Vortexgen

The Conversion Kit.

The kit contains the following?E

Longer Tail Pipe (anodized blue)
Longer Tail belt
Solid engine mounts (anodized blue)
Clutch shaft to suit 46-50 engine.

You will then need?E

46-50 size engine (glow plug and gasket)
46-50 size muffler, silencer, or tuned pipe
600mm Main Rotor Blades.


Let me begin by saying the caliber 30 was not designed with the thought of possibly installing a 50 size engine, so the stress, heat, power and performance factors of a 50 were not considered. As such, I would be concerned with simply slapping in a 50 on a standard caliber 30 to see how it goes.

The nature of the mod and upgrade would really only benefit people that can outfly their caliber 30 as it is. If you don?t understand this statement, you?re probably not ready just yet.

As an idea, my caliber 30 has the following upgrades already (from using the TT39) which make it more capable of handling the bigger engine. Im not trying to impress anyone but are trying to raise the point that you should have your caliber ready to handle the extra grunt with at least a few upgrades. Particularly the linkage system.

2.3mm linkages all round (not the standard kyosho ones)
QUICK UK Blade grips (metal 12mm blade grip, standard is 14mm)
QUICK UK cooling fan (metal)
QUICK UK mixing arms (metal)
Kyosho HG Swashplate (High grade ?Emetal)
Kyosho HG Aileron and elevator mixing levers (metal)
Kyosho HG Servo tray brace (prevents servo tray from flexing)
Kyosho HG Clutch Bell (metal)
Wide Skids
FT Canopy.

I also use a Governor GV1, with GY-401 on the calber.

Installation?E

Its relatively straight forward with a few exceptions.
The tail boom is easy and just replaces the original. The tail servo would then be mounted further aft on the tail boom, however, in my case, I ordered a longer tail control rod and kept the tail servo close to the frame. The boom is about 5 cm longer.

The blades are straight forward.

The engine is a bit tricky. The clutch shaft comes with 2 small screws that will be used to hold the fan on. They are very short. This became apparent because a 50 engine has a longer crankshaft, which when you screw the clutch shaft to, will protrude up into the area where the fan screws go. This means that the original fan screws cannot be used, and very short ones (supplied) have to be installed. Knowing the previous problems with fan screws coming loose, I decided to grind about 3mm off the 50 crankshaft and use longer screws. The end of the engine crank no longer interfered with the fan screws. (see pic below)

The glow plug has to be removed to get the engine installed ?Eit fouls on the forward skid as the engine is lifted into place.

The Left sideframe needs about 3mm shaved from it because the engine exhaust port is too close, and depending on the exhaust system will touch and melt the sideframe. (see pic below)

I used a Hatori silencer, and it was touching the fuel tank, so I had to make some aluminium spacers to push the pipe outboard further. The spacers were installed as if gaskets. Once again, it will depend on the exhaust system you choose, no doubt a tuned pipe and header combo would not suffer this problem.

EDIT 29th August - I now use a header and tuned pipe, no problems with spacing the silencer anymore. Be careful what you order, as hobby shops dont have headers specifically for a caliber 30 with a 50 engine, you may need further mods. -EDIT

Then it?s the usual engine and throttle linkage setup, and you?re ready to fly.

Flight?E

It has instant grunt! There is no question that the 50 engine in a caliber 30 is far more powerful than standard. The bigger blades make it more responsive, faster, and the 50 certainly keeps the power to the blades without problems.
The tail response is surprisingly even better (the caliber M50 has the same tail rotor diameter and gear ratio), I had to adjust my gyro gain up a bit, and piro rates were wild. Inverted acceleration, tick tocks and flips can be performed almost endlessly with good collective and cyclic management before noticing any power drop. Climbout is impressive, to say the least.
Autorotation is incredibly forgiving, in fact I oversped the rotor a number of times. You can auto and take off to about 2.5 feet then land again before the inertia is gone.

Downside?E

I used to get 11 min flight times with the TT39, now I get about 8.5 mins. I?m using the OS50Sx-H. (flight times calculated with the GV1 on and maintaining constant rpm from start to finish, obviously practicing autos or a normal throttle curve will extend the flight times)
The engine, engine mounts, sideframes, and everything nearby get very HOT which concerns me. I have added more cooling holes in the FT canopy (standard canopy is probably ok with its massive inlet), richened the mixture up, and added a spoiler to catch the forward air and direct it to the engine head. Still I?m experiencing high engine temps. I use 23% nitro, but may switch to 30% for more cooling. I now fly the 8-9 minutes then let it cool for about 5 before flying again.

EDIT 29th August - Cooling is no longer an issue, probably just new tight engine getting hot in its limited space. Now after 5 or so gallons, I dont think its a major concern, but would still check the temp periodically. I have gone to 30%, but the last gallon of 23% was not getting the engine that hot anyway, Ill go back to 23% after this 4 gallon drum of 30% as its cheaper. EDIT

The mechanics so far ( after 1.5 gallons) seem to handle the added power and stress ok.
I did destroy a clutch liner with the added power, from doing a power recovery (after auto). The power recovery was necessary because I was running on and the heli just didn?t want to come down out of ground affect! It drifted off the end of the flight area so I powered out. I believe the instant feeding in power destroyed the clutch liner. The liner was however, very worn, and may have only lasted a few more flight with the TT39 anyway.

I will continue to monitor the clutch liner, and see how my one way bearing handles the power. (its still original)

In conclusion, I don?t want to go back to the TT39, and if the caliber continues to withstand the added power, I can?t see a need to.
It?s definitely more powerful, more responsive, more forgiving, and yet more stable, and still a cheap platform to practice, practice, practice without the worry or high expense of destroying a 60-90 size machine. (been there-done that!)


here are the photos, starting with the simple kit. It retails for 9000 Yen, which is currently about $75 US.

Vortexgen

My cal30, showing blade grips, swashplate and linkages all upgraded as well as the servo tray brace etc...

Vortexgen

the parts kit. approx $75 US.

anodized blue tail pipe and engine mounts. (slighlty darker than the quick products), tail belt and clutch shaft

Vortexgen

The engine mounts, old and new.
The 50 size has lower engine mounting holes and is actually a solid piece, making it retain the heat produced from the engine by not acting like a heatsink.

Vortexgen

the tt39 on the left and OS50 on the right. Notice the length of the crankshaft is considerably longer on the 50.

Vortexgen

The first problem.

because the crankchaft is longer on the 50, it extends up into the clutch shaft and prevents the fan screws from being installed.

the clutch shaft does come with 2 very short screws but they would only be gripping a very few turns into the clutch shaft. These have been known to come loose on the 30, so I grinded about 3 mm off the crankshaft and used longer (original) screws to hold the fan more securely.

Vortexgen

the second problem.

The engine is larger and the exhaust port is further forward which makes any header or muffler base foul on the sideframe. I had to shave about 3mm off the sideframe to accomodate the exhaust. This photo before the trimming to show how close the exhaust and frame is...

Vortexgen

well thats it, sorry no flying photos.

here is one of the benefits of having bigger blades and tail pipe though.......

wouter

wow!
now that's nice man.
Thanks for doing the review.

Hope we will be able to order it somewhere and soon!

davidj

Proof there is life after 32 (or 39)

DSA.308

My Feedback: (6)

Nice job, you ever thought of a career as a journalist for a R/C magazine? And the conversion is nice, sounds like the 30 is gone from that bird for good, so long as the longevity remains huh?

Vortexgen

i'm really throwing the caliber around now that it has the 50 to see what breaks.

with the larger blades and hence rotor area, its cyclic response has increased to the point where i have had to set dual rates to 85% for the same response as before the upgrade. keep in mind, nothing has changed in the servos or linkages, only that it has bigger (600mm) blades on it. My dual rate with the 550mm blades and TT39 were set at 115% !!!

strangely, with a full power vertical climb (from sitting on the ground with the gov on and regulated to 1700) the gyro can not hold the tail even in HH mode if its gain is low. i increased its gain slightly and it suffers no more anti torque problems.
strange, cause its in HH, and has good tail authority/tail rpm.

another thing to tame the beast, i had to drop the gov idle up2 (3d) speed from 1850 (550 blades) to 1700 (600 blades). Its just way too responsive spinning the 600mm blades at 1850!!! my current setting on 1700 is good, my tuned pipe is just on song, and its performing everything i ask without hesitation.

what a beast - getting some inquisitive looks from the 60 guys too!!! (they're threatened by whats under that cowl, LOL)

WillMac795

Looking forward to seeing what the long term outcome is, maybe I'll get one some day if I ever outfly the 30

Tongie

Vortexgen, many thanks for putting in the effort to share your 50 conversion kit experiences.

Don't know about anyone else but I know I am convinced and in fact have a conversion kit on its way from Japan as of tomorrow.

I am going for the same set up with an OS 50 but will be going for the Hatori tuned pipe instead of muffler(540+541), you seem to prefer the mufflers but everyone who I fly with use governors with tuned pipes and fully recommend that combo. What are your negative experiences of tuned pipes and Governors?

WillMac795

Hi Tongie, how much is is costing you to get the kit over here?

Cheers

Tongie

£65 including postage and taxes for the kit which is as Vortexgen purchased, (engine mounts, boom, belt, clutch shaft).

WillMac795

That's not bad really. Are you using metal blade grips etc as well?

Tongie

Yes, I have the new Quick UK silver blade grips, mixer arms, swashplate and cooling fan. I share Vortexgen's concerns over the strength of some of the stock parts so would recommend these upgrades before considering a 50 conversion.

Vortexgen

hi tongie,
I have been using silencers only here in Japan because of the noise. I fly in a farmers paddock, on the bank of a river, and on the other side of the river are a few houses. We dont want to receive any complaints so try not to fly too close to the houses and try and keep the noise down.

Anyway, I had a few teething problems with the 50 size silencer (probably because i had to space it out to clear the fuel tank) and have subsequently bought the Hatori Tuned Pipe and header.

I dont think its any louder, or not much louder, than the silencer.

The header I bought swings forward and up and interferes with the forward canopy mounting standoff. I just moved it up a bit to fix this. (I think it was an ERGO 50 header, obviously there is no caliber 30,50 size header yet)

Anyway, the pipe is "on song" with the governor, and the heli is still going great. Just ordered another 4 gallon 30% Nitro mix as Ive already put my previous 4 Gallon drum through it. This equates to approx 48 flights at 9 minute average, or 7 hours and 12 minutes of flying with the 50 setup.

The one way bearing, clutch, gears, and everything else are still holding up well.

Make sure you order blades that fit the 12mm QUK blade grips.
I also upgraded all the links to 2.3mm, especially the 3 long standard ones from the servos to the elevator/aileron levers bend easy. (these bent on mine even with a TT39)

Im so used to the 50 now, i have forgotton how large the difference between the 50 and 30 is. Maybe ill fly one of my collegues 30s this weekend to refresh my memory, and maybe offer more insight.

JunkMan304

My Feedback: (3)

Thank you very much for the review.

Tongie

Vortexgen,

What head speeds are you using on your Governor now and did you need to change your pitch ranges on the main blades?

Cheers

Vortexgen

hi tongie,
the whole machine is much more radical and needs to be tamed down a bit given its extra power and rotor area.

I didnt change the pitch curves at all, but noticed during autos i dont need anywhere near as much negative pitch. It overspeeds pretty easy, making autos easy, i just dont need to bottom the collective transmitter stick now, but still have -4deg if needed (now doing high speed low level flybys, then switch to HOLD, pull up, stall turn and auto)

Top and bottom pitch is still around +10 and -10 degrees.

I did change (lower) the dual rates to tame cyclic response and increased gyro gain to get the tail behaving better.

The heli is very quick and responsive. ( i was at 115% on elev and ailer dual rates, now had to go to 85%, and its still more agile than it was with the TT39)

I also now run the headspeed at only 1700 for 3D. seems more than enough, its like a bat out of hell upright or inverted and everywhere inbetween.

Mainly i reduced it for fuel economy, but at max collective the thing is gone.... (strangely, it is more economical at 1700 (IDLE 1)than at 1550 (NORM)- maybe tuned pipe effect)

Keep in mind, I threw a clutch liner very early with the OS50. it was already very worn anyway so its a bit inconclusive if this is a potential problem.

Currently, if i give it full stick from the ground, i can see that the torque is really fighting the tail rotor. I have had the tail let go once or twice over many hours, and are still investigating why this can happen. maybe clutch slipping, or gyro problem or something. (its not tail authority, because i can hold it straight with a little opposite rudder, just seems that heading hold cant keep it there. this has happened only a few times and not really a concern)

Caution doing power recoveries, the instant power was what took my clutch liner (old worn one) out last time. Im going to keep a spare clutch bell in my field box.

Its got grunt.. and tons of it!!

Tongie

Should receive my conversion kit any day now, can't wait. Thanks for your help on this.

Cheers

optech

My Feedback: (9)

Hey Tongie....

Hook us up on how and where you got the Kit!


Mike

Tongie

Hi Mike

From www.rc-champ.co.jp the site is in japanese but they respond in English to emails. It cost :

Upgrade kit 5880 YEN
Spare boom 630YEN
Spare belt 980YEN
Hatori 540 pipe 4875YEN
Hatori header 2400YEN
Postage, tax and paypal fee = 4331YEN

It arrived in 3 days but I had to pay UK VAT and duty totalling £30GBP as it was sent using speedpost, will know to use air freight next time!

Cheers

Ian