Strake Leading Edges

[gullikson]

Getting ready to purchase some strake leading edges for my Long-EZ. Does anyone know what differences there are, if any, between the Featherlite and AeroCad parts?

[Big Steve]

I have used the featherlight leading edge's they worked great and I really liked them. I know nothing about the other brand. STeve build on

[gullikson]

Thanks Steve!

[Waiter]

I'm not sure about the Aerocad leading edges!

 

I also have the Featherlite and am happy. HOWEVER

 

If I were doing this today, I would make the leading edge straight, ala, Berkut style.

 

The strait edges are a lot easier to make than the original LongEZ leading edges, they had the bend in them.

 

Also, I like the looks of the straight edges vs the bent edges.

 

Waiter

[gullikson]

Yeah Waiter, I have considered this change as well. I need to decide which one I like better. Seems like the straight edges have more room as well.

[EZ AHAB]

I may be adding strake leading edges to my product line if the Girrrls will ever send me the templates for their strake design;) (hint, hint...Chrissi and Randi) I can cut these along with the rest of your order if you want. Of course, these will just be foam cores, not fiberglass.

[gullikson]

EZ AHAB,

 

Cut cores would be great, of course they would need to take into account the laminate thickness so there would be no mismatch, obviously. Are you thinking about making a straight leading edge for the long ez strakes like a Cozy MkIV? I'm giving the MkIV style strakes serious consideration. Mostly looking for a little more room for baggage rather than fuel.

[Big Steve]

I dont think that putting foam cut cores next to where your gasoline is stored is such a great idea. All the foam used in the manufacturing of the strakes is the fuel proof kind. Putting blue wing foam in the leading edge of the strakes is asking for empty glass shells. My .02 STeve build on

[Lynn Erickson]

I dont think that putting foam cut cores next to where your gasoline is stored is such a great idea. All the foam used in the manufacturing of the strakes is the fuel proof kind. Putting blue wing foam in the leading edge of the strakes is asking for empty glass shells. My .02 STeve build on

I have blue foam cores in the leading edge. hot wire cut. been there for 5 years now. if you have a fuel leak in the leading edge you have a bigger problem then the foam being dissolved. the pre made leadings are empty glass shells anyway.

[Big Steve]

Lynn:

 

Glad it works for you. As for me I will not have any foam that is not fuel resistant around my fuel tanks. Steve build on

[EZ AHAB]

if you have a fuel leak in the leading edge you have a bigger problem then the foam being dissolved. the pre made leadings are empty glass shells anyway.

My thoughts exactly. This isn't meant to provide structure, just something to mold the leading edges with. You might as well intentionally disolve the foam out after you get the glass on to save weight.

 

of course they would need to take into account the laminate thickness so there would be no mismatch, obviously.

Well, that depends on whether you've built your strakes already or not. If you have, they will have to be adjusted for proper fit and you will have this problem whether you get fiberglass parts or foam parts except that the foam ones will probably be much easier to adjust. If you haven't yet built your strakes, you just build them to match the leading edges.

 

Are you thinking about making a straight leading edge for the long ez strakes like a Cozy MkIV?

Yes, I suppose you could probably use it for either the Cozy or LEZ although, I make no claims to have done any testing whatsoever. The Girrrls and I discussed providing parts to make their Cozy IV strake leading edge design available while we were at Osh. It's something we just haven't gotten around to yet and had pretty much forgotten about it until I saw your post today. It's just an idea at this point but I think this is how Randi and Chrissi built their Cozy.

[Lynn Erickson]

My thoughts exactly. This isn't meant to provide structure, just something to mold the leading edges with. You might as well intentionally disolve the foam out after you get the glass on to save weight.

 

 

 

Well, that depends on whether you've built your strakes already or not. If you have, they will have to be adjusted for proper fit and you will have this problem whether you get fiberglass parts or foam parts except that the foam ones will probably be much easier to adjust. If you haven't yet built your strakes, you just build them to match the leading edges.

 

 

 

Yes, I suppose you could probably use it for either the Cozy or LEZ although, I make no claims to have done any testing whatsoever. The Girrrls and I discussed providing parts to make their Cozy IV strake leading edge design available while we were at Osh. It's something we just haven't gotten around to yet and had pretty much forgotten about it until I saw your post today. It's just an idea at this point but I think this is how Randi and Chrissi built their Cozy.

I hot wired them to shape with a hole lengthwise down the piece, like the hole in the wing to be used for wire. glued them on, ture up the shape by sanding and glassed over them and move on. I have seen them done with other foam by cutting a v groove, for the wire, in a block of foam, glue them on and shape and glass. after you build the strakes this will seem simple.

[TMann]

Pretty much using the same technique as Lynn. My lines for my brakes and retracts will run in the void between the tank and the foam. As a result, I can run a continous line (no fittings) from the bulkhead in the nose all the way to the end of the strake. The channel that I cut in my sidewall will be the route forward at the point where the strake meets the fuselage.

[Steve Innova]

I don't know if you've already purchased them, but I have the strake leading edges from Featherlight, available for sale.

 

Let me know.

Steve

[Cozy Girrrl]

Oh my god all these hints floating around =)

 

I should read these things more often.

 

First of all, my feeling is if you are concerned about having blue foam near fuel you really need to examine your whole experince and technique with regard to composite construction. This whole idea that the outer skin is somehow your second line of defense for keeping the fuel in the strakes gives me the creeps. Please tell me that BEFORE I get in your plane for a ride, ok?

 

Yes the inner skin might leak because you screwed up and then the foam will turn to mush won't it? So if the foam did not turn to mush that would be okay somehow??? ...and maybe that would be okay because the outer skin might keep the fuel in? Where's the *^%$*^%$ logic behind that one???

 

 

>>> long ensuing discussion for the next week or so on epoxies and coatings, yada yada, horror stories about Chris Barber's experince, yada yada <<<

 

 

Strakes built to plans will more than likely have a leak. Not saying they will or won't , just that the leading edge closure and slit tambour leading edge of skin is really begging for it.

 

Cut the nose off your ribs and put a proper continuous solid leading edge bulkhead on your strakes.

 

We'll send files to Steve for the hotwired leading edges of the strakes and CG strake portion.

 

Fill the tambour slits with very dry micro to hold your leading edge curves, support that curve with your skins on the bench and put 1X very wet bid on the inside of the skin in the tambour zone to strengthen and seal the cuts, then recoat when that one is nearly gone off. Then the slits might not leak.

 

Without the bottom skin on, temporarily put the top skin on and make 2X bid corners from all ris and bulkheads to the top skin from underneath, this is how you make proper T-hat sections that will fit and seal. Trim to one inch each side after you pull the top skin off again.

 

We added a little cabosil to wet flox to prevent it from running and used a lot of it as the "glue" to bond the top skins on.

 

For a full and complete desription either put off your strakes until we publish our strake chapter or catch Randi at any airshow with her Big Book and get her to show you a very detailed description (take some NoDoz first)

 

Thats what we did, your mileage may vary.

...Chrissi & Randi

[Edge 513]

Tambour-ine talk now!!!!

Incredible builders hints these Girrrls come up with...

Now I gotta buy a tambourine to jingle whilst I am working on my strakes.

I'm gonna go find my tie dyed tee-shirt and my old Lp's and put some Strawberry Alarmclock on.

Incense and peppermints... Yea baby;) Where's my paisley forehead scarf?

(Yea, I'm over 50)

[Cozy Girrrl]

Tambour-ine talk now!!!!

Incredible builders hints these Girrrls come up with...

Now I gotta buy a tambourine to jingle whilst I am working on my strakes.

I'm gonna go find my tie dyed tee-shirt and my old Lp's and put some Strawberry Alarmclock on.

Incense and peppermints... Yea baby;) Where's my paisley forehead scarf?

(Yea, I'm over 50)

Listen while I play-ay-ay-ay my greeeeennn tamboreeeeeennn

Oh Edge, lets make music together

[Edge 513]

I'll wear my Peter Fonda costume and ride the American Chopper with the Stars and stripes....See you at the Ashram.

Bring those Kraaaazy anodized spankin' paddles that Ron Springer almost couldn't get past Airport security.

What a Lonnng.... Strange strake it's beeeeen.....

[Cozy Girrrl]

Edge, I think we're just confusing and scaring the young'uns

...Chrissi

[Edge 513]

Edge, I think we're just confusing and scaring the young'uns

...Chrissi

NOT in front of the childrennnnn.....Oh myyy Goshhhh;) :brocolli:

[TMann]

I'll wear my Peter Fonda costume ...

Ah yes, another good Omaha boy.

[steve]

what she said ! thats how i did it. I'll add this, the plans didn't say much about the fuz "from the main spar to the first bag-bulkhead" so i layed-up a X bid lip to match the T-cap already in place and a somewhat screwed lip on the leading edge. if you plan it right you can do the hole job (skins too) without flipping the plane. my skin foam was made from 3/4" strips(idea stolen from cg) from the LE back about a foot so i could get the bend i was looking for. i would install them with pins(1.5" staples) and micro as i went.

once i was back behind the curvy part i installed foam asper plans.

the cool part is now you can remove the hole skin and support it on a table.

glass the inside of the skin,and after it dries ,cover it with duck tape(at the bulk heads) and support it back up under the strake(after you do the lower T-caps), remove and glass the outer skin asper plans, just remember to get it back on and taped fully at the Le. to cure

[CBarber]

One good thing about my little Jeffco/strake, uh.....mishap, is that when I cut the top sections out of the strakes it was well above the seam line. I am not sure how the V/L/Co-Z's do it, but on the Velocity the strakes consist of a top and a bottom strake half. After you install the lower strake "shell" to the bottom of the spar and the fuselage and fit the baffles, you lay the top half on top and weigh it down. A problem area can be were the top and bottom meet at the strake leading edge since it is basicly glued together with a thick and gooy mix of epoxy/flox/micro...what have you. There is no glass on the inside of this seam to bring this together...there is just goo in the seam and then glass on the outside leading edge.

 

Sooooo, since I had access to the back of this un-glassed area at the seam, I was able to add glass and epoxy hopefully all but eliminating this as a area of concern. I hate that I have had to deal with this issue, but am taking this addition as a minor victory none-the-less:cool:

 

It is soooooooooooooooooooooooooo good to feel like I am moving forward again and not just getting back to where I was.

 

All the best,

 

Chris:)

[jpolenek]

First of all, my feeling is if you are concerned about having blue foam near fuel you really need to examine your whole experince and technique with regard to composite construction...

 

Yes the inner skin might leak because you screwed up and then the foam will turn to mush won't it? So if the foam did not turn to mush that would be okay somehow???

I thought that the idea behind keeping blue foam away from fuel tanks was that in the event of a leak, it would still be better to have [fuel-resistant] fuel-soaked foam that's providing support to the fiberglass, than to have a void.

 

Joe Polenek

[Cozy Girrrl]

I thought that the idea behind keeping blue foam away from fuel tanks was that in the event of a leak, it would still be better to have [fuel-resistant] fuel-soaked foam that's providing support to the fiberglass, than to have a void.

 

Joe Polenek

Joe, there's few things wrong with that; first we are only talking about the leading edge, this amounts to little over an inch of foam, second, when you follow our instructions you already have inner and outer plys over the leading edge (urethane) bulkhead before you scab on the round leading edge, and lastly, we're not supposed to have any leaks in the first part.

 

The reason I keep ranting though is somewhere its slid from something like you are saying to "as long as the outer skin contains it" kind of mentality. This is insane nonsense.

It is well known that the two major sources of leaks were due to the poor design of the leading edges per plans and second the tambour slits breaking through the surface. It has been pointed out that the fuel will then travel along the slits and come out through the outer skin somewhere else. Now here is the part that gets me; it is acceptible practice to drain the fuel, apply a small vacuum to the strakes and massage epoxy on the exit point until the leak is sealed. If that is not explicit acceptance of "As long as the outer skin contains it" I do not know what is.