Sbach 342

[simonh]

I've ordered myself one of these......

http://www.globalrc.co.uk/sbach-342-137-p.asp

The Acromaster is doing its job well as a trainer for something bigger, not foam and more like a 'real' plane. So - time for a crissie pressie to me from me 

It will be electric - of course - running on 6S. I have 9 x 6S 5000 packs so might as well make use of them. I'll post details of the power train etc when I start to put it together.

Servos will be Futaba S-148 all round and  S-3010 (loads of torque)  on the rudder

Some of it will be done with Gareth's help - ie the areas I'm most likely to screw up such as alignment!

[Raj]

That is good Simon! I believe Titu also has got the same model but with engine.

[Gareth]

Saturday morning flying with Global rc sbach 342 3d70

[andyb]

That *does* look quite nice. Would be most interested in seeing that fly...

A.

[Swale]

Very nice simon , when is this beast due at the patch?

[simonh]

mmmm not quite sure. It should be shipped out today. It's not a huge job to assemble it. Its going to depend partly on getting some time with Gareth to do some of the trickier/more precise bits.

I want to strengthen the motor mount and maybe a couple of other areas with triangular stock. I'd like to assemble it to as high a standard as possible so it flies well and as I'd like to take my 'B' with it eventually.

Possibly before xmas, if not then early in the new year.

[Swale]

good good look forward to this one

[simonh]

I've made a start on this - thread is running behind my progress a bit but I'm takng photos as I go.

First impressions of the kit are good - especially at this price. Pre-assembly and covering looks to be to a good standard and most of the servo holes are pre-cut along with the slots in the fuz for the pull-pull cables for the rudder servo.

I'll be adding some extra triangular stock to the firewall area for added strength. Gareth had a look at the undercarriage mount area  - typically a weak poiint on these ARTF's and commented that it had a stronger construction than similar models

The instructions are OK if you have assembled a plane like this before or if you have some experience with assembling / building. For me, the only other model I have assembled like this was the Magic and this had idiot proof step by step instructions. The 'manual' that came with this is basically a collection of poorly lit photos some symbols a few diagrams and some random text. I would suggest getting the assistance of someone with experience of building and assembling if its your first model of this type.

The motor I've chosen is a Turnigy G60 from Hobbyking. It's a 400kV motor. I'll be running it on 6S. Prop will be a 16 x 10. This should give around 1.2kW. Titu has also used this motor and thought it was very good for the money.

Flying weight should come in at around 5.5lb. This will give me around 218 W/lb which should be sufficient.

http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=14405

Speed controller is an 80A Turnigy Plush
http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=3727
It's a little higher power rating than needed but I wanted a decent margin over the max current taken by the motor.

Servos as previously posted are Futaba. The S3010 is ballraced and has 6.5kg of torque -to operate the pull-pull cables on the rudder. The S-148 are 3kg and are more than enough for the other surfaces - which use ball linked pushrods. Servos were purchased second hand from Gareth from his vast stocks of various RC parts.

I've mounted the servos in the wings, hinged the ailerons and fitted the ball link push rods. Tail plane has also been aligned and glued with Gareth's help. This is definitely best done as a 2 person job IMO. I'll post up more detail on this along with other progress so far along with pictures on the next post.

[Swale]

Piccies Piccies Piccies 

[simonh]

Piccies Piccies Piccies 

Some pics 

Wings and ailerons ready for hinging



Aileron servo leads held by a loop of tie-wrap superglued into the inside of the wing. This prevents servo leads from getting lost inside the wing. (no prizes for guessing who gave me this tip  )


Hooligan rates definitely available...


Tailplane glued into Fuz with 30-min epoxy after getting it aligned. This involved an ironing board, a metal tape measure, plenty of eyeballing and a 2200mAH lipo......


The firewall and undercarriage mount areas. Pretty good though will add some more triangular stock for extra strength.

[Swale]

planes like this make me fancy planks again 

[mike.hibbert]

So fickle, Mark...

[Swale]

noooo im still very heli but that is a proper aero....

[Mike S]

Simon.

Nice looking machine. I've never fancied an acrobat type aircraft before apart from the one I am getting off Gareth but this looks very very nice.

[simonh]

This didn't end up being much of an assembly thread I'm afraid.... Its finished and all being well I'll be maidening it up at West London today.  I'll bring it to the patch when I think I can land it smoothly and slowly and consistently enough to not rip the undercarriage out on the bumps.

The covering did need some ironing in places but on the whole it was pretty good.

I'll take some pics of the complete plane once I've put it together up there and post them up.

There are a few pics with comments below. Also a couple of questions - based on comments made on other build threads.

The control lines to the surfaces are mostly short using control rods and ball links. The rudder has a long pull - pull and for this reason I used the ball raced S3010 servo here. I thought that due to the tension on the cables, that a ball raced servo would be better here. Do others tend to use better servos on cabled control lines?

I do understand the need for a decent elevator servo - currently this is an S-148. I think this will be OK for now but maybe it would be wise to upgrade this fairly soon to the equivalant ball raced version?

Any comments on the above most welcome

Battery bay - reinforced with extra triangular stock. I Have since removed the horizontal spar nearest the bay for get the battery in easier and added more reinforecment either side to compensate.


Showing where I put the receiver and satellite and the pull pull cable arrangement for the rudder


A portion of the underside of the cowl cut - away to aid air flow and cooling for the ESC. The ESC is attached to the side of the firewall with a cable tie


Wing bags made from the lined bubble wrap Tim left for us to use in the container. Thanks