Logo xxtreme pictures

[dahld]

No need for another picture. What you see is actually two shaft collars being used together. This is prototype.

When we first got he XXtreme, it came with one collar, with one bolt through it (like the 600 is now, but larger). We found during the prototyping process (that's why we prototype), that when the heli performed a forward flip "wall stop" from high speed flight, the collar would not hold the g-force weight of the heli, and would drift on the shaft. No amount of "tightening" would fix the issue.

The temporary fix was to just add a second collar, which worked perfectly. This is what Kyle used all of 2011, is still on the heli today, and is what you see in the pic.

The production collar will be big and tall like the doubled-up single collars, except it will be a one piece unit, but still using two bolts.

Hope this answers you question.

Edit/add: As guys look closely at the pic, you'll notice the main gear and tail drive belt look well used. That's because they are. They are the original belt and gear installed on the heli (in it's prototype form), back in April of 2011. They have survived countless flights and several crashes. The drive system is very tough, and is showing no signs of needing replacement.

(-: Dave

[lunohod]

Originally Posted by dahld

@ Jays200,
...Kyle has run his XXtremes using only the Western Robotic 14S Super BEC's with no buffer packs etc. We've had 100% performance from the units all year...

(-: Dave

Dave, what is the voltage setup of "Western Robotic" 8.4V ?
And what is the servo's life of Kyle helis?

Thanks

[dahld]

Here's a couple of pic of the production frames all finished-up and test flown.

Note the metal servo arms to see if they make any difference in flight performance (they are new with the build of the frames, but not because there were any problems with the Mikado arms), and the bridge on the boom supports is homemade and new as well, just to see??? Neither are of Mikado's doing.

Edit/add: One other thing. The main shaft on the heli is still a prototype length. Production will be shorter.

(-: Dave

[4cyclic]

this heli is so beefy, bet Mikado had in mind bigger than 800's blades in future...

[jhheli]

I see less wires and no fans, are you running now just esc and bec with no fans or no additional lipos? If so is it not needed because of the heatsink or because it is cooler in your area? also is the production version lighter or no ?

[dahld]

@ jhheli,

The frames make it easy to hide wires if you want to take the time to do so (-:

As for the cooling fans we used to run in the early days. The fan on the motor was mostly to cool the motor as quick as possible BETWEEN flights, during all the back-to-back flying Kyle did to prepare for the XFC and the 3DM. It's not needed to keep the motor cool during use (although we did run it during flight), but just to shorten post flight cool-down.

For general flying, when you normally have some time between flights, it's not needed. I've taken the same 12V computer fan and mounted it on a base with a small 3S lipo, that I can put on and take off the heli to cool the motor between flight if I see the need. But since the high volume flying of the competition season is over, it never gets used.

As for the fan we used to run on the ESC. Back then the ESC was not heat sinked, we were trying new power systems and set-ups all the time, it was in the summer, and not all systems we tried ran "cool". So to keep things going and in the game until we waded through the issues, it was easiest to just add a fan, and keep going.

Once we got a power system and ESC software dialed-in, and the heat sink on, the fan just became extra weight...so off it went.

Not much weight change between the prototypes and the production versions, although we don't own a decent scale (other than a "spring type" fishing scale that varies about a 1/2 pound every time you use it) (-:

(-: Dave

[Big Fil]

Oh man that heatsink came out nice!!

[Aaalie]

Originally Posted by dahld

@ Aaalie,

Yes. The motor remains bolted to the top ... motor can come apart while still bolted to the mount.

(-: Dave

Thanks Dave.

Can you maybe tell us about the battery exchange? Looking at the pictures, it's hard to imagine... Do you had to "bolt" the battery plate with the battery's attached?



Kind regards,
Aldert

[worldofmaya]

Originally Posted by jhheli

I see less wires and no fans, are you running now just esc and bec with no fans or no additional lipos?

Maybe another way of viewing at it... that's a machine around 3000 Euros or more and you don't wanna have the safety in case of a BEC / main pack or what ever failure that you can auto-rotate your machine? Even if you never need it?
With all respect to Dave and the Mikado guys, that's a no-go for me...

[ame]http://www.youtube.com/watch?v=CVyZxjyvZxs[/ame]

Here's a little video which shows what happens... a German posted that video after the VBar meeting with the note that they said they use 4mm connectors which un-soldered itself.
-Klaus

[dahld]

@ Aaalie,

First pic is of the battery plate and a set of batteries mounted on a plate.

Second pic is of the plate mounted in the frames. The plate is secured into the frames by four 3mm bolts (one on each corner of the plate), which are only required to be loosened a turn or two each, and the plate become un-captured and can be removed/mounted, and the bolts remain with the frames. Quick and easy (-:

Third pic is a side view of the plate mounted in the frames. As you can see, there is lots of room for different sizes/dimensions of packs, and CG adjustments.

(-: Dave

[Nko15]

Cant they replace those bolts by thumbscrews?? will be alot nicer...

sorry to say, but having to loosen bolts in order to change the battery is just a cheap solution....

[ola.c]

Originally Posted by Nko15

Cant they replace those bolts by thumbscrews?? will be alot nicer...

sorry to say, but having to loosen bolts in order to change the battery is just a cheap solution....

Why not just a lock pin securing the plate lengthwise.

[dahld]

@ lunohod,

The WR BEC is set @ the 8.4V setting. Kyle's not sponsored by JR. But the fact is, in all the thousands and thousands of flights Kyle's put on all his Mikado helis over the past four years (all using JR8717's and 8900G's), we've only had one servo motor on an 8717 fail on us, and it had over 1200 flights on it.

The 8717 HV's on Kyle's three XXtremes have given 100% performance during all of 2011, digesting the 8.4Volts. One machine has about 500 flights on it, and the other two have over 300 each.

(-: Dave

[dahld]

@ Nko15,

The concept idea of a thumbscrew is good, but...

The holes in the mounting plate are actually channels running fore and aft, with a wider diameter hole at one end. So once the screw is lose, you can slide the plate to the rear and align the bolt head with the wider diameter hole, and the plate can be slipped over the bolt head (which stays with the frames).

Thumbscrews need to be a larger diameter for the human thumb to feel comfortable turning, tightening and loosening. So the holes in the plate would have to very large (too large), to slip over the larger diameter thumbscrews.

The other option is to remove the thumbscrews (four of them) each time...but what a pain. I'd lose one on the bench after the first flight (-:

I'm sure there are a variety of ways to mount the plate. But the current system is light weight, cheap to produce, easy to use, and holds the heavy packs in the frames like glue.

(-: Dave

[Inverse]

Originally Posted by 4cyclic

this heli is so beefy, bet Mikado had in mind bigger than 800's blades in future...

Hence "Xxtreme" and not "800".

[trickybit]

Ah, now I can see it... the holes are kind of keyhole shaped; you fit them over, slide the whole thing forward a very short distance, then lock into place with a quick turn on the hex bolt.

That does sound a bit better than my 3 velcro straps, but still a bit odd. It would seem that any mechanism which kept the plate from sliding backwards would work fine.

I guess the PITA factor would depend on how easy it is to get a hex driver in there to snug them up.

Definitely elegant in its way, but there's probably an upgrade out there waiting to be invented...

Cheers and thanks again for more detail and explanation.

[GB ian]

Dave, Is there any chance you could adopt me? My Trex600 stretch with the old aluminium frames is looking a bit sad compared to this! I even do my own washing!

[RRRappy50]

Daaaave!!
More pics for us?

Many thanks,best regards!

[dahld]

OK. Here's a few of the tail and head.

The tail gears are really large in diameter and mod 1.0, same as the main gear. Note the Mikado production molded pitch slider, yoke, and tail blade grips.

The tail hub is dampened, with three small o-rings per side, with a spindle shaft etc. It's like a mini head.

The shot of the main head shows the Mikado production swash plate driver arms, and molded links. The swash plate is massive, and as tight after a season of flying, as it was when we got it. Main shaft is 14mm hollow, spindle shaft is 12mm hollow.

(-: Dave

[gravydrive]

Those tail rotor grips are sexy! Mikado should use them for the T-Rex 450 VBar head!