SJM 400 V2 - great work of art!

[BarnOwl]

Ok, I got the bird flying today. I used all electronics I still had in my T-Rex drawer: 3 HS 65 HB on the swash, one Airtronics digital tailservo, Telebee RC 500 HH gyro, HDX 450 outrunner, ALign 35a ESC, Futaba 146i PCM rx.
I used an Apex 15C 2100 mAh 3S pack and a 12T pinion, this got me a 2550 rpm headspeed measured with a SkyTach.
Total RTF weight in this configuration is 630 grams.

The bird is rocksolid and very stable! The main blades supplied with the kit are very good, one little piece of tape (1g) was enough to get them balanced. Another thing I noticed is that the blades track as a knife!

Compared to my T-Rexes SE the flight characteristics can be called mild allthough response is good and very smooth. Somebody mentioned slow reaction on the tail but I cannot agree with that. Piro's are fast and accurate.

Now I have only flown it for two packs to test it with the standard configuration. This heli is very good for beginners too.
So far I am really amazed at the price-quality ratio for this kit, at the moment this is the heli to be beaten in that perspective!

Next I will be putting in my JGF 450F motor with the Jazz ESC and first I'll try the 12T and then the 14T pinion. This should give me a headspeed just under 3000 rpm. I will also get rid of the rather big flybar weights.

If it comes through that without breaking apart I'll let you know as soon as I get to that........... :wink:

[bluemooone]

:mrgreen: :noteworthy :mrgreen:

[Sgt_BF_Gunner]

Barnowl,

Don't the Hitec 56's have the funky tabs on them... Looks like the 55's would be the next to fit. Sure would be nice to use 65's without having to modify the mounts and servos... Holes line up too?

Thanks,
Gary

[BarnOwl]

The funky tabs are there to be cut off if you don't need them. Holes line up ok with the 65's. You can move the servo holders to make any servo fit as long as they are not higher than the 65's.

[Sgt_BF_Gunner]

OK thanks. I was going to go for Fung's Premium Combo but I have never heard of TMF-S09 Servo for CCMP and Maxwell Speed Rudder Servo(S2G) for the tail.

I like the Futaba R146ip PCM receiver and Telebee Head Lock Gyro might last me for a while. Plus the package includes motor, ESC and a AP1700 3S1P 20C LiPo.

I believe a great deal for $347 but I don't want to skimp... Was thinking Hitec and GY401...

Thanks,
Gary

[bluemooone]

Alright!!! I just received the SJM400II 3D and I have to tell ya, This Thing is in a class of its own. The swash movement is smoother than silk and so is the tail movement! All in All I really have to say that this 400 leaves the trex is a cloud of Heli dust :mrgreen: Finless....... You really have to see one of these :!: (the pictures do not do this justice! The macheining is outstanding and she looks like a romulan bird of prey)

[WillJames]

Just kiddin', you mean a 450 eehh? Here you go:


HAHAHAHAHHAAHHAHAHA

Good one you had me going man!! :noteworthy :glasses2:

[bluemooone]

Ya ! Me Too LOL :lol:

[BarnOwl]

Just kiddin', you mean a 450 eehh? Here you go:


HAHAHAHAHHAAHHAHAHA

Good one you had me going man!! :noteworthy :glasses2:

Even fooled you, did it? Shame on you......as a new 600 owner you should know better, Will!

[BarnOwl]

Alright!!! I just received the SJM400II 3D and I have to tell ya, This Thing is in a class of its own. The swash movement is smoother than silk and so is the tail movement! All in All I really have to say that this 400 leaves the trex is a cloud of Heli dust :mrgreen: Finless....... You really have to see one of these :!: (the pictures do not do this justice! The macheining is outstanding and she looks like a romulan bird of prey)

So you got it flying too, great! Please post your experiences....
I don't agree that it leaves the T-Rex in a dust of cloud though... it'is a completely different heli, smaller and also more fragile.

I had my first negative experience yesterday: The screw holding the slidebar from the tail came loose. I managed to land the bird without further damage.

I found out that this screw (Which holds the ball connecting the tailservo rod) is only threaded in the tail slider for 1mm. As with the other parts I secured it with blue locktite WHICH IS NOT SUFFICIENT. This parts holds all the force of the tailrotor, and I have been only flying very mild with it.
I fixed it for the moment by putting CA in the hole.

The reason is simply that the screw is too short. There is another 1mm thread there so a little longer screw will hold it. Another thing that makes the construction weak is the 1.5mm spacer between the slider and the ball. But this is needed otherwise the ball will hit the rotating part of the tailrotor.

*edit*
In general I am not to happy with the sloppy tailsetup, this was also mentioned about version1 but unfortunately it has not been upgraded on the V2. The slider causes binding on the ends of travel, that's probably the reason the screw came off. I cleaned and sprayed the setup with silicone and the last flight everything seems smooth again.
*edit*

I wrote Scott about this, I'll wait for his reaction........

[R-4-L]

we have these here in a shop,, I must say the mechanics are WEIRD and beautiful! one horizontal frame holding most of the stuff, and servos it comes with are strong! , tail servo is just a few millimeters away from the rotor blade it self!
nice german design!

[BarnOwl]

Just some pics of the finished heli. All above mentioned T-Rex electronics fit and fly no problem. I painted the canopy just the way it shows on the website cause I like it that way:

[bluemooone]

Very nice. Ya this heli is lighter and maybe somewhat more delicate than a trex. I have not started build yet and was commenting on the smoothness without servos and such. I would have had this built by now I think ,but just finishing the CP 300 conversion. Yours looks great :!: :dance Does it fly as gentlly as I think its going to?

[bluemooone]

Alright! Build done (very easy , came mostlly assembled) and here are a few pictures :D

[BarnOwl]

I like that setup, bluemooone, looks great! I have the ESC and rx on the tray where your battery is, but I like your idea, I think I might try that.
Can you still fit the canopy with that pack way up front?

BTW: Taking the canopy on/off is a real PITA on this bird!

This is my electronics layout:

**EDIT 10-5: Second picture: Changed the RX to the back behind the battery, keeps high power away from low power wires and CG can be changed by moving battery forward EDIT**

[bluemooone]

Yep! plenty of room for body. I have the receiver mounted on the other side . Actually on the side.

[bluemooone]

Barnowl , If you can , ask the SMJ person that you know this : why why why do you have to glue the tail assembly to the boom? I see no other way to tighten this. As for every thing else , It flys like a dream!

[BarnOwl]

Well, the SJM person has not answered my mails for about a week.....either Scott or Ken.
The tailboom glueing has been adressed by a lot of people, but unfortunately SJM did not change anything about the tail on the V2.

[Bud Morrison]

I got both of my sjmIIs last night and checked both the tail boom glue joints and both of them seamed to be quite solid. Gluing the tailboom is no big deal I am used to it from gluing motor mounts on my micro booms they are actually quite easy to remove if you have to change a boom. All it takes is an overnight soak in some acetone.

Someone mentioned playing with the flybar weights. Im going to machine a taper on the backside of mine on my one sjm and see how it compairs eventually I will get around to totally removing the weights and see how that does if someone don't venture there before me :)

[bluemooone]

Ya , this is a minor point I guess on a such a cool heli. What really amazes me is how light it is.

[BarnOwl]

Does someone know where to get pinions with 3.17mm shaft holes for this heli? I have tons of Align pinions laying around, as well 2.3 and 3.17mm but the teeth of the Align gears don't fit: They are much bigger.

I have been looking all over the place. I should find a heli with the same teeth ratio as the SJM. Maybe in the zoom/400 line? Surely there must be people like me who want to get a 450TH or other motor on this bird. A LOT of these motors have a 3.17mm shaft.

At the moment I am using a 3000kv HDX 450 motor with a 14T pinion(2.3mm). I get about 2300 rpm headspeed. So for now I ordered the 16T pinion but for using the popular brushless motors I really need 3.17mm pinions!

[bluemooone]

http://www.mscomposit-usa.com/shoponline/products/electrics/motors.php Here are some that may work.

[bluemooone]

What size are the tail belts? And where can I get one? Also , how do I order parts and pay for them (I have the part/price list)

[PTFlyer]

I haven't used this e-shop........but they do seem to have parts for the sjm400........

http://www.flying-kit.com/index_ecat.php?cPath=54_55

[bluemooone]

I emailed the SJM Link and received a reply `parts you need sent today , please pay paypal` Awesome! , And PTFlyer thank you for the e-shop link as well , I may need a few things from them also! :D