The New American ain't! It's now called the ARGO!

[Avaiojet]

Worst electric design to hit SH.

Just ask Alan.

[Alan Resinger]

Charles,
When are you going to get out a really see an electric model?  You are asking for major problems.  You need to get a whole lot of cooling air to the motor and the electronics bay.  Motors get real warm and ESC's don't work when they get hot plus you're going to kill the batteries by getting them hot. Cute front end, but just not functional unless you plan on about 30 second flights.
You just don't seem to pay any attention to all the pictures people post for you.
Alan

[Avaiojet]

Charles,
When are you going to get out a really see an electric model?  You are asking for major problems.  You need to get a whole lot of cooling air to the motor and the electronics bay.  Motors get real warm and ESC's don't work when they get hot plus you're going to kill the batteries by getting them hot. Cute front end, but just not functional unless you plan on about 30 second flights.
You just don't seem to pay any attention to all the pictures people post for you.
Alan

Thanks for the kind reply Alan.  

[Avaiojet]

Charles,
When are you going to get out a really see an electric model?  You are asking for major problems.  You need to get a whole lot of cooling air to the motor and the electronics bay.  Motors get real warm and ESC's don't work when they get hot plus you're going to kill the batteries by getting them hot. Cute front end, but just not functional unless you plan on about 30 second flights.
You just don't seem to pay any attention to all the pictures people post for you.
Alan

Alan

Gee, you didn't find fault with the nose on Mark's Impact?

I really don't see much of a difference. In fact, my battery is in line with the air flow from the scoop. Not many batteries are.

There's also area above the scoop that will draw in air. Tru Turn electric spinner, the backplate is cut for motor cooling. If there's an issue, they have "Turbo" spinners to increase cooling.

Plus I'll have air exit holes, just haven't put them in yet.

Save a couple of grams. 

You got air exit holes on your Crossfire?

[Avaiojet]

You just don't seem to pay any attention to all the pictures people post for you.

Alan,

What kind of a remark is this?

[Gerald Arana]

Charles;

I got an idea! Why don't you put a 1-3/4" spinner (If that is a 2") and have 1/8" of air coming in the front? (or maybe 1-1/2" for 1/4" all around)

Save cutting holes in the fuse.

Just an idea, Jerry

PS: Neat looking ship!

[Avaiojet]

Charles;

I got an idea! Why don't you put a 1-3/4" spinner (If that is a 2") and have 1/8" of air coming in the front? (or maybe 1-1/2" for 1/4" all around)

Save cutting holes in the fuse.

Just an idea, Jerry

PS: Neat looking ship!

Jerry,

I'm going to wait and see what Mark does with his nose. The one on his Impact. He may be using a smaller spinner?

Good idea and I think I've seen that before.

Interested in this spinner? It's 2.25"   

Jerry, thanks for the reply.

Gotta have humor! 

[RC Storick]

The smaller spinner is a good idea. But what needs the most cooling is the ESC. Just a thought.

[Avaiojet]

The smaller spinner is a good idea. But what needs the most cooling is the ESC. Just a thought.

Robert,

What a surprise, and thanks for the reply. 

Please, your thoughts are always welcome and much appreciated. 

You ran a rear fan on one of your ships, how did that work out? I have room for that also if need be. 

Most E models have tight spinners and a scoop underneath, so I gather from the dozens of photos that I see Posted.

Rear exit holes? If done nicely they can "add" to the overall "appearance," even if located around the perimeter of the motor. Do they help?

I was thinking top of the rear hatch and just behind the battery for exit holes. I'll have substantial air going into that scoop, and some above it.

My first "E" model derived from a poorly designed IC model. I'll be happy if it just rolls along the ground on it's own power. 

Thanks again for the reply Robert.

Charles
 

[Mark Scarborough]

Alan

Gee, you didn't find fault with the nose on Mark's Impact?

I really don't see much of a difference. In fact, my battery is in line with the air flow from the scoop. Not many batteries are.

There's also area above the scoop that will draw in air. Tru Turn electric spinner, the backplate is cut for motor cooling. If there's an issue, they have "Turbo" spinners to increase cooling.

Plus I'll have air exit holes, just haven't put them in yet.

Save a couple of grams. 

You got air exit holes on your Crossfire?

Charles,, the pictures I post on my thread, or in general are mine, please do not repost them without asking,, thanks

as to cooling, if you look at mine, you will see that the scoop will open into the front of the battery/esc bay,,  there are cooling outlets on the top of the nose,, the spinner has an axial intake area to let air in, and openings to get air back to the electronics bay,, your intake will put the air into the back of the bay and there is no intake
I think you should also look seriously at the balance of this model, it has a very long nose,, and a short tail,, it appears that it will be very nose heavy,, unless your stab weighs like,, 5 ounces,,

[RC Storick]

The pictures posted on Stunt Hangar are public domain.

[Mark Scarborough]

Robert,, technically yes of course you are correct,,

[Jason Greer]

Charles,
Mark and Alan are simply trying to reinforce the importance of cooling in an electric model. Please take their comments as constructive criticism and not jabs at your model. Designing an effective cooling system is not a trivial task and should be taken very seriously. These guys have a great deal of experience with electrics and are simply trying to help guide you to a successful setup. A bit of time spent now could prevent you from experiencing a thermal shutdown during a maneuver and potentially losing your model.

Jason

[Avaiojet]

Charles,
Mark and Alan are simply trying to reinforce the importance of cooling in an electric model. Please take their comments as constructive criticism and not jabs at your model. Designing an effective cooling system is not a trivial task and should be taken very seriously. These guys have a great deal of experience with electrics and are simply trying to help guide you to a successful setup. A bit of time spent now could prevent you from experiencing a thermal shutdown during a maneuver and potentially losing your model.

Jason

Jason,

You don't know this yet, but that look is the future for electric. It will just take a while to catch on.

Remember who came up with it.  

[Mark Scarborough]

Jason,

You don't know this yet, but that look is the future for electric. It will just take a while to catch on.

Remember who came up with it.  

how right you are Charley, cause it wil be promoted by the people selling electronics for this app,,
people will need to buy lots of new ESC and Motors ,, probably every flight since the will burn up from overheat,,
well excepting the ones who fly in Alaska,,

[Avaiojet]

how right you are Charley, cause it wil be promoted by the people selling electronics for this app,,
people will need to buy lots of new ESC and Motors ,, probably every flight since the will burn up from overheat,,
well excepting the ones who fly in Alaska,,

I'll bet I have more cooling space volume in my nameless model than you do with your Impact.

You know I was designing model airplanes when you were still in diapers. 

Just having fun with you Mark. I know you know your stuff.

I will keep all that advice in mind and don't think I don't appreciate it because I do.

Thanks for the reply.

[Wynn Robins]

aside from functionality - the nose looks awesome - reminds me of a model called Stiletto.....think it was some kind of racer...... 

[Avaiojet]

aside from functionality - the nose looks awesome - reminds me of a model called Stiletto.....think it was some kind of racer...... 

Wynn,

What a surprise and thanks for the reply, and the complement.

I'm sure, in fact I'm positive, I won't see any difficulties with the design of this nose as far as creating unwanted heat. I gave that thought.

2.25" spinner with cooling holes in the backplate. That's .25" of more clearance area around the motor than models with triditional 2" spinners. Puts more air area around the motor right out of the gate. And I could add a rear fan as Sparkie did. But it'll be fine.

That scoop, with air exit holes added, will draw out air quite easily.

The battery lays in the scoop so it will get plenty of air flow around it. Batteries shouldn't get hot anyway.

With an exit hole aft of the hatch cover, overkill, I'll be in great shape.

I've seen electric models with less cooling features, stuff crammed and less room and the motors don't over heat.

Thing I have to live with is the battery low on the vertical CG.

Had to work with what I had, an existing model set up for IC.

I'll have more design control over the next one.

Gee, if the model and design was someone else's. I wonder.

Thanks for the reply.

Charles


 

[Avaiojet]

aside from functionality - the nose looks awesome - reminds me of a model called Stiletto.....think it was some kind of racer...... 

Wynn,

I started a Thread on the Stiletto a few years ago. I was going to put a MVVS CL engine in it with an extended shaft, I designed the hollow shaft, pillon and all related parts. No praise, no nice nice, nothing positive from CL la la land. All my efforts where just got shot down as usual, common with "everything" I do.

So, I shelfed the design to build other models. Flite Streak, the Mig-3 and this nameless model.

Short while back I started redesigning the model. "Stiletto Electra," but this time, for electric. Designed the elliptical wing only a short time ago, that was the hold up. I hate doing wings.

All parts and plans are drawn, so there's not much left before I send the parts files off to my laser cutter.
Just some fine tuning left for fit.

And I gotta tell ya, I'm really pleased with the design. You think the nose is long on this model?

Photos are of the extended shaft I designed and the Stiletto racer of which you mention.

[Avaiojet]

You just don't seem to pay any attention to all the pictures people post for you.

Da, well gee!

I must be paying attention to somethin.

I don't remember who Posted this photo or if I stole it off SH, but I used it as a guide for the construction of the nose with this model.

I've seen other noses/mounts on models built the exact same way. EVER SEEN CONSTRUCTION OF A NOSE LIKE THIS BEFORE!!

I'll bet you have. And it ain't rocket science.

Of course I consulted with my favorite expert before I went ahead. Gotta have someone to run this stuff by.

Now, if you come in really really close and take a gooooood look, you will see that my nose ring mount is a bit different.

IT ALLOWS FOR MORE AIR IN THE BEST AREA!!

I'll bet it's just as strong.

[Mark Scarborough]

your mount is a LOT different than those Charles,, from experience,, I do note expect yours to survive,, there is a lot more torque on there than you think,, and with no web to tie the attach points together,, It wont take long to fatigue and fracture that plywood,,

however,, its your airplane,, and as I have said, it wont matter until it does,, the sad part is that repairing it will be catastrophic to the airframe finish,, if you fly it,, and it survives first flight issues,,

have you done a preliminary weight and balance on it yet?

[Avaiojet]

your mount is a LOT different than those Charles,, from experience,, I do note expect yours to survive,, there is a lot more torque on there than you think,, and with no web to tie the attach points together,, It wont take long to fatigue and fracture that plywood,,

however,, its your airplane,, and as I have said, it wont matter until it does,, the sad part is that repairing it will be catastrophic to the airframe finish,, if you fly it,, and it survives first flight issues,,

have you done a preliminary weight and balance on it yet?

Mark,

Thanks for the reply and your concern.

There will be no stress or weakness issues with that mount, I assure you. Believe me, there's plenty of guys that have that exact application.

Balance and weight?

I believe I mentioned that someplace? Not sure.

Thing weighs in at 55.3 + or - onces loaded. Gear, wheels, spinner, 4S 2400 battery, wing tip weight, control surfaces, complete.
Balances .5" in front of the spar.

Probably shouldn't paint it. I think it's maxed in weight for the model size?

Thanks again for the reply.

Did you get your fair share of time with the new one yet?  

Charles

[Jason Greer]

It's also maxed in weight for a 4 cell 2400 mah battery. Depending on your prop choice and line length, I would be careful of over taxing your battery. I would recommend keeping the flight times short until you have a feel for how much of the battery you are consuming. Remember, for longer battery life, you don't want to exceed 80% or about 1900 mah's.  As a comparison, the model I flew last year weighs 53 ounces and it uses a little over 2000 mah from a 5 cell 2700 during a 5 minute 20 second flight. Converting this to 4 cell numbers it would consume about 2500 mah's.

[Avaiojet]

It's also maxed in weight for a 4 cell 2400 mah battery. Depending on your prop choice and line length, I would be careful of over taxing your battery. I would recommend keeping the flight times short until you have a feel for how much of the battery you are consuming. Remember, for longer battery life, you don't want to exceed 80% or about 1900 mah's.  As a comparison, the model I flew last year weighs 53 ounces and it uses a little over 2000 mah from a 5 cell 2700 during a 5 minute 20 second flight. Converting this to 4 cell numbers it would consume about 2500 mah's.

Jason,

Thanks for the reply.

With all due respect, I don't have that level of understanding yet, so I'm at a loss to fully understand of what you speak. I do know about the 80%.

I also know I was told a 4S 2400 pack would be fine with the Cobra 2820/14. So I was told.

You don't think so?

There's plenty of room if I have to make changes.

Thanks again for the reply.

Charles

[Avaiojet]

simply put,
your airplane is heavier than whoever recommended the 2400 pack took into account,,
it will take more power

there will be movement on the motor mount I KNOW this, as I have done what you did and it failed,,but hey, your the expert do it your way,, if you dont fly it it wont matter anyway,, otherwise, I gave you valid info and you ignored it,, the failure point will be when the four tabs break off from fatigue


what Jason says is accurate,

of course, if you are only going to fly it level for sport, then how long it flies is no issue,, as long as you set the timer for shorter flights

Mark,

The mount thickness is 5/16". If it's not fine, then I will say you are right. You're the expert.

Comments without recommendations, or suggestions for cures are pointless.

Just spell it out for me.

You have everything you need, weight and size of model.

I have no idea what it weighs without the electronics, battery and motor.

Motor is only held in with four 3mm screws, that can easily be upgraded, so can the battery.

As an expert what do you suggest.

[Avaiojet]

Dan,

Thanks for the non advice.  

Just kidding.

Thanks for the reply.

Ya know Dan, you have always had a way with words.

You guys are suppose to be "experts". All those words and no solution?

I guess no one has the confidence to just recommend a set-up.

And that's understandable.

I'll be at the field Saturday with modelers who will be very helpful I'm sure. And I'll see a few more electric powered models.

I know the model is heavy for it's size and I can deal with that. I have to.

See what happens with the Cobra 2820/14 and make adjustments from there. I did my research to arrive at that. 

This won't be the first time someone has changed motors, props, etc., for better performance.

Won't be the last either.

As far as my Posting time, if I got more straight answers, I'd be Posting less. 

[Dennis Toth]

Well, lots of input. However, I have seen the ship. It is well built and will be fine for what Charles wants to do with it. If it was going to be used for the PA pattern the battery pack would be a little small and the wing load a little high. For sport flying it is fine. There is lots of room to add more battery for a longer flight time. The motor mount is similar to ones that Tom Morris has been using and selling for several years, works fine. Others have used as little as 1/8 lite ply and it also worked. The nose is stiff and with a normal prop load will have plenty of cooling. I have no extra cooling in my Stuka. My motor is also front mounted close to the spinner and the motor is only warm to the touch at the end of  a full PA flight. We have the equipment to check the amp draw and the temp and lots of props to get the load correct. The 2820 size motor is similar to the E-flite 25, more than enough for even 60 oz. All in all the concerns mentioned are points to check but nothing that is a major problem. This ship is going to fly fine.

Best,     DennisT

[Mark Scarborough]

Well, lots of input. However, I have seen the ship. It is well built and will be fine for what Charles wants to do with it. If it was going to be used for the PA pattern the battery pack would be a little small and the wing load a little high. For sport flying it is fine. There is lots of room to add more battery for a longer flight time. The motor mount is similar to ones that Tom Morris has been using and selling for several years, works fine. Others have used as little as 1/8 lite ply and it also worked. The nose is stiff and with a normal prop load will have plenty of cooling. I have no extra cooling in my Stuka. My motor is also front mounted close to the spinner and the motor is only warm to the touch at the end of  a full PA flight. We have the equipment to check the amp draw and the temp and lots of props to get the load correct. The 2820 size motor is similar to the E-flite 25, more than enough for even 60 oz. All in all the concerns mentioned are points to check but nothing that is a major problem. This ship is going to fly fine.

Best,     DennisT

which I believe were pretty much what I said way back,, not enough to fly pattern,, but flying level,, no prob,, I still have questions and concerns about the mount,, with no web to tie the tabs together,, but hey, not my airpolane,, he asked for ,, and I gave input which he poo pooed,, then told me i had not answered,, so,,

[Dennis Toth]

Like I said, I've seen the model. It is fine, motor mount is solid, not a problem.

Best,          DennisT

[Avaiojet]

Dennis,

Thanks for the reply.

You're to kind and honest.   

Here's the "ARGO" in it's first coat of primer.

Robert's 540 went on like butter. Yeah right. Being outside with a mild wind is an issue. 

S
Here's the ARGO sanded with 360. Even the open bays. I sand everything and will do the masking tape test before more, whatever, is sprayed.

Spot putty. The stuff I purchased is fine but I don't like the color. I'll fix that before the next model.

Anyone want to buy an almost full tube of spot putty for half the price?