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Esser
03-02-2019, 01:41 PM
Apparently the Esser threads continue. I just bought a Model 6 that has been ground looped, ended up on it's back, and in need of repair. This will become my wife plane so I don't have to share:rolleyes:

Looking for any Model 6 nuances. From what I gather the plane is almost the same as the 7 except firewall forward. Would these have the ethanol free tanks? I should be picking up the plane this week and will try to keep everyone in the loop.

So far I know I need:
New windshield
Right strut
Propeller
Prop strike inspection
wing tips
Aluminum header tank
Potentially a new right flapperon
Some wing ribs etc



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jmodguy
03-02-2019, 04:45 PM
I don’t think there is a difference for the 6 or 7 firewall forward... Why do you think they are?

Av8r3400
03-02-2019, 06:58 PM
Wow! Looks like a fun project. Great find!!

896tr
03-02-2019, 07:20 PM
Hey Josh you lucky dog! No the 6 didn't have the ethanol friendly fiberglass tanks I had my wings done when that was discovered.
I intended to slosh the tanks but sold the unfinished kit before I got that far. I heard good and bad about sloshing but if had the chance I would just replace them now. You are in an elite club, The Series "6" club. That was the end of an era. John and Debra went on to better things when they got Kitfox out of the bankruptcy.

rv9ralph
03-02-2019, 07:34 PM
Wow! Great project. I recommend to strip the fabric off the wing to determine any damage not visible from the outside. While at that, strip the other wing and replace tanks to ensure there will be no problem later. Also, on the vertical stabilizer, after stripping off the fabric you can inspect to ensure there is no more damage there.

Just my thoughts.

Have fun with it.

Ralph

David47
03-02-2019, 09:00 PM
Josh, I'd recommend getting the main jigging points from Kitfox - i.e. wing pickup points, MLG pickups, tip of the vertical fin etc. You can then do a mensuration check to see if anything is twisted or not aligned. From reading the fb thread of the guy selling, I understand there's a bend tube above the cockpit - may be a sign of some twist or racking. Hate for you to do a lot of strip down and reconstruct and find you have a twist or other alignment issue that causes some balanced flight issues........ Just my thoughts.

inflight
03-02-2019, 09:25 PM
Josh-

Fun project! You are indeed correct the engine mount was moved a few inches forward in the series 7 to help with CG when filling the baggage compartment. The baggage compartment is slightly smaller in the 6. Actually I think the baggage is the same size but the turtle deck doesn't extend as far rearward. The "swing chicken" as it is called, that bisects the elevator push tube is not there, instead a straight tube from the area of the mixer assembly to the elevator. There should be a shroud on the floor of the baggage compartment to protect the elevator push tube. There isn't a rake from the vertical stabilizer forward on the 6 and the elevator is smaller if that hasn't been updated. The smaller elevator isn't a huge issue if you don't change the firewall forward as the CG is slightly further back. If you do put the longer nose on it then I would absolutely put the bigger elevator on it or you won't be able to get it in to the 3 point attitude on landing with the more forward CG. Also, it most likely has non ethanol tanks (although I wouldn't put ethanol in any kitfox) and the plastic header tank is probably still in it. The rudder is rounded off, not square. On some, the control horns for the rudder are shorter (for a less sensitive rudder) but this causes the rudder cables to rub the fuselage and the linkages to leverage into the rudder. Hard to explain, let me know if you want pictures. Heater? Oil thermostat? Oil reservoir container location? Oil cooler location? Coolant radiator location? Movable rudder pedals? Trim switch is probably different, old design. Main Gear attach hardware probably different. Different flaperon brackets.

What motor is on it? If you are looking to go with a 914 the fit is very tight with the current engine mount. Let me know and I can send you some pictures.

These are the things I can come up with right now. My airplane is currently in Paul Leadabrand's hangar so I can give you some direct comparisons if you need any. Although you have that yourself now with two Kitfoxes. I will let you know if I think of anything else.



-Mark

tracstarr
03-03-2019, 04:26 AM
Sad to see that. That's the plane I was originally trying to buy last winter. I talked extensively with the original owner (actually his brother - the originally owner died before finishing it). The plane was completed by an EAA member somewhere up North there. Hope you got it for a good price and the engine is ok after the prop strike.

I think some of the differences from 6 to 7 depend on when the items were purchased. Mine is a 6 and when I got the FF forward kit in the fall I'm sure I was told it's the same as the 7. Nothing it mounted, so i can always take pics or measurements for you.

Also, I may have an extra flapperon (not sure which side off hand) if you want to take a look. It has a bit of damage to the skin where the hing tore through it from being compressed during travel.

tracstarr
03-03-2019, 04:43 AM
21806

This is what she originally looked like :)

Esser
03-03-2019, 08:27 AM
. I heard good and bad about sloshing but if had the chance I would just replace them now. .
I think since I'll be recovering and painting already, it's a good time to swap them out. I never put ethanol in my tanks but you never know if an accident etc. might happen.


Wow! Great project. I recommend to strip the fabric off the wing to determine any damage not visible from the outside. While at that, strip the other wing and replace tanks to ensure there will be no problem later. Also, on the vertical stabilizer, after stripping off the fabric you can inspect to ensure there is no more damage there.
If the one wing is fine, I'll just cut out the tank area and pop the tank in. The other one I'll probably completely remove. The tail too.


Josh, I'd recommend getting the main jigging points from Kitfox - i.e. wing pickup points, MLG pickups, tip of the vertical fin etc..
I think I have those all in my Super Sport manual but I will be thoroughly checking everything. I actually think the bent tube up top came from him putting his hand on the bar to brace himself as he flipped over, but it for sure warrants further inspection!


Fun project! You are indeed correct the engine mount was moved a few inches forward in the series 7 to help with CG when filling the baggage compartment...

Thanks for all the great information! I'm just mulling over if I want to change the firewall forward now or if it will be fine as is. I'm not a huge fan of the two piece cowl set up. I guess with that swing chicken missing, you can't make an extended baggage area? I will probably enlarge the elevator if it hasn't been already since I'm covering and painting already.

The plastic header tank is in it but I will be replacing that. I think I get what you are saying about the rudder. Is it worth lengthening the horns? To answer the rest of your questions, from pictures it looks like: It has a heater, not sure about oil thermostat but the oil cooler is located just below the prop flange. Oil reservoir is in the center against the firewall. The coolant rad is on an angle mounted to some weird sheet metal baffle just below the engine. Looks like the baffle might actually be the firewall. It has adjustable rudder pedals, and the trim switch looks to be in the same location as my model 7. It has a 912ULS in it.



I think some of the differences from 6 to 7 depend on when the items were purchased. Mine is a 6 and when I got the FF forward kit in the fall I'm sure I was told it's the same as the 7. Nothing it mounted, so i can always take pics or measurements for you.

Also, I may have an extra flapperon (not sure which side off hand) if you want to take a look. It has a bit of damage to the skin where the hinge tore through it from being compressed during travel.
Yes I believe the only make the 7SS FWF now but it bolts on the extact same. The Model 6 was a different design originally. I'm potentially interest in your flapperon! Let me know if it's the right side and how much you think you want for it!


Thanks for the info and questions everyone!

Esser
03-03-2019, 08:31 AM
Here are some more pictures.
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Esser
03-07-2019, 10:13 AM
OK, we picked up the plane and got it home. The plane is in better shape than I hoped. The spars are fine with no dings. The one wing has two bays of trailing edge that need to be replaced, and a few loose false ribs on the outboard end. Really a testament to the strength of this wing. The wing tips COULD be salvage able if you were good at Fiberglass-Reinforced which I'm not...

The rudder tail post is straight and undamaged but the foam tip got all smashed so the fabric still needs to be removed and that fixed.

Right now I'm leaning towards removing ALL the fabric from the wings so I can really inspect the wing and recover. I'm really not looking forward to that process but I think it will be cheap piece of mind.

I definitely need to order a new strut and a new flapper for the right side.

Av8r3400
03-07-2019, 04:02 PM
Gonna put Oratex on the wings?

Esser
03-07-2019, 04:40 PM
Probably not. I’ll probably be recovering the entire plane and I can do that for about half the price of Oratex. Don’t get me wrong. I think it’s a cool product but the fact that some people having issues with it, coupled with the fact that covering is a weak spot for me, I figure I’ll stick with what I know since they don’t have the colour I want anyway!

bbs428
03-08-2019, 09:19 PM
Great find! Glad your not finding it in worse shape. Should be a great plane after you massage the hurts out of it! :D

Esser
03-09-2019, 09:15 PM
Well turns out the one wing was worse than expected. The rear spar bent at the number 5 rib where the I beam starts. I briefly spoke with Brandon and he said it's typically easier to build a whole new wing than replace a spar but it is possible. So I have some things to think about. I am going to call him Monday and talk about my options.

For some reason it wouldn't upload my pictures. I'll try again later.

efwd
03-09-2019, 09:43 PM
shoot, sorry to here that. Kinda a big hit depending on how you look at it. Shoot, you know how to build, I believe you said your wife built with you. Put a little sweat equity into it. Enjoy it.

aviator79
03-11-2019, 01:35 PM
That's a bummer Josh. I'm sure you were prepared for the possibility, but it's still a drag. One way or another I'm sure you'll get her all squared away.

jmodguy
03-11-2019, 04:36 PM
STi wing!!!!

Esser
03-11-2019, 04:41 PM
I'm not sold on the STI wing. By the time you're all said and done, it's probably around $15,000+ and I can fix this for a couple thousand. Plus my plane already has a standard wing so if Nat's plane get's an STI wag then our planes won't have similar performance. I think I am going to play around with leading edge droop cuffs of my own design.



The bent wing is a bummer but I went into this expecting to have to rebuild two wings so anything beyond that is icing on the cake.

avidflyer
03-11-2019, 07:30 PM
I'm sure the factory knows what they are talking about on the amount of work to replace a rear spar verses building an entire wing, but maybe they are figuring it if they were doing the work and charging what ever their shop rate is. I don't count my time as $ so if I was doing it, my concern would be how can I do it so it's good enough and at the same time not spend any more then necessary. What I would do is cut the spar off on each side of each rib, then cut lengthwise through the remaining piece of spar material in each rib and peal it out, using some heat if needed to soften the epoxy. Once all the aluminum spar material is removed, I would clean up the epoxy with a Dremel and slide in the new spar. Of course the drag brace bracket rivets would have to be drilled out to separate them from the spar as well. It's been a long day and maybe I'm missing something else as well, but you get the idea at any rate. Just a guess, but a new spar and aluminum stiffener might be about $300 not including shipping.

aviator79
03-12-2019, 06:13 AM
The wing cuff sounds interesting. Can you do some bolt-on experimentation with C-FOXD before you incorporate it into your "new" wings?

Esser
03-12-2019, 10:27 AM
You pretty much talked about how I exactly plane to move forward Jim. I'm going to remove the tank and then cut the spar in to sections. I can't get a spar from Kitfox until August since the tariffs on aluminum started they've been hard to source. I had someone reach out who has an extra one which was very kind. I'm going to look at building a wing building jig to set everything in to build it true again.

Yeah Brian, I have some friends that made some bolt on cuff out of aluminum for their Ran's and highlanders. I might do something similar at first.

jmodguy
03-12-2019, 11:01 AM
Any idea where the spars are sourced from?

Av8r3400
03-13-2019, 05:52 AM
Honestly, the aluminum tube used for spars is not anything exotic. A friend of mine scratch built his wings and sourced the tube from a local steel supplier (link (http://www.londervillesteel.com/)). He had to buy them in 20' lengths to get the right length, then sold the drops to someone making wing extensions.

jmodguy
03-13-2019, 06:55 AM
My concern with the source is where they are manufactured, not the specific alloy. There are reports of inferior alloys originating in China. 4130 sourced from China has experienced failures where US and German 4130 has not. My own personal experience is with aluminum alloys sourced from China. Although the data sheet for the lot said it was in spec, it did not perform to the spec and was quite different from a US sourced same alloy.

jrevens
03-13-2019, 08:35 AM
I've has the same experience, Jeff. Years ago now, I designed & built/sold (through Aircraft Spruce & others) cabin heat boxes. I used 2" dia. 6061-T6 ( I believe that's the alloy used on the Kitfox spars - might be wrong) for the inlets, & I formed a flange on those. There was variability in not only formability but also weldability between the same material even from different American suppliers, but especially sourced from China. It was junk for my purposes. One can imagine how much more critical it is when we're talking about a wing spar... and one that flexes as much as on a Kitfox makes it even more so.

Av8r3400
03-13-2019, 09:49 AM
You can request and receive material certs for material purchased from any reputable source. This is what Kitfox (and all other manufacturers) do.

jmodguy
03-13-2019, 12:47 PM
I am aware of the certs. Thats how I determined the Chinese aluminum I was using was “in spec” but defective for any practical purpose. All is not what it seems. Especially dealing with some overseas manufacturing.

jiott
03-13-2019, 04:45 PM
I think the key word is "reputable" source.

Esser
03-29-2019, 08:22 AM
So I’ve been slowly picking away. The fabric is removed from one wing and the fuselage. The rear spar has also been relemoved on the damaged wing.

Ive decided to complete convert the fuselage to a Model 7 while everything is open.

2197721978

efwd
03-29-2019, 08:42 AM
Man Josh, I can't imagine diving into another project so soon after finishing yours. Have you finished phase 1 already?

Esser
03-29-2019, 12:36 PM
Yep, finished that about 25 hours ago.

Im not so much diving into it as figuring out what it needs. So far I figure it just needs money! And 200-300 hours of work

coosbo
07-16-2019, 03:18 PM
I guess with that swing chicken missing, you can't make an extended baggage area?
Just wanted to give this question a bump, as I'm also interested to know if you can make an extended baggage area in a 6.

tracstarr
07-16-2019, 03:54 PM
You can. I'm doing it now. It's limited but would allow some sleeping bags.

Sent from my SM-G973W using Tapatalk

Esser
07-16-2019, 04:43 PM
Im not doing his project until the winter but you Definitely can. Requires some cutting and welding

mike92104
08-13-2019, 09:00 PM
Josh, what did you do to remove the adhesive on the wing ribs? I have a damaged one I need to replace.

Esser
08-14-2019, 09:49 AM
Use a heat gun and a flat head screwdriver. You don’t need to really work at it. Once it’s hot enough, it will chunk off easily. After the rib is removed it will be easy to carefully scrape the remnants off with the heat gun. Just becareful not to mark the spar

Esser
08-14-2019, 09:55 AM
If anyone is looking for an update on this project, it’s taken a back burner over the summer. Life is just too busy right now. We will dive back in the winter.

Basically, we decided that this will become my plane and Natalie will have the other one. There are too many things I wanted to change that she wasn’t sure about. The plane is going on an extensive diet. I’ve already removed 25lbs from the plane and have my eye on roughly 25lbs of weight that I still want to remove. Some of easy and some of it more difficult.

mike92104
08-14-2019, 10:15 AM
Use a heat gun and a flat head screwdriver...

Thanks Josh.

rv9ralph
08-14-2019, 01:43 PM
To add to this, be careful not to overheat the spar. According to AC 43.13-1A (older version) stated that heating structural heat treated aluminum above the temperature of boiling water could affect the heat treating and structural integrity.

Just check and be careful.

Ralph

mike92104
08-14-2019, 02:38 PM
Thanks for the tip.

Delta Whisky
08-14-2019, 06:41 PM
Josh - does the epoxy appear to be Loctite 9460 that we are now using? If so, the spec sheet says the Tg is 68C so you should have room to get it off and protect the 100C limit Ralph wrote about. Good luck and let us know how it goes.

alexM
06-28-2020, 09:51 AM
If anyone is looking for an update on this project, it’s taken a back burner over the summer. Life is just too busy right now. We will dive back in the winter.

Basically, we decided that this will become my plane and Natalie will have the other one. There are too many things I wanted to change that she wasn’t sure about. The plane is going on an extensive diet. I’ve already removed 25lbs from the plane and have my eye on roughly 25lbs of weight that I still want to remove. Some of easy and some of it more difficult.

I would like to bump this thread for two reasons. First, where are you getting the 25 pounds from (and the proposed second 25 pounds)? So far this morning I've been sipping coffee and reading other people's build threads and I've learned that I should be happy I don't have the adjustable rudder pedals (gives me more room in the tunnel up front and of course saves weight, time, complexity).

Secondly I'm still mystified as to how people are deconstructing wings. The wings that came with my plane were originally built with the 3M adhesive. I'm quite familiar with what Tg is and I can get the Loctite stuff off pretty easily, but the older 3M stuff does not seem to to ever turn rubbery before the wood gets too hot. I'm sitting on new spars, extrusions, ribs and fittings so the only thing I'm going to use from my old wings is the drag/anti drag tubes and fittings. But I would still like to know how people are getting ribs off without screwing them up.