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#1 FlyDave Mar 25, 2012 02:26 PM

Flight Model Sbach 342 (ARF balsa)
 
1 Attachment(s)
Hi all !

I start this thread to show the building of my freshly received Sbach 342 made by Flight Model (www.flight-model.com)

This is a picture of the finished product, found on the producer website.
Attachment 4734287

Some technical info's :

Name: Sbach 342 55" EP
Numbers: M082
Wing span: 55"/1400mm
Wing area: 38.14sq.dm
Length: 53.4"/1357mm

You can find this model on Hobbyking or others online shops.
I bought mine from a local Swiss supplier.

I'm waiting the electronic parts, so don't expect a finished build so fast :)

#2 FlyDave Mar 25, 2012 02:45 PM

5 Attachment(s)
Ok, starting !

I begin with the landing gear... the easiest part :D

The landing gear is made in black painted alluminium, fixed with 3 allen screws on the airframe.

First picture show the parts contained on the bag :

Attachment 4734303

The wheel support (sorry for my english translation) is fixed on the LG only partially, first thing to do is to mount the wheel. I've added two washers, because i don't like a direct contact between the wheel and the support axle, the picture show what i mean :

Attachment 4734304

Try to fix the wheel stop collar with the screw in the up direction, you may need to adjust it later.
The wheel should spin freely, but without much "play".

Next step... put the wheel cover.

Attachment 4734305

To tighten the nut, simply put a small screwdriver on the small hole, on one side of the wheel axle.
It is not necessary to align perfectly the cover now, you can do it later ;)

Attachment 4734306

Do the same thing on the other side, and... tadaa.. a completed landing gear :D

Attachment 4734307


p.s. : btw, sorry for my english.. i try to correct my grammar mistakes when i find them eheh.

#3 FlyDave Mar 25, 2012 03:01 PM

5 Attachment(s)
Next step, vertical stab.

First i put the stab on is slot, then i mark the position with low tack adesive.
Another trick is to put the adesive on your jeans a few times, if you don't do that, the risk is that you damage the oracover when you remove it.

Attachment 4734347

Do this on each side, then remove the stab and with a small blade cut and remove the oracover, best if a little under the marked position (2mm is enough).

Attachment 4734348
Attachment 4734349

Attach this part with wood glue, it is perfect for balsa vs balsa.

A note : the part show a little gap when mounted, you can fix it with a sander, or you can leave it as it is, it's up to you.
The important thing is to check that when glued, the vertical stab should be aligned with the airframe, as shown in the last picture.

Attachment 4734350
Attachment 4734351

#4 FlyDave Mar 25, 2012 03:39 PM

4 Attachment(s)
Next thing i can do while waiting for the remaining parts, is to glue the ailerons on the wing.

First i glue the cyano hinges on the wing. Using thin Zap with the extender tips allow an easy application of the glue exactly on the center slot of the hinge.

Attachment 4734473
Attachment 4734474

Once done that, you put the aileron, checking to have the same gap (the smallest you can) on the whole lenght, and also be sure that the root of the aileron don't touch the wing, leave enough gap to move freely.

Attachment 4734475

An easy way to find the hinges position, and the point where to put the glue, is to bend the aileron and put a lamp behind, you can clearly see the hole as in this picture :

Attachment 4734476

After the cyano has dried, move the aileron and check for free movement, then if you see a little white fog on the oracover, remove it with a rag and alcohol.

#5 FlyDave Mar 25, 2012 04:04 PM

Horns
 
4 Attachment(s)
Glueing the aileron and elevator horns.

Be careful, on the bag there is 2 sizes.
The long horn goes on the ailerons, the smaller on the elevators.

Attachment 4734508

The carbon fiber horns surface is shiny, you must sanding it a little with sandpaper, so the glue grab better.

Attachment 4734509

The little G10 (fiberglass) plates contained in the kit is glued to the horn with thin cyano.
Caution !! this is my first mistake !

Attachment 4734510

I've only late discovered, that on the kit there is only 4 plates, two for the rudder horn, and two for the ELEVATOR horns !!
It was too late when i discovered, but it is not a problem, i've used a 0.30mm fiberglass sheet and cutted two more myself (see later).

Ok, the horn with the glued plate is now glued with 5-min epoxy to the ailerons.
Check that the glue cover the sides of the hole, and the horn, then push it inside.
Remove the excess resin with rag and alcohol before it catalyze.

Attachment 4734511

#6 FlyDave Mar 25, 2012 04:14 PM

Elevator horn
 
4 Attachment(s)
On the elevator now.

As said before, i've made a mistake using the plate that goes on the elevator horn, on the aileron.
So... the first thing is to build another.

I've many fiberglass sheets on my drawers, so i've taken the smallest (0.30mm thick) and cutted two more plates with an xacto knife.

Attachment 4734541
Attachment 4734542

Do the same thing as the aileron horn. Sand the surface, glue the plate with cyano.
Find the horn hole on the elevator using a lamp behind the oracover (sorry for the bad quality picture)

Attachment 4734543

Cut away the oracover, only on the bottom side of the elevator!
At this point, use 5-min epoxy and glue the horn on the hole.

This is the most important place of your aircraft ! Check that you really put the glue on the hole sides, on the horn, and that the whole assembly is well placed.
This part should never break! If you lose the aileron or the rudder you can still save your airplane, if you lose the elevator you lose the airplane and you can injury someone. Concentrate on the elevator assembly, really.

Attachment 4734544

#7 FlyDave Mar 25, 2012 04:16 PM

That's enough for today.

I've checked the tracking nr. of my order, engine and esc should arrive tomorrow, but the servo's aren't shipped until now... have to wait.

#8 gewiens Mar 29, 2012 11:38 PM

Your gonna love this plane. I must have 30 flights on my HK one and it just handles awesome.

#9 FlyDave Mar 30, 2012 01:48 AM

Quote:

Originally Posted by gewiens (Post 21183397)
Your gonna love this plane. I must have 30 flights on my HK one and it just handles awesome.

I'm sure gewiens, it look very well built :)

Engine, ESC, batteries and propeller arrived today ! will continue soon this build-log.

#10 3d3dman Apr 01, 2012 02:33 AM

flying my sbach in the next 2 hours, cannot wait! FlyDave - I am sure you will know this but please remember to reinforce the elevator- I have after reading all the posts on this model..

#11 Evan03 Apr 01, 2012 08:56 PM

how did it go, im interested in this model

#12 FlyDave Apr 03, 2012 08:45 AM

Motor mount
 
4 Attachment(s)
Just a little update...

Someone on HK review, said that the G60 motor just "fit perfectly" on this airplane.
Well.. this is totally WRONG :mad::mad::mad:

The motor is too big to be used with the original mounts, as you see in the first picture, i have mounted the engine with the aluminium cross, and the propeller shaft is pushed all the way back.
It stick out tooo much to be used with a spinner with backplate.

Attachment 4756056

So i tried to gain some mm (inches) from the front. Removing the "cross" i gained 2mm, and the motor was mounted directly on the firewall using the center holes already existing, you just need to enlarge the holes a bit to fit the 4mm screw.

Attachment 4756060
Attachment 4756057

I have used 4x16mm screws + spring washer + flat washer.
This is a picture of the backside, sorry for the bad quality.

Attachment 4756058

Another 2mm was gained, shortening the motor shaft with a dremel.
Now it's a little better, but still not enough for a nice "zero gap" fitting with the spinner.

Sorry but i was so angry that i haven't taked other pictures after the modifications.

A better mod is to shortening the nose as gewiens has done, look at his thread.
But actually i want to fly this thing soon, before the rain of May, so i will fly it as it is, and will think about better mods in the future.

Tomorrow i should receive the servo's so i can continue.

#13 FlyDave Apr 03, 2012 08:50 AM

Sorry but something does'nt work with my images... they don't scale down automatically....

#14 gewiens Apr 03, 2012 08:53 AM

My plane is holding up perfect with my mod. It's stronger than stock with all the extra bracing I put in. Not sure why the made motor box so long.

#15 FlyDave Apr 05, 2012 11:27 AM

Grrrrrrr.....:mad::censored::mad:

Today i received my servo's.

I don't know who is the i*iot who has suggested those item's on HK, but they are totally wrong !!

The servo's are too thick and they don't fit the elevator mounting holes, nor the aileron's holes that are 25mm thick.
Another bunch of money gone to the wc....:mad::mad:

I can't find servo's that have the correct size and that fit the thickness, so i think i must modify the holes making some adapters and using smaller servo's.

Now i remember also why i hate those damn ARF's... you have always something to modify to make it fly..

I'm sorry but i can't update this thread until i find a economical solution, i have already spent too much for this thing.

Another lesson learned : NEVER thrust your vendor (especially chinese ones..)


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