Mark2412

Thanks alot. I think Im just going with Monokote to. I'll wait to get a giant scale before I mess with fiberglass.

Mark2412

What should the diameter of the rivet heads be for this plane?

CaPilot04

My Feedback: (1)

Hi guys/gals:

I am a new builder, I built one trainer 10 years ago and have not built since.  I have recently completed the buildout of my workshop and have started the P51 .60 Scale.  I decided that I wanted to use the E-Flite Electric retracts instead of the pneumatic ones that are called for in the manual.  However I am having some trouble understanding how to adapt the design to utilize these new retracts.  I can post pictures or anything else needed if someone is willing to help me out here.  Has anyone on this thread actually used the electric retracts that could possibly send me pictures of how you modifed the gear framing in the wing.

Thanks in advance and I am looking for to moving forward on this kit.  There is so much information in this thread already it should be in an ebook hehehe.

Looking forward to hearing your comments / requests.

capriman

Mark 2412, Topflite makes a template that will fill your needs, it is part number TOPR2187 and they also have a panel line pen under number TOPQ 2510....hope this helps.

I too am interested in the E-Flight electric retracts. Where is all of the postings of first flights from all the other builders ??

bluetomcat

Hi Guys

I have almost finished the build and I too used the electric retracts. I used the original plans and just popped the retracts in before final finishing of the airframe.
I re-enforced the provided retract rails(which is shown way back in the forum). The airframe is now fibreglassed and painted. I'm just waiting for some extra cash to install some wing servos.
I originally went with the original bell-crank design but I cut the servo wire too short. I now have no access to the wire (inside the wing) so figured I may as well pop in some wing servos too.
I will post some pics soon to show the e-flite retracts. Hopefully they will be strong enough for the overall weight of the airplane. Fingers crossed!

regards
Christian

FallDownGoBoom

My Feedback: (1)

Regarding the E-flite retracts, we have a guy at our field that has a set of them installed in his H9 Jackal. He's happy with them, and the visual impression is pretty positive: they're all metal construction, double set screws to hold in the struts, 3/16 wire, and smooth operation. Installation-wise, they're probably pretty much a drop fit substitution for a Robart/Springair pnuematic. H9 drawings say they're 29mm in height, the Robart 500's are 1-1/8 inch with is 0.5mm thinner. So I'd think you could drop a pair in with no problems.

That said, I'd also keep a couple of things in mind. In his Jackal they work well, but that's a 40 sized plan with short struts and 2.5" wheels. A P-51 is probably going to have 3.25-4.00" wheels, and correspondingly longer struts. Which means there's more mass for the retract to move. There's a thread in one of the forums where a guy drilled out an E-flite retract and used Robostruts in a P-47, and he couldn't get the retract to fully retract. There could be multiple reasons for that (out of alignment trunions, a weak battery, etc.), but if you're contemplating using Robostruts, I'd use 3/16" wire stubs and set screws to attach them to struts. Or I'd check with H9 about warranty support if you drill out the trunions to accept something like a 7/16" Robostrut.

I'd also keep power requirements in mind. Apparently the retracts will pull around 1 amp during their cycle, so you want to make sure your battery is strong enough to handle the load. My friend's retracts wouldn't operate when he first installed them because he was using an older battery. He switched to a newer pack, and all has been well since.

Hope this helps.

RickSide

My kit came in on Friday. Saturday was spent measuring my loft. Sunday spent building a 4'x6' work bench. Tonight I finally get to sit down and start contemplating my build.

Here's my working plan:
- Top Flite P-51 1/7 scale gold edition
- Eflite Power 90
- Phoenix HV-85 ESC
- Eflite 60-120 85 degree retracts
- 6 Hi Tech HS-635HB servos (2x Flap, 2x Alierons (I refuse to use the central aileron with bell cranks), 1x Rudder, 1X Elevator.)
- 2X 5000mAh 4S 30C LiPO
- Covering will be Monocote. Scheme is planned to be Cripes a Mighty 3rd.

I also have spent the past 3 evenings reading through this entire thread and a few others. There are some excellent ideas here that I plan to incorporate and pitfalls I see others have discovered that I hope to avoid.


Build starts this coming weekend (work prevents it starting any sooner).

Hot Rod1956

I to am building a 1/7 scale Top Flight P-51 gold edition kit. I'll be installing a glow engine.(Not sure what size yet). I also have been reading these posts for the last week or so. I have begun construction, but only have assembled the stab. and am starting the fin. I'm most concerned right now about either using the bell cranks or adding the extra weight of another servo. This looks like a big plane and they really emphasize saving weight.

skylarkmk1

HotRod,

I'd opt for the extra servo, the weight difference will be minimal with the elimination of the extra push rods, bell cranks, mounts and larger single servo to move all that stuff and hardware. Benefits are stronger more positive control with less slop, possibly less weight in the wing depending on the servos used. Servo covers can double as the servo mounts and provide easy access. Cons -possibly a larger battery pack depending on the servos used (Digital or Regular). Plan ahead for servo wire guide tubes through the ribs for both the ailerons and Flaps.

raptureboy

There's really no reason to use 2 sevos for the ailerons. The bellcranks have been used for years and are the standard setup for all the TOP Flite warbirds. I use them in my p-47 and they work fine,just make sure you use a lock nut to secure them. To each their own though.

dutchy50

G`Day HotRod.
I to have built and finished my P51 T/F Gold Edition,
Have used the two servo rather than the bellcrank,
Covered whole plane in 3/4 oz Glass then Chrome Monocote as covering.
20cc Petrol engine as powerplant.
All up weight is about 5.5 kilos (12lbs)
Dutchy50

OSUAV8R

To those that have finished their airplane... can you tell us what servos you used?

I have glassed my airplane and am almost ready for paint
using a 1.2 FS engine and Futaba super 8 radio converted with a FRSKY 2.4 module
Century Jet retracts and 4" wheels

dutchy50

I `m using Hitec 5485BB Digital servos throughout my plane.
dutchy50.

OSUAV8R

Why did you decide on that servo?

FallDownGoBoom

My Feedback: (1)

I think you could use just about any "standard" sized servo, with 43 or so inch-oz of torque. I used JR 537's on mine, but there's no reason the Hitech/Futaba/Airtronics equivalents won't work. Whether you use digital or analog servos is more a question of servos you might have sitting in the parts drawer vs. having to buy new ones. The control loads generated at normal flight speed for a P-51 aren't that large. But if you're going to model a Reno racer and fly it at 150 mph, you might want to opt for some high torque digitals.

Mike_Jones

I'm throwing in my hat after spending severl hours reading the entire thread. Phew. Lots of great info here. I want to thank everyone who has contributed and kept this thread going. I will be building this kit this winter. I have already bought everything I need to complete it. I'm going electric. All my planes are electric and this will be no exception. What I have planned is this.
Great Planes Rimfire .80 50-50-500 Outrunner Motor
Castle Creations Phoenix Ice 75 ESC
1) 4000 mah 6 cell lipo
Hobby King HK 15288A BB/MG Servos
Mechanical retracts from Top Flight ARF model
4" light wheels
Cockpit kit from ARF model
Monocoat - Bald Eagle paint scheme modified slightly
Wish me luck.
I'll keep up from time to time on progress.
Mike

capriman

Mike, welcome to the thread and RCU. I too hope to start the plane this winter, but I will be replacing most of the wood with lighter wood, as I have an extensive collection of lumber. If you look hard at the plans, it shows the wing to be set in the fusalage at a positive 1/2 degree incendence, and the stab is set to zero. What the plans don't show is the wing tip washout. The wing is built upside down with jig tabs to set the washout, but that can change when you remove the wing from the board and start sheeting the other side. I contacted the designer and he told me the washout is 2 degrees, so keep that in mind. This is one bird that can make good use of an incendence meter, and some weight saving measures.
I will start my own thread of my build so all of my weight loss methods can be viewed.
Can you post a picture of the bald eagle scheme ??

Neil

Mike_Jones

Hey Neil,
Here is a link to a website with lots of pictures.
http://www.mustangsmustangs.us/p-51/...44-73029.shtml
They have many mustangs there.
Mike

Riddle4U

Yea, I agree...aircraft modelers have been using belcranks for decades, and real planes use pushrods and belcranks. It is of course personal preference, and I didn't want to start a major debate on the topic and get off track. The slop problems can be alleviated with proper hardware selection and implementation. The designers used one servo each for flaps, and belcrank for ailerons. I am sure they had reason. Take two servos taped on to a 1/4 inch hard balsa stick the same length as fuselage center to planned servo location in wing; quickly swing it back and forth 45 degrees each side (two servos because that is the actual total increase in inertia, you could build a longer stick and put one servo on each end and the result is the same). Now do the same with a couple wires taped to simulate the load. It should demonstrate the inertia you add at a distance by adding servos in the wing. It has nothing to do with adding the weight of one additional servo to total weight! It is the inertia of placing the weight of two servos toward the tip! The reason the whole multi servo in the wing concept got started was on large scale aerobatic types where the power and decrease in slop made putting servos in the wing negligible as far as weight and inertia penalty, relative to the very large wing area. Large models of scale aircraft took the cue from the giant aerobats.....and the rest is history. No need on planes of this size, and you actually reduce roll rate for a given deflection by adding weight near the tip! Plus, the hatches are ugly, and you add two more control arms sticking out into the breeze as drag instead of a clean rod coming out with the slip-stream. Just my two cents worth....ya pays yer money and takes yer choice.

raptureboy

[sm=thumbs_up.gif] good info! I was only looking at it from a weight and scale detail point of veiw. If it ain,t broke.....

Mike_Jones

Well the cool weather is here in the North East and I'm back in the basement building again. So far I've got the tail feathers completed according to the instructions. Things went pretty well with that part so it was on to the wings. I'Ve got them almost ready for sheeting now. I changed a few things. I added carbon fiber plates to the main spare from W2 to W5 and to the underside of landiing gear mounts. I work at a factory that manufactures carbon fiber assemblies so I have access to the scrap pile. The plates I'm using are multi ply about .06" thick. It's very light and strong. This stuff cuts very easily using a cut-off wheel with the dremel tool. I'm going to use 1 servo for the mechanical retracts and 1 servo for the flaps. My servos are high torque metal gear. I moved the bellcranks from the alerion position to use for the flaps. This required a little refitting but nothing too serious. I still have to fit in the servo for the retracts. I added a rail between ribs W8 and W9 to support the alerion servos. I'm going to try and add 3 photos to show the wing.
Mike

Mike_Jones

EscapeFlyer

My Feedback: (1)

Your CF mods are a great idea! This should really help.

Brian

capriman

Nice to see this thread is still with us, my plane is still in box form. I wish some of the members here that have finished their planes would check back in and report how the have been flying for them.

nrad2000

I'm planning to get the Top Flite P-51 60-90 Kit from Towers. I have just completed building my first Kit plane - a House of Balsa P-51D Kit# K-40. It went well. I'm planning to maiden it this weekend. For the last 2 years I have flown only ARF's and have done many repairs on my planes. most of them just re-enforcing and periodic maintenance and covering.

Anyway, my question is: Can I use the E-flite 60-120 electric retract for this top flite p-51 kit? I have a 91 4stroke surpass and a 120 4stroke surpass lying around - would the 120 be too heavy?

Any input/suggestions in the build - most appreciated.

Jimmy