TRex 450 SE nV2 to 500E Makeover ...

[warpspeed]

Wow, that second pic really illustrates just how far off they mounted the plate! Since they've got to be leveled anyway, what do you think about using a hard rubber shim under the supplied mounts to dampen vibration? Having the nose fall off does NOT sound like fun to me.

I know most are building the civilian version but I'll throw this out there anyway-while I'm waiting for my lights to arrive I've been trying to track down scale armament; either machine guns to hang out the doors or missile pods. Does anyone have any idea what scale this fuse is, or an approximation?

BTW, I wanted to thank everyone for all the pics and great information, and apologize to RChristopher for hijacking his thread. I agree it should be made a sticky!

[crazyerick]

Hahaha, yes my nose popped off the first day cause I had a vibration. The elevator servo was rubbing against the top of the fuse (curve). To fix the vibration I remounted the servo from inside the frame and used the dremil to notch out a piece of the one corner of the servo case. I then glued foam onto the servo case, and another piece on the inside of the fuse (opposite side of the servo) to counter the servo foam, as it was pushing it off centre.

I fixed the front cover by adding one of those rare earth magnets. Now no problem.

[DDragon]

I emailed the Dog and he kindly made this a sticky. So lets put all important information in this thread!

[DDragon]

The main reason that the helicopter is spitting the canopy off is vibration. The most lightly cause is the wooden stacked mount for the frame. Mine delaminated after a few flights, when it let go in flight things got interesting really quickly. I remade them in aluminium....big mistake! This set off a resonate vibration that was uncontrollable. I remade the original mounts and glued 1mm ply either side of them. It is also important to make sure that you have a firm contact all the way along the mount. If the base is out of wack glue a strip of wood on the bottom of the mount and sand it so as to make the mount level, I know it's easer to use washers but this can induce vibration. I have done the above mods to my 500E and just logged it's 50th flight today and all is well. Although extra magnets would not hurt!
Bob, Your panel lines came out well

I'm just building mine now. But I'm wondering if making them out of rubber in the same method as a engine mounting block would work? You could get either a big rubber cord from home depot or some of those rubber stopper things that you put under furniture so they don't scratch the floor?

I think I'll try the rubber corks first, if Home Depot doesn't have them I can get them from a wine or beer supply store. They come pre-drilled for the mounting studs! :YeaBaby:

[DDragon]

"supplied mounts to dampen vibration?"

Sorry just read this... didn't know someone already thought of this.

[DDragon]

Wow, that second pic really illustrates just how far off they mounted the plate! Since they've got to be leveled anyway, what do you think about using a hard rubber shim under the supplied mounts to dampen vibration? Having the nose fall off does NOT sound like fun to me.

I know most are building the civilian version but I'll throw this out there anyway-while I'm waiting for my lights to arrive I've been trying to track down scale armament; either machine guns to hang out the doors or missile pods. Does anyone have any idea what scale this fuse is, or an approximation?

BTW, I wanted to thank everyone for all the pics and great information, and apologize to RChristopher for hijacking his thread. I agree it should be made a sticky!

You could try a plastic model kit from a model store. I'm sure the guns would look pretty good and it won't be too hard to find a helicopter the same size.

[Gra55h0pper]

Since they've got to be leveled anyway, what do you think about using a hard rubber shim under the supplied mounts to dampen vibration? Having the nose fall off does NOT sound like fun to me.

That might work, but could actually also make it worse... With resonant frequencies it's just very hard to tell.

My theory (there are many though :D) is to firmly fix the bottom of the mechs to the base plate in the fuse and then allow the top of the mechs i.e. rotor-head and the top-of-the-fuse & tail-boom to each vibrate freely in their own resonant frequencies. This is why I think it is very important to ensure nothing on the mechanics is touching the fuse. As long as the mechs and fuse resonant frequencies do not amplify eachother :thinking, you should be OK. That's my theory anyway... :D

Of course the first thing to do is to try to reduce the vibration as much as possible by making sure the main blades are properly balanced, not only weight-wise but also CG-wise.

[Blusaber]

My 500E is coming tomorrow and I currently have a 9650 tail servo if I want to downsize for an easier fit what do you guys think would be the minimum acceptable torque 12oz 25oz ?

Gary

PS took me forever to find this thread lol passed it by since it was a sticky at the top even tho I read it was being asked for did i feel stupid

[RChristopher]

First off, let me thank HeliFreak for making this thread a sticky. A lot of great information has been contributed and collected here. Thanks everyone!!

Just a couple of items I thought I would comment on. Regarding the standoff delaminating, I had this happen when I was testing the 350mm blades. Now I have one medium size cable tie going through the 450 mid frame and through the holes in the plywood base just as a security back up. The attached pic was from another post.

http://i14.photobucket.com/albums/a328/n50482/Helis/RearScrew2.jpg

Another item is securing the top portion of the mechanics to the fuse. On mine I went for a dampening effect rather than a rigid attachment. I used a small piece of minicell foam to fashion a secure damper. Shapped roughly like a crescent moon, the ears fit up under the fuse, with two slits on the 450 frame side matching the frame location. I just have it slipped in place and it holds securely. I could use velcro on the outer edges, but really haven't needed to yet.

http://i14.photobucket.com/albums/a328/n50482/Helis/FoamDamper.jpg

Regarding vibration, make sure you have taken care of all the typical sources. Make sure you've got all blades (main & tailrotor/ flybar) balanced and tracking well. When trial fitting and assembling check everywhere to make sure nothing is rubbing. Don't overtighten blade retaining bolts. Monitor main blade damper condition, and so on ...

Best to all!!

Bob C.

[kingkahuna]

My 500E is coming tomorrow and I currently have a 9650 tail servo if I want to downsize for an easier fit what do you guys think would be the minimum acceptable torque 12oz 25oz ?

Gary

PS took me forever to find this thread lol passed it by since it was a sticky at the top even tho I read it was being asked for did i feel stupid

I am using the same tail servo that is used in the Blade400, it sucks compared to the 9650 but that is the price of scale flight.

[Snoopy6]

I just want to (along with Bob) add my thanks to Helifreak for making this thread a Sticky! This is a great forum and such a tremendous help to those of us just getting into helis AND scale flying. :noteworthy

[Blusaber]

Well the 500E came today and I must say all the pics really don't prepare you for the size this thing is going to be cooool

Only problem on both sides the front wind screen was cracked pretty bad. It's underneath and doesn't really show unless you turn it upside down or tilt the nose up. These things are so scarce I didn't want to send it back or make an issue of it so I used zap gap on the inside. Not real purdy but the strength is back and that's all I wanted.

On the bright side the platform inside is dead level. I don't want to fool around with mounting the 9650 different so I'm going to put a Futaba 3114 or 3154 on the tail. I just want to cruise around so I think either will work ok for me. Over all I'm kinda amazed at what you do get for the price. Hope I don't get the big heli bug just cause this looks so cool flying.

Gary

[Snoopy6]

Woohoo, my 500E Fuse just arrived too! I have to agree with Blusaber, it is bigger than I expected. Noting is cracked or broken and the mounting platform for the mechanics appears to be dead level. Will put a level on it later when I get down to serious business. Right now, if I want to sleep inside tonight, I have to do some outside chores. :YeaBaby:
I think my better half already suspects I have a girl friend since I spend sooo much time on these forums. So if she asks, I'm gonna just say "yeah I do, her name is Miss Helifreak! :rolling

[Snoopy6]

I read the posts concerning the standoffs delaminating and some of the solutions to prevent that happening, so here's my question: I figure I can "paint" a thin layer of epoxy glue all the way around the standoff rather than gluing on a piece of thin plywood....what are your thoughts (anybody)?

[Brent@paradise]

Hi Snoopy6
Yep thats what i did, but guling a piece of thin plywood is a better solution.

[Blusaber]

Well shes together and survived her first few flights. I went with the Futaba 3154 for the tail when I opened the box I was amazed how small it really was. Flies great with it, no binding or trouble setting it up in rate mode. I run a 5 volt bec and won't be stressing it so I hope she holds up.

Did have one mishap I used Zap Gap on the tail pieces, that did not go so well I was in a hover saw it start to fail and before I could land it wound up in the tail rotor. Dinged a small spot in the leading edge. I redid it with epoxy this time and it's much more solid. Will take vids tomorrow. Between the wind screen arriving damaged and my tail nick shes not pristine but that gives her carractor.

Gary

[RChristopher]

Congrats on your first flights Gary! Looking good.

Bob C.

[Blusaber]

Ok

On my fifth flight as soon as I lifted off I knew something was not right, lots of chattering and noise circled around and landed. Back spacer block had completely separated ant the front was 3/4. I had read where this could be a problem but had done nothing. My fix was to epoxy the blocks back together and coat the entire out side with epoxy. I filled the center hole with epoxy. I'll see how this works out. It seemed to fly better after this so from the start It may have been coming loose. Whatever method you use these need attention from the get go IMHO .

Heres a quick vid of it in the back yard after the fix

http://www.youtube.com/watch?v=SyiOSpXxl_Q


Gary

[Snoopy6]

Nice vid! It really looks great; I'm just getting started on mine tonight.....Was doing one last flight today before starting build and had a minor crash: blades, flybar and shaft. Hope I got that outta my system for a while!

[Blusaber]

Boy lets hope so. I at least want a lot of bug juice on her before I crash. I mainly wanted to just cruze around anyway so hopefully crashes won't come soon.

Gary

[Gra55h0pper]

Done! Isn't fun-scale fun... :D

[ObiDon]

Yesterday I finished the 500E and took it for a test hover in the backyard. I noticed that it was really tail heavy when I picked it up. I threw a small bag of lead shot into the front of the canopy and decided that it was close enough to being balanced.

After spooling up I noticed that I had already pushed the throttle stick way past where my stock T-Rex would have taken off and this guy was just getting light on the skids. I managed to get her off the ground all though hovering about wasn't much fun. It no longer had that crisp, smooth in control feel that I'm used too. About 2 minutes into it I see the tail coming around without input from me to do so. I'm not sure what exactly happened next. I couldn't stop the tail from swinging around on me and I crashed. Luckily the body wasn't damaged. I ended up with a stripped 56hb on the aileron, bent flybar and busted blade.

After making the needed repairs and kicking up my throttle curve I was ready to try again. Once again, not a lot of fun. The higher headspeed had it up off the skids quicker. But it seems like a real handful. I can't seem to keep it in one spot and the cyclic response seems twitchy. Maybe that's the higher headspeed? I'll try adjusting the dual rates.

I have two ounces of lead wheel weights taped to the inside of the canopy and the tail still still hangs to the low side when I lift from the blade grips. Any ideas on how to make this more fun to fly? I feel like I'm chasing it around the yard right now.

Don

[RChristopher]

Wow Gra55h0pper, great looking ship. I am going to try some of the Do It Yourself decals for some basic items such as "Danger" and fuel caps, and whatever else pops into my head.

Don, for what it's worth you might check page 6 for a listing of the setting I am using. Just as a reference to compare against.

Good Luck!!

Bob C

[RChristopher]

I just wanted to emphasize the need to beef up those standoffs. As we have seen through several posts, they have a tendency to delaminate,especially if assembled using just CA. I had my second occurrence of this today on the front standoff. Luckily I had a cable tie backup.

I would suggest stregthening the standoffs as part of your original build. Some have used a layer of epoxy on the outside surface, as well as the inside cavity. I would suggest a layer of fiberglass or thin plywood to act as a web to tie all layers together.

Mine did not totaly split, only half way, but she was really shakin!! I didn't want to tear her down right now, so I applied cable ties to the four corners. Appears to work fine. I will be applying front and back plywood webs to both front and back standoffs on my next tear down.

Cheers

Bob C.

[Gra55h0pper]

Obidon -- I flew mine today and I'm very happy with it! It is a bit heavier of course but that's normal for a scale ship. I find it still has plenty of power for flying around at good speeds.

Couple of things:
- On a helicopter, even though you prefer to have the CG over the main mast, it really isn't that critical. Not at all like on an airplane. It probably shouldn't be *way* back, but my experience is that it can easily be as far back as 25% of the rotor length. Guess what I'm trying to say is that you may want to consider having a lighter heli with the CG aft rather than a heavier one with the CG spot-on. Of course, you'll have to trim it forward on elevator a bit.
- One thing you could do is create a battery tray which extends from the fuse-floor forward. This way you can get the battery to go further forward into the fuse which should fix your CG
- Of course, having a "decent" power package helps with the flight characteristics. Even though you don't need that much I think. I have a V2 with the Align motor on 3S (Thunderpower 2200) which works fine.
- Don't exepect to be doing tic-tocs, chaos, etc. :D Loops and rolls are not problem but I doing so doesn't look right in my opinion.

Not sure about the problem you were having with the tail. My 401/9650 combo seems to be having no problems at all with the heavier bird.

A friend of mine shot a video today. I'll post it.