Hobbico Twinstar minibuildlog (Former: The urge for a twin.)
 

Hi fellow pilots!

I'm currently thiniking of buying a twin, either kit or ARF.
I have been flying trainers for some years now, so I need a plane that is not so hard do handle. Also, it should be easy to handle outs on one of the engines.

The Hobbico Twinstar seems about right for me, at a fair price.

Do you agree with that choice, or do you have other recommendations at similar price?

--
gisi

RE: The urge for a twin.
 

gisi,
Here is a build I did on the Hobbico Twinstar...

http://www.rcuniverse.com/forum/m_26...tm.htm#2688899

If you read the whole thread you will see it is an easy ARF
to do and more than one was used in thread to compare different
engines in this plane..
To answer your question, you can not go wrong on getting this plane.. :D

Easy, fun, and is quite capable of doing more than a trainer..[8D]

RE: The urge for a twin.
 

Ok, that post convinced me. :)

Hobbico Twinstar it is!

RE: The urge for a twin.
 

By the way, would you go for two OS 25FX or two OS 32SX?

RE: The urge for a twin.
 

The Twin Star is a good choice for a first multi and as Robbie indicated it is a very succesful multi trainer. For that airplane the .25FX would be my first choice. If not for any other reason than the .25FX is just about the most user friendly in a multi installation avaliable and a superb engine. I like them so much that last year alone I purchased 12 of them for a six engine airplane and replaceing four strokes on a twin as well as a four engine airplane. There will be more this year.

I think going to larger engines on the Twin Star is counter productive in many cases due to either/or increased wing loading and possibly higher fuel consumption. The Twin Star fuel capacity is somewhat limited.

If you want blinding pereformance instead purchase Ultra Thrust pipes for the .25's from Performance Specialties (not cheap 65 bucks) and prop with APC 9x4's and its my opinion that you even realize improved throttling a big plus with any multi.

John

RE: The urge for a twin.
 

Of your two choices I would do the 25's..
As John says, more motor more weight..
With the smaller LA engines the plane flew
real good and was not that much slower but
did have longer flying time..

RE: The urge for a twin.
 

The plane is on its way now :)

Robby, would you recommend changing the included hinges to something else?

RE: The urge for a twin.
 

gisi,
Not really..
Altho it doesn't really hurt to add additional..
If you use pin hinges might last longer but at what weight cost..
Anything you add will add weight and that is something this plane
does not want to have,, more weight.. ;)

RE: The urge for a twin.
 

This is really a fast build! Can't wait to see it fly! :)

Robbie, I saw in your buildinglog that you were able to tighten the screws in the firewalls so they right about flushed with the wall. I'm about 3mm away from flushing. Will go shopping for 4-40x7/8" screws tomorrow I think..

RE: The urge for a twin.
 

Gisi,
So how about some pics and tell us what you decided to
go with for engines and what servos you are using..

Did I mention pics... :D Lots and lots of pics... :D

RE: The urge for a twin.
 

I'll post some pics late today. :)

I chose OS. 25FX's. It seems that they will provide sufficient power, and not drink all the fuel at once. Should get about 7-10 minutes of flight time I think.

As for radio equipment, I bought Futaba 7C 2.4Ghz. Tired of the old 35Mhz systems we used here in Norway:) Servos are Futaba 3004BB.

RE: The urge for a twin.
 

Ok, I'll post some pics here now. :)

The first two pics shows the wing finally joined together. Then the screws that don't flush with the firewall at all, as I wrote earlier. Need longer ones!:)

The fourth picture shows some very accurate postitioning. :)

RE: The urge for a twin.
 

Some pics showing the assembly of the fin..

RE: Hobbico Twinstar minibuildlog (Former: The urge for a twin.)
 

HI, I have flown the TwinStar for three seasons. No Problems with the OS .25 FX. I did modify the nacells to put 6 oz tanks in. The covering has not held up, stick on vinal. I am in process of removing the covering and cleaning up the fuel soaked areas. Vinal conceals a lot of sloppy construction, fixing that and sanding. The wood used in construction is very good. The ailerons have three hinges each , I will be adding a couple more each aileron. The rudder lower hinge is loose and needs to be replaced. I will not be reusing the plastic wing, stab, and rudder tips.
Will make balsa tips. Will recover using monokote. This is a fine flying airplane, lots of fun. Never had an engine out situation. The OS .25FX are now in a GreatPlanes Supersportster .40 modified as a twin. Everything set zero-zero.
Have fun, Joe

RE: Hobbico Twinstar minibuildlog (Former: The urge for a twin.)
 

I just finished mine. I had a lot of trouble with the throttle servos fitting in the nacels and operating smoothly without hitting the nacel cover. So I installed some smaller servos (JR 911) and made my own mounts for them. I put 2 .40 LAs in it so I will have to watch the time as I have the standard tanks. I also added a steering servo, simply because I HATE fussing around with a plane that doesn''t track right - taking off the cover, monkeying around with set screws, still doesn''t track, repeat process, etc. This way, I have it slaved to the rudder on a different channel so I can change the trim to get it to track straight yet it moves with the rudder. I also put the throttle servos on different channels for individual end point set up. Its just more convenient. I love computer radios.....

Hopefully I''ll get to maiden mine this weekend, if the weather cooperates. Keep us updated Gisi!

Tim

RE: Hobbico Twinstar minibuildlog (Former: The urge for a twin.)
 

Just finished gluing the nacelles to the wing as you can see on the pics below.

flyalot: It seems that you have an older version than mine. Mine looks very good, the covering job is not too bad, but have to fix some bubbles and reatach some places. Also, there are no plastic tips for my version, so no need for me to change them. :)

Only problems so far are too short screws to attach the engine mounts to the firewalls (replaced screws with 4-40x7/8"), and the left nacelle was a little bit off. Oh, and there were only 8 CA-hinges included in the box, so I used pin hinges on rudder and elevator.

As soon as the glue for the nacelles has cured I''ll be starting radio installation! :)

RE: Hobbico Twinstar minibuildlog (Former: The urge for a twin.)
 

Aiaiaiai, problems!

First the manual states that I should turn onenylon clevis into each of the four 12" pushrods. First, there are no 12" pushrods. There are however 4 10" pushrods. Put on the 10" pushrods, the clevises will slide right over where they are supposed to be turned. Did anyone of you guys have similar problems?

Also, how were you able to fasten the engine? There is no way I can fit a wrench between the engine and the nacelle... Suggestions? Other methods of holding nuts in place, without using a small wrench?

RE: Hobbico Twinstar minibuildlog (Former: The urge for a twin.)
 

gisi,
For getting to small nuts in restricted areas use NUTDRIVER as this:

http://tmt.stores.yahoo.net/cr7nuse.html

Which pushrods are you trying to do..?

RE: Hobbico Twinstar minibuildlog (Former: The urge for a twin.)
 

I''m trying to do throttle and ailerons...

RE: Hobbico Twinstar minibuildlog (Former: The urge for a twin.)
 

Gisi,

I''ll have to check but I think I just held the nuts with a needle-nosed pliers and turned the heads to tighten them (again, I''m not at home so I''ll have to check for sure). I didn''t have any problems with the rods or clevises. Sorry, that''s not much help, is it?

RE: Hobbico Twinstar minibuildlog (Former: The urge for a twin.)
 

Ordering nut driver set now.. :) And new linkages just to be sure. I don't want them to fail on me!

RE: Hobbico Twinstar minibuildlog (Former: The urge for a twin.)
 

The plane is now finished!:) I've used about 10 hours from start to finish on this project, so it is a very fast build.

I built this plane by the plan as far as it was possible, however I did some things different:
1. Changed all the screws for the engine mount to 4-40x7/8"
2. Had to cut out holes in both nacelle covers in order to make the links/servo move freely (Should have placed servomount beneath skin instead).
3. Twisted the nosegear to improve movement.
4. Some CA hinges were missing, so I used pin hinges on rudder and elevator.

Anything else went according to plans.:)

Pics of the finished plane below!

RE: Hobbico Twinstar minibuildlog (Former: The urge for a twin.)
 

Mine is ready to go. It has OS 32f engines that are just now getting broke in. Really awsome to have two little engines turning 14500 at the same time, wow. I want some good weather and a little more stick time on another plane before it flys. Snowed again this am...sick of the white s-, I think Global warming is a farce. I had over 19 ft. at my house this winter.:(

RE: Hobbico Twinstar minibuildlog (Former: The urge for a twin.)
 

Hi gisi,
Where did you get your twinstar from? I really wish that this plane was available in the uk. To import from the states would cost too much (I have looked into it but my wallet isn't deep enough). I have to carry my Dual Ace for quite a longway to get to our flying strip and a Twinstar would be ideal for my ageing body to transport. Oh well at least I can read about the fun that others are having with their Twinstars and dream....
All the best ...Chris. UK.

RE: Hobbico Twinstar minibuildlog (Former: The urge for a twin.)
 

Tower handles them, got mine at the LHS. Flew it last week and have 9-10 flights on it, fuel management is critical. With the 32's five mins. is all you want to do if you are putting it thru it's paces hard. It really hauls and verticle is unlimited, landings and takeoffs are very basic and easy. You have to watch the plane closly or it would be gone very quickly.:D