LCHelilover

My Feedback: (15)

HI All, I'm embarking on a new project to build a Focus II as an E pattern plane.

After lurking here and talking to Nat Penton (only local guy with e-pattern experience)- I have gotten a plettenberg 30-10X and Future 32.55K which I will power with two TP 5S4P packs. Having assembled this stuff, I took down the ARC Focus II that was on the shelf as a "backup" and started measuring and thinking.

It was fairly simple to make a new firewall extension box to advance the mounting wall forward enough to positioin the Plet in the nose ring.

Now I'm looking at the battery placement and some arrangement in the belly between the wing tube and the main gear seems to be the only spot that will fit. I'll have to adjust CG with servo and RX battery placement from there....looks like it should be close though. Do you guys with more experience have any thoughts on how to get enough airflow through this "bay" to keep the batteries from overheating? It looks like I can make a channel from the cowl back along the pipe channel and then into this battery area that will be slightly smaller than the battery compartment.

I'm going out to the workshop now to look at prop clearance and see if I have enough room for the 21-22 inch props that is looks like most of you are using with the plett.

I'm thinking about using a small spinner to allow the front of the motor to "breath" rather than covering it up with the backplate...may look a little funkey...I'll have to think about that...any thoughts?

ExFokkerFlyer

My Feedback: (4)

First of all welcome to the dark side!!! Once you fly an electric pattern ship, you'll never go back...

I am finishing up a Focus ARC with an AXI 5330/F3A right now. At first I was planning the same set up as you pretty much. For the motor mounting I got a mount that extended the motor far enough instead of extending the motor box... which I looked at doing but figured the mount with the longer legs would be easier.

For cooling the batteries I planned to bring air into the fuse through the motor box. Specificially, a balsa ramp to direct the airflow up and under the box through a hole (a big one) in the firewall into the fuselage. Remember, now with electric there is no need for such a beefy firewall anymore and most of that can be ground out. I cut a hole in my firewall to match the hole for the fuel tank from inside the fuse. The top of the box will be covered, allowing air to flow through this "S" and cool the batts. You'll also need to cut a large hole in the bottom for the air to exit.

My father is building one as well and is closer than me to being done. Yesterday we put his all together and did an initial weight and balance on it. The weight with an AXI and the TP 5300s came out at 10 lbs. 7 ozs. The only thing left was the spinner and some wires. My guess is it will be at or just under 10 lbs. 9 oz. Now that is with an AXI, with the Plett figure about 4 ounces lighter. Mine is going to be close as my wings were slightly heavier and I am using TP 6000s. Mine will come in just under the wire. That's fine as I will be using 5300s for most of next season anyway.

There have been some efforts to lose some wieght on this airplane. It was easier since they were both ARC, a lot has been cut out of the planes to get the weight down. A new gear block was put in at the bottom of the fuse and tied into the structure that was already there. After it was put in, a lot of the plywood was cut out that was not needed. I wanted to run a 22x12e on this plane without risk of scraping, so this mod added about an inch and a half or so to the overall clearance. That added to the clearance provided by the Bolly electric gear, and I shouldn't have a problem. Take a look at the plane from the standpoint of "what doesn't need to be here". Your vibration is going to be almost nil, no fuel soaking... a lot of un-needed structure can either come out, or be replaced with something lighter.

I have a friend that is also building one of these, but with a Hacker. Our planes will likely be ready in the coming weeks.

Good luck and I think you'll be happy with that combination. I've got a couple of those motors for sale here on RCU in case you know somebody else that might want to take the plunge. Sorry, had to get the plug in there... If there are any other questions you have let me know. I can try to get a couple more pics in the next couple of days if needed.


Here is a pic of the scoop and ESC installation:

PatternPilot

My Feedback: (58)

Hello fellow Focus guys,

Do a search under the normal (glow) pattern area with "focus" and you can see some of my info on my E-Focus that I flew all of 2005 season..
Feel free to contact me direct at [email protected]

Scott Anderson
NSRCA 529 D3 AVP

LCHelilover

My Feedback: (15)

Scott,

I can't seem to figure out how to get the search engine to work...I've tried searching the classic pattern forum for "Focus" and I get no matches....can you direct me to the thread?

Thanks,
G

PatternPilot

My Feedback: (58)

Try this.. if not do a search under pattern.. not the classic ..

http://www.rcuniverse.com/forum/m_30...tm.htm#3096433


Feel free to email me direct at [email protected]

scott

STLPilot

My Feedback: (21)

Hey Pattern your Avatar looks just like my good friends wife. I guess she has a twin sister?

Neo02

Methinks that air is better used over the motor and ESC, batteries in my setup keep very cool throughout each flight (I even closed one air intake to let them build up some heat, as they perform better when warm). Air over the windings is what you need, and a most problematic point with today's outrunners.

Regards,
-Fabrizio

dhooks

My Feedback: (24)

You know Dion we must share a friend ( Imagine that )but unless Im badly mistaken it must be an identical twin to someone he is married to. Maybe triplets....who knows.

PatternPilot

My Feedback: (58)

Hmm

dhooks

My Feedback: (24)

Brain fart?

srg123cohen

My Feedback: (13)

You know this is really strange because a friend of mine has a wife that looks exactly like the one in patterns avatar ALSO.

This is strange

LCHelilover

My Feedback: (15)

I thought I'd give some follow up on the E FocusII project. I finished it and have flown about six flights with it. So far I'm extremely pleased with the power, and flight performance of the Plettenberg 30/10, 10S4P system. with 5 minute flights I'm averaging about 2300 mah recharges on each battery, so I'm going to increase my flight times to 8 minutes and recheck.

I think my revision of the design worked out very well. I had one problem with the gear mount which I needed to re-inforce, but I think I've taken care of that now. I originally converted and kept the onboard lipos and regulator to power the Rx...I've just changed to a UBec--saving about 8 ounces.

ExFokkerFlyer

My Feedback: (4)

Glad to hear it turned out that well! What did your final weight come out to be? What prop and how much draw?

What mods did you make to the plane and you have any pictures?

LCHelilover

My Feedback: (15)

I've tried to upload some photo's of the mod's but I can't seem to get them to the forum here.

Basically I made a recess in the belly forward from the wing tube to the landing gear for the battery packs. The gear was then moved down to the bottom of the fuse. The bottom of the firewall and gear brace are cut out to create a tunnel from the firewall to the battery compartment between the old gear plate and the new gear mounting plate at the bottom of the fuse. The Motor mount had to be extended to move the plettenberg forward to the nose ring. the ESC and wires run through the "tunnel" and the throttle lead and UBEC power run through the battery floor to the rx. I moved the elevator and rudder servos forward to the access hatch under the canopy rather than leaving them under the back of the belly pan. The CG is just about perfect with this arrangement.

I hope the description helps those who might be considering a similar mod. If you would like me to email you some photos I'll be happy to do so...I just can't get them to load to this reply form...

George

[img][/img]
[img][/img]
[img][/img]
[img][/img]
[img][/img]
[img][/img]
[img][/img]
[img][/img]

ExFokkerFlyer

My Feedback: (4)

I would like to see pictures of your conversion George... still have my email address? I'll PM you with it just in case... if you could send some pics that would be great, we can compare notes!

Here is my electric Focus conversion. AXI 5330/F3A, TP 5s3p (x2) 6000, Jeti 90. Weight is right at 11 lbs 4 oz. With the 5300's I should be under maybe by an ounce.

If the graphics look out of focus... that's the point

Adamg-RCU

Best. Graphics. Ever.

ExFokkerFlyer

My Feedback: (4)

Glad you like it Adam. I can't take credit for it, just made the phone call and wrote the check. A guy near me in Visalia, Dick Tristao of Modelgrafix, came up with it for another Focus owner here in District 7, Dick Beldon. I saw Beldon's blurry graphics and I just had to have it! Classic! Just don't have the judges look at it too closely before flight... it really messes with your eyes! Then again, that might actually help my scores... hmmm

Anyway, Mr. Tristao is a good guy and very reasonable... try him at [email protected].

can773

My Feedback: (1)

I also gotta say pretty slick....thought your camera was way out of focus until I made the picture larger

Surefire

My Feedback: (1)

Tom is right! If you look at that graphic too closely before a flight it practically gives you a headache!

Plane looks great Tom!

Jon Carter

farmergregg

Hello, just wondered about the axi, class you fly and your happiness with the performance. I am considering converting my backup Focus II to electric power.

ExFokkerFlyer

My Feedback: (4)

I no longer have the Focus, but will be flying a AXI powered Genesis here shortly. Flew Advanced last year and moving up to Masters this year. The AXI absolutely has enough power... more than you will ever use... great motor.

farmergregg

Thanks a bunch for replying. I am flying advanced after a lengthy layoff. I almost missed the 4 cycle engine phase of pattern, and think I would like to skip it at this point. Just needed a bit of assuance before shelling out the bucks for e power. I will go for it.