first kit Sig Mid Star 40- Build Thread
 

After 2 years in the hobby, I've came to the conclusion that in order for me to fully enjoy this hobby... I have to start building...

My choice for the first kit...Sig Mid Star 40. Typical "rc airplane" looking model.

Mostly it will be built by the plans, the only "personal" touch will be two servos and 2 inch ailerons...

So far I've assembled the right winig (without any glue) just to make sure that I understand the instructions...

I can admit that the box full of sticks looked scary at the beginning but now...I'm hoping for the long winter.....

pictures will follow shortly...

Any advices, tips, hints etc...will be greatly appreciated!!!!

RE: first kit Sig Mid Star 40- Build Thread
 

Just read ahead in the instructions,prior to glueing
any parts together. Take your time and enjoy.
Post pics when you can,

Bob

RE: first kit Sig Mid Star 40- Build Thread
 

Looking forward to it!

RE: first kit Sig Mid Star 40- Build Thread
 

Great choice. One thing I really like about the Mid-Star is that it only comes in a kit. As a result, I see very few at my field, but they are all great flying planes.

Good luck.

RE: first kit Sig Mid Star 40- Build Thread
 

Yes I agree with all that is written above, read the instructions before building and its a great airplane.
Built two mid stars, the last one is still flying very well stubborn airplane.

RE: first kit Sig Mid Star 40- Build Thread
 

I,m looking forward to it also and you picked a great kit , for your first one. I just finished my 3rd 4 Star , so I,m going to post a few pic,s to give you some insperation . lol
After flying the 4* with one bay clipped out of the wing , I highly recommend this. Mod. Lands much better and the roll rate and handling improved notciably.. Also added and inch to the rudder and 3/8 to the elevator . Knife edge improved , but still wants to tuck to the belly ,like every other 4 * I,ve flown. Reinforced the wingfuse behind the wing saddle and tried to build it as lite as I could.
Remember , pic,s are cool ?http://www.rcuniverse.com/forum/js/f...ades_smile.gif

RE: first kit Sig Mid Star 40- Build Thread
 

OOOPs , my bad , I need to make sure I have had my coffee before I post in the forums , lol Sorry about that.
Yes, a Mid Star build well be cool as I,ve never the chance to be around one, nice to have something different for a change.

RE: first kit Sig Mid Star 40- Build Thread
 

Think about tapering the ailerons. Mine were 2" at the fuselage and 1 1/8 at the wing tip. I did this to keep the twisting of the wing tips to a minimum and most of the stress to the center of the wing as the front of the wing is not boxed in. Keep the rates low for a while.

Have you though about a motor? My midstar was flown with a 46ax, ST G60, Saito fa56 and a Saito 91. The plane flew best for a novice flier with a small 4 cycle. A larger 2 cycle made a MUCH more aggressive plane. The g60 on 15% was very nice power and gave it good vertical but added a lot of weight. Definitely go with a 4 cycle if u are using a small motor.

I hated the 46ax in it. Don’t get me wrong the 46ax will pull the plane but it was hard to maintain energy with it with more aggressive flying unless the throttle was left wide open and even then I could loose energy fast. Rolling with the larger ailerons creates far more drag. In my opinion a 46ax would be good in planes under 5lbs but the midstar builds to about 6lbs. It is designed to be rugged for beginners. There are ways to reduce weight but as your first kit I suggest that you don’t.

Keep in mind I am talking here in terms of a non-novice flier. A novice flier would find a 46ax a lot to handle. If I was to get another I would power it with a 75ax. No pump. A 55ax would be nice but not much over a 46ax. I know people here will say "What a 75ax!!" [X(][X(] But I like power and I use heavy throttle management. I'm not saying this is for you. But a 75ax can be run on 5% or 10% nitro for lesser power (you could even prop the engine up a bit to reduce rpm) and then you have an engine for the next kit like an ultra sport 60... The very same servos used in the midstar can also go into the ultra sport. If you go with a larger motor you will need more prop clearance. The Dubro glass filled gear work great or a set of aluminum gear from an ultrastick 60. Most hobby shops stock these gear.

If you go with a larger motor stay away from the super tigres as they are heavy:

Super Tigre G60 with muffler 28.8oz
OS 75ax with muffler 19.4 oz

9.4 oz, that is a drastic weight difference, almost ¾ of a pound!!...

Also don’t fall into that fear place where you think a 75 is going to be crazy compared to a 60. It is not. (For a novice flier it would, but again that is what that left thumb stick is for…)

With the G60 on 15% with a MA 12-5 at full throttle I could maintain about 1.5 rolls per second in a vertical upline one after the other without loosing power. Keep in mind the engine was pumped (because the front bearing was leaking air and I needed the pump to keep the fuel at the carb) The pump was definately adding power.

If you ever fly an extra you will find the midstar to feel like an extra 260. Floats like it. It is an AWSOME pre-plane if you are going into extras or yaks

RE: first kit Sig Mid Star 40- Build Thread
 

Good recomendations. I would consider removing the rounded wing tips but not the first bay at first. Fly it for a while then consider it. Removing the bay even after flying for a while is an easy after mod. The rounded wing tips provide a more stable flight for beginers. As an eperienced flier, you will find them anoying.

Definately add to the rudder. The elevator can use the extra too. The book suggests to put rounded supports on the base of the rudder to the stab. You DEFINATLEY want to do it.

RE: first kit Sig Mid Star 40- Build Thread
 

Hello all,

So it starts...

I just glued the first two ribs (W2), so far so good...
I'm using primarly Titebond II as my glue.

Take a look...more pictures coming soon.

RE: first kit Sig Mid Star 40- Build Thread
 

Go with Tom's set-up. It was me who put that one in the trash bin! RFI victim, went 2.4 afterward! That was the second plane I flew and absolutely loved it with the Saito .91! Vertical till outta sight! First plane I hovered. Had it set up with flaperons and mixes, too. If you want to quickly progress your skill set and have a ton of fun, this is the one to do it. I still wish I had "ours", Tom. It was fun.

RE: first kit Sig Mid Star 40- Build Thread
 

I'm not sure about the round wingtips...most likely I will skip them.

I'm also thinking of bigger ailerons (2") and two separate servos.

as far as engine goes....either OS 46FX, Magnum 46 or...maybe it's time to get my first 4 stroke...we will see...

How long a servo extantions should be if I will decide to install two separate servos for the ailerons?

RE: first kit Sig Mid Star 40- Build Thread
 

The airplane builds fastest the way its written in the manual.

If its your first kit go with what the instructions say, or you can prepare for those changes building them in.

you can make the wing shorter by cutting one rib bay at any time but not the other way around.

The mid star is a great airplane as is, it likes to be a tail dragger with sullivan tail wheel assembly.

I still fly my mid star with 46 ax and love every second of it, this airplane flies on its wing not on its motor and the 46 ax is enough, to put a bigger engine you will need an adjustable engine mount.


*** mxaexm, in post #10 picture #1, the TE spur looks like it attached to the TE sheeting, shouldnt it be covered by the TE sheeting, or its the pin confuses me..

RE: first kit Sig Mid Star 40- Build Thread
 

IMO,

Build it per the Manual, you will be happy with it.


Bov

RE: first kit Sig Mid Star 40- Build Thread
 

Here is a little tip, all those oval shaped parts that are cut out of the fuse pieces make EXCELLENT sanding boards. I spray them and some sandpaper(on the back) :D with a permanent glue then wait a few minutes then slap the sheets on and trim the edges. Even some of the weird shape pieces make killer tools.

RE: first kit Sig Mid Star 40- Build Thread
 

The last time I flew my midstar (summer 2007) I flew it on the wing, the prop, the rudder... Just because it has a wing doesn't mean to limit the flying to just that... Goes to show what this simple mid-wing trainer is capable of!

All of the mods so far can be done even after the initial build. Changing ailerons can be done later. Sure try the stock ones. I did. Easy afternoon mod. In fact building the plane as per the instruction is good experience, probably better than immediate mods. Try it with the wing caps on, remove them later if you like. Even the rudder and elevator can be moded bigger later! Have fun building this plane. Don't try to build fast. Often I will sit in my workshop just staring at the plane or plans or manual just because I'll be "in-the-moment" Thinking out the best way to do something.

One thing though. If you are going to go with 2 aileron servos. Do that now. rather than having to remove all of the covering later to do it. You will need control surface horns, 256 rod and quick links. There will probably be enough 1/8 ply left in the kit to make the servo mounts. If not it is cheap from your hobby guy. You will have to cut holes in the ribs to allow the servo wire through. Don't worry you won't weaken the ribs. Wiring really depends on your radio system. If you are only using a 4 channel then you have to go with a y harness and use only one channel. I my self always split the ailerons to 2 channels (ch1 and ch6) then you can play with flaperons, spoilerons etc... With bigger planes all control surfaces always use separate channels IE: split elevator, one servo per side on 2 channels...

When building measure 3 times, cut once. Make all of your fits tight, including the sheeting. the best glue joint is a snug fit, no play. Don't use glue and epoxy to fill gaps in joints. Make them tight before being glued. I use thin ca for almost everything. I also use aliphatic resin (yellow carpenters glue) and gorilla glue. Hardwood requires glue like epoxy. On the firewall/gear mounts/wing bolt blocks I always use 30 minute epoxy. Use epoxy sparingly as it is heavy. You will be surprised to see how little is really needed.

I'm sure 2 12" extensions will reach but put a servo over the plans where you intend to put it and measure and make sure you have an additional 4"

RE: first kit Sig Mid Star 40- Build Thread
 

Alex,

in picture #1, all you see is a temporary setup (without any glue)....last night I started from scratch and glued the first two ribs...

RE: first kit Sig Mid Star 40- Build Thread
 

all right better false alarm than hobby knife to take it apart.

RE: first kit Sig Mid Star 40- Build Thread
 

Day 2

I just glued two more ribs...if I won't pick up some speed it will take me a few years to build this kit ;)

I'm trying my best to build it as straight as possible and that takes time. Using titebond II also doesn't help in speeding up the whole process..however I'm enjoying the journey and if it will take me a few months to build it, I will be happy with it.

On some of my pictures it might look like I'm using too much glue...that's only a false illusion on the pictures. I bought 30 brushes at walmart for $2, those inexpensive brushes are great to spread the glue with....

RE: first kit Sig Mid Star 40- Build Thread
 

Q-tips work great for aliphatic glue, you will need some small plastic clamps.

RE: first kit Sig Mid Star 40- Build Thread
 

you can glue all your ribs down on the bottom, then lay the top spar in ungled ...use it to position the ribs square to the building surface. Using slow glue allows you to get them all wet and have time to position it all and walk away..or go to bed. If you have a couple tables, and think it out..You can get a lot done with white glue.

RE: first kit Sig Mid Star 40- Build Thread
 

I'm living a really busy life (a lot of hobbies, work, girlfriend) I'm ok if this kit will take me a really long time and there is really no rush to complete this kit. I have the whole winter to build it and "fortunately" the winters are long in the midwest...

So far I've been enjoying the building process...and would highly recommend building a kit for everyone.

RE: first kit Sig Mid Star 40- Build Thread
 

Harbor Freight has a bunch of clamps - various sizes - pretty darn inexpensive. You have 5 of 'em in the Chicago area. Clamps are a good thing to have. Some say you can't have enough clamps. As you are gluing with Titebond clamps will result in a tighter and straighter seam. Alephatic resins (AR - like Titebond) have a long setup to give you plenty of time but they can move around if not secured. Also, the water content of the AR may result in warping if the wood is not secured while curring. Just ask me about the warped balsa sheet fuse sides & doublers on my current Bridi Killer Chaos.

On Titebond II, of the 3 primary types of Titebond (original, II and III) you have picked the one that is most difficult to sand. It may very well roll up or bead up on your paper rather than sanding cleanly. This is especially true where the seam is exposed to areas that need to be covered. The original is the best of the 3 for sanding. Don't worry about the added strength of II over the original as these products are intended for use by the woodworking industry. In our application the balsa wood will break before the glue gives.

Sounds like you have plenty of time to take it one step at a time. Have fun and you'll have a one-of-a-kind plane that you will be proud to fly!

RE: first kit Sig Mid Star 40- Build Thread
 

I have some clamps at home and I might get some more in the near future. I've read tens of build threads and most of them were using Titebond II....I will be also using epoxy and CA..so hopefully the sanding process won't be too bad. I'm really careful with not using too much glue...this is my first kit and surely a huge learning experience..

RE: first kit Sig Mid Star 40- Build Thread
 

I'm building a SIG 4 * 40 kit and the wing plans in this thread look amazingly similar....I suppose it makes sense that SIG uses the same wing plans for the low wing and mid wing .40 kits.
Like mxaexm, I'm in the Chicago area and have plenty of time this winter. I have a high wing training that I'll take out if/when we get any decent days over the winter, but mostly I'm focused on building.
I've built some kits before and I'm using medium CA for most of the joints and 30 min epoxy for joints requiring more strength.
mxaexm, where do you fly?
-Mike