felixone

I have recently acquired a Sig Somethin' Extra, and am in the beginning stages of determining what mods I want to do. This is not my first kit, however it is has been nearly 15 years since I built one. I have previously built a PT-40, and the wings for a P51 (never finished the kit). However, as I said both of these kits where done a very long time ago, so any thoughts and suggestions would be of great help.

I have read through most of the build threads I could find for this model (as well as a few others such as RCKen's PIF thread), and compiled the following list of mods:

[ul][*] Rudder Counterbalance[*] Rudder Extension[*] Elevator Counterbalance[*] Sullivan Tailwheel[*] Pinned Nylon Hinges[*] Upgraded Pushrods (Haven't decided on type yet)[*] Sheeted Turtle Deck[*] Possible Fuel Tank Size Increase
[/ul]

In addition to these mods I have considered replacing the landing gear as well as modifying the method used to join the wings. I am not sure if I want to do some sort of bolt for the wings or some other method. I have seen some people are using a steel spring. If anyone has a source for these please let me know.

Now I have a couple questions about my choice of rudder/elevator mods. The method I am choosing to use is cutting the ends off the horizontal stab and attaching them to the elevator, and doing the same for the rudder. The rudder extension I plan to do by essentially cutting the rudder in half and inserting about 1" of balsa to extend it. What I really want to know about these mods is how much of a difference will they make. Also with the increased surface should I upgrade to a heavier duty servo? I am planning on using Hitec HS-325HB servos on all but the throttle. Would these be sufficient, or would you put a high torque servo on the rudder?

The next question I have pertains to the turtle deck. I see a lot of people using 1/16" balsa for this, however while at a craft store today I saw something that I think would work even better. They had 1/32" Aircraft Ply. This stuff bends like you wouldn't believe. Now I didn't try bending it as much as it would take to cover the turtle deck because I didn't want to break it. Has anyone used this stuff, or should I simply stick with the balsa sheeting?

Lastly I wanted to ask what size fuel tank most people use. The instructions call for an 8 oz. I had contemplated using a hatch for tank access, but I recently read in one of the threads that if you lightly glue the fuselage section of the wing tube in such a way that you can remove it if you need to the fuel tank slips in and out easily. If possible I would prefer to do this method since it requires fewer structural mods. Has anyone had any experience with doing this with a 10 oz. tank? I don't generally run into situations where I fly more than 10 minutes, but I like having the flexibility if wind conditions force a few attempts.

In addition to this list of mods, if anyone has any "must have" mods I would love to hear about them. Also if anyone who has done any of the mods listed have any suggestions on completing the mods list I would love to hear them as well.

Anyway, if anyone can help with some of these questions I would definitely appreciate it. It is probably going to be a few weeks before I can start building so I have plenty of time to hash all of this out. Although there are quite a few on here already if I don't screw up too bad I might even try running a build thread.

Thanks in advance for the assistance, I look forward all of your suggestions.

ChuckW

I definitely agree on the pushrods. The supplied nylon rods change in size quiate a bit as the temp changes throughout the day. I'd just go with 2-56 steel rods but something like CF is always an option.

The landing gear is another thing that needs replacement. it is too weak and too short. www.tntlandinggear.com has a great set for this airplane.

The other modifications are more a matter of preference. I sheeted the turtle deck on my last one, turned the engine on its side and made a balsa cowl. If you do a cowl, use a 2.5" or larger spinner. I used a 2.25" and always thought it looked goofy; it was just too small and the lines of the cowl were awkward in my opinion.

somegeek

My Feedback: (2)

Don't need to go so thin with the turtledeck sheeting(IMO)... http://www.rcuniverse.com/forum/fb.asp?m=4014606 As long as you soak the material and work it while submerged, it is very pliable.

I added an extra inch to my rudder, if I could go back I'd add 1/2 more to the rudder for more 3d authority. I didn't add any material to the elevator and wished I added an inch.

I'd disagree that the stock landing gear is weak. It's stout if you're not bouncing your plane off the ground. I used some aftermarket gear and bent it down for another 3/4" of clearance. Pondering going to a 13" prop and have the clearance if I want to.

I went with carbon fiber pushrods but used metal clevises w/ cable material for the servo side connection to minimize binding(pics in thread link above).

A tank access hatch is very nice. I didn't add one but a guy at my field has one on his SSE and it's nice to be able to open that area up to see what's going on.

Wait to install the innermost ply wing caps until you can put the wing in place with the wing tube. This way you can use toothpicks to assure the rib is flush with the fuselage and add glue drops to fill the gap in a few places to keep it flush. Comeback later with filler.

When balancing the plane, cover the wings last. I did this so I could add my lead to the left wingtip before closing up the wings.

Using triangular stock for your hinge edge makes quick work vs sanding the leading edges of your control surfaces to an edge.

When installing the antenna tube, you can create that 90 degree bend by holding the tube over an oven burner and bending and then holding til cool. Can do the same with a heat gun.

Good luck! This is a great build and awesome flier.

somegeek

yel914

Personally, I'm rethinking the removable tank hatch cover. I do think it weakens the fuse structure a bit. If you can still manage to remove the tank from the fuse without a hatch, I'd consider it. Yes, it's a PITA, but how many times do you really need to remove the tank?

buzzingb

My Feedback: (2)

I would use the fuel hatch idea as it is almost a must for this airplane. I have used the extra rudder and elevator before but it isn't necessary unless you are looking for 3d and then you need to look for another plane. I put a tower 75 on my last one and used it as intended as a fun fly and it really was fun to fly.

rcted

I built a SSE for my son a while back. I went with a Sullivan tail wheel also. Made things allot stronger in my opinion. I would suggest modifying the wing mount. I didn't initially, and went ahead with the rubber bands shown in the plans. My son took off, and the left wing and the plane parted company 6 ft off the ground. When I rebuilt it, I epoxied maple blocks inside the wing against the first rib where the hook screwed into the wing, and drilled and tapped it for a 1/4 20 nylon bolt. With a ply reinforcement inside the fuse, it results in a very solid way to mount your wings. Should have listened to that little voice that sometimes talks to me while I'm building. Hope yours flies as well as my sons.

MasterAlex

For what its worth ...

I added a sullivan tail wheel and am glad I did. I added a fuel tank hatch, and although I haven't had a need to use it, will be glad I did once I have to troubleshoot any fuel line or tank issues. I did NOT modify the wing attachment method, however, instead of rubber bands, I use a ZipTie (I think I got that tip from RCKen a while back ). I did not sheet the turtledeck and it was a pain for me to cover - I don't mind the end result, but if I had to do it over again, I'd sheet it.

As others have said, this is an awesome flying plane.

felixone

Thank you to everyone for the great suggestions.

To address some of these...

The hatch is something I have gone back and forth on quite a bit. I will probably make a decision on this once I start assembling the fuselage. Since I am contemplating putting in a 10 oz. tank the hatch might end up being more of a requirement. On this topic, I am thinking of using a Tower Hobbies .46 in my SSE. I used to completely blow dismiss them, but recently I have had a couple people I trust tell me they are pretty decent for the money.

Somegeek, I hadn't seen your build thread before but it was great. Your thread will prove to very helpful. I definitely like the idea for the triangle stock on the control surfaces. I also like the idea of attaching the wing caps after the fuselage is complete. I don't think I am going attempt making a custom cowl. That is a little more than I am willing to invest.

I am going to investigate the CF pushrods though. I have never used them, although I am expecting they will probably cost more than I am willing to spend. I currently have a Big Stik that has nylon pushrods. I bought it used so I am not sure of the brand (black outer tube, yellow inner tube). I have noticed that during the really hot part of the summer the trim changes throughout the day. The plane requires a bit of up elevator trimmed in, and during the hottest part of the day I have to add a bit more. Actually it seems like I am constantly adjusting the trim on this plane. Given this I am going to use something a little more rigid for the elevator and rudder. Most likely I will go with 2-56 rods, or maybe even 4-40. I like the ball links but haven't seen a good selection in 2-56, although I admit I have really started looking yet (just been browsing the local hobby shops).

I saw in one of the many SSE build threads that someone was recommending the Dubro tailwheel assembly over the Sullivan. Their logic was pretty good, however everyone I know uses Sullivans. I am going to have to give this some thought too.

I am still looking for any input from anyone that put counter balances on their elevator and rudder to see what kind of affect it had on performance. I might not have mentioned it in my previous post but I am mainly doing these for aesthetic reasons so what I am really after is if anyone had a negative experience. Assuming they don't make the plane harder to handle then I am definitely going ahead with these mods.

Like I said, thanks a lot for the advice so far. I would still love to hear what anyone else has to say on the matter.

Thanks

nickj

I built mine pretty much stock and it flew great--very light, plenty of vertical on a .46. I added wing bolts but they were a pain to attach--no way to get a screwdriver into the fuselage so I had to tighten them with bent piano wire. The stock landing gear was more than strong enough for such a light plane.

AZTWINS

Does anybody have a picture on how you made the fuel tank hatch?