1. Check it out and then put your name on the waitinglist

/Jan
Or you could get an MK1 and MODD it to MK1.5 like mine. I'm getting 200IPM on the X and Y and 35IPM on the Z. I normally cut at 100IPM or less since the router will melt the foam if too fast.

This is such a good looking plane! Thanks for posting the PDF design.
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