aps f4u

I just finished up on my RB tonight, and it weighed in at only 10 pounds! I figured it would be 11 1/2 to 12 pounds atleast.

I have the Robart 605's installed, and a ST 2300 for a power house, and put the battery pack in it's intended place, and it balanced out (retracts down) with a slight tip to the nose.

Just to be sure my scales were correct, I weighed a 10 pound dumbell, and it's dead nuts!

I will fly the RB this weekend with the company of the local law enforcement with there hand held radar to see if I cant get it to 110 mph, or atleast beat my Shoestrings top speed!

A

Vampire

My Feedback: (2)

aps f4u

Best of luck with your test hop.

Let us know how it goes.

Please advise as to your Prop selection and RPM's w/ your ST-2300

BR

aps f4u

I'm running a 16x8 3 blade, and I have an old Heath kit tach and it won't read 3 blades, but my buddy has one I can use this weekend and I will let you know what the rpm's are after it's maiden flight.

A

THESCALEMAN

hi guys

been keeping a keen eye on this bird...as i have one at the moment......just a few things.....first did you have to modify the tail gear ply plate? mine is further back than the picture in the manual shows....not a problem i'll make a new one....it's interesting what engines you are putting in....bigger than 90's....it's a very tail heavy airframe...what do you think you would add using a 90?....1.1/5lb lead? i think i'll be going the supertigre route..2300, have looked at the OS140 but very expensive here in the UK. any other building hick ups? that i should be aware of. i'am doing a review for a UK mag....which will be published in Jan 2005....have used air retracts not the mechanical versions just because you can't get them here at the moment.....plus i prefer air.

all the best

dave

Dave G

My Feedback: (1)

Been watching this thread, and want to keep updated. I've got one of the RB ARFs, but am not going through with the build right now. Shortly though.

Since it has the new graphics, anyone going to a 4 blade set-up? I've also heard comments on the "no flaps". Anyone using their transmitter's "flaperon" function?

Good Luck to all!

hattend

My Feedback: (20)

If anybody is thinking of doing Flaperons on this plane please do yourself a favor...don't try it unless you are 3 mistakes high (ie: way, way, way up there).

Flaperons with the ailerons outboard (barndoor) as this plane has will be washing-in your wing tips. This will cause a pretty good tip stall unless the wing is already washed-out alot.

If you do use flaperons, let us know how it works (or doesn't)

Don

Vampire

My Feedback: (2)

Dave G,

This airplane does not need flaps. I have landed it on grass withonly a 30 ft. ground roll. The wing area is approx. 770 sq. in. +/- and at a final weight of 11# the loading is 32.8 oz./ sq/ft. which is excellent.

cstevec, attached are the pic's I have promissed on the OS-1.60 FX remote needle install into the right fuselage exhaust opening. Works just fine. What you do not see in the attached pic's is I put a T into the fuel supply line just ahead of the filter and ran it to the bottom of the firewall with a plug in it. To fuel, I remove the plug, insert the fueling line and pinch off the tubing from the needle to the carb thru the right fuselage exhasut opening. You could of course install the 3rd tube to the fuel tank for fueling.

BR

Vampire

My Feedback: (2)

2 more pic's

Kerry S.

cstevec

My Feedback: (1)

Looks good Vamp. I am not much of a two stroke man but I had the 1.60 and muffler left over from another project I decided not to do and figured this was the perfect home for it. Consequently I would have never thought of doing that. I am amazed that you don't have fuel metering problems with that but hey, I'll try anything once. Thats what the hobby is all about. Very clean looking and practical install. Any adverse effects?

lord lucan

Vamp..Thx for W/A figures......food for thought ...what does your radio gear instillation look like..is there room to move servo's way forward at all...with new controll transport.....pull/pull's all round maybee..and a Good light .91..

Vampire

My Feedback: (2)

cstevec:

No issues at all with this needle location, I have done this before and since this is a pressurized system, it works very well.

Lord Lucan,

There is plenty of room if you wish to move your servos foward after you raise the fuel tank up. See my previous post.

jfetter

Well, I haven't flown (yet!) but decided to post a few pictures and motor details for anyone interested. Some folks say WHY convert to electric, especially this plane but I think it is a perfect candidate. 1.) The weight is well within the limit for e-power. 2.) The fuse is HUGE inside, making battery mounting a cakewalk. 3.) Of course it is a sweet looking plane too, which makes it even more fun to fly and have folks ask "what engine you got in there?!" only to watch their jaw drop when you tell them it's electric.

Here are some pics of the engine mounting, including a view of the enlarged reciever battery area which has been modified to vent the LiPo packs rather than mount the RX battery.

More to follow...

Jack

jfetter

Here is a better view of the battery tray (made with carbon fiber reinforced sheet). This tray worked out great allowing airflow over the LiPo's to help keep them cool.

More to follow...

Jack

P-51B

My Feedback: (5)

4130/16 by chance?

jfetter

To convert a plane to electric, serious thought needs to be given to changing the batteries. I had a Lexx pattern plane (designed for electric) which had to have the wing removed (4 nylon bolts) each time the battery needed to be changed, not a good design! All the conversions I have done since, have an easy way to change batteries (belly plan works great!) without removing any bolts/screws. Some may wonder whats the difference but when the battery is connected, the motor is "hot", any glitch could cost a finger. Making the bettery tray easy to open makes connecting up very quick right before flight.

Here is how I handled the Rare Bear. The fuse hatch was modified with a wood frame to exactly fit the opening. 2 pins were added to facilitate lining up the hatch and holding it from shear force while 3 BVM jet latches were added to hold the hatch in place. I added the screws because I thought it looked better, they are simply ground off on the other side giving the appearance of a fastener.

I'll post the motor specs next...

Jack

jfetter

P-51B,

Yes, it is an Axi 4130/16. It is rated for models up to 16 pounds (gliders really, sport planes up to 12 pounds according to closer reading). The mount is from Esprit Models (select the front and rear plate for your motor type then order tubes in whatever length you need, sweet!) and the speed controller is a Jeti Advance 77-3. I plan on using the same battery configuration as I have on my current planes, Thunder Power 6S2P (2 x 3S2P 4,200 mAh G2 packs in series) because I believe performance comes more from less weight than battery overkill. If the flight time is less than 10 - 12 minutes, I will move to 6,000 mAh packs but likely stick with 6 in series.

MotoCalc did a great job with the predictions (they match te actual Amp and Watts within 5%), the folks that wrote that little program have done a great job!

Thunder Tiger Rare Bear Electric Conversion:
----------------------------------------------------
>>> Actual Specs <<<
Flying Weight: 153.7 oz. (9.6 pounds)
Motor: Axi 4130/16
Battery: Thunder Power 6S2P
Speed Controller: Jeti 77-3 Advance
Prop: APC 16x10 Electric
Max Current Draw: 58.3 Amps (Measured with Astro Flight Super Whatt Meter)
Max Input Wattage: 1,028 Watts (measured with Astro Flight Super Whatt Meter)
>>> Predicted Flight Specs (MotoCalc)<<<
Motor RPM: 7,001
Static Thrust: 158.9 oz. (9.9 pounds)
Best Rate of Climb: 1,985 ft./min.

So far, very pleased with the conversion, the ARF is extremely well built and the finish is great. I added some epoxy around the horizontal stabilizer joints after reading a post about them ripping off on a maiden flight (gluing the sheeting to the fuse adds more strength than any internal gluing) but have not modified the gear mounts (though I still may) after a few posts about the gear tearing off on first landings. I'll post some flight details after this weekend...

Jack

JohnVH

My Feedback: (38)

Cant say I have ever seen a jaw drop when you say its electric, I have only seen head shaking

Vampire

My Feedback: (2)

This is what makes this sport so interesting.

Very appealing alternative Jack.

What is the final COST for such an E-conversion ?

BR

P-51B

My Feedback: (5)

Axi 4130/16 = $169.00
Thunder power 3S2P 4200 mAH pack =$139.90 x 2 = $279.80

Total =$448.80 for 12 minute flight.

If you want to fly twice in an hour, add another $279.80 for a second set of batteries. More flights than that will require more batteries or several chargers.

jfetter

Your not seeing the right e-conversion then. My World Models Tai Ji 40 probably outperforms the same plane with a 60 in it. When people see it on the ground and hear it electric, they can never get over it...

Jack

jfetter

Vampire,

The Axi 4130/16 sells for $179, the Jeti 77-3 Advance for $189 and the Thunder Power 3S2P 4,200 packs go for $154 each (2 required). Throw in a motor mount, some extra material (battery tray) and you have a grand total of around $750. You do of course need a good LiPo charger (or multiples like I have) and a spare set of battery packs (I have 6) to make it workable (otherwise you do sit and wait)...

Jack

jfetter

P-51B,

Is that a tone of sarcasm I hear in your typing? Many people like myself who have already made a significant investment in batteries, multiple chargers and other electric goodies don't see the cost as you do. I can move a battery from plane to plane in 30 seconds so I don't need more than 6 to give me flights every 20 - 25 minutes on any of my planes.

The truth regarding electric is it really is cheaper per flight than glow but you have to shell out the money up front. Imaging if you purchased a new glow engine and the clerk told you that you had to buy a years fuel up front? That's really all I am doing.

However, after that year, I fly for 6 cents per flight!

Errr, if my plane is still flying, I can only say I am beter at building than I am at flying...

Jack

jfetter

... and typing...

Jack

P-51B

My Feedback: (5)

Yep, its a touch of sarcasm. Right now I am in the park flier stage of electric, but ramping up rapidly to standard size. The Axi 4130/16 is one of the motors I am considering for a conversion.

I am just jumping into the electric thing, and the costs are high. I like the idea and lack of cleanup, but I will have to see if it is really cheaper per flight. If you total a glow plane, you still aren't out $279.00 bucks in batteries, just the 15 ounces of fuel.

Also, if I want to fly a similar number of flights per hour, I would need three sets of batteries, plus two astro 109 type chargers. The Batteries alone would be $420, I can by several years worth of fuel for that, and I haven't seen a good life expectancy estimate on the Lipos yet.

There are pros and cons to each, I want to try both!

lord lucan

Guys ...

Opened the Bear box today ....Wifey has gone to London......when the cats away the mice will....anyway you get my drift...great quallity, this kit seems to have some beefed up L/G blocking..will try to photo later..just weighing everthing...going to look at moveing all the radio as far forwards as practically possible..... not a great deal of wing on this thing so dont want to add too much dead weight ....the spinner and eng mount weigh 1 Lb between them..[:-]...