Alex7403

Hello All,

I'm building Sig mid star 40 from a kit.
i flew a trainer and a low wing. my last flight ended with a crash of a low wing 40 scratch built "hawk" , on approach for landing the plane was too slow and just fell from 30 feet, the damage was bad enough not to fix it.

it was about 6 years ago, so i decided to improve my landings with something more aerobatic then a trainer but slow and easy landing.

so im building a Sig mid star 40, im at the stage of attaching the wing to the fuselage.

the engine i purchased is: OS 46 AX, i read its not too much of an overpower for this plane?

Radio choice is tower hobbies 6XM and regular servos, have anybody had experience with this radio?

Alex

Missileman

Who said it was too much power?
I couldn't dissagree more. The left stick controls how much you use. You don't fly full open all the time.
The 46 AX is a great engine for a 40 size plane.

XTOL

The Midstar is a good choice. Its what I used for my 2nd plane and
the first plane that I really learned to FLY. And I still have it
and drag it out a couple times a year for a few flights.

Build as a tail dragger but replace the stock tail wheel wire with
a Sullivan unit. Its fine as a trike (it builds either way) but its
really excellent as a tail dragger.

The 46AX will be great on it. I powered mine with a Thunder Tiger
TT46 Pro.

pt40crasher

Looks good! Lets see more pictures when you get done.

RCKen

My Feedback: (9)

That's a great engine for that plane. You'll do fine with it.

Ken

Alex7403

moved it else where

Alex7403

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jetmech05

I fly the 46 ax on my mid star love it

Thumprding

Actually I would be looking for the strongest 40 to 50 sized two cycle I could find. Always nice to have that extra kick when going vertical. Plus like some one else said the left stick controls the power. I have a Easy Sport 40 with a 61 stuffed in it and it flies just fine.

rlipsett

Lack of power is more dangerous to a plane then being overpowered unless in the course of overpowering a plane you add too much weight to the plane and it becomes unstable or you have to fly like a banshee to generate enough lift to fly

sporty982000

I am building the sig mid star 40.

I was wondering for those who built it, if they added extra sheeting on the wing at all ?

I was debating to add a strip along the leading edge on top and bottom.

Also, the wing tips. this looks fairly hard to cover and to cover it well.

Did anyone add any extra balsa there to help with a more uniform covering in the wing tips ?

Sporty

Alex7403

i didnt add any sheeting on the wing, i added some fiberglass and glue inside the covered part of the wing, and a wider fiberglass on the joint of the wing. im not sure its necessary.

yes im looking at the wing tips and wonder how am i gonna cover it.

Alex

sporty982000

I got a o.s. max 40 for mine. Its used but in good shape.

I ordered some extra 1/16 x3 x 30 for adding a little more to ther leading edge of the wing tips.

I have still been rolling around the idea, off adding or doing something with the wing tips.

Maybe not covering them, but making some more braces, like the ones supplied in the kit. I would just like some more contact, sealing.

As I wonder if the limited places to seal / heat to contact on the edge, if it will hold well out of all that open area.

Sporty

MasterAlex

I've seen people simply omit the wing tips - seems to fly just fine. At least from a spectator's perspective.

sporty982000

Well I ran out of Ca and 5 min epoxy, but I am still pretty close to being done.

I need to install the rudder, tail, alerons and get the hinges on. But Thats all that is left to do, before I start covering.

Hopefully two more weeks I will be done.

I did get extra sheeting, but have not put it on, I may not after all. as It looks like I will either have to sheet between the rips, as if I go ontop, I will have to cut down for a proper fit into them.

Sporty

Sporty

Alex7403

Hello Sporty

Im before sanding the Mid star for covering, as a matter of fact I like covering now!

Covering is fun, did the control surfaces, with Help from Minnflyer videos they are great, Taught me self to enjoy every moment of ironing monokote… so far so good

I think there might be an issue behind the canopy, there is a big gap to cover with no wood to back it up, so I added so balsa pieces between the fuselage and the balsa beam.

The thing that is coming up from the fin i intend to be an antenna tube.

Alex

elenasgrumpy

My Feedback: (4)

No problem at as far as over-powering it. I run it in a WM Ultimate 40. It's a hot little item & the OS .46 AX is a great high quality engine IMO, but it aint no super power house. My Tower .46 Pro will run circles around it when it comes to pure raw horsepower. I can prop them the same, on the exact same airframe, (as in same weight too) & I guarantee ya my Tower .46 will lap my OS .46. How many years it will continue to do so is another question. Meanwhile I have an OS .10 that was my Dad's from 1964 that still runs like a Swiss watch!! So I believe the OS out qualities the Tower, but the Tower out powers it hands down.

Dawning flame retardent suit so go ahead, have it.[sm=pirate.gif]

JollyPopper

My Feedback: (6)

I agree that the Tower .46 is a real powerhouse. I have one and it is a hoss. But isn't it physically bigger and some heavier than The OS AX .46? I don't have one of those but intend to get one to nail to the nose of my as yet unbuilt Great Planes RV-4.

elenasgrumpy

My Feedback: (4)

Jolly, I just checked Tower & the weights are all pretty close. OS .46AX W/Muffler = 17.2oz, Tower .46Pro W/Muffler = 16.9oz, & the TT Pro .46 W/Muffler = 17.01oz W/Muffler so they are all 3 right there in that 17 oz range with a .3 oz difference between the heaviest & the lightest. Personally I wonder if the TT isn't the best bang for your buck among the three. I don't own one but have many friends that do & have been nothing but impressed with the smoothness of the way they idle & run as well as having good power too! They seem to hold an idle longer than my OS's without loading up too. All around a good high quality strong running engine from what I've observed. Just my personal opinion though.

Just food for thought a friend bought the new OS .55 & hung it on the front of his WM Dego Red & it's really scoots along well. Seems like a really nice engine!!


http://www2.towerhobbies.com/cgi-bin...?&I=LXNMD1&P=0

If the extra $40 doesn't bother you, it might be worth looking into.

JollyPopper

My Feedback: (6)

Those weights are surprising. I would have thought the Tower engine was heavier, but guess not. As far as the .55 is concerned, I have read a couple other posts that suggest the same thing. Also, the .55 would give more flexibility in the future if the RV-4 meets its demise. I'm like a lot of other folks here--the $40.00 difference is a consideration, but since the RV-4 is not started yet, I have time to gather the money for the larger engine. I also need to buy a .91 four stroke for a Super Skybolt and when you're talking $395.00 as opposed to $345.00, it doesn't sound as bad. I believe that's called rationalization. Might limit my beer budget for a couple months tho.

donkey doctor

Hello; On the second Mid-star I built, I put cap strips on all the ribs from the leading edge to the spar, top and bottom. Iused the lightest 2/16 x 1/8, I put them on to make the covering look more streamlined, and less pointy. I didn't think how it would change the wings shape, but the planes performance didn't suffer. The second one flew as well as the first (and the third). I was using transparent covering on the wing, and I thought the transparent covering was more likely to puncture on those sharp rib edges.

elenasgrumpy

My Feedback: (4)

JollyPopper, I'll see if it will let me upload the engine pics here, wich me luck![sm=71_71.gif]

Sorry, Didn't intend to high-jack the thread but the site wouldn't let me send these to JollyPopper in pm, again my apologies.[sm=red_smile.gif]