After 57 years of living I can attest to the fact that I am stuck on stupid - and I now have two questions.

I am - or was - nearing completion of a Sig 4 Star 40 which my wife gave me for Christmas. I decided I wanted to light off the new SuperTigre .40. It started like a champ but would only run on 1/4 throttle. If you gave it any more throttle than that it would simply cut off. Then you would need to reprime the engine and restart. It acted like it was getting no fuel.[:-] Since it was freezing cold out I decided to wait until a balmier day to work on the engine.

I took the plane over to my trainer's house so we could check the servo setup. He immediately noticed that the fuel tank was leaking.[&o] Well, I had to remove the fuel tank. First step - remove the retaining spar from behind the fuel tank. Only, Sig instructs you to epoxy the spar in place - and I did. (I told you I was stuck on stupid. I should have used some wood screws.)

Well I finally managed to get the spar removed (thanks to my wife who got me a Dremel tool for Christmas). I then discovered that when I had installed the fuel tank I used too much silicone. Instead of silicone around the neck of the fuel tank where it could easily be cut out, I also got silicone between the front of the fuel tank and the back of the firewall where it could not easily be cut out. (I told you I was stuck on stupid.) Well, I worked with an Exacto knife and a small screwdriver and I got almost all of the silicone out. I decided that I could use a larger flat-bladed screwdriver to push out the fuel tank. I carefully placed my left hand on top of the fuselage slightly behind the firewall and I carefully placed my right hand on the screwdriver. I then pushed - it gave slightly. I then pushed harder - it gave a bit more. I then pushed with all my might and the tank broke free![sm=greedy.gif] Oh yes, the screwdriver was also free to travel in a backward and slightly elevated direction. It went through the top of the fuselage behind the firewall where it came to rest ---- 3/8" deep into my left hand![sm=lol.gif]

My wife assures me she can repair the puncture wound in my left palm. She has no idea how to repair the puncture wound to the top of the fuselage slightly behind the firewall! That is my first question - can you give my any advice? (When responding, please remember that I am stuck on stupid.)

Second quesiton: I quickly discovered why the fuel tank was leaking (and I probably also discovered the source of my engine problems). When I installed the motor mounts I used 4X40 bolts which were about 3/16" too long and one of the bolts entered into - the front of the fuel tank. (I am fairly certain that was the source of the engine problem - I was unable to keep the tank pressurized and, when called upon, the engine simply did not get enough fuel to run at full throttle.) I then set about replacing the bolts with shorter bolts. Second problem - one of the back nuts is stripped. There is no way to get a new back nut in because you can't get to fuel compartment on the Sig 4 Star 40 ARF. I could go out and pay $120.00 and buy a new fuselage, but there has to be a better way. Any ideas?

When responding please remember that the author is stuck on stupid.

Mike,
Don't be too hard on yourself, Anyone that hasn't injured themselves or a peice of equipment with a screwdriver just hasn't used one enough times. I believe the key problem is the stripped blind nut? If so, you may want to cut a small access hatch (maybe where the hole is?) Then you can glue some doublers in and secure a cover to your hatch after you repair the nut and install the fuel tank.
John

This is stupid: trying to fix a wing into the spa with CA! Don't ask what happened!!!

Sounds like you need a sharp knife or dremel (careful!), some glue (do not glue yourself to anything you want to fly), some small pieces of wood maybe, and a new nut.

Oh yes, and the courage to use the above Just plan ahead, taking into account everything that you have learned so far.

How are you planning to put a tank in place now?

i've done the exact same thing, i think we all have at one time or another. like perttime said learn by your mistakes, plan ahead and continue the hobby. it gets better i promise.

If you have any 1/8 balsa sheet, just cut out a piece the size of the top deck between the front of the cockpit and the firewall. Make sure the grain runs front to back, and just glue it on top of the current damaged piece, then sand the edges to blend it into the sides. The 1/8 extra thickness should not matter. You could also cut out the entire piece that is broken (Stabbed ) and make a removable panel to make tank insertion / removal easier. You are building the plane, so I am assumiong you have the skills to do the mods.

Don't beat yourself up on this, we've all had episodes where our gray matter has temporarily vacated the premises. Just to be safe, use a dull screwdriver next time

After re-reading your post, sounds like the access panel is the way to go, this will give you access to the blind nut. Just measure the length of the tank, as make the panel about an inch longer. Just don't go past the fuse former. Add some hardwood strips to the sides of the fuse(inside) to screw the panel on, and use servo screws, or something similar with a small washer. When you re-mount the engine mount, take your dremel tool with a cut-off wheel and trim the ends of the screws that exit through the blind nuts so they are flush.

The 4-Star is a great plane to modify and kit-bash, it lends itself well to repairs, too.

An access hatch would be the best bet, but if that intimidates you, then you could try this: Get the stripped blind nut out. If it's epoxied in, then hold a soldering iron on it for a few minutes, and it will fall out! careful, though, because if it falls out onto some covering inside of the fuel compartment, then it will burn a hole through it at this point. If it falls out onto wood, then you will be fine. Once it falls out, get it out with some needle nose plyers. Now, to re-install a new one up in a hard to reach place, go to the hardware store and get yourself one of those telescoping magnets used to pick up tools and bolts and such dropped into small places. One can be had for about a buck or two. They look like an antenna on a transmitter, but they have a magnet in one end. Put the new blind nut on the magnet, and carefully place it up into the firewall from behind. I've done this numerous times.
Now, for the hole. You could go through the trouble of redoing the wood, or you could just get some covering of the same color and iron over it. You'll have to look very hard to see it, and once in the air it will be invisible!

Dear SOS ,

First, don't feel bad, we all have our moments. One time I noticed fuel dripping out of my plane the first time I filled the tank. To make a long story short, when I was drilling the holes for the cowl, the bit went straight through the top of the tank. [X(]

Others have given you some ideas on repairing the broken sheeting. I'll give you some ideas on the engine mount nut. I assume when you say "back nut" you mean a blind nut. The first issue will be removing it. Most likely when the ARF was assembled they used a little glue to secure these. To remove it, try screwing in the bolt in as far as possible and then tap it some with a hammer (but don't get carried away and end up with another screwdriver-like moment). If it doesn't come out this way, try a bit of heat. Take a soldering iron or gun and heat up the bolt. This will transfer some heat to the blind nut, which should soften the glue. Once the glue is softened, try hitting it again to drive it out.

Once the blind nut is out, it's time to install a new one. If the nut is metric and you can't find a replacement, don't sweat, just get a similar sized one and use a new bolt. Once you have the new blind nut, the challenge will be installing it. First you need to get it in the hole. A method that's worked for me is to use something long and thin, such as some music wire. Push it through the hole from the front until it comes out in the radio compartment. Slip the blind nut on it and let it slide down until it gets to the firewall. Then use a screwdriver, needle nose pliers, or whatever works, to press it into the hole. A little mirror (borrow a compact from your wife, or get something like a dental mirror) works great to let you see what you're doing in there.

Once you've got it pressed in it's time to carefully thread the new bolt in. I say carefully because you don't want to push too hard and have the blind nut pop out. When you've got the bolt threaded in, tighten it down to firmly seat the prongs on the blind nut. When this is done it's time to apply some glue to the blind nut. There are a couple choices here. I've had good luck applying thin CA through the hole in the firewall. A small amount will run down the hole and then wick into the wood. Note, remove the bolt before applying glue. Also, be sparing with the glue. You don't want to apply so much that it starts filling the threads. Another choice would be to apply a bit of CA on the end of something long and sharp and try to get it on the prongs of the blind nut. Depending on how you are at working in tight places, this might work.

I've used these tactics to install an entirely new set of blind nuts in a .25 size ARF, so I know it can be done for just one. Hope this helps.

to replace the blind nut, go to home depot (or equivilant) and if you have 6-32 blind nuts (or what ever size needed) and get a long piece of allthread rod, i screw it into the old blind nut and just wiggle it out and straight through to the access hatch.

now, to put the new blind nut in just reverse the process but first put a regular nut and semi large washer on the other end of the allthread so it will be on the outside of the fuse, now put the blindnut on the end that is sticking out the access hatch and pull it into position where you want it and then just tighten the nut down that you put on the outside and it will pull it in tight!

and also the access hole im talking about is not one you cut in it, its the one already there where the servos are

good luck!!!

ps your not the only one who chops himself up in this hobby

Sounds like you have a very devoted wife. I'm sure she will be there for your when you come home with your knuckles all bloody. Your trainer will explain that. Just be careful . You will develope a safe routine as you get going.

You know how a dog will "perk up" when he hears a stranged noise? Well there is a very distinct sound when ones knuckles get zapped. Then everybody "perks up" and looks around to see who it was

Good Day Sir..

Rest assured we all take our turn at being a Dumb*****.. I have even been known to but in line.. but your troubles are easy to repair..the posted methods for removing the stripped blind nut will all work.. I usually just put in a screw from the front end and give it a solid hit with a ball peen hammer and that seems to work as well.. I hope you didn't seriously hurt your hand..

PS: I work with aircraft and I have done everyting from drill through my finger (yeah ouch) to grind off 98% of my finger nail..with an air powered dremel. (Thank goodness it grew back) I must have been butting in line that day..

Enjoy your 4 Star..

Riverdancer

Thanks for all the help. I have received a lot of laughs reading your replies. I still feel stupid, but I don't feel alone. I'll let you know how the repairs progress.

Mr. Meyer-- Nothin' personal, but you GOTTA get yourself another avatar photo, something like Cyclic's or Riverdancer's, or heaven forbid, a guy in a skirt like Piper Chuck's
Your picture looks like it came out of the First National Bank boardroom, or the CIA front office.

Hey , heres another "classic." You know the strap that goes around your neck to hold your transmitter. While your leaning over the engine, well you can guess the rest[X(]

You know that was the first thing I noticed but didn't say anything. Actually you should leave it because there is no other one like it


With a mugshot like that, you should become a Moderator here. We need discipline!

The things you went through is just part of the learning curve that we all go through. The advantage these days is having such a great place like RCU to get advice when you get stuck.

A photo of you holding that new plane at the flying field would be nice too!!!! Capt,n

The honesty of your real picture and name and location is refeshing to me. Leave it alone. I don't care for all the non-revealing screen names and folks not wanting to list thier locations. . My 2 cents about that. Brian Smith Tullahoma Tn.

Kilt laddie, it's a kilt! And in case you're wondering, that's actually me in the pic. It's from when I was playing with NCSU pipes and drums.

What can I say? I am a lawyer. (Would you all have helped me if you had known that? )

They'd probably still have helped, but some might consider editing their posts to add disclaimers...

never know when we might need a lawer Michael so you just keep on asking Q's and well keep on answering

You know Mac Ed Swindle ?

Please do not feel bad about your mishaps. I even put my hand through the prop 20 years ago reaching for the glow driver ! Just don't do that and you will be ok lol. I still do not have feeling in my fingers and palm !

CJ

If your blind nut is stripped completely and it's a 6-32 just go to the local hardware store and pick up a 8-32 tap and re-tap the nut to the next larger size. It works great! Odds are it's already a 8-32 so you'd want a 10-32. Just take one of the mount screws with you and tell the guy you want the next size up. Good luck and don't feel embarrassed. I work with professional toolmakers and they do a lot worse at times. BTY is the "He Needed Killing" defense still good in Texas??? LOL

Now that’s funny.

Bill