Mini-Review Walkera #38 large tandem coaxial

[lexip]

Okay, take a look at these two photos from the side. I don't have another one to compare it to so any input is valued. I can see a possible slight bend in the main beam (aluminum) right at the rear wheel bracket. Let me know what you think. The 2nd picture is of the switch I installed, not much but it does make a safer way to cut power if you find yourself in the situation I was in (read previous post). The canopy is so beaten I've decided to replace it. You can see I epoxied the wheels on which has saved a ton of trouble.
If you do use epoxy then make sure you mix it for 30 seconds on a piece of cardboard and a wood stick (ice cream sticks work great). This ensures it sets very strongly.




Picture of my switch just installed, used small zip ties to secure it.


As far as blade strikes, nothing much I know to do but to be gentle on the sticks. I have found a very good deal for a pack of 4 blades for $4-5 bucks at rc711.com. It's a chinese supplier and it takes about a week plus to get blades delivered to the states. I agree that a longer inner shaft would probably solve it but it would probably change the flight characteristics pretty strongly to. Someone posted earlier the idea of using shrink tubing on the base of each blade. I tried it and the blades do last longer but it is a lot of trouble to put one on each blade.

If my main beam is bent then I don't have a clue where to find one at. I've googled it to death and can't come up with anything.... If anyone knows then share the info. thx.......

[Jcopter]

You can find all 38 parts @ miricle mart http://www.miracle-mart.com/store/in...x&cPath=80_191 they have you boom
Jcopter

[lexip]

Thanks!!!!

[Jcopter]

Hey here is a code summer-sale it will get you 10% off just type it in the code box it is good untill Oct
Jcopter

[kwg08]

I’ve had a 38 for awhile now and have always wondered about the flimsy little linkages they use off the servos. I’ve actually had problems with the glue coming loose and the rods slipping in the end.
So I experimented and tried something I think helped tame this big bird down a lot.
I took some 5/32 x .014 aluminum tubing and sleeved all the rods. Really stiffened up those flimsy linkages.
On the links with the long screw, I made the tube extend out onto the rod end to help stiffen that too.
To get the rod ends to fit into the tubing, I had to take some sand paper and sand the hex of the rod end. Make it round and fit fairly snug into the tube. I marked the tube where the rod ends would wind up inside the tube, and then simply took a pair of wire crimpers and crimped the tube on the inside end of the rod end.
In the pic, the red arrow is where marked the location for the rod end and the yellow points out where I crimped it.
I think it made it alot more controllable, and it cost me a whole 2 bucks.
I can't for the life of me get images in my post. I put them on here as attachments.

[darkside212]

anybody program their own tx to use?

is it the same principal as other 4ch where you revo mix the two "rudder" motors and have a gyro on them?

[bigmagoo]

If anybody is looking for a Walkera #38
I have one in the for sale section,good price.

Thanks Steve.

[Chiconc]

I dont see how you can possibly be getting your stock 2200 Mah battery charged in less than a hour on the stock .8 amp charger?????[/quote]

I just bought a #38 Sea Knight and the first charge was less than 2 hours. gave me like 10 minutes or so. So Idk what's going on with either yours or mine.

[Chiconc]

Originally Posted by mikesndbs

Xrayted, really great advice re the arms!

I took it for a fly this morning and it landed on our roof as I had no forward fly ability

Brought it back in and adjusted the arms as you said.
Rear went from 3rd up to 3rd down
Front went from 3rd up to 2nd down.

It now flies great and was described as HARDCORE by a passerby LOL

Cheers mate, nice one

Hey Mikesndbs! I've seen your vids on youtube. I also just bought this helicopter. It flew great the first time at a local park, attracted an 4 year old girl who saw it, ran after it, almost got her hand cut off and so I cut the motor and it dropped... But anyways I've flown it for 3 days now... the last 2 days, it hasn't flown. I need more spare rotors and the darn thing is vibrating A LOT I checked it without any rotors and it nearly vibrate-rolled off the table. Also, the top rotors are losing total power when the rudder stick is pushed to the left. Any help???

[Chiconc]

Originally Posted by lexip

Brought it inside and it came on again in the kitchen, got my legs good and I pressed it against me like the guy did the dog in The Legend movie so the blades wouldn't spin.

Poor Poor Sam I hate that part of I Am Legend lol

[Xrayted]

Originally Posted by Chiconc

Hey Mikesndbs! I've seen your vids on youtube. I also just bought this helicopter. It flew great the first time at a local park, attracted an 4 year old girl who saw it, ran after it, almost got her hand cut off and so I cut the motor and it dropped... But anyways I've flown it for 3 days now... the last 2 days, it hasn't flown. I need more spare rotors and the darn thing is vibrating A LOT I checked it without any rotors and it nearly vibrate-rolled off the table. Also, the top rotors are losing total power when the rudder stick is pushed to the left. Any help???

I havent visited my old thread in a long while, and I see there are still a few of you guys flying these big guys

Chiconic, the way a coaxial heli controls the rudder is by increasing or decreasing RPM on one set of the rotors. If the top rotors slow down the torque from the lower rotors will cause the heli to turn. Its a balancing act of torque between the upper and lower rotors spinning in oppostie directions that cause the heli to spin or stay straight, so what your seeing is normal. The upper rotors will slow to a stop though if you spin up and just let it sit on the floor.
The gyro tells the uppers what to do so you need to get it up into the air for the gyro to start doing its job.

Asssuming you have nothing bent causing the "shakes" you can reduce this by putting dense foam or something wedged in between the fuselage to absorb the resonace that causes this(see below). I noticed when I had mine that these vibrations never happened if I flew with the body off, so its resonance from the body that causes the wierd shudder that will start in flight. You did crash though so you need to verify that you didnt bend you main shafts or flybars causing your vibes

BTW the stock charger rate is way too low for the 2200Mah battery and takes a long time to charge. The proper rate for that battery should be at least 2 amps not .8 with the wimpy one supplied. At 2 amps its takes just over an hour to charge a depleted pack........more than double that with the stock charger. All Walkera did was throw in a charger from one of their other smaller helis rather than provide one purpose made for this heli and battery

Happy flying

[mikesndbs]

Hi everyone, sorry I have not been around for some time.
I am sorry to say this will carry on as my wife passed away in August aged just 50! I am 44.
Its hit me very bad as you can imagine, we were so very close.
In fact she did the filming for my videos and can be heard on a number of them.

I still have the helis and one day I guess they will go for a fly.

I can't really add anything at this point that I have not covered in my videos.
http://www.youtube.com/user/mikesndbs
If you go here and look at my play lists you will find them all.

Vibration comes from the inside struts not being in place properly or blade balance.

Regards

Mike

[Xrayted]

Originally Posted by mikesndbs

Hi everyone, sorry I have not been around for some time.
I am sorry to say this will carry on as my wife passed away in August aged just 50! I am 44.
Its hit me very bad as you can imagine, we were so very close.
In fact she did the filming for my videos and can be heard on a number of them.

I still have the helis and one day I guess they will go for a fly.

I can't really add anything at this point that I have not covered in my videos.
http://www.youtube.com/user/mikesndbs
If you go here and look at my play lists you will find them all.

Vibration comes from the inside struts not being in place properly or blade balance.

Regards

Mike

Mike I just want to say I am so sorry for your loss. My Father passed at age 43 and I just lost my best friend 2 weeks ago at age 41, so I can understand to some small extent. Good luck Mike and God bless you

[Jcopter]

Oh Mike I am so sorry to hear about your wife
do what you need to do
My prayers are with you
Jcopter

[Chiconc]

Originally Posted by Xrayted

BTW the stock charger rate is way too low for the 2200Mah battery and takes a long time to charge. The proper rate for that battery should be at least 2 amps not .8 with the wimpy one supplied. At 2 amps its takes just over an hour to charge a depleted pack........more than double that with the stock charger. All Walkera did was throw in a charger from one of their other smaller helis rather than provide one purpose made for this heli and battery

Happy flying

So is it safe to buy another, more powerful charger and charge the battery with that?
And thanks for the tips! I need to buy some more rotors, so its grounded for now but I'll make some foam shock absorbers and stuff.
-Chiconc