FMRR

Hey Bob Paul said we should call you Bobo,hope you don't mine.Glad you are going to make Kentucky.Don't know if your next video will show the fuel pump tray installed or not but hope so.Your videos and all the building post here sure will be helpful when I start mine,Thanks to all.And Paul I never said slats increase lift,I said AOA.If your aerodynamics book has anything on wash out,I'm sure it will be to prevent tip stall.Sounds like you will be at Kentucky so we can finish our conversation there.This blog is about building the F14 not aerodynamics 101.BTW are you a Booster rep? I have not decided on turbines yet,Mark. H F14 gets to Vr fast (off the ground) lol.And if so can you help me out with a pair? And is there a service center here in that US?

FMRR

Bob it was Bill that said we should call you Bobo (lol) not Paul,My bad.And Paul I did say "slats increase lift , AOA and drag." So I see how you got got that Idea My bad again(sorry).I am at work, have been for 12 hr's and trying to see what's going on between breaks.Paul I really like to finish our talk on aerodynamics but just don't want to get to off topic here.Maybe we can start a new blog or finish here if the rest of the guys don't mind.And if there any aerodydnamic exsperts please jump in. So if everybody else is cool with it let's have at it.

FMRR

Hi bob,Just finish watching video#17,Thanks for showing the fuel pump tray position,plenty of room there.You might want to put a "pig tail" on that safty wire.After you twist it cut it 1/2 inch and bend it 180 degrees on itself.That leaves a smooth end exsposed.If you ever have to put your arm down her you wont get cut or snaged on the ends.Well I just got home and going to bed, 8 hr's of sleep I hope.

FMRR

Hi Paul,Did you open your wing yet? are you going to post some pic's ? I just like to see how much glue is there.

bigbaggy

Don't want to get off topic either. I have not opened the wing but have marked it up and will get cracking shortly. Rudi will add some more details regarding his modification either in this thread or start a new one. The only slow down is the spar, Rudi made one heck of a strong spar and I need to aquire some of that stuff.

Keep you posted.

FMRR

Hi Paul, I hope Rudi puts the wing mod details here since its very much on topic.I have address of a company out in cali that can sell you the material in 4x8 sheet in 1/4 3/8 1/2 inch.This could be a good second source to Rudi supplier.Just a basic honeycomb sandwich.Rudi added carbon caps I believe.Going with the one piece spar a big plus.Looks like Rudi slit one spar and filled with hysol to make the bend around the pivot box.I would add a doubler in this area from the box (4 bolts) to the first rib.I'll post the supplier Monday when I'm back in my shop.Did you get a chance to measure the wash out in the wing?I like to know that also and than compare.

FenderBean

I watched Bobs video and he said FEJ can beef up things if you pay extra, anyone know what this would include? Im guessing not since nobody has had it done yet or at least posted about it. I know you probably dont need it just some people would like a piece of mind.

rwwinter

As promised here a detailed description of the wing modification I did on my Tomcat.

First of all, I can't take any resposibility if this modification will work for you. Please check the airworthiness by yourself!

Before opening the wing according to the next photo take your time and read my comments carefully:

When cutting the lower wing skin use a Dremel tool or similiar with a new cutting wheel. Cut ONLY the wing skin and make sure not to cut deep into the rips. Most important is to safe the original spar cap in the vicinity of the yellow circle. Do not cut into the spar cap!!!



After cutting the wing skin us a long, thin and sharp knife to seperate the the lower wing sking from ribs and Spar. I little bit of force can be applied to break the skin loose. Don't bend the skin to much or you will damage it permanently. And don't cut into skin, ribs or spar.





Remove the red marked wood parts with a Dremel. Tungsten carbid bits work best here. Again, DO not cut into the glas of the wing skin!





Leave the unmarked wood in place or the position of the wing pivot will change!!!

Next part will show how to build the spar

Rudi

rwwinter

FEJ F-14 wing mod part 2

Next the new front spar will be manufactured:



The front spar extends between the top and bottwom wing about 1 inch. Make a cardboard template of the new spar. Using the photo above as guideline.

Use 2 or 3 ply prepreg sheets .250 core (I got them fromlancair.sniperdyne.com/inventory.asp but I don't know if they sell smaller parts) to make the spar from. The fiber orientation should be +- 45°

At the angle position cut 1 side of the spar. Don't damage the other side!



Remove the honeycomb in the vicinity of the cut





Heat the side not cut carefully with a heat gun to approximately 100°Celsius. Do not use excessive heat or you will damge the GFK. As soon as it is warm enough you can easily bend the spar



Bend it to the correct angle needed (use your wing as jig.The end of the spar should be about 1 inch between top and bottom skin and touch the wood spar. sand the side of the new spar to have as much area as possible to glue them together later on.

Fill the gap in the new skin with a thick epoxy and microbaloons mix.











After cure use a dremel to remove honeycomb material according to the photos for the carbon caps and sand the spar to fit exactly into position. NO force may be used to position the spar.







Cut balsa to cover the honeycomb to prevent excessive epoxy soaking of the honeycomb and heavy spars. It will also make sure that the carbon rovings stay in position







Prepare the carbon fiber rovings.





Make sure they are at least two inch longer than the spar. I use 10 piece on each side the cap should 3mm high as a MINIMUM and fill the complete gap.

Create the carbon caps according to the video:

[youtube]http://www.youtube.com/watch?v=opZPdX0PEHA[/youtube]

When everything is cured removed the tape sand the spars caps with 80 grit (don't remove to much material) and clean with acetone,

Sand the wing skins in the position of the new spar.

Drill the holes fo the screws. (I used the removed wood pice as a template).

At the position of the screws the honeycomb must beremoved.





Fill the area cleared off honeycomb with a 50-50 mixture of cotton flox and microbaloons and epoxy. There are now two possibilities. First let it cure and drill again. Second put the screws through the wet mixture and bolt the spar into position without bolting to hard. Remove the bolts when the mixture is hard but not cured or you could be in trouble and unable to remove the screws.




More will follow later

Rudi

FMRR

Rudi,That is a very well done primary structure modification.Two things I would have considered, would be to add a doubler over the slit and filled fwd spar facing.From the 4 bolts(pivot box) across between the rip stations.Second would be to slit the out board aft spar were it meets the fwd spar at rib station 3,Then you have 100% contact.May be over kill but just my thoughts.I just like to say thanks to you again,Bobo and others.Rudi you are a great builder and pilot.A rare combination.Thanks for keeping it all honest and real. The the pain and glory you shared with us all.Well done.

FMRR

Here is a second source suppler for the materials needed for this mod or anything else you can dream up : /www.generalveneer.com/

General Veneer Mfg Inc
8652 Otis street
South Gate,California 90280

FMRR

HELLO Bob,Drama free Bobo....Just finished watching all your vids up to date.LMAO when you said "move over Opra Bob in the house".I know your busy and burning that mid night oil..don't know how you do it,Great work.We are all on the edge of our seats to see her finish and the test flight.This time next week Kentucky baby oh ya.

1/2 time show

My Feedback: (78)

are you sure you got the Date right ant it 2 weeks away

bigbaggy

Got my skins off, suggest you work the pivot point area loose first then go out board. Use a heat gun and warm up the glue that attaches skins too spars.
Thanks a million Rudi. FEJ should send you a reward, hint hint.

FMRR

How's T minus 12 days 10 hr's 30 sec LOL Just can't get here fast enough.(July 3-9)

FMRR

bigbaggy,Well how does it look iinside, Got Pic's ?

1/2 time show

My Feedback: (78)

I take they was glued well as he said where to start and work out ( heat the glue) sounds like they was stuck!

bigbaggy

Gents no pics worth posting. My wing is exactly like the inside of Rudis undamaged wing.
I can see why it failed. The main spar is glued to a plywood rib outboard edge of the PP. There is no way it can transfer much load spar or skins.

If FEJ rotated the pivot point 20 or so degrees they could do Rudi's mod without having a bend in the spar. Then it would be factory right.
Glad I didn't take to the skies with the current design.

FMRR

Bob good point,Like to see how much glue is at the spar and pivot box.I'm not concern at this point.Mine are going back to the factory and will be certified.I have the time to do this since I will not get to my project untill this winter(bummer).so thanks to you guy's for the heads up. James and FEJ have been great to me.I am also receiving a set of the pivot blocks so I can build my own wings complete.Not that I don't trust the factory,I just want to have the full span spoliers and slats.And dial in a little wash out.If I ever sell her (which i'm not) There will be a pair of factory cert wings and mine own.That's all there is to it.I say it again,James and the factory have been great,drama free man.

rwwinter

Wing Mod part 3

Romve the new spar from the wing and make sure that upper wing skin and spar caps are sanded with 80 grit (remember don't sand through the glas of the wing skin and don't remove to much carbon of the spar) and cleaned with acetone.

Sand the bottom skin and the original spar in the area of the end of the new spar too. (New spar will be inserted between bottom and upper skin about 1inch.

Use a brush to wet the wing skin in the area of the new spar and the carbon spar cap with epoxy. Use a paper towel to remove most of the the epoxy. The intention is to have completely wetted area, but as dry as possible since epoxy is only weight and not strength.

Mix a batch of thick epoxy and 100% flox. Use this mixture to glue the spar in place. Make sure that sufficient flox is between old and new spar and the skins too. Use your finger or a tongue depressor to make a nice radius of flox between spar and wing skin. Use the 4 screws to fix the spar at the wing pivot. Let everything cure.

In the meantime I use carbon fiber to reinforce the removed part of the wing skin like this:



Remove the red marked spar and ribs. It could be neccesary to make some kind of cheater holes to remove the screws... Don't remove too much from ribs just enough that the new spar will fit.

In the area of the green circle remove the balsa between the to carbon caps about 1/2". The new spar will be put between. Use again cardboard to make a template for the rear spar.



Make the rear spar according to the front spar. Check the fit. No force may be used to force it in position.

Sand spar and wing skin clean with acetone.

Wet spar and wing skin with epoxy (see above) and glue the rear spar in place with a 100% flox epoxy mix. Take especiallly care of the joint of the three spars. All three must be perfectly bonded but don't use excessive flox to save weight.

The joint should look like this:



After cure make new ribs out of 1ply honeycomb and glue them with a 50/50 mix of flox and micro in place. Use 100%flox to connect the cutted ends of the wood ribs with the new rear spar. the joint between wood and spar should look like this to have a good connection:



Don't bond the new ribs to the front bottom wing skin in the area of the green circles. We will insert the removed wing skin here when closing the wing.

Make a bonding area for the removed skin in the red area. I used tongue depressors and tape to hold a 1 bid carbon in place during cure. We will use this area for flox when closing the wing.




to be continued...

Rudi

FMRR

[quote]ORIGINAL: bigbaggy


"FEJ rotated the pivot point 20 or so degrees they could do Rudi's mod without having a bend in the spar."

Paul, I think your correct,Simple.

FMRR

Hi Bill,I see Bobo two little helpers arrived lol.

vega406

My Feedback: (73)

yeah good timing while he was filming but he really wanted UPS to come

1/2 time show

My Feedback: (78)

Yeah now Maverick and goose took hot chick pilot to the club. some help they where![:@]

vega406

My Feedback: (73)

if you were couped up in a box for days at Whichita post office what would you do when you get out...DUH thats a no brainer build an F-14