Official Black Horse 2280mm F4U Corsair thread

[CorsairJock]

Just spent a week fabricating a transport frame for it, will also be used to hold fuselage while I build/ complete it. Frame is made from 3/4" PVC, and a lot of fittings ("Furniture Grade" when possible).
The fuselage cradle will hold it upside down when transporting in my Ram with Lear cover, and hold it upright so I can assemble at the field. Wings are removed from openings on the sides.

[Elbee]

I Can give you precise measurements as measured with my calipers on the 2 degree ones: 0.0400" on the low end, 0.1180 on the thick side. As for the breakaway edges: they serve no purpose for the way I use them as shims for my retracts, and were meant for round motor mounts. It's easy material to work with, yet strong enough to support compression loads that would be imposed on it.

Pics are of the 2 shims for the left wing (ones on right wing already installed), as well as the left wing minus most of the wheel well. With the wheel well partially removed as shown, the wheels still bottomed out/ would not turn, until I added the 2 degree shims. Now it's perfect, just the right amount of clearance, but I'm gonna paint the wheel wells before I install the retract unit.

Offset Plates 1 2 3 Degree STL Files.zip

CJ,

I have attached a zipfile of the design.

This includes 1 each: 1^o, 2^o, and 3^o plates designed in the style of your Ernst Plates.

Dimensions should be accurate outside of 3D printing shrinkage (00.2mm+/-)

It is just as simple to design the STL file for the part the way you will use.

If you don't need the circle or would like to have these rectangles or squares or whatever, let me know.

I was just using your Ernst Shim as a start.

I can do these any way you need the finished shim plate for future work.

Best, LB

[CorsairJock]

CorsairJock,

I remember both the company and the plates from my hobby shop days.

Could you give me the circle line depth or the remaining material height?

As i recall the edges could be cut or snapped off.

Also, if you want the corner and center depressions, what are those diameters and centers relative to the edges?

Here's my take on the 3 degree plate from 'eye-balling' your pictures. Look about right?

Best, LB

I Can give you precise measurements as measured with my calipers on the 2 degree ones: 0.0400" on the low end, 0.1180 on the thick side. As for the breakaway edges: they serve no purpose for the way I use them as shims for my retracts, and were meant for round motor mounts. It's easy material to work with, yet strong enough to support compression loads that would be imposed on it.

Pics are of the 2 shims for the left wing (ones on right wing already installed), as well as the left wing minus most of the wheel well. With the wheel well partially removed as shown, the wheels still bottomed out/ would not turn, until I added the 2 degree shims. Now it's perfect, just the right amount of clearance, but I'm gonna paint the wheel wells before I install the retract unit.

[Elbee]

CorsairJock,

I remember both the company and the plates from my hobby shop days.

Could you give me the circle line depth or the remaining material height?

As i recall the edges could be cut or snapped off.

Also, if you want the corner and center depressions, what are those diameters and centers relative to the edges?

Here's my take on the 3 degree plate from 'eye-balling' your pictures. Look about right?

Best, LB

[CorsairJock]

Hey CJ, Could you post a picture with dimensions of your Ernst Thrust Plate(s)? Pretty easy to replicate in 3DP I would guess. I'll post the STL File back here. Best, LB

These were made by a company called Ernst (the spelling may not be correct), a company which made various accessories for radio control and controline model aircraft. These plates were designed to be sandwiched between a motor mount and the firewall, for the purpose of adding an offset to the thrust line. They came in 2 different sizes, one for larger motor mounts and the other for smaller. Each size came 3 plates to a package, one each 1 degree, 2 degree, and 3 degree.

The ones I have measure 2 1/2" x 2 1/2", and I believe they are the smaller size but not sure ( these were made decades ago, long before there was an abundance of giant scale models).

The one in the picture is a 2 degree plate, with "II" marked on it. I have only 2 degree and 1 degree plates left, my supply of 3 degree plates is gone.

I have used mine more often as plates to alter retract angles, such as I am doing with my Black Horse Corsair. Using them will move the retracted wheels away from the wells slightly, providing needed clearance. This will also result in adding 2 degree forward rake when gear is down, which I don't mind. To use for retracts, I cut a plate such as the one in the pics into 4 strips, then drill out for mounting screws and sandwich between retract and mounting plate in the aircraft.

[Elbee]

[B]
I have a dwindling supply of Ernst Thrust Plates, gonna cut a 2 degree one up and try shimming the retract units.

Hey CJ, Could you post a picture with dimensions of your Ernst Thrust Plate(s)? Pretty easy to replicate in 3DP I would guess. I'll post the STL File back here. Best, LB

[CorsairJock]

Retract Issue: Just trying to out the retracts with Stock wheels mounted, when retracted the wheels are against the wells and the retract unit has about 2 mm gap between it and the mounting plates. If I had bolted it down, it would have tried to push the wheel into the wing, NOT GOOD!
I have a dwindling supply of Ernst Thrust Plates, gonna cut a 2 degree one up and try shimming the retract units. I also may cut away the plastic wheel wells if needed.
Anyone else have this problem?

[CorsairJock]

Just received Black Horse Corsair from Motion RC, THANK YOU MOTION for FAST & FREE SHIPMENT!!!

I have read all the posts here 3 times, I wish I could install Robart 148s but Robart went out of business and they are no longer available (for now at least, but I understand another company has purchased everything and will soon be offering them again?). If anyone has a set they are willing to part with, let me know ASAP, I will pay fair price for the set.

My biggest concern before I begin building it is the flaps: I question having only one flap servo on each wing, actuating the outer most flap which then actuates the inner 2 flaps. It seems to me it would make more sense to have the servo drive the middle / curved flaps, that way there wouldn't be all that stress on the plate which actuates the inner flaps. So my question is: is this stock setup functioning / working well? Or should I consider a modification which has the servo driving the center flap instead?

I plan to build mostly stock for now in order to get her in the air very soon, but eventually want to add main landing gear doors and refinish her with a not so weathered scheme.

I have an Axi 5345/18HD (171KV), Castle Creations Talon 120HV ESC, a pair of 6S 6200 mAh packs, and 3 blade 22 x 10 scale prop for power.

I DO like building scale accurate Corsairs, and like I said it'll be mostly stock for now, but come this winter, ....

I also like to build light, and this looks like the best giant scale Corsair to achieve that.

[CorsairJock]

Thinking about ordering one of these, Motion RC has them in stock. I LOVE the weight, I like to fly light. I've read all the posts, would like to get better retracts but Robart is no longer in Business, so will like stay with stock retracts. Has anyone tried the Dubro 5" scale wheels for fit? That would be my choice if they fit.
Not looking to change much, but I like to hide control rods when I can, especially the rudder. Anybody tried? Ditto elevators.
Already have a 170kv Axi motor that should work, and ESC and a pair of 6S 6000 packs.

[Zantero]

Hello all i have a question about engine sizes between the top rc 93'' corsair and the black horse 90'' corsair, i see a lot of people putting engines as large as the moki 180 in the top rc version while the largest i have seen on the you tube is saito fg90 in the black horse version, im not trying to start a why would you put that large of engine in that plane war just curious on thoughts as to why that is, i know it is a 60cc plane (the black horse version) and it will fly it, there's proof of it on you yube just want some thoughts as to is the toprc version more capable structurally of handling that much power and weight etc etc and the black horse is not, just want to hear some opinions on it, thanks.

[Rod Musgjerd]

Hi everyone! Going to maiden mine this weekend. Doesn’t sound like you guys are using any elevator comp on flaps, is that correct?
Thanks in advance.

[Katniss]

https://www.motionrc.com/products/black-horse-f4u-1d-corsair-2280mm-89-7-wingspan-arf-bhm1000-001

Motionrc

You might also consider the Seagull 87" Corsair
Legenghobby . com or gatorrc .com

[427jimmy]

Are these Corsairs still available in the US? Zigi seems to be out of business?
Thanks for any leads

[TwistedGrin]

Yep never a good feeling learning about Airframe failures of any kind and any kit.....I have often wondered how these Corsairs of "All" kits last with the spar ending at the bend of the wing. Perhaps a 120 with a 6inch prop and rubber isolators on the motor mounts with a cinder block on the tail would indeed work well !!

TG

[kballard72]

Wow - I have over 30flights on mine with no sign of fatigue....but I don't flogg it full blast 90degree vertical or 90degree full throttle bat turns either. Was this a gas powered engine on the failed wing bird? I still proffer the wings are up to task....as far as I know.....no other reports of wing failure in flight.

We do know that MotionRC has repair parts available....not much consolation for a totally destroyed aircraft though

TwistedGrin

We were equally surprised, it was right at the bend where the spar stops, maybe flight 10, experienced pilot.

Was coming out of a turn maybe a 45 bank into the wind.. Perhaps just the right (or wrong) amount of force in a low % failure scenario.

I am not dogging the product by any means. Halfway done with my assembly.. And true only so many Gs balsa can take.

My 120 for it came today, kidding.

[TwistedGrin]

Has anyone reinforced the wing? just watched one rip off right at the bend in a turn. I am currently building mine and considering glassing the bend from the inside.

Or open to other ideas.

Wow - I have over 30flights on mine with no sign of fatigue....but I don't flogg it full blast 90degree vertical or 90degree full throttle bat turns either. Was this a gas powered engine on the failed wing bird? I still proffer the wings are up to task....as far as I know.....no other reports of wing failure in flight.

We do know that MotionRC has repair parts available....not much consolation for a totally destroyed aircraft though

TwistedGrin

[kballard72]

Has anyone reinforced the wing? just watched one rip off right at the bend in a turn. I am currently building mine and considering glassing the bend from the inside.

Or open to other ideas.

[TwistedGrin]

what robart retracts did you use twistedgrin? any pics? yeh,phoenix/ blackhorse models should quit making retracts period, (maybe drop the retail price by $200 and could use that to buy good retracts. i own multiple phoenix warbird models and all need replacement in short matter. this is my first bh model but retracts look almost identical in build process. bending soft aluminum for side plates on retracts = junk/ and the elec motors fall apart. thanks for any help

I stayed with the Electric Retract system
*NOTE: The tailwheel does not need replacement and works with the Robart Controller
**NOTE: The tailwheel may need to be reversed on the controller connection
***NOTE: The tailweel actuator three stage output screw may need lubricating, easily binds up when obstructed

Robart 148E 1/5th scale 90degree:

https://robart.com/collections/retracts-by-aircraft-weight-12-24lbs-rotating-electric

You will also need the retract controller board and extensions/connectors: 2s LiPo power

https://robart.com/collections/electric-retract-accessories/products/copy-of-177-electric-retract-control-unit

https://robart.com/collections/retracts-by-aircraft-weight-12-24lbs-rotating-electric/products/177e-locking-actuator-extensions

30flights now on the Robart system - I did have two Robart retract actuators fail.....the replacements have about 25flights with zero issues

TwistedGrin

[froghunter641]

what robart retracts did you use twistedgrin? any pics? yeh,phoenix/ blackhorse models should quit making retracts period, (maybe drop the retail price by $200 and could use that to buy good retracts. i own multiple phoenix warbird models and all need replacement in short matter. this is my first bh model but retracts look almost identical in build process. bending soft aluminum for side plates on retracts = junk/ and the elec motors fall apart. thanks for any help

[TwistedGrin]

Thanx twisted plenty speed their

Yep but please take note.....I think this aircraft's inflight fire was caused by a LiPo flight battery failure.....possibly due to prop amp overloading.

After repairing the FireBall I propped down to an XOAR 22x12 which still has gobs of power....Wonderfully balanced and quiet performing R/C....I have standing offers to sell it each time I fly it.

Having said all of this - the fire melted everything...so a positive identification of exactly what caught fire first was not possible. Since I had full control of the burning bird in flight and after landing.....I am surmizing one of the two flight batteries had over heated and popped off.....either flew it too long or it got too hot from amp load....or Both !!

Respect the power train - Find the amp load and set up Prop-motor-ESC within electronics specification
Fly in your numbers - don't fly the LiPo down to the red zone (Below 3.7v per cell)
Check your Batteries - Always Balance Charge
Check your power connectors - look for arching or color disfiguration
Set up landing at projected 3.8v per cell
Ensure your field has fire extinguishers on hand
Pre inspect and Post inspect every flight


TwistedGrin