View Full Version : SNHobbies Flasher 450 V2 Build/Review ($135 Metal Heli)

04-08-2009, 05:44 PM
This is a build/review thread for the $135 SNHobbies Flasher 450 SE V2 found here: SNHobbies Flasher 450 SE (http://www.snhobbies.com/product_info.php?cPath=22_38&products_id=461)

I saw the price on this kit and I just couldn't pass it up. Shipping was prompt and the heli made it's way to me in about 7 days from Canada. I purchased the kit with the ESC and Motor. The kit comes with a 13 tooth pinion which the manual recommends for 3D flight.

The kit is marketed as a 100% T-Rex SE V2 parts compatible. After tearing it down and looking it over real well I'd have to say this is an accurate statement. The only part I've seen that's noticeably different from the align kit is the head button.

Flasher 450SE Unboxing Video

04-08-2009, 05:48 PM
The Flasher 450 comes about 70 percent assembled. All of the major components are complete including the tail, head, and main frames.

So the first thing I did was to tear down the main frame and look for anything out of place. The main frame is said to be made of carbon synthetic fiber but I do not know enough about frame materials to know if this is accurate. I can tell you that the frames are very strong and made of some type of weaved material.

Taking out the first screw I immediately noticed that there was very little thread lock anywhere on the lower frame screws and I would need to go thru all the screws on the frame and make sure they were all secure.

The bottom plate was also not fitting well with the bottom frame and I had to sand the frame halves a bit and clean up some flashing on the plate to get it all to sit flush without the frame warping a small amount.

04-08-2009, 05:51 PM
So once the frame was back together and everything was thread locked I decided to tackle the tail.

Make sure to check this assembly over for threadlock. The tail blade holders had a small amount of thread lock on them but they were quite loose. I also found that the pitch control arms required a little sanding to be free enough for my liking.

Other than that the tail looks to be in excellent shape and is nice and smooth. Overall quality and finish is very nice.

04-08-2009, 05:53 PM
The kit comes with a Carbon Fiber tail boom. Installation was trivial. I used a string to pull the belt thru the boom and then installed the belt on the belt pulley. I then did the rest of the tail installation with the two fins, boom braces and servo mounts. This part went without issue.

I also installed the skids at this point as well.

04-08-2009, 06:03 PM
So next I decided to tackle the head. So far the kit looks identical to a Trex SE V2 and I must say the material quality is about as good as I've seen with align stuff.

Again, make sure to go over this part of the heli with threadlock.

1. I also noticed that one of the blade grip screws came off with only a few turns of the screw driver. So I pulled the grips and I found that I could not tighten down the grips without them binding. So I pulled all of the bearings out of the grips and went over them really well. That's when I found that one grip had the following setup:

bearing -> bearing -> bearing -> washer -> thrust bearing -> washer

It's supposed to be:

bearing -> bearing -> washer -> thrust bearing -> washer

I found an extra bearing in one of the main blade grips. Once that was removed the main grips went on without issue. So I've now got an extra bearing :)

2. I went through and also made sure all of the links were sized using a ball link sizer. This fixed a little of the stiffness that I had in the head.

3. The head was still a little stiff for my liking so I rechecked the washout and pitch control arms. In both cases I found that the reason for the binding was missing washers. There should be

washer - bearing - bearing - washer - screw

for proper mounting. If you are missing either of the washers you will bind the outer bearing when you tighten it down and that's what is happening in this case. I switched from blue loctite to red loctite so that I could only tighten the screws down to where there was the least amount of binding that I could without causing a lot of play in the head. I will need to get 4 washers to fix this in the future.

4. In the main grip assembly the o-rings used are V1 Trex style. They are meant for the 3mm spindle shaft. While you can use them, getting the spindle thru them while keeping the o-rings in the center hub is extremely difficult and I was unable to do it. I switched them out for some Trex V2 o-rings that are meant for the larger 4mm spindle.

5. Note: that inside the bag that had the head assembly there are 2 tiny washers. They do not show in the manual where these go but these are spacers that are used between the flybar cage and the flybar rocker. They are needed. I've included a picture to show them

04-08-2009, 06:07 PM
Not a lot to do here. First you install the main gear into place and then slide the pre-assembled head and main shaft thru the guide bearings. Lock the main gear with the set bolt and then tighten down the upper collar and you're done. Nothing complex here. :ws:

One thing to note is that the screws for the anti-rotation bracket were nowhere to be found in my kit. I just grabbed some screws from my parts bin but that is something to note. It would have been nice if there was a spare parts bag included with the heli.

I did find the only part that's not 100% identical to a trex. The head button is taller and smaller.

04-08-2009, 06:15 PM
Chosen Components:

Cyclic Servos: HS-65
Tail Servo: Hyperion DS12-GCP Digital tail servo
Gyro: G401B
Receiver: Spectrum AR6100
ESC: Jeti Spin 33
Motor: 500XH (3300kv) motor on the 13 tooth pinion
Battery: Evo Lite 2100mAh 11.1v

The frame required a tiny amount of filing for the HS-65's to fit smoothly. I probably could have gotten away without filing but decided to play it safe. I used some old servo arms I had laying around and cut them up to use as spacers for the elevator servo to get the proper geometry. I used the second hole on the HS-65 horns.

The rest is just simple component placement. No real issues here

04-08-2009, 06:23 PM
After completing the build I have to say I am extremely pleased with the heli. During final inspection I did find that the included main blades were warped but SNHobbies is shipping me some new blades for replacement. That happens. My Gaui Hurricane came with badly warped blades.

Only items I have to say to be aware of when building the heli are:

1. Those missing washers on the pitch control arms and washout arms
2. The small o-rings are hard to work with. I recommend getting o-rings with the proper 4mm ID
3. warped main blades but SNHobbies is replacing them.
4. I did find that extra bearing in the blade grips. I'm sure that was a simple mistake and my kit is unique in this.
5. I definitely recommend a tear down before flight if not for just the thread lock check.

Some other items to note.
1. The flasher paddles come in at 5.8g each. My align paddles are 6.1g each. They look nearly identical and work extremely well

2. The cheap G401B gyro seems to be doing quite well. I had some drift until I upped the gain. I think I'm at about 40% now. I see no loss of hold on pitch pumps with the hyperion servo. Seems to be a nice setup so far.

3. Flasher Heli weight with No main or tail blades, no motor, no electrics. Fiberglass canopy on: 358g (12.65 ounces)
That's significantly less than the advertised weight.

I am extremely pleased with this heli. It's an amazing value at $135 shipped. SNHobbies has also been a great vendor to work with.

I give this heli a Buy recommendation.

04-08-2009, 06:24 PM
Here's some video of the maiden flight using some t-rex 325 woodies.


04-08-2009, 08:20 PM
Nice find. As I was looking through your pics, I would swear that it was a T-rex 450SE V2 other than missing the Align lettering on some stuff and the color of the canopy.

Good find! Can you give me a breakdown of what you paid for everything? I've got a couple friends that may be interested in going that avenue.

And from watching the vid, the only thing I really noticed is that it sounds like the motor is bogging down as you are going inverted. Would you agree? If this is such a deal, I may recommend some people go that way to start.

A new T-rex 450SE V2 is about $440 with motor, ESC, and battery. If you can get a better motor through SNHobbies (when I first looked at it, I thought it was SNobbies :) ), I think it would be a great deal. Was the $135 shipped with the motor and ESC?

Thanks for posting this. Good report!

04-08-2009, 08:34 PM
Hey HeliG,

SNHobbies now sells the kit with the ICE 3500kv motor and ESC for $159 shipped. I bought mine before the ICE motor was available and got some noname motor and esc. I have not tried the motor and ESC mine came with. I ended up using an old motor and esc I had on hand that came with my Dragonus.


As you could tell in the video the Dragonus motor really bogs hard so I'm going to be trying something else.

As far as cost goes...
1. I'd recommend getting their motor and esc version for $159. Great deal.
2. I'm using the $35 G401B gyro right now. Amazing gyro for the price. The only time the tail kicked was when the head speed dropped to low on that one flip. Setup was exactly the same as a GY401. Very impressed with that cheap gyro
3. I used 3 HS-65's I had laying around so those didn't cost me anything.
4. I bought the Hyperion servo from here for less than the advertised price. Best cheap digital tail servo I've found yet. http://elektrorc.com/product_info.php?cPath=77_78&products_id=731
5. I reused my radio and had an extra receiver so those didn't cost me anything.
6. I've got a few of the flightpower evo lite 2100mAh packs so those didn't cost me anything to fly this heli either.

So it basically all added up to around $220 RTF. They have a 4 pack of the towerpro servos for $19 when you buy the kit so drop the digital tail servo and use the towerpro and you're at 220 without battery and receiver. Not to bad.

04-08-2009, 08:38 PM
Oh and I almost forgot. I also purchased their Flasher 450 PE kit which is basically a Trex 450S. That will be coming with the rest of the components.

That kit is only $60 shipped and I'm putting 3 of their digital MKS S311 Digital Servos on the cyclic of that one. I'll review that kit when I get it as well. From what I can tell it looks like a Trex 450 S but with the main blade grips updated to the 4mm shaft instead of the 3mm the 450S uses.

04-18-2009, 05:11 AM
A few days ago I recieved a package from SNHobbies. It had a Flasher PE, Motor, Speed Controller, and gyro. I Thought I would post my thoughts so far on the PE kit

Overall really nice. I've only torn down the frame and looked at the components so far. Compared to other helis in this price range the things that stand out to me are:

1. Nice strong frame. It looks like G-10. Very strong and rigid
2. Lots of metal on the head. motor mount, all metal swash, center hub, washout base, flybar rocker.
3. The plastic bearing blocks and boom block all have aluminum tubes molded in for mounting. Much better than screwing into plastic.
4. blade grips are the 4mm V2 style. This is a plus and minus. While I prefer the V2 design you can't go to the LHS and get replacement grips as Align never manufactured a plastic V2. If I do ever damage the grips I'll just upgrade to the CNC ones anyway.
5. Found a lot more threadlock on the frame than I did on my SE kit.
6. Bottom base plate fit much better onto the frame sides than it did on my SE kit. Did not take modification.

Some things I noted:
1. Frame was not assembled square from the factory. Had to tear it down and square it up.
2. I had 2 stripped hex screws.
3. All ball links are backwards. A is towards the ball and not facing out. Had this on the SE kit as well. I didn't fix this on the SE kit yet as all the links are on very tightly but I may go back and fix this on both helis.
4. Many of the links will need to be sized. The head and tail are quite stiff. Not uncommon though.
5. Mine still has the short screws for the blade grips. Will have to find longer ones. I've been told the next batch of kits SNHobbies gets in will have the longer screws.

So far I'm quite happy with the kit for the price. You don't normally find this much metal and such a rigid frame on kits this price.

04-29-2009, 05:21 AM
I got to fly the SE Flasher on the ICE 3500kv motor today on a 13 tooth pinion. This is the motor SNHobbies is now shipping with the kit. I run a 90-100-90 throttle curve. Performance was amazing compared to the motor I used in the review video (dragonus motor). I was able to bog the ICE motor but I was really pushing it hard. I'd definitely say the motor is good for sport or mild 3D fliers. Amazing value for the price.

04-29-2009, 05:58 AM
Good update there LOstSOul. Thanks. I just wish I knew of someone in the market for one of these...

05-09-2009, 05:27 AM
Added a video showing what's included in the box for the heli to the first post.

05-27-2009, 01:41 AM
Oh and I almost forgot. I also purchased their Flasher 450 PE kit which is basically a Trex 450S. That will be coming with the rest of the components.

That kit is only $60 shipped and I'm putting 3 of their digital MKS S311 Digital Servos on the cyclic of that one. I'll review that kit when I get it as well. From what I can tell it looks like a Trex 450 S but with the main blade grips updated to the 4mm shaft instead of the 3mm the 450S uses.

I kind of followed the opposite course you did. I bought the 450 PE Kit first. After breaking the tail, I discovered that you cannot replace it unless you order from snhobbies. The nearest thing to the tail is the metal SE (I think V2) tail from Align. This troubled me as I didn't want to spent as much for a metal tail as I did for the model itself. So I ordered the metal Flasher, which seems to have more interchangeable parts with trex. Currently backordered so I'm just waiting....

About the Motor/ESC. Mine lasted two flights and now the motor pulses about twice a second under light load. Not sure if it is the ESC or motor but it causes the whole heli to shudder. Can't recommend this combination. Still trying to find if they have/honor a warranty.

05-27-2009, 02:11 AM
Interesting. What parts didn't work on the tail for the PE?

Which motor/esc did you get? I've found the ICE motor and MKS speed controller to be really quite good. I can not vouch for the gold top motor and mystery speed controller that came with my SE kit. I'm so afraid to use those components I pretty much chucked them and forgot I got them.

Delfin has been quite good about fixing issues for customers including myself. Have you sent him an email directly?

05-27-2009, 08:01 PM
Now that the Trex PRO is out there are a bunch of little upgrades for the V2 SE that are popping up so I decided to check and see if these worked on the Flasher.

I've been spoiled a bit with my GAUI Hurricane and RCer Dragonus and have had the pleasure of dealing with lots of fixed linkages on the head that make setup an absolute breeze. The new Trex PRO is also using fixed linkages for the flybar->main grip and washout->flybar cage so I picked up a set of the linkages to try out. The first set I bought are the ones designed for the Trex PRO as no one had the other set. The set for the PRO has 2 long linkages and 4 short linkages. You only use the 2 long ones and 2 short ones. As you can see by the measurements in the pictures the short ones are about the right size while the longer ones are longer than recommended in the manual. I put these linkages on my PE kit. They seem to work quite well.

Today I was at the hobby shop and they had a few sets of the V3 upgrade linkages as they call them. This bag only has 2 short and 2 long. I have read that the linkages in this kit are different sizes and are designed specifically as an upgrade to the V2 SE kit. I will compare the linkages tonight and will report back if they are indeed different.

The second upgrade I got is the Trex Pro washout base. There is a little slop in the Flasher SE and PE versions of the washout base so this was a cheap $8 test. This was not a direct drop in on my Flasher. The flasher washout guide pins on my kit are apparently a little thicker than the ones that are on the Trex PRO. I filed the pins down a bit with my dremmel and cleaned them up with a jewelers file and it works great. If you have some slop in your washout base and would like a nice upgrade I think the PRO base works well.

While I was at the LHS today I also spied the new PRO tail blade grips. These come with the integrated Chinese weights so I picked up a set for $20. I will report back when I have a chance to install them.

Finally, I saw some CF main blades at helidirect for $18 and they got really good reviews so I just could not pass them up. These blades are really nice. Both blades are incredibly well matched with the weight being exactly the same at 17.6g. The CG on both is also identical. I've not had a chance to really fly them yet as I'm working on an electronic issue at the moment on my SE kit (a servo went bad and is causing my receiver to overload) but I can't wait to fly these. I got the new servo today so all this should be installed and ready for a test flight this week. The last pic is the heli with the blades on.

Link to the Blades: http://www.helidirect.com/high-quality-325mm-symetrical-carbon-fiber-main-blade-trex-p-576.hdx

05-27-2009, 09:01 PM
Interesting. What parts didn't work on the tail for the PE?

Which motor/esc did you get? I've found the ICE motor and MKS speed controller to be really quite good. I can not vouch for the gold top motor and mystery speed controller that came with my SE kit. I'm so afraid to use those components I pretty much chucked them and forgot I got them.

Delfin has been quite good about fixing issues for customers including myself. Have you sent him an email directly?

The tail housing and grips look just like the metal parts sold for the SEV2. But the only plastic tail parts sold locally in any of the 4 LHS I checked were for an SA-style tail. Metal parts for the tail were 40+ so am just ordering the metal Flasher instead.
I sent an email to snhobbies a few days ago but have not received a response.

I'm sure curious about the fixed linkages - Finless Bob has a whole section oriented around aligning the swash and linkages using those adjustable ones. So I wonder how the alignment will work out!

05-27-2009, 09:18 PM
They work out fine. You only need to adjust the pitch and the swash to servo linkages. I've already done this on the PE and it was a non issue. I just levelled the swash as normal and then installed the head and set the pitch and was done. No need to fiddle with the rest. The head will be square since those linkages are fixed. What it does limit you is adjusting the mixing ratios. If you never changed them by adjusting those links and only kept them at the recommended lengths in the manual then these are a good replacement. From what I've read the bags I picked up today are direct replacements. The one's I'm using right now that come with 6 linkages in the bag required my swash to be adjusted a little.

You can use the old style blade grips from the S or SA if it was the grip that broke. You can mix and match tail parts a lot on these things. The tail pitch slider is plastic on the SE so that part is pretty cheap. Unfortunately it comes in a kit with a lot of other parts. The SA grips work with it though.

I had sent emails thru the website and had not gotten a response as well. Try emailing him directly. I will PM you his email address.

05-28-2009, 12:07 AM
Whoami, seems you have pm's disabled.

05-28-2009, 05:31 AM
So I got the new items installed tonight.

First up was the new linkages. The V3 linkages are definitely different from the PRO linkages. Right away you can tell that they are not nearly as bulky as the pro linkages. The pro linkages also have an A on the side that goes away from the ball. These linkages simply have align etched in the side that go away from the balls. They are also different dimensions. The short links are a smidge longer than the ones in the pro kit and the long links are shorter than the ones in the pro kit. These linkages almost match the lengths given in the manual but not exactly. The long links are still a bit longer than recommended in the manual. Other than that they were a drop in replacement on my SE kit. I had only installed the short linkages. One turn on the pitch control link and all was the same as before.

The tail hub upgrade was simple. Took maybe 5 minutes with picture taking. Just remove the old one and install. I've never flown with Chinese weights before so I'm really looking forward to seeing if I can feel a difference.

06-06-2009, 01:14 AM
Received my 450PE today. No instructions at all with the kit ? Came with one pinion gear 11T, I don't think that's right. Other than that it looks pretty good. This is my first heli, a manual would have been nice.

Jim R

06-06-2009, 05:04 AM
My PE Kit didn't come with instructions either. Only the SE kit came with instructions. You can use a T-REX SE V2 manual as the instructions. If you have a helifreak account you can get it here:


If you are using the motor that is included with the SNHobbies kit the 11 tooth would be correct. My PE kit came with a 13 tooth and that is way to much for the 3500kv ICE motor on the plastic head. The 11 tooth is a much better choice.

If you have any questions please ask. I've built both the PE and SE kits. Good luck and I hope you enjoy it :)

06-06-2009, 05:25 AM
My PE Kit didn't come with instructions either. Only the SE kit came with instructions. You can use a T-REX SE V2 manual as the instructions. If you have a helifreak account you can get it here:


If you are using the motor that is included with the SNHobbies kit the 11 tooth would be correct. My PE kit came with a 13 tooth and that is way to much for the 3500kv ICE motor on the plastic head. The 11 tooth is a much better choice.

If you have any questions please ask. I've built both the PE and SE kits. Good luck and I hope you enjoy it :)

Thank you, I'm using the ice 3500kv motor so I will go with the 11T pinion. And thanks for the manual.

Jim R

06-09-2009, 03:56 PM
I've been following your thread on rcgroups, LostSoul. So haven't been around here in awhile.
An update. Flasher SE finally came off backorder and I got mine last Friday. Spent the weekend working on it.
First impressions were good. Seems well constructed. Now if it can survive my fat fingers!
I am sorry but this is a negative account. I know you've got a much higher regard for this model. Perhaps I expect too much and, being a beginner, would hope I can fly at least half as much as I repair.

I built the PE kit first. About a month ago. As I mentioned then, I couldn't keep the tail steady in my first flight. Landed a little hard in the grass and suffered much more damage than I would have expected. I reiterate a bit because the tail damage on the PE was not replaceable with LHS parts unless I upgraded to metal. Hence the SE choice.
This SE metal tail LOOKED great! But I can't keep the tail grips tightened down on the hub without losing ease of rotation. And this is a big problem because, like Mike on your rcgroups thread, (and you as well at one time) the vibration on the tail is HIDEOUS and makes the model unflyable at this point. I've gotten to low hover by throttling through the worst of the vibration (left-right indicating tail problems - I did homework on the RcGroups links). But the vibration is rattling the tail parts loose (and all the others too - despite blue locktite) to the point the grips stop responding to the gyro and the model starts spinning. The servo can't overcome the force of the jammed grips! I've tried a tiny bit of locktight on the screw ends. Vibration still shakes them loose. Too much locktight and it gums up the bearings in the grips. The bearings don't have a surface on the hub to press against because the grips and the hub rub together when screwed too tight. I'm considering an Align tail grip but that is expensive and looks like the same design. I'm dismantling and reexamining everything. Like Mike, the vibration reduces dramatically when I remove the blades from the grips.

I'm still trying to use the ICE 3500 motor that came with the PE and it pulses about twice a second - sometimes. When this happens, I get a weird vibration from the front. Sometimes it runs fine (except for the tail vibration). I swapped out the MKS 35AH ESC to see if that was the problem. Got an Eflite 40Amp and tried it. Pulsing still there. I swapped out the gear for a stock Align. That stops some of the vibration and, when I disconnect the tail, everything is smooth except when I get the pulsing. NOTE: I've NEVER received a gear from SNHobbies that wasn't warped. I've bought 3 now and the top gear oscillates enough to shake the head. Pulsing contributes to that. I have an Align 430XL on order (nobody locally has them in stock) and will see if that runs smoother. The only response from SNHobbies was "Motor and ESC don't pulse, check your shaft and gear". Then, when I mentioned the warped gear, he said "Press the bearing like the video online". No help and no support, last time I buy from SNHobbies. They NEVER agreed to replace ANY of this defective equipment. How you got Delfin to help, I'll never know.

Anyway, I've considered a metal boom but the metal ones are an inch shorter than the CF (the align one - the Flasher ones for PE are the same length). I got the PE because it was cheap, not because I wanted to throw away new parts and buy more expensive ones!

The thing is, I'm beginning to doubt that buying the Flashers was such a good idea, given that I'm having to buy stock Align parts to fix problems these models shouldn't have! I'm even more uneasy with those who might say the TREX 450 has just as many problems.

I went to the TREX line because the CPPRO2 doesn't have spare parts yet (they promised them in May and now say July) so I can't fly it (can't get a new motor and the tail blades that are alternates are not really that strong, so tail doesn't hold).

I saw your flight video - you make flying look easy! I can hover and FF but that's it - only flying since January. With this PE, the vibration is so bad that the model dances across the garage and I'm afraid to get it off the ground. Haven't given up yet but am thinking about it.

Those that take this type of trouble as fun must be flying something else, or have deep pockets to keep buying new parts to replace stock brand new parts out of the kit!

Sorry, a little ranting from a frustrated nubie.

06-09-2009, 04:57 PM

I'm sorry to hear your experience has been poor.

On the tail problems on the PE. Which part broke on you? I believe I asked this on the RCGroups thread as well and I've not heard. You can mix and match tail parts a lot. You should not have had to buy a complete SE tail setup to fix the PE. There are lots of options both after market and straight from align to mix and match to fix a tail. The SA blade grips should work on the V2 tail. I think the only thing that wouldn't work is the pitch slider since that's a different design.

I used red threadlock on the tail blade grips on mine. I've had issues with Align tail grips doing the same thing and on certain parts I've always just ended up using red threadlock. I've never had any bad vibrations in the tail though. The align grip is the exact same design so it's likely you will have the same issue that you have now.

I wish I could see these heli's and help out in person. Did you completely tear both of the helis down and build them back up? Some of the people that have been having a lot of trouble didn't take the time to dismantle the heli completely. I truly wish this heli came as a kit completely unassembled. I think that would solve a lot of these issues.

That is strange that Delfin didn't replace the ESC for you. Obviously I was not involved in the conversations so I don't know what the exchange was. He's always given first rate support to everyone I've talked to. You're the first I've heard that didn't.

It is a known thing that the Flasher boom is a little longer than the align. To swap out to the Align boom you need to buy the align belt as well. Obviously there are some things that can't be identical to align. The boom length is one of them.

If you have the ability to post pictures of your helis with the problem areas you are seeing I would be happy to look them over and see if there's anything I can see.

06-09-2009, 08:36 PM
Thanks, your comments have been very helpful already.
I'll try the red threadlock.
Engineering-wise, a shorter boom would change the balance a bit. But it would also shorten the belt length and that might change the harmonic vibration frequency. Though it would likely increase the frequency, it should lower the amplitude. (just thinking out loud)

The housing (the cylindrical part that slides onto the boom) is what broke on the PE tail rotor. Unfortunately, to replace that, you buy the whole assembly, which is metal (unless you get it from SNHobbies, I guess). The plastic parts available at the LHS are for the earlier design tail and they only had the plastic parts, not the screws and shafts. I tried to mix and match but the grips were shorter and, while the shaft was the same, the various arms had different connections.

You're right, I only partially reassembled the kit. I threadlocked the frame and worked over the tail rotor but didn't completely disassemble the head. One of the posts in the boom holder had a stripped side out-of-the-box, so I've got some potential source of problem there (though the boom is not loose). I haven't had any trouble with the head, though with all the other sources of trouble, I just might not have it smooth enough to notice.

You wouldn't believe how wild this thing scoots on the floor at half throttle. Like it is on a hot plate. It slides two car-lengths one way with me giving aileron tipping it over the other way. It is a little more stable in the air, though.

I'll let you know if I fix this thing but I lost a servo of my own and am waiting for a replacement (JR DS285), along with a new motor, so have time to rerebuild. If I can get the new motor to behave, I can at least prove to Delfin that the problem was the motor. Then again, I said that about the ESC, didn't I?

06-09-2009, 09:02 PM
The shorter tail boom and change of boom material will change the resonant frequencies a lot. Would be a completely different ball game. T-rex's are known to have this resonant vibration issue with CF booms. For some they could never get rid of it with the CF boom and dropping down to the aluminum one was the only solution. I have no idea why that is. I can say it does seem this heli has the same potential issues as an Align T-rex. Makes since as it's practically identical.

Is this the part that broke?


If it's that part I'd probably just get it from SNHobbies. At only $14 shipped there really is no cheaper solution. How did you manage to break that part?

It's hard to really tell if what you are seeing at half throttle is unusual. Depending on how tight your main blades are in the grips half throttle usually is not enough to get the blades straight. No matter how hard you try you just can't get them straight by eye :) So you will see the heli bounce around a lot at half throttle on the ground.

I run my normal throttle curve like so (only use a 3 point curve): 0 - 70 - 90

That gets the head speed up quickly so the heli moves around as little as possible on the ground. I've got the MKS speed controller on my PE kit and it's worked well for me. It has a pretty nice soft start on it that helps smooth that throttle curve.

I used to have a problem with pulsing with my Dragonus motor. It usually happened if I didn't get the throttle up fast enough. I had to change the timing on my Jeti controller to get it to work reliably but it still pulsed from time to time. Once it was spinning it was fine though. I've not had that problem with my ICE motor but I've got it on the Spin controller and I am running the same timing that I had on the dragonus. I didn't bother changing it. I did try the MKS with the ICE motor when I got them and don't remember any issues out of the gate. I don't know if you can program the MKS speed controller to adjust the timing. I'll look into that.

06-10-2009, 03:47 PM
Yes, that's the part, the round housing sheared next to the transition to the square section. I lost tail stabilization in the wind (I guess) and was low to the ground, so didn't have time to recover. I suspect the damage would have been less had it hit something harder but the soft grass tends to grab these things and hold on quickly. Bent the aluminum tail boom into a Z pattern and took the tail with it. Bent the main shaft and stripped the main gear. That's one big thing with the 450's, lots of mass combined with speed and you can't cut the throttle to save it in a crash like on the smaller heli's. Head keeps spinning for 30 seconds after that!

I'm guessing I should have bought that tail assembly back after the crash but when I couldn't find parts locally, I started evaluating whether this was a good thing to do. After all, waiting for 1-2 weeks between flights for parts to arrive wasn't a good use of flight time (expecially since my total flight time was 5 minutes prior to crash!) So I decided to get the SE because the LHS had parts that more closely matched it. And hopefully, the metal stuff wouldn't damage (though if it did, that would be more expensive).

I'll try your advice on the higher speed. It might be a Catch-22, though, since
1. I need more head speed to cut the vibration
2. The higher the speed prior to +pitch, the more it drifts on the floor (concrete).

I'm at about 65% at half stick, so can definitely increase to try it out.

The MKS ESC (I got the better Engrish for the instructions off their web site) just programs the brake. I've tried it and like it as well, though it has high torque on throttle cutoff, which hurts during bench testing. I think I have a bigger problem then pulsing with the motor. The motor sometimes doesn't even spin up with throttle, kind of like the gear is binding with the pinion (only I can't spot the source of binding). Then suddenly it kicks in after toggling the stick. Anyway, the new motor should be in soon and I can test things by process of elimination.

But I already have the metal Align boom and will get the short belt and see if the combination helps at all and maybe I'll actually get airborne! Just not this week as I'll be out of town for a few days.

06-23-2009, 06:02 AM
Well, after several attempts, purchases, returns, and a few leftovers, I've finally found a belt that fits the shorter boom. Apparently the part is for an XL. None of these had any indication how many teeth or what boom they fit, though Heliproz seemed promising. But the LHS (we have 4 within 1/2 hour drive) had two old ones and knew just what I needed. Anyway, I put it on and it fit. Also I had trouble with the pitch rod, since it was made for the longer boom. I got it to fit by rotating the servo so the shaft pointed forward and then slid the mount to within 1/8 inch of the boom mount.
BUT, it fixed the vibration! A very good example of how these forums can save a heli! I've flown it to be sure it is doable but it is still too unstable to play with much. I've got to do some more threadlocking and swash leveling and pitch adjusting before I risk another crash on faulty equipment. I've also been flying my Blade CP Pro2 a lot more, since I got the gyro to work with the GWS tail rotor blades. Bought another supply of them and want to practice some more on a cheaper machine (those crashes cost $10 in parts while the 450 is orders of magnitude more). Plus, even though the tail parts on the CPP2 aren't being released until July (so they say) I have some alternatives that don't cause it to crash.

06-23-2009, 10:04 PM
Glad to hear that the new boom fixed the vibration so that's good.

Good luck getting it tuned up. One of the joys of heli flying. I'm constantly tinkering with my helis. Wife hates it lol.