Blade SR Belt Drive Tail Upgrade

admiral · Posted: Mon Jun 13, 2011 4:40 am Post subject: Blade SR Belt Drive Tail Upgrade

After 12 months of not being happy with my purchase of the Blade SR I decided to do something about it, a tail upgrade from Freestyle Hobbies in Adelaide to get rid of Thombo’s pet hate that pesky tail motor and replace it with a belt drive tail.

SR with Tail Motor

To give it, it due the SR does fly, but it doesn’t live up to all of the hype about being the next step up from the Co-axial an being rock stable and easy to fly, to the stage that a long time ago I put it back on the shelf and moved up to 450 & 500 size both of which are far more stable & predictable than the SR now it’s time to go back and see if I can tame the twitchy little beast that I find hard work to fly.

Upgrade Kit

The upgrade kit contains everything you need to do the conversion plus I purchase the hardened aluminium tail boom (predrilled) and the Gauge/drill set, along with these there is also a crash kit which has extra plastic part that may get broken in a hard landing, and the instructions. The instructions are the only complaint that I have of the whole kit, they provided all the information that you need very clearly when you read them with a magnifying glass, dam that print is small.

The first step was to remove the tail assembly the head and main gear, assemble and fit the idler pullies which are held it with two screws through the frame, this is the only frame modification, then attach the belt drive gear to the Main gear which is done using clamps with no modification to the main gear. That’s the frame finished then it was only a matter of assembling the tail and fitting the tail servo which is not supplied, for a tail servo I used an Eflite S75 which had been removed from the B400 when I upgraded to HiTec 65MGs. To this point the upgrade had taken an hour and if I had been using a standard main gear would have been finished, however I have a Microheli Main gear fitted with a slightly longer centre boss which was preventing the belt from running true, whip the main gear back out trim 1mm off it with the Dremmel tidy up any burrs and refit it another 10~15 minutes and job finished.

Finishd SR with Belt Drive Tail

First flights in a confined area were very encouraging, still had the pronounced drift to the left if you let it, but a tad quicker on the throttle and up she goes, gone is that pesky buz buz buz of the tail motor and it feels far more controllable, at that point poor workmanship on my part steps in, the ball on the tail server arm lets go, rapid swing to left taking out a pot plant the Jesus bolt, one blade, the feathering shaft and the main head.

Overnight rebuild and we are ready to go again, back to hovering OK in the rumpus room and on the Patio not game to do too much the missus likes her pot plants and I still want to eat around here, looking forward to some fine weather to give it a proper flight, but at this stage I would say that this exercise has proved Thombo’s first law of Model Aviation, tail motors are crap on anything bigger than an MSR.

My conclusion is that Freestyle Hobbies has done what Horizon should have done in the first place created a great little belt drive tail CCPM helicopter and they carry all the spares to support it, well done Freestyle.
http://www.freestyle-hobby.com/

nick_onelove · Posted: Mon Jun 13, 2011 6:42 am Post subject:

Haha, not a pot plant! I learned early on not to fly near the "crops." Laughing

I've heard that direct drive tails are bad on bigger helis, the SR and CP Pro are basically the only Blades I didn't get because of that. Oddly enough though, I've found that 120 SR tail actually holds better than the mSR.

Kind of off topic, but I saw a thread somewhere where someone modded a variable-pitch direct drive that looked pretty promising.

Anyway, good luck with your next flights; it certainly looks well done, it looks like it came that way.

metalwizard · Posted: Mon Aug 06, 2012 1:41 am Post subject:

Admiral. I talked with you a bit on the other thread (double horse 9116) about upgrading to a blade. you said to stay away form the SR

Well I have found that my local shitty hooby shop carries some stuff from Blade. and that might be my deciding factor on what to by I'd hate to not have any local help/ parts available.

so If I decide to go with the SR and purchase this upgrage do you think I would have a decent enough heli to enjoy??

I have also seen carbon fiber and plastic blades available for this AND full on aluminum head parts.

I would feel better buying the blade over say a t-rex again because at lease with the blade I do have some local help and parts.

bottom line with the belt upgrade is the SR at least a decent bird??

Thanks

admiral · Posted: Mon Aug 06, 2012 3:45 am Post subject:

Hi Metalwizard,

The belt drive tail did improve it, took some of the twitchyness out of it and got rid of the annoying Buzz Buzz of the motor, but still never really flew right, I got rid of it and built a Trex 250 clone it flys great and came in at about half the cost of the SR.

http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=25146

Only problem I've had with it are the crappy screws they supply.

metalwizard · Posted: Mon Aug 06, 2012 4:04 am Post subject:

Thanks Admiral.

tombo242 · Posted: Mon Aug 06, 2012 4:13 pm Post subject:

That's a really good mod Keith and very well done. One tail motor down and thousands to go. Good that you saw an immediate improvement, I feel vindicated in my pet hate. Razz

Tom.

metalwizard · Posted: Thu Sep 13, 2012 1:02 am Post subject:

Well I broke down and did it.. I LOVE this mod.. no more Buzz smooth etc.

BUT I am having a tail wag problem.. did you run into that. got the yellow wire plugged into 5 got the knob at 12:15 and its still waggin.

any thoughts or suggestions??

admiral · Posted: Thu Sep 13, 2012 6:08 pm Post subject:

Hi Metalwizard,

Didn't have the problem on the SR but did later on a Trex 250 I replaced the SR with, the Tail servo was too slow so I replaced it with a DS420 Align tail servo which was about twice the speed and that fixed the Tail wag.

metalwizard · Posted: Sun Sep 30, 2012 5:58 am Post subject:

So I have had mine on for a couple weeks a little touchy but when its working its great. Till today one of the pully screws came loose and I chewed up the belt..

So I have found that the WASP V3 or V4 (not sure which) tail is what the freestyl kit uses.. so I can order replacement parts CHEAP in the US No 3 week wait EXCEPT for the dang belt... the Wasp one is way to short..

Any ideas on where else to get a belt?? I cant seem to flind sizes anywhere..

admiral · Posted: Thu Oct 04, 2012 4:22 am Post subject:

Only supplier I know is the guy in Adelaide Australia, but if you can find the number of teeth and the section on the belt they should be also used for other things and available from other sources.

hnoor0055 · Charging Joined: 26 Mar 2016 Posts: 1

Till today one of the pully screws came loose and I chewed up the belt..