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90mm Jet Discussion - Printable Version

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90mm Jet Discussion - gbanger - 06-08-2011

Hi Paul and Kevin and anyone else tuning in.
I thought I would start a thread so we can discuss ideas and equipment options for the 3 big EDF jets we are all about to start building.

OK I'll start,
I have got most of my equipment now and thought I would let you know what I am using that way we may be able to assist each other with various installation, setup and flight issues.

Attached are some shots of my Platinum Pro 120 ESC and the optional programming card I purchased from Extreme that they reccommended for the Stumax fan setup we are all running. If you guys buy the same ESC you are welcome to borrow my card anytime to adjust perameters on your ESC.
   
   
You will notice in the top photo that there are 2 leads coming out of the ESC.
The long one plugs into your reciever for throttle control the other one plugs into the programming card for touch button program changes.
I am currently looking at a variety of servo options but am leaning toward the Turnigy and will let you know what I deceide.

RE: 90mm Jet Discussion - paulj - 07-08-2011

Thanks Gazz, this will be a very handy thread for all of us.
I have not started to build my L39 yet due to other unfinished projects
but once I get them out of the way I shall be looking towards what
gear I need for this.

RE: 90mm Jet Discussion - gbanger - 07-08-2011

I ordered my servos this afternoon. I have been looking at a number of options but decieded to go for these

http://www.hobbyking.com/hobbyking/store/__8956__Turnigy_555MG_Slim_Wing_Servo_Metal_Gear_4_2kg_15sec_23g.html

They are similar to the Hitec 5125's that you were looking at using Paul but are Turnigy's performance option. They probably come out of the same factory, specs are pretty much identical (although the 555 has a higher torque rating)
I have these in my Hotliner, even though I have not used them yet, my reaserch has found them to be a reliable upper range high quality servo.
The other one I was looking at was these

http://www.hobbyking.com/hobbyking/store/__11627__TGY_390DMH_High_Performance_MG_Digital_Servo_Extra_Strong_5_4kg_11sec_22_5g.html

I would actually prefer to use these but the mounting points on these is not practical in our application.
The manual reccommends the use of these type of servos by taping and epoxying them in position but I'm sorry as far as I am concerned that is a very unacceptable installation procedure. I will be using the 555's epoxying in timber mounting rails and fastening the servos to them with screws..
I will take photos along the way and put together my own build manual, the on line one is crap and really doesn't offer any build assistance at all.

RE: 90mm Jet Discussion - paulj - 07-08-2011

Thanks Gazz.
For mounting the thin wing servos kev and I will be using these.
http://www.hobbyking.com/hobbyking/store/__7024__Servo_Proctectors_Black_Colour_.html
Have seen them in use on rcgroups and they are easy to mount and remove
if you even need to replace a servo.

RE: 90mm Jet Discussion - kizza42 - 07-08-2011

Just on the slim servo's, Don't make the same mistake I did on my Bullet and use analog servo's like those that you listed. Get the digital versions:
http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=8957

RE: 90mm Jet Discussion - gbanger - 07-08-2011

Whats wrong with the Turnigy MG 555's Kieran?

RE: 90mm Jet Discussion - kizza42 - 08-08-2011

Analog...
They never center 100% right, you wouldn't notice with anything parkflyerish but now that you're moving to the better side of 200kph, it'll probably start to annoy you.

My analog hitec 125's never center right, every flight needs retrimming.

RE: 90mm Jet Discussion - ~KevJ~ - 09-08-2011

thanks for listing these servos guys, i wasnt sure what needed for it but they look good for the money..
i too like the idea of going digital.

RE: 90mm Jet Discussion - gbanger - 09-08-2011

O'well looks like I will be doing a bit of in flight trimmimg then, I have ordered 8 of the suckers and they are on the way. My mistake I thought that the MG 555's were digital, I've got 5 of them in my hotliner, will have to see how they fair when I get that airborn.
If you read the literature on them and the Blubird Digitals they are identical in every respect, will just have to wait and see.

RE: 90mm Jet Discussion - ~KevJ~ - 09-08-2011

ahh well , you might be fine gaz , will be interesting to see what you think in the air.

RE: 90mm Jet Discussion - paulj - 09-08-2011

When the time comes I may get those Bluebird servos.
They are $20 cheaper per servo than the cheapest Hitec HS5125 I can find
in Singapore.
Here is Aust. the 5125's are anything from $75 up.

RE: 90mm Jet Discussion - gbanger - 09-08-2011

Buy one and test it yourself Paul, I cant really speak from vast experience, but I bought a top of the line digital Bluebird retract servo for my Trex600 Airwolf, with 12 kg of torque, it wasn't cheap either, It lasted 6 cycles and shit itself with a puff of smoke, I sent it back and they replaced it no problems, that one lasted 4 cycles. What pissed me off was that it took over an hour to get it out and put it back in (tight spot with 3 seperate control rods off the one servo) anyway I threw that one in the bin and replaced it with a 12 kg Turnigy and to this day it never missed a beat. I swore then and reiterate now. I will never use bluebird servos (one bitten twice shy) THEY'RE CRAP!

RE: 90mm Jet Discussion - ~KevJ~ - 10-08-2011

hmm .. noted

RE: 90mm Jet Discussion - kizza42 - 10-08-2011

Also note that Turnigy servos are rebadged Blue birds Wink

RE: 90mm Jet Discussion - ~KevJ~ - 10-08-2011

lol noted also

RE: 90mm Jet Discussion - gbanger - 29-08-2011

Hey Paul
Did you get over to Darrens on the weekend and if so what were Darrens suggestions re mounting the turbine, my best guess is that the thing has to be epoxied (hysol) in on fixed rails in the longitudinal grooves that are there for turbine installation. Cant believe that they have to be glued in.
PS: Turnigy has just released a digital version of the MG555 slim wing servo (the pricks) my analog ones arrived last week (shit). Mind you they aren't cheep. But they are still half the price of the Hitecs


RE: 90mm Jet Discussion - paulj - 29-08-2011

No mate had too much to do on weekend
did not make it to Darren's place.
I'll talk to him on Saturday seeing as Sunday is Father's Day and I'll
be at a family picnic.
Hopefully get a little bit of flying in on Saturday too.

RE: 90mm Jet Discussion - gbanger - 05-10-2011

Hi Paul
How is the L 39 build going, from the look of things on the club forum you have a very busy time ahead of you with all of these airliners etc.
Just thought I would make you aware of something I didnt notice... (I didn't)
The wing tanks are handed.
I was about to do the final epoxy on my ailerons and thought I would epoxy on the tanks to help center the ailerons properly. So I glued them on.
Then when I epoxied on the ailerons I found that the trailing edge of the tanks is feathered to blend in with the ailerons at centre stick. ... Shit!!!
It really isnt very noticable but I know it is there which pisses me off but there is nothing I can do about it now. As I said it is not that big a dael but I thought I would let you know so you dont make the same little mistake I did.
Did you get Darren to look at the Turbine installation... because I am just about up to that part of the build?
Gazz

RE: 90mm Jet Discussion - paulj - 05-10-2011

Hi Gaz
Thanks for the tip.
I hadn't noticed that yet as I've been rather busy lately
what with fixing kev's PC9 and Temora.
Yea Darren had a look at the turbine installation and we worked it out.
Rather I should say he worked it out for me. Smile
You will notice in your L39 that the 2 wooden formers nearest the turbine location are notched.
What we did is glue in there 2 basswood railsthat extend towards the forward end of the plane.
we used 5mm Basswood but we also had to pack a piece of timber on the inside of the notches
to get the rails to sit exactly the correct distance apart for the Stumax.
We found that a popsicle stick is just the right thickness.
When you install the Stu you will then see that it is not directly in line with the inlet tube.
What you have to do there is cut the included inlet adapter at an angle that corresponds with the amount of offset. Suggest you get a piece of cardboard and make a dummy adapter so that you can practice cutting the angle. (It's a bit of trial and error). Once you are happy with the angle cut your adapter the same.
What you will end up doing is slipping on the adapter upside down and loosely mount your Stu to the rails then turn the adapter to the correct angle and you should be able to slid your Stumax forward and tighten. This should then allow you to mate both ends up to the Stu and Inlet Pipe for a flush tight fit.
Then seal with something like fibre tape etc.

Probably easier to show than to describe. I'll bring fuselage along on the weekend and show you what I'm talking about.

RE: 90mm Jet Discussion - gbanger - 25-11-2011

Howdy Expensive EDF Enthusiasts
I have just posted a video on Utube, hopfully helping anyone who is building a Jet Teng model, obviously with the emphasis on an L39.
I will add to my mini documentary as the build progresses.
Hopefully it will help a few people out.
Here is the link

http://www.youtube.com/watch?v=uPHCFatNiQg

Cheers Gazz

RE: 90mm Jet Discussion - paulj - 26-11-2011

Great work Gazz.
Like the tip about heating the Xacto Knife.
If I get the time this weekend I'll do a video of the mounting
of the Stumax and the inlet adapter.

RE: 90mm Jet Discussion - smuzz - 26-11-2011

Nice work Champ! - I'm impressed.
Only one suggestion - next time, get Trude to bring you in a beer just at the end as a sign-off and reward for all your endeavour!

RE: 90mm Jet Discussion - robair - 27-11-2011

G'day All

Nice vid Gazz, looking forward to upcoming episodes.
Quick question, when you join an edf motor to esc do you use bullets or just solder wire to wire?

Cheers
Rob B

RE: 90mm Jet Discussion - gbanger - 27-11-2011

Same as any motor Rob.
Depending on the current draw but I use bullets. The Stumax 90 I am currently installing in my L39 draws a little over 100amps but the manufacturer recommends 4 mm bullets, I questioned him on the size and he said that they are more than sufficient between the ESC and the motor but the bullets I am using between the batteries and the ESC are 5mm bullets (big current draw there, huge.)

RE: 90mm Jet Discussion - gbanger - 05-12-2011

Hi Paul
I would appreciate it if you could take a few pics of your fan installation and drop them on this post.
I am up to the final stages now and would like to see how you and Darren have mounted the thing so I can steal/ copy/ modify your installation so I can finish my L 39.
I hope to have mine ready for maiden just before Christmas.
Iv'e only got the gear and EDF installation to go.
Stage 2 video coming soon.
Thanks mate
Gazz

RE: 90mm Jet Discussion - paulj - 05-12-2011

Ok mate will do.
Will get the photos done tomorrow morning.

RE: 90mm Jet Discussion - paulj - 06-12-2011

Hi Gaz
Here is some photos of my installation.
First off we epoxied in 10 x 5mm Basswood Rails.
In order to get a nice snug fit around the Stumax housing we found
that it was necessary to add an extra piece of timber into each rail cutout
first. We found that a paddlepop stick was just the correct thickness
for this.

   

Next we inserted the Stumax and pushed it as far towards the back
as we could to facilitate the installation of the Inlet adapter.

   

Now you will see that the Stumax and the Fibreglass Inlet ducts are
not quite in line and require you to modify the supplied Inlet Adapter.
Before you stat cutting this adapter I suggest you make up a cardboard
adapter and practice on this getting your angles worked out etc.
This next photo shows my finished adapter. Note how we had to shorten the adapter first then cut an angle on the short piece and bond it to the straight piece.

   

Note that I have also applied some tape(one sided) to the front edge
of the Stumax. This is to provide a seal around the join of the adapter and edf.
The adapter gets inserted upside down into the fuselage with the EDF
pushed far back. Once inserted turn adapter correct way up and ensure
that the adapter snugly fits around the Inlet Ducts.
When happy with fit push Stumax forward into the adapter and screw down onto the mounting rails. This should stop any chance of the adapter moving in flight. You can now seal the adapter/EDF union with
some tape.(not shown)

   

Some things to consider before doing above.
If you are going to install an exhaust tube you had better do that first and attach to the Stumax as it will be impossible to seal it after edf is mounted.
By only sealing the adapter/edf join with tape it will be easier to remove
the edf and adapter if you ever have the need.
Hope these photos help you. I'm looking forward to seeing you maiden her.



RE: 90mm Jet Discussion - gbanger - 06-12-2011

Thanks heaps Paul, very helpful info and pics, cheers mate.
Gazz

RE: 90mm Jet Discussion - gbanger - 12-12-2011

Hello once again from Gazza's Aviation
Here is the link to Part 2 of my Jet Teng L39 build
http://www.youtube.com/watch?v=EJ32_YaJ8oc&feature=channel_video_title
Hope you find it interesting
Gazz

RE: 90mm Jet Discussion - Jungle - 14-12-2011

Nice work Gaz. I am looking at an L-39 composite as my next bird. This will be very helpfulLeet