Thread Tools
Jun 09, 2018, 12:53 AM
Registered User
Idea

DIY foamboard Strix goblin


Hi all,
Since shipping is far too expensive for me to get my hands on a Strix goblin, I am gonna try to build one myself, out of foamboard.

I am Using 3 sheets, one for each wing and one for the fuselage. The only difference is that the body will be a lot more boxy, as opposed to the rounded sides of the OG goblin (nose will still be curved though)

I have a few questions already though:


1. Can anyone tell me the dimensions of the fuselage for the goblin? more specifically, the width of it at the front and back, and the height and length of the tail fin? I have no way of getting the measurements.



2. Will laminating it with solarfilm be an option? Does it stick to foamboard? wanting to laminate it for extra speed and rigidity.



3. I am wanting to put in place a full-span aluminium square spar. How would I go about this? As I want the wing to be formed around the square.



4. My power setup is...very beefy to say the least. 2700-3500mah 4s, 6x4 prop, 5200 KV inrunner (yes, fifty-two-hundred RPM/V), and a 120A ESC. Not worried about the electronics, just if the foamboard (wings specifically) will survive the speed? (estimating well over 150mph (around 250-350km/h). I know it sounds a little OP for such a plane with a 1m wingspan, but I'm wanting to see how far I can physically push the foamboard without a catastrophic faliure

Any help is appreciated!
cheers,
Sign up now
to remove ads between posts
Jun 09, 2018, 10:36 PM
IMO ( In My Opinion ) →
balsa or carbon's Avatar
The manual has some illustrations that seem to be about the right proportions :
https://s3.amazonaws.com/content.rea...n+Manual_2.pdf

Just curious .... how much building/flying experience do you have ?
Jun 10, 2018, 08:45 PM
Registered User
Quote:
Originally Posted by balsa or carbon
The manual has some illustrations that seem to be about the right proportions :
https://s3.amazonaws.com/content.rea...n+Manual_2.pdf

Just curious .... how much building/flying experience do you have ?
10 years flying, through 7 planes (3 scratch built, the rest store bought)
Jun 10, 2018, 09:11 PM
IMO ( In My Opinion ) →
balsa or carbon's Avatar
Quote:
Originally Posted by hman123467
10 years flying, through 7 planes (3 scratch built, the rest store bought)
Let us know how it turns out , with video if possible !
Jun 11, 2018, 03:33 AM
Registered User
Quote:
Originally Posted by balsa or carbon
Let us know how it turns out , with video if possible !
Had to do a last minute change to the power system due to availability, only have a 2200kv and a 7x4 on 3s now, while I wait for the previous motor to come back in stock. Should still tip over 100mph though
Jun 11, 2018, 04:40 AM
Wake up, feel pulse, be happy!
Piece's Avatar
Quote:
Originally Posted by hman123467

4. My power setup is...very beefy to say the least. 2700-3500mah 4s, 6x4 prop, 5200 KV inrunner (yes, fifty-two-hundred RPM/V), and a 120A ESC. Not worried about the electronics, just if the foamboard (wings specifically) will survive the speed? (estimating well over 150mph (around 250-350km/h). I know it sounds a little OP for such a plane with a 1m wingspan, but I'm wanting to see how far I can physically push the foamboard without a catastrophic faliure
Dan is that you?

Kv5200 @ 15V = 78,000 RPM no load. Loaded to a practical max of 60% Kv*Vin = 46,800 RPM.

APC E 6x4 requires 493W to reach 23,250 RPM according to Flybrushless data. Doubling that would require 493 x (2^3) = 3,944W, which is 263 amps on 4S.

So your power system might need some rethinking.

150mph with a foamboard airplane is definitely possible, but it'll require a more specialized approach than a typical foamie.
Latest blog entry: Jeti ESC resto-mod
Jun 11, 2018, 12:33 PM
Registered User
Not on the subject of the Goblin. My self-made Nano Goblin.
Jun 11, 2018, 12:57 PM
IMO ( In My Opinion ) →
balsa or carbon's Avatar
Quote:
Originally Posted by gena_g
Not on the subject of the Goblin. My self-made Nano Goblin.
Looks real good !
Do you have a flying video ?
Jun 11, 2018, 05:03 PM
Registered User
Quote:
Originally Posted by balsa or carbon
Looks real good !
Do you have a flying video ?
FlyW (1 min 29 sec)
Jun 11, 2018, 05:34 PM
IMO ( In My Opinion ) →
balsa or carbon's Avatar
Quote:
Originally Posted by gena_g
Excellent , thanks for sharing !
Jun 11, 2018, 07:10 PM
serial scratchbuilder
Granted's Avatar
Quote:
Originally Posted by gena_g
More that a little bit jealous of your flying spot.
Jun 12, 2018, 12:38 AM
Registered User
Quote:
Originally Posted by Piece
Dan is that you?

Kv5200 @ 15V = 78,000 RPM no load. Loaded to a practical max of 60% Kv*Vin = 46,800 RPM.

APC E 6x4 requires 493W to reach 23,250 RPM according to Flybrushless data. Doubling that would require 493 x (2^3) = 3,944W, which is 263 amps on 4S.

So your power system might need some rethinking.

150mph with a foamboard airplane is definitely possible, but it'll require a more specialized approach than a typical foamie.
Yea I rethought that Idea, went down to a 5045 quad prop. hopefully DALprops cyclones will hold up lol. As for the motor, Here is a link to it. I'll see if it'll hold up, be fun either way. The only thing I could be in trouble with is the cooling of it

https://hobbyking.com/en_us/turnigy-...-inrunner.html
Jun 12, 2018, 02:12 AM
Wake up, feel pulse, be happy!
Piece's Avatar
You need to swing a bigger prop if you're hoping to get anywhere near 100mph with the proposed airframe, let alone 150mph.

The F-27C Stryker thread would be a good place to research viable power systems for your model type and performance goals.
Latest blog entry: Jeti ESC resto-mod
Jun 12, 2018, 06:39 AM
Registered User
Quote:
Originally Posted by Piece
You need to swing a bigger prop if you're hoping to get anywhere near 100mph with the proposed airframe, let alone 150mph.

The F-27C Stryker thread would be a good place to research viable power systems for your model type and performance goals.
I am yet to make the wings, maybe keeping the total wingspan below 800-700mm may help with my speed?
Jun 12, 2018, 07:35 AM
Foamy and Glider fanatic
Blacky's Boy's Avatar
Quote:
Originally Posted by Granted
More that a little bit jealous of your flying spot.



HOLY crap yeah!!!!


Are those Migs? You're flying RC planes and quads around an abandoned Airbase!? Wow, how COOL is that?


Quick Reply
Message:

Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
New Product STRIX Goblin - High Performance FPV Wing smoothvirus FPV Aircraft 2785 Yesterday 03:15 PM
New Product STRIX Nano Goblin McSkies FPV Aircraft 3052 Yesterday 06:44 AM
Review ReadyMadeRC STRIX Goblin - RCGroups Video Review Matt Gunn FPV Talk 17 Jan 28, 2018 05:51 AM