gaui 200 md500 help..5 blade suggestions

[Incarus]

http://www.empirerc.com/hurricane-20...it-p-4828.html

got the above kit from a member here..

1st..wanted to know if there is a 5 blade rotor other than guai"s that people have used succesfully...the oem 5 head is expensive

2nd...any suggestion..is this a PITA etc

thx

[BHChieftain]

Here you go! Nexgen did a build thread on it:

https://www.helifreak.com/showthread...ighlight=md500

I almost tried this, but I crash my gaui a little too often to want to put it into a scale body...

Chief

[Incarus]

thx!!!

[alphonso]

I have the MD500 kit with 5 blade head and there is a serious issue here. The primary tail belt has a lifetime measured in minutes and no one has had any in stock for a year and Gaui have discontinued the supply of any parts for this heli. I bought many spares for the gaui 200 and the MD500 but could find no spare belts. I even bought another body kit to get a belt and that lasted half a flight. I suspect its to do with the age of the stock. Even flown as a 2 blade Gaui 200, all stock except for the the raised boom and belts, my last belts lasted 2 flights.

I was really dissapointed as it looks fantastic. There is the possibility of getting belts made up from a specialist supplier. i found one in UK that sounded confident they could get any belt down to 3mm wide and no less than 50mm in circumference.

[alphonso]

the UK firm I contacted about belts was HPCgears.com . I spoke to them on the phone and they sounded confident they could supply the belts, even the small primary drive belt as it has a circumference greater than 50mm.
when I eventually get round to sending them my old worn belts for measuring I will ask about stronger materials such as those used for the X2 belts.

Allan

[DMala]

Originally Posted by alphonso

I have the MD500 kit with 5 blade head and there is a serious issue here. The primary tail belt has a lifetime measured in minutes and no one has had any in stock for a year and Gaui have discontinued the supply of any parts for this heli. I bought many spares for the gaui 200 and the MD500 but could find no spare belts. (...).

My EP200s were bought used, and each came with a lot of spare parts. I found two belts for scale model, part 861903, NIP. If you PM your address I will be happy to put them in a letter envelope and mail them to you for free.

Are you sure that there is nothing wrong with your setup? Such a short belt life looks suspicious.

[alphonso]

thankyou so much, your timing is impecceable. I just ordered a new V2 frame and some DS09's to build it again. I will find the optimum set up for 5 blades before I fit the raised boom and belts this time.

I'm going with 5600KV motor with 10 tooth pinion. I looked everywher for a z power 5150 with no joy.

I also used a V throttle curve before whilst testing so this time I'll use a flat curve about 65%, or finally fit the CC25 with governor I've had laying around for ages. This again , will be easier on the problem primary belt.

I bought 17 and 18 tooth pulleys for the integrated middle mount to raise the tail speed to counter the lower headspeed and will use the 42mm tail blades.
I wish Spin made assymetric blades in 205mm as torque would be less and flights would be longer, I may still try and make some ( I remember when most EP helis came with assymetrics as std, 90% of flyers never even attempt any aerobatics so the markets there )

I will post up a little log if I'm succesfull as one or two people have asked about this kit.
Nexgen's build is nice for the body alone but offers no help for the 5 blade head.
To be honest , I assumed the reason very little is mentioned online about the MD500 AND 5 blade head is because its a bit of a pig to get right.

Thanks again mate, just about to pm you. If I can ever help you with a hard to find spare just ask as I've aquired a rather large collection.

Man is well chuffed, Allan

[BHChieftain]

Hi,
Do you need lower headspeed with a 5blade rotor vs. 2?
Chief

[alphonso]

Do you need lower headspeed? Theoretically no, but considering the headspeed of the stock heli I would think thats a lot of wasted energy. Plus I want as long a flight time as possible, I got 6 mins using 2S 1300 Hyperions and want to keep vibes to a min so lower headspeed will help there.

To keep tail power up I have 18 tooth primary ( stock is 16 ) and will use 16 tooth tail pulley and Gaui say you should use the 42 mm tail blades with the 5 blade head and scale body.

I wanted to use the Bobby Watts tail as its so smooth but the MD500 tail fin doesn't fit very securely to it as it only has 2 fixings on the left hand side, compared to the stock V2's 3 screws. Vibes do transfer to the tail fin so i want it more secure. I've ordered a 255 16 tooth tail pulley and BW tail hub to fit to the V2 tail as it feels better balanced with its grub screw opposed to the nut and threaded shaft.

I also have a Hyperion / Scorpion 2206 5300KV coming to try in it. I was going to take the 5600KV out of my 3 blade EP 100 but I couldnt do it. ALLeRC have them for $19 at the mo which is roughly half price.

[BHChieftain]

I think the lower headspeed is a good idea...
Chief

[milliotseb]

If the belt manufacture could be done, keep us updated as I would also be interested to build one. I will use the 2 or 3 blades FES head.

I still have a MD500 scale kit NIB but not much spares for it. Too bad Gaui stopped the 200 support but I also have to agree that there is a lot of 250 fuselage on the market.the GAUI complete scale model with 5 blades rotorhead was so nice looking

[alphonso]

I have 4 sets of the MD500 belt sets now. I shall try one of those first before I get prices for manufacture. I was planning on getting quite a few made if the price was right. That way I can help others out hopefully.

I've built the donor heli, fitted the 5 blade head and have had about 15 test flights to get the set up right for duration.
The Castle Link hasnt arrived yet so I have no idea what the headspeed is as I can only measure 2 to 4 blades.

However my setup is as follows.

Hyperion 2206 / 5300 ,10 tooth pinion
- 3 to 9.5 degrees pitch travel ( swashmix at 26 % )
Flat 55 % throttle

I wanted very gentle collective to save the primary belt with just enough power for safety when turning downwind. It feels about right here and also yielded the longest flight time with 600 mah of a G3 CX850 used in 4.30 mins.
Cyclic response is obviously still quite awesome due to the extra authority that 5 blades give.
I have a tiny amount of tail lag ( very tiny ) which will go when I fit the new Integrated Middle Mount as I can change the primary tail belt pulley to a larger 17 or 18 tooth.

So its ready to have the raised boom fitted and basically see how long one of the new primary belts lasts. If I'm totally honest, I'm not very confident as this is the third attempt. Although I didn't use such a gentle throttle before and probably put too much strain on it whilst holding it down and tracking the blades, at least that's what I'm telling myself.

I had another idea if I have to have some made, I could have the belts made a little longer and could use a couple of idler gears to increase the belt and pulley contact area, this would likely reduce wear.

Take care, Allan

[alphonso]

Last night I fitted the raised boom and spun it up to 50% stick and all felt smooth. However the primary belt has a little thread hanging from it already, this after 30 secs at half throttle and 3 degrees pitch, doesn't bode well methinks.

I have fitted the fuselage and will maiden it today with a hyperion EX 1100 2S, fly for 4 mins and then pull it apart and check the belt. If it shows sign of increased wear there is one thing i can try. I noticed that the primary belt is not perfectly parallel to the main gear, it is almost touching the main teeth and so may actually be touching when spun up. Even though I spotted this I elected to sacrifice one precious belt, observe its possible demise, make an alteration by turning down the outside flange of the integrated middle mount pulley, so raising the belt and then trying again.

I will get there, Allan

[BHChieftain]

Got any pics?
Chief

[alphonso]

I keep meaning to snap some pics, but then the light fades when I've got it back together after altering something,
I also dont want to jump the gun before it is reliably flying and I really have something to show off.
I got 3 very nice flights out of the belt before it suddenly failed. I was expecting it, so was over carpet just out of ground effect. It gently settled on its skids as I hit TH, the 5 blade head will actually auto, which is nice.

My first flight earlier was fine, after taking off for a second flight, the primary started slipping on the 16 tooth lower pulley but looked undamaged so I drilled a 1.6 mm hole in the integrated middle mount and tapped it for M2. I then took a EP200 belt guide and spacer and added a little tension to the slipping belt. This gave me the 2 extra perfect flights of 6mins duration.

Without thinking I fitted the tensioner wheel to the side of the belt which is under tension, this is not correct. You can see a correct example in a heli tail pulley. So I shall mount the wheel on the other side with a little less tension. It will also be a belt that is new and has not suffered any slipping.
If this doesnt work with belt #2 I have an idea to modify a 15 tooth X2 tail pulley to use in the Middle Mount pullys' position. This will make the belt slightly looser and allow me to wrap it round the pulley more without adding tension to the nelt. That's how the X2 tail pulley works so it;s worth a shot.

I'm working away this week so it will have to wait until next weekend

[BubbaFett]

Hi Alphonso,

I'm putting together a MD500, 5 blade head, at the moment too. The belt issue has got me a bit nervous as I don't have a spare and can't find any on the web. Did you have any luck with an alternative supplier?

[domcars0]

Originally Posted by BubbaFett

Hi Alphonso,

I'm putting together a MD500, 5 blade head, at the moment too. The belt issue has got me a bit nervous as I don't have a spare and can't find any on the web. Did you have any luck with an alternative supplier?

I'm also interested to find those MD500 belts!

[Kevinfly]

Any updates?

[Tilting At Windmills]

I too fell in love with the look of the MD500 but was also been grounded quickly by the fragile tail belts. Currently I’m in the middle of testing a possible solution by eliminating the dual belts and going with a direct-drive raised tail using the stock Hurricane 200 tail belt. Surprisingly with some careful removal of material there is just enough room to fit the center tail gear in the upper frame (at servo level) for a straight line to the raised tail. A custom tail-belt guide-wheel mount and a 3-cell power upgrade completes the primary modifications.

Here is a photo of the middle-mount modification for the tail-belt guide wheels – I was experimenting with wheel placement which is why there are 4 holes drilled in the brass plate.


Here is the current flight platform with the 2 blade head:

-link to a larger version of the photo above: https://farm8.staticflickr.com/7102/...0d708af1_o.jpg - viewing at 100% you can see the 2 red tail drive gears tucked in below the upper main-shaft mount.

This week I’m tuning the flight characteristics before risking the MD500 body but have put 5 packs through the bird without issue. Provided I can get a dozen more packs through the airframe in the next week or so, the upgrade path is to add the 5-blade head, get that tuned, then put the scale body back on.

I’ll let you all know how it goes.

[DMala]

Interesting, thanks