[phil485]

Hi all,

I thought I would start a new thread as there was some discussion on my what motor thread that may have put some people off. I will try to cut and paste some details from the old thread here.

So what have we got.....

A brand new Sbach kit from Global RC in the great orange scheme, beauty is in the eye of the beholder 

I decided to go electric with it and will be using two series linked 6S 5000 packs to make 12S. This is a size of pack that I'm currently using  and I'm happy  to get more.

I have managed to aquire a Hacker A60-18L for motive power and even got my hands on an APCe 24 x 12 prop.

The plan is over the coming months to aquire savox servos all round and a hobbywing esc.
I am currnetly thinking  of powering the radio using two 2S lipo's ( mainly because I've got them) running through regulators into a Futaba 617 reciever.

[Alan]

Is it done yet

[phil485]

Start off as we must with ......

The box!!





I already had a little play while at work but this is the insides. Usual sort of packaging and everything looks pretty much safe and sound.





Most of the big bits laid out. I noticed a small bit of damage to the canopy when at work. I'll get some pics later. Nothing  cosmetic and easily fixed.





Up on her wheels, the nuts aren't done up but just wanted to get a feel for the size. The legs seem to be pretty heavy duty and should stand up to my arrivals.  Thick Ali (??) doublers built into the fuz for the mounting too.






Wings and tail feathers in. The sheer size really comes out now. This is my first 50cc size. Previous largest was a funtana 90.

[phil485]

Images haven't come across so I will reset them later.

not done yet Alan, SWMBO hasn't approved the spend for the servo's yet ! 

[Alan]

Looking forward to this one, need a test pilot

[phil485]

I did get a chance to have a bit more of a play today though.

A few more pics.

Got the bench tidied up and ready to play. Still got to finish off a mosquito, small extra 260 and an SU 26 but I needed to play with my big toy.



I was asked about the undercarriage fixing. You can see here the ali plate inside the  fuz. It's all tied in nicely, it's just going to make a real mess if the landing is really hard




Next is the damage to the canopy in transit....  The rear most bit of foam board was loose ( possibly left that way so you can easily add a pilot) but the fixing lug on the canopy had broken free. the bit of foam board meat the canopy wwasn't sitting in the correct place and that had put the extra stress on the lug.





Trial fit of the hacker and mount. All went together great and looks really lovely. I'm used to turnigy motors and you can see the step up in quality. I also took the time to investigate the carbon spinner that comew with the kit.



 
This is where the problem comes. The locknut on the hacker power set isn't big enough to take the bolt from the spinner. Will need to do some investigations to see if Hacker / West London Models can do a differnet  nut with a larger thread?

[Alan]

Looks like the spinner bolt is too long? You do have both nuts on the shaft don't you?

[phil485]

spier bolt is a bit too long but also too thick. think it's m5 but the internal thread on the hacker bolt is m3

[Simon Wood]

Yes - it will be 5mm as internal thread on a DX(X) engine is 5mm to take the spinner bolt.

Oh, and subscribed 

[steamysheep]

What a smashing looking plane.. Subscribed.. 

[Alan]

spier bolt is a bit too long but also too thick. think it's m5 but the internal thread on the hacker bolt is m3

That's a pain. I know there is not enough material on the Hacker nut to tap to M5. How about using an M3 bolt, and just sleeve it to fit the spinner?

[Doc Take 2]

Awesome I just ordered one yesterday, i wanted the other scheme but orange is all that they had but it looks mint on here.  I'll be fitting my 3w50i to her and a real cheap 'install' with tower pro 996mg's I have lying around.

Good luck with the build

[Simon Wood]

That's a pain. I know there is not enough material on the Hacker nut to tap to M5. How about using an M3 bolt, and just sleeve it to fit the spinner?

Or if you have access to a lathe, turn down an M5 bolt and thread it to M3 (you might want to soften it first !).  You can do this with an electric drill and a diamond file if desperate.

[phil485]

Both are very good ideas. Not at home at the moment but will have a proper look at my next opportunity.

[phil485]

I'm on my holidays at the moment so what little progress there was has now stopped.

The undercarriage is all fixed and in place. I like the use of the thin metal rod and ball link to give some shock resistance.

Motor is installed and cowl is in place. I had an investigate and the hacker prop adaptor thread is M4 and the spinner bolt is M5. I was struggling to find an M4 x 85mm bolt so I may try to turn down the M5 bolt that came with the spinner.

[phil485]

Forgot to say spinner currently held on position with a piece of M4 studding.
Pictures and last post were done on my phone so quality may be shocking.

Hope to order servos on Tues/ Weds so they turn up later in the week.

[phil485]

I was about to place the order for the servo's just a minute ago but I thought I would do a quick sanity check on here first...

I've heard good things about the Savox servo's and the prices seem ok, so I was going to use.

1 x  SC1256TG on the rudder https://secure.servoshop.co.uk/index.php?pid=SC1256TG&area=
4 x  SC0251    one on each elevator and aileron half https://secure.servoshop.co.uk/index.php?pid=SAVSC0251&area=

What do we think??

[Sizzling]

I was about to place the order for the servo's just a minute ago but I thought I would do a quick sanity check on here first...

I've heard good things about the Savox servo's and the prices seem ok, so I was going to use.

1 x  SC1256TG on the rudder https://secure.servoshop.co.uk/index.php?pid=SC1256TG&area=
4 x  SC0251    one on each elevator and aileron half https://secure.servoshop.co.uk/index.php?pid=SAVSC0251&area=

What do we think??

I have 5 of the 1256's and they are imo one of the best quality servos of that spec, better than the JR equivelents at nearly half the price. Incredibly accruate (4096 bit and all 2.4 gear only operates are 2048) and the titanium gears dont suffer from increased slop over time like others, or at least mine havent after 18 month of use on a 50cc petrol with lots of hours on them. I know some people using the JR's change the gears once a year because of slop  

I think yours are a very good choice for an electric model as the 251's will give a faster response.

I know people using Savox in F3C/3D helis and jets now that swear by them  

[Alan]

Servo choice is fine Phil. I use the 0251's on the ailerons of the Extra, and that's a few pounds heavier than your SBach is gonna be. Savox are quiet and so far seem excellent value.

[phil485]

cheers guys,

all ordered now. will they arrive tomorrow I wonder 

[Alan]

If they do, test flight Monday?

[phil485]

Alan,

thought I replied via my phone earlier but here goes agai 

If you've got an esc, y lead for joining the batteries and regulator I can borrow then I will be there Moday. 

SWMBO knew I needed servos, just not the other bits and pieces. Will have to sneak them in over the next few weeks 

[phil485]

I've always used Deans up until now but Alan has recommended EC5's. i like the look of them but is there any real advantage.

Including the sbach my 6S packs are used in three models. Is it worth changing over the connectors?

Also Alan, you mentioned using a shorted EC5 as a final switch. Where does this sit in the circuit? Is it plugged in externally? If it has to be plugged in then the canopy fixed in place then I'm struggling withthe advantages?

Are you flying tomorrow ( Saturday)?? bringing any of your big ones up? 

[Alan]

No flying for me today, apart from the wind, I have had vertigo all week, so no driving. First day today off the medication, hopefully fit for Monday flying.

Right, EC5's. Unless you are using genuine Deans which are rated to 70A, then the copies are only really good to about 50A. You will be doing more than that. The Hacker on 12S and a 22x12 is doing 66A in my Extra, the 24x12 will see that up in the 70A's.

EC5 are far cheaper than genuine Deans, and will be happy at over 100A.

The shorting plug. Bear in mind how much power you are dealing with in this model, circa 4kW. The potential for damage is massive, so you need a quick way of making the model safe for bringing it back to the pits. Fitting a quick release catch on the canopy as per most of your smaller models is an option, but it needs to be very secure, and it also means you being on the strip removing said canopy to access the connectors. The best solution is the shorting plug.

So, how?

It's all done on the battery side of the ESC. The negative side goes straight though to your battery connector. The positive side goes into one pin of your EC5 socket, with the other pin being connected wia a short length of wire to the battery connector.

So now if you connect your battery, the esc is not live as there is a break in the positive supply to the ESC. To make the model 'live', you plug in a shorted EC5 making the circuit.

I have mine fitted in the side of the extra, I'll go get a pick, back in 5.

[Alan]

Pics.

The 2 connectors on the right (numbers 1 & 2) connect to the 2 off 6S lipo's. The one on the left to the ESC.

[Alan]

This one shows the shorting plug in place, and if the lipo's were connected the model would be live.

[Alan]

And finally, the model 'safe'. Even if the lipo's were connected, the motor would not be able to start as the ESC has no positive supply.



Hope that makes sense. I have mine fitted in the side of the fuselage for easy and quick access.

[phil485]

Cheers Alan,

I might see if I can get down on Monday. Let me know morning or afternoon.

Servos have arrived and fit into the holes nicely. Should get them in place tomorrow.

Just waiting on a few items and need to get some cash together for an esc.

Flying today didn't help. Spent this evening rebounding the engine on my black horse twister. My funtana 90 also needs a lot of work after hitting the ground. Found out what may have caused my funtana crash a few Months ago as well. Basically intended up pancakeing the funtana in as it wouldn't pull out of a dive after a spin. Found one elevator half trapped in a full  down position under the rudder horn. Doh, mental note to cut off the excess.

[Alan]

I'll be out Monday morning, about 10 ish.

Always a good idea to check for binding at full throws will all controls crossed, avoids things like that

[phil485]

Alex,

Did you set yours up as per the manual?? CofG and throws etc?

Have you put in any mixes for different flight modes?

[phil485]

Well Progress is still slow.

All servo's are in and i've programmed in dual rates, ailivators and flaps. Not sure if I will ever use the last two but they came as free as I coppied the settings from my Limbo dancer as a starting point and they were there.

What little progress beyond that is as follows.

I have purchased a Flight tech regualtor, but can we see what happened   



Yup thats right the wrong one was picked and sent by the shop. No worries it's all sorted now and I have the 8 amp on order. I can use the 5 amp in my funtana so it's not all bad

I have ordered a couple of new lipo's and some long servo extension leads from United hobbies but unfortuately they have bee caught by customs and I'm waiting for the letter telling me how much Parcel force want to rip me off for clearing it.

A seperate parcel that has arrived is this though



A whole load of EC5, some wire and the biggest bottle of threadlock I think I've ever seen. This will give me a fair bit of work resoldering all my 6S lipo's and related esc's. Will also need to make up some charge leads for my chargers. I also have all the bits to make up my series harness. I would like to take a proper look at Alan's stuff, but the weather has been horrid whenever we have bee due to fly.

I did have a quick play with C of G based on what I've got. ( Biggest missing bit is the esc, which will add some nose weight) It would appear that the lipo's need to be stuffed right into the ose of the plane, which is going to make securing them horrid.  It will need some more investigation when I have some more time and  a bit more space. The velcro ties are for securing the tank when it's petrol powered and I had hoped to use them to secure the Lipo's. I'm struggling to believe that a 50cc engine is that heavy.... 

   

[Alan]

Getting there Phil.

Re the lipo's going right in the nose. Standard problem. I made a slide in tray for my Adrenaline, so I secure the packs to that, slide it into the nose and secure with a single M4 nylon thumbscrew, works for me.

[phil485]

Aaah, not just a pretty face    


The EC5 plug that is in your fus for your safety switch. Is that just a hole cutout, reinforced and then a standard plug glued in place?

[Alan]

Aaah, not just a pretty face    


The EC5 plug that is in your fus for your safety switch. Is that just a hole cutout, reinforced and then a standard plug glued in place?

Yep.

[phil485]

Well,
look what turned up on my desk this morning.



Nothing stopping me now except for confusion.

I thought there was supposed to be another smaller Black wire for the anti spark?
Is it missing or am I missing something?? Also how do you connect up EC5's with just positive first then negative??
Whats all the gubbins on the positive lead??
Also need to solder up the Y lead for series, I like Alan's safety plug but struggling with finding somewhere suitable for it on the Sbach. 

[Alan]

With EC5 you cannot connect +ve and -ve seperately, both go in together. The comment about connecting -ve first refers to connecting the small anti-spark lead first.

I notice you have the HV 120 esc, mine is the HV 100 so may explain the difference. I think the gubbins on the +ve lead may well be the anti-spark.

I wouldn't worry too much, just set it up minus prop and try connecting the esc, if you get a healthy crack when plugging in you may need to address it or the EC5's will only last 30 flights or so.

2  radio leads, the short one is for the program card (I just set up on the Tx), longer one connects to throttle channel.

Re shorting plug. Mine sticks out the side, looks f.ulgy but the model is no glamour queen. Needs to be somewhere easily and quickly accessible so that the inevitable 'helper' fetching the model can remove it...

[phil485]

Well Soldering will commence tomorrow unless I get some negative feedback on here. 

After way too much head scratching thinking and a good brain storming session with Alan, my current plan of attack for the shorting plug / series harness is this!!

As can be seen on the picture above the positive lead of the ESc has a built in anti spark wire and large bullet connectors. ( you can just make out a break in the heatshrink.) The small anti spark wire is in one piece and will always be live even if the bullets are disconnected!

The gold connectors will be replaced with the large end of an EC5 and this will be the shorting plug which will be mounted facing out of the aircraft. The rest of the series harness will be made up as normal.

So to start up:

Canopy off
Remove shorting plug
connect batteries to harness
connect harness to ESC
Canopy on
Wheel to strip
insert plug  ( then fully live)


On landing do the reverse.


The issue/ concern is that for a while there will be current going through the small anti spark cable. Will this normally be an issue???  I know the motor is not completely dead but if for example I were to stumble and push the throttle forward then the current would go throughthe small wire and burn that out before it did any damage.

Any Comments??

[Peevie]

With the shorting plug removed there cannot be any current going through the small anti spark wire as the circuit is not complete.  In other words until the shorting plug goes in and connects the ESC minus to the battery minus, no current can flow through battery, ESC lead, or anywhere. 

I think your proposed procedure is fine, except I'm not sure why connecting harness to ESC is part of the hook up procedure, surely you'll leave this connected all the time?  Also, it would seem safer to me for you to make your procedure to only ever connect the shorting plug at the flightline and disconnect it at all other times.  Reading the above it seems you expect the shorting plug to be in place before you connect the battery, ie. that you replace the shorting plug once batteries are removed.  Might remove a potential source of error if you avoid doing this.

Sorry I've not been around this thread since the beginning, it's passed me by a bit.

[Peevie]

Ok I read your post again and I think I get it now.  You're suggesting to connect ESC negative direct to battery negative and to connect the anti spark lead direct to battery positive but to insert the EC5 shorting plug as a break in the main ESC positive wire.  Not a bad approach I would say, it allows you to replicate the normal use of an antispark lead on an ESC, ie. connect antispark first, allow ESC capacitors to charge, then connect main lead.  The drawback as you say is that throttle must not be opened even a click or two as this could destroy the antispark lead.

Might be worth mixing your throttle through a switch channel so that with the switch off throttle is zero even if the throttle stick is moved.  Make sure that throttle doesn't go to full with the switch in the other position though!

[phil485]

Cheers Peevie,  that's what we were thinking. It's that or not make use of the anti spark. I'm used to throttle hold on my heli's and it's something I had considered.


Let the soldering commence!!