Sukhoi_Madness

Hi all,

I’m building a Sig Mid Star and seeing as I’ve had so much enjoyment reading all your build threads I thought I’d repay the favour with one of my own.

A quick bit of background information –

I’ve not flown for 3 years, and haven’t pinned a part to a board for more than 4 years. The hiatus hasn’t been because I didn’t want to fly, but due to the fact I relocated to the UK several years ago – had to leave all my airplanes behind and life hasn’t allowed me to get back to the hobby until now.

I was an OK sports flyer before the break and am hoping I can get my wings back without needing a trainer – the Mid Star should provide a suitable platform for this and a good air frame to transition back into aerobatic low wings with.

Modifications:

I’ve considered several modifications to the original design based off of what I’ve read on RCU as follows:

- Dual aileron servos

- Tail dragger conversion

- Enlarged control surfaces

- Cowling the engine

- One wing bay clipped

- Dihedral removed

I’m going to do the dual ailerons and tail dragger conversion – I think this will make for a better airplane. The wing and control surfaces I’m otherwise going to leave stock – if I need bigger control surfaces they can always be retro fitted but to be honest I don’t think I need them for the purpose and I’d prefer to keep slow landings and stability while getting my chops back so the wing will otherwise be stock.

Cowling the engine is something I really want to do, but I’d also like to get back on the sticks ASAP so don’t want to add additional build time – undecided at this stage.

Engine

I’ve got a Super Tigre GS-45 and an OS FX 45 – both will do the job and are more than enough power obviously. Will probably use the ST and save the OS for my next model.

Glue

I’m using wood glue as opposed to CA where possible – and epoxy where required. The is my first time using wood glue, previously I used CA as my patience wouldn’t allow waiting for glue to dry – this had an impact on build quality! I will be patient this time!

I’m planning to take plenty of photos and post them as I really enjoy looking at photos of other builds as they take shape – I also promise I’ll finish the build and it won’t die!

Sukhoi_Madness

Here is a shot of my building environment.

Previously I had a full workshop with every tool under the sun – this time I’ll be working with a very basic setup and as we live in a small apartment I’m literally building in our hallway – isn’t the misses going to be pleased when she get’s home.

Aside from a drill and covering equipment this is more or less my complete workshop.

Sukhoi_Madness

First time I've pinned a part in anger for four years. I'm using Bostik wood glue - the glue joint is stronger than the wood and the drying time allows for good progress to be made while still allowing time to position parts. Can't believe I used CA before.

oldvet70

My Feedback: (10)

I once built a Mid Star on the dining room table. Had to move everything to eat.The taildragger is an option that's shown in the kit and makes the plane lighter. I never put 2 servos in the wings on one, never thought it needed 2, just more expense and weight.

The plane will fly quite slowly as designed but removing the dihedral will cause it to need more speed landing. Same with removing a wing bay. It will still land slower than many planes however.

I'd think you should have fun building and flying this plane. Best of luck.

Sukhoi_Madness

Thanks, the dual aileron servos are more for the enjoyment of doing the modification than a necessary inclusion.

I expect it’ll give a little more roll authority once I start chucking the model around a bit, but I think most Sig models are pretty decent out of the box.

The wood is all great quality as well – I’ve read a few posts on Sig struggling for Balsa, I don’t know when this kit was made but the wood in it is very nice.

Alex7403

The mid star is a very good airplane to build and to fly!
built two midstars one is still flying very well even after two nose in concrete stubborn airplane.
build it as tail dragger it balances better but the supplied tail wheel bracket is a bad idea I used the sullivan instead.
you really dont need to enlarge the control surfaces on the midstar, I rated them down so the rolls will be a bit slower.
its better to get the GP hinge slot machine other wise it can be difficult.
the supplied nylon nyrods expand with heat I used sullivan composites in the existing sleeves.
cowled engine IMO once you have a canopy on any airplane it attracts all attention first, now to fuel and deal with the engine and its cowl....
the midstar designed for flying and torture - simple rugged and very beautiful the pictures dont do it justice.

Sukhoi_Madness

Some more progress –

I’m going to use the 5th wing bay from the centre for the aileron servos. I’m going to add a doubler to the wing rib either side of the servo bay – the last airframe I built with dual aileron servos was a 4 star 60 and I can’t remember what the structure looked like, but I feel with the rear spar being balsa I could do with a little extra strength in that area. Plus it’ll get me thinking about how this airplane may be built into a twin at some point.

The doublers (pictured) have been made form one of the scrap pieces of light ply from the punch outs in the fuse sides.

I realise these where removed in the first place to lighten the airplane – but I’m sure with the size of this wing and a .45 up front a few extra ounces across the whole dual aileron modification is going to make little difference to how it flys.

I’ve also started installing the shear webs.

(NB: I’m hoping around the build steps a little to be able to continue building while I wait for parts to dry – this is a bad practice if you’re contemplating your first build)

gstockton

looking good they are a very good plane i build one a few years back loved it

gstockton

looking good they are a fine plane i build one a few years back and plan on another one someday i too now use wood glue and like it

Sukhoi_Madness

Using wood glue has worked out great so far.

I'm sure there will be a couple of areas we CA comes into play but for the bult it's wood glue.

ted1191

My Feedback: (6)

I'm all for using wood glue. These syringes are the cat's meow for applying glue, especially along the edge of ribs, etc.

Sukhoi_Madness

Some more progress –

Finished installing all of the ribs for the first wing half including a paper tube for the aileron wire.

I made a bit of a mess of the holes in the ribs for the tube – I bought a brand new 12mm drill bit to make sure it was nice and sharp and tapped the ribs together for drilling. The two W2 ribs drilled out fine with a nice neat circle but the drill bit chewed into the W1 ribs causing the holes to be less than neat. No real damage but little imperfections annoy me.

I’ve since read a post where the builder used a piece of sharpened metal pipe with a right angle bend at the top for a handle to cut out perfect circles for this purpose – I’ll remember that one!

Also, was saved by the wood glue today (I’m sure it won’t be the last time). I glued the final inboard rib in without inserting the paper tube – there would have been no way of inserting this had the final wing rib been in place. I realised my mistake and was able to remove the rib before the glue dried!

Sukhoi_Madness

Pics added.

tarvma02

My Feedback: (3)

I couldn't agree more with the Monoject syringe for applying wood glue. Cheap from any medical or dental supply company. I've been tacking my planes together with medium CA and then running a bead of wood glue along any joint. I use epoxy for the firewall, wing, gear mount, and gluing the tail on. CA is too brittle for a long term plane. CA+Wood glue makes planes that will last 10+ years!

Mike

Sukhoi_Madness

Let's hope 10 year old glue joints are something this airplane has to be concerned with one day.

Sukhoi_Madness

More progress,

Have installed the other spars and leading edge and completed the top and bottom sheeting - not sanded clearly.

This is a nice kit - if you where going for it you could probably knock out both wing halves in a day.

vmsguy

Looks good so far. I've got one of these kits waiting to build.

I use forstner (sp?) bits for drilling large holes. 1. Make sure there scrap wood behind the rib so the bit doesn't blow out the balsa. 2. Make sure the rib and the scrap are firmly clamped together.

Sukhoi_Madness

I've just checked on of those out - yes great idea. I think I also failed because I had scrap at the front, but not the back.

Sukhoi_Madness

Further progress – began sanding...

I’m not sure how this is going to work out inside the house but I do know I’m going to be in trouble when the Mrs sees the below.

Sukhoi_Madness

I got the first servo bay more or less built today.

It’s built similarly to the way you would do a 4 Star 60 wing. The cover has been fashioned from one of the pieces of light ply removed from the fuse sides.

Close to a complete wing half now – I can’t make up my mind whether or not to add the wing tip.

It’ll certainly make it more difficult to cover but will it add anything to the airplane?

bigal126

My Feedback: (18)

Your decision. Here's something I came across. BTW, the midstar is notoriously a slow roller. I have a midstar and love the plane. http://members.cox.net/moormanrc1/WingTips.htm http://members.cox.net/moormanrc1/RCUCatalog.htm

Sukhoi_Madness

Thanks, and interesting read. Seems like the best plan is to add the wing tips then remove them when I want the roll rate sped up.

Sukhoi_Madness

I’ve run into an interesting situation.

I need to order a new muffler for my Super Tigre engine and having scanned through tower hobbies I’ve seen that I can get a nice [link=http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXZ653&P=0]Macs muffler[/link] for about the same cost as the original setup.

I can’t find a technical drawing showing the distance between the muffler flange and the inside of the pipe – so I can’t be sure it’ll clear the fuse sides without major work to the fuse or another flange.

I have about 3/4 of an inch between the engine head and the outside of the fuse.

If anyone is wise to whether this muffler will work or not please let me know.

Thanks.

oldvet70

My Feedback: (10)

Best answer is to send Mac's an email; [email protected]

Sukhoi_Madness

Thanks - I couldn't find contact details on their site.