Shop our Airplanes Products Drone Products Sales
Thread Tools
Old Oct 17, 2012, 06:06 AM
F86_sabre is offline
Find More Posts by F86_sabre
Registered User

Su-25


I am encloseing an excerpt on the SU with some technical details. Hope this may be of interest.
Sign up now
to remove ads between posts
Old Oct 17, 2012, 06:14 AM
F86_sabre is offline
Find More Posts by F86_sabre
Registered User

OOPS...Failed attachment


should be ok now
Old Oct 17, 2012, 05:33 PM
unclecrash is offline
Find More Posts by unclecrash
Registered User
unclecrash's Avatar
Rotesarie Grilled Frogs. Hmmm how much a pound!! LOL looking good I have a fishing rod wrapper that I could use to do that. What you need is a small motor like I have for my rod wrapper its really low rpm you turn it on for putting the epoxy on. It keeps the rod turning so you dont get runs or blobs on one area. It would work great for doing that foam coating stuff. Cabela's sells the rod wrapper they might have the small motors you can buy if you ever decide to try the coating stuff. I agree on the 1inch stations, I can imagine the smaller the model the more critical it would be to do 1inch stations. Im finding with my model being bigger its not too bad sanding. I could imagine if I went 8 or ten foot It would be like doing 1inch stations with my 2 inch spacing only spot I noticed any voids was in the canopy area on mine. Looks sweet Im in need of epoxy going to be a bit before I move on.
Old Oct 17, 2012, 06:49 PM
Maxthrottle is offline
Find More Posts by Maxthrottle
You are a "go" for reentry
Maxthrottle's Avatar
Hey Jumpy;
I had some of the same understanding. Some covered from your thread. May be just the optics from an arm chair view but my eyes are thinking the chamfered stab may need to generate more negative incident for the wing.

I'm concerned as it will be faster than the A-10 that with velocity it will need more trim.
He'll be fine either way.
Old Oct 18, 2012, 11:00 AM
D_FAST is offline
Find More Posts by D_FAST
Registered User
D_FAST's Avatar
Wish i had those drawings and all this info when i was modeling mine. :P

lets hope im ok.

I could use some helpp gathering info on this project.
Old Oct 18, 2012, 11:09 AM
Maxthrottle is offline
Find More Posts by Maxthrottle
You are a "go" for reentry
Maxthrottle's Avatar
Sukhoi posted a lot of line drawings for the frogfoot variants. When they did I copies everything I could find. Not certain of there source use etc other than it beingfrom their site.

Yours looks spot on though.
Old Oct 18, 2012, 05:09 PM
LuvEvolution7 is offline
Find More Posts by LuvEvolution7
Registered User
LuvEvolution7's Avatar
that Russian site is the best for that. can't remember the name for the life of me. I've got tons of drawings from the factory though, including landing gear and all kinds of weird stuff. LOL.
Old Oct 18, 2012, 05:32 PM
CoolerByTheLake is offline
Find More Posts by CoolerByTheLake
Do it Right, the first time!
CoolerByTheLake's Avatar
Not sure if this is the one.

http://www.microsofttranslator.com/b...u%2findex.html

This is the translated one.
Old Oct 18, 2012, 08:16 PM
LuvEvolution7 is offline
Find More Posts by LuvEvolution7
Registered User
LuvEvolution7's Avatar
yup. that's the site.
Old Oct 18, 2012, 08:16 PM
LuvEvolution7 is offline
Find More Posts by LuvEvolution7
Registered User
LuvEvolution7's Avatar
there's another one too. blueprints.com
Old Oct 19, 2012, 10:00 PM
arrowking is offline
Find More Posts by arrowking
Registered User
Are you just using that hand held hot wire cutter? Nice job cutting. It's looking really nice.
Old Oct 20, 2012, 09:29 AM
D_FAST is offline
Find More Posts by D_FAST
Registered User
D_FAST's Avatar
@Arrowking,

Yes, well i still use a band saw and table sander to square up the foam blocks.
Old Oct 20, 2012, 10:41 AM
AirX is offline
Find More Posts by AirX
EDF rules... :)
AirX's Avatar
Quote:
Originally Posted by D_FAST View Post
@Arrowking,

Yes, well i still use a band saw and table sander to square up the foam blocks.
Keith Sparks has the fastest way to square up blanks. I bought his book on foam modeling, he has a few techniques that speed up the process of cutting foam with accuracy.

Cheers,
Eric B.
Old Oct 22, 2012, 09:53 AM
D_FAST is offline
Find More Posts by D_FAST
Registered User
D_FAST's Avatar
Well i pretty much wrapped up the wing construction, but im not sure if i want to use them.

In a rush i noticed the 3mm trace line for my skinning did not print,and i just went with it.
After the structure was laid up, i just stuffed the centers with foam and sanded, they turn'd out heavier then i wanted for starters at 2oz each. with out glass.

Had trouble lining one up into the fus. and to boot these wings just look to small. im starting to worry about the wing loading.

Im thinking i should have increased the chord by 5%and the overall span by about 4% this still would look scale. It most likely would look even better with my slightly enlarged naccles

AUW 40oz @305 sq in wing area =18.9oz sqft
Old Oct 22, 2012, 10:51 AM
Maxthrottle is offline
Find More Posts by Maxthrottle
You are a "go" for reentry
Maxthrottle's Avatar
May be the frog has a faster loiter speed than the A-10 but a better wing load is worth doing.
19 is great actually. Is that 305sq in the enlarged wing?

The A-10 you on the market are likely up around 24 oz/sq in when the wings are to scale.


Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
Build Log EPP SU-39 (modernized SU-25 Frogfoot) formerly: lets play "guess the plane" Mr. UD Foamy EDFs 42 Sep 07, 2015 11:01 AM
Question Ducting for EPP SUKHOI SU-39 (~SU-25 Frogfoot) Mr. UD Scratchbuilt EDFs 8 Oct 15, 2011 01:26 PM
Question Su-25 Frogfoot.... got any plans? birdlives1955 Foamies (Scratchbuilt) 7 Feb 28, 2011 08:28 AM
su-25 frogfoot Robbie d Electric Ducted Fan Jet Talk 7 Dec 03, 2009 11:02 AM