450 Align TRex 450 Pro v2 3 GX build

[Tomhintz]

A momentary distraction has spelled disaster for anyone who has flown helos, fixed wing or congtrolled anything with a radio. I have a friend who races hand built 1/8 sprint cars that hit 100 mph (actual, speed gun) on a scale 1/2 mile track. An accident happened in front of the drivers stand when he was on the back straight and he glanced down to see wnhat happened and drove the car straight into a concrete block wall. Broke a fully hand made chassis in half, killed a very expensive notro motor and mangled three custom turned wheels and tires. Well over $1500 worth of damage done by one glance.
It happens, fix it up and move on. You are now the least likely among us to allow themselves to be distracted with a helo in the air.

 

[Slobberdog]

Dude what did you feel was not right, I have about 10 flights on mine and it feels pretty solid, hope you get it back in the air soon and more importantly how you like it,

 

[Chompwat]

The sticks felt pretty vague by comparison to what I had been doing.
I'm certainly not blaming the set up. That was purely down to my distraction.
I had been flying on the default settings which felt very locked in.
Off the top of my head I had the damping at 30% on the 3GX and zero expo on the sticks.
I generally fly with around 10 - 15% expo on my planks and micros.
I think the default is zero so that's quite a difference.
When I've rebuilt it I'll go back to default and add the changes you guys are using a step at a time instead of all in one hit.
Trust me, after a repair bill like this my concentration will be at 110%.

 

[murankar]

Are people using a tach to measure head speed?

I use my phone with a head speed app which is like $5. Their is a math equation you could do or you could use a tach.

 

[Tony]

Are people using a tach to measure head speed?

Nope, most are just using calculations.

KV*voltage=total motor rpm

motor rpm / gear ratio * .8 = head speed at 100% throttle

If your running a 60% flat curve, then multiply the above sum by .6, if using a 85% flat curve, then multiply by .85. Hope this helps.

Hi Guys. I've not been on for a few days due to being in a period of mourning! For my newly built heli that is.
Having had 8 successful flights on the default 3GX flight settings I decided to try the settings that we had talked about earlier in this thread.
Disaster.. I hadn't given any thought as to how different the heli would feel. Only a few seconds in to the flight I wasn't enjoying the experience, and I let my thoughts distract me. In she went on the right hand side from about five feet, and I just didn't react fast enough. Bang!!!
I immediately hit TH but I could tell it was heavy as my new bird lay there twitching and buzzing as the gyro was trying in vain to work the servos. And where was the tail rotor unit?
It took 4 days before I could even bring myself to examine the wreckage.
Now that I have my worst fears have been realised. If it can be bent it is, if it can be stripped it has.
Main blades trashed. DFC linkage bent. Main shaft bent. Main gear stripped. Top main bearing now feels gritty, no doubt due to the side load placed on it. Skids cracked. Tail boom and torque tube bent beyond recognition. Forward TT drive gears stripped. Tail rotor shaft bent. DS 425 gears stripped. Pitch and elevator servos also have a slight click to them, though I've not stripped them yet.
Total repair cost not including servos is £72 GBP, about $110 USD plus delivery.
I am confident I can repair the tail servo, but I have yet to look at the cyclic servos. The gears sets are almost the same price as a new servo.
Oh, and the tail rotor unit was about 70 feet away having cleared a four foot fence!

I was gutted as the flights I had were all positive experiences with a feeling of complete control.
I have yet to declare the repair bill to my wife!

That is a real bummer dude! Hope you get it back in the air soon.

If I may, what was the issue with the new settings? Too sluggish? Too responsive? Let me know. The more information I can get on the 3GX setup from different people, the better I can help those in the future.

 

[Chompwat]

That is a real bummer dude! Hope you get it back in the air soon.

If I may, what was the issue with the new settings? Too sluggish? Too responsive? Let me know. The more information I can get on the 3GX setup from different people, the better I can help those in the future.

Thanks Tony. As I explained to Kev earlier, for me the sticks felt quite vague and not as responsive as I had become used to. That was with the damping at 30%.
I'm sure that was not what caused me to lose control, it may have had an effect on how I reacted to it in the amount of stick response I gave.
I remember thinking, I don't really like the feel of this, instead of concentrating 100% on what the heli was doing.
I am used to quite low expo settings, and as the damping In the 3 GX settings has the same effect as expo at the sticks I think this is what I wasn't gelling with. My stick expo was still at 0.
When I get it rebuilt I will try changes one at a time on low hovers to see how it feels.
I think that making all the changes at once made the heli feel too different.
I may try the damping at 0 and expo in the Tx at 15% which is nearer how I fly my 130x. I think Kev has his set up something like this!

I hope that all makes sense!

 

[Tony]

Makes perfect sense bro. The settings that I lay out in the videos are VERY tame and do make the heli sluggish, which is great for a new pilot that needs something that is not just bouncing all over the place. It gives them time to think.

For you and not liking much expo, I would suggest turning dampening down to 0 on both collective and cyclic, turn your roll rate up to 50% and turn your cyclic pitch (where the swash tilts as you are setting it up) to about 40%. I think this would be more to your liking. It will be MUCH more responsive, but not so much that it's uncontrollable.

I would suggest though, for your first flight, put in about 30% dampening on the cyclic. That would give you about 10% on the collective since they must be within 20% of each other.

Hope this helps. Sorry for the crash.

 

[Tomhintz]

Got my TRex 450 Pro with the BeastX out to the flying field yesterday and had it looked over by a guy who flies lots of helicopters. He has a Trex 500 with over 300 flights on it and it loks brand new! anyway, he liked what he saw, I took it up and hoved around in some pretty stiff winds and it did well. He took it up and flew it around and said that i had it set up well and that it handled well, then it bounced int he wind as he was landing and shot out the forward tail rotor gears again!
I am going to find something to make this thing more grass friendly. It really does not take much of a bump at all in grass and the tail rotor gears start shedding teeth. I ordered some trex 500 gear and vertical stab just to see if I can modify them to go on here to get the tail rotor up just a bit more. There has to be a way to fix this so it can land in grass with less strain!

 

[Tony]

I can assure you, the 500 gears will not fit, the pitch is different on the gears and the shaft size is different as well. You best bet is to get some black gears. I have (had) them on my 450 and I ate the grass and sidewalk a few times and I"m still running teh same set. Hell, I had a crash with that bird and they look brand new. Black gears are the way to go on the tail! Toss those white ones in the trash.

 

[Tomhintz]

I can assure you, the 500 gears will not fit, the pitch is different on the gears and the shaft size is different as well. You best bet is to get some black gears. I have (had) them on my 450 and I ate the grass and sidewalk a few times and I"m still running teh same set. Hell, I had a crash with that bird and they look brand new. Black gears are the way to go on the tail! Toss those white ones in the trash.

Not the gears, the landing skids from the 500. I know the gear sets won't fit. I expect to have to modify the skids as well but for the price thought I'd get a set and see what it might take to make them work. I had a black umbrella gear in it and it was the one that broke! It shed three or four teeth and the stock white gears seem to be fine, maybe rolled off just a tick but without magnification they seem OK. I will be tearing it down shortly and I just heard from the guy who banged it up and he has a new set of gears if I need them that I can put in at the field later on today.

 

[Tomhintz]

I can assure you, the 500 gears will not fit, the pitch is different on the gears and the shaft size is different as well. You best bet is to get some black gears. I have (had) them on my 450 and I ate the grass and sidewalk a few times and I"m still running teh same set. Hell, I had a crash with that bird and they look brand new. Black gears are the way to go on the tail! Toss those white ones in the trash.

Not the gears, the landing skids from the 500. I know the gear sets won't fit. I expect to have to modify the skids as well but for the price thought I'd get a set and see what it might take to make them work. I had a black umbrella gear in it and it was the one that broke! It shed three or four teeth and the stock white gears seem to be fine, maybe rolled off just a tick but without magnification they seem OK. I will be tearing it down shortly and I just heard from the guy who banged it up and he has a new set of gears if I need them that I can put in at the field later on today.

 

[flysolo]

I never land on grass, or if I have to I always hit TH 2 feet above the ground. Saves A LOT of umbrella gears, I used to change them all the time both black and white ones.

 

[Tomhintz]

I never land on grass, or if I have to I always hit TH 2 feet above the ground. Saves A LOT of umbrella gears, I used to change them all the time both black and white ones.

I have been doing the TH landing deal but need to get better at it. I have a welcome mat that I have been putting on the grass at home and landing on that but until I got the BeastX installed, hnitting that little mat was a problem itself. But, grass landings are my reality so I am going to find something to help that, eventually, I hope.

 

[flysolo]

OK, it's just keep on practicing then My landings are not perfect at all but the nicest ones i get when the landing area is absolutely level and I just use collective to land. The conditions have to be good for that to happen, if it's windy or I'm landing in grass the other method feels safer.

 

[Chompwat]

I have ordered the black torque tube gears as my replacements.
It seems the front set of gears are the ones that take the greater forces when the tail rotor hits. At least they are inexpensive and are easy to replace. The problem with reinforcing a weak point is that the damage will just be displaced to another part of the train. I do agree though that the white gears strip a little too readily. This seems to be common with all torque tube drives.
Thanks for the suggestions Tony. I have decided the training gear will go back on while I play around with settings.
I shall order the parts this week as I am off work Friday and hope to start rebuilding then.

Sounds like its all going well Tom. I had just got to the stage with mine where I was enjoying some easy FFF just going from left to right about 50 feet out either side from me with simple rudder only turns. Hovering in all orientations with the odd piro and pitch pumps thrown in. Simple but very enjoyable, and exiliarating with his bird.
I can't wait to get her back in the air.

 

[Tomhintz]

I have ordered the black torque tube gears as my replacements.
It seems the front set of gears are the ones that take the greater forces when the tail rotor hits. At least they are inexpensive and are easy to replace. The problem with reinforcing a weak point is that the damage will just be displaced to another part of the train. I do agree though that the white gears strip a little too readily. This seems to be common with all torque tube drives.
Thanks for the suggestions Tony. I have decided the training gear will go back on while I play around with settings.
I shall order the parts this week as I am off work Friday and hope to start rebuilding then.

Sounds like its all going well Tom. I had just got to the stage with mine where I was enjoying some easy FFF just going from left to right about 50 feet out either side from me with simple rudder only turns. Hovering in all orientations with the odd piro and pitch pumps thrown in. Simple but very enjoyable, and exiliarating with his bird.
I can't wait to get her back in the air.

I also am making progress. i am getting ready to head out to the field again for an extended session today I hope. I just need to get some time on the helo doing simple things until I get more natural on the sticks. I remember the progressions with planes, tough, tough and then all of a sudden it all made sensse and the learning took off on a much faster pace. It will get there, especially since I have sort of promised myself a tRex 500 when I do. but first I just ordered a hot new plane also....gets here Tuesday so I will have a marathon building sessions to get that in the air also. But I can take breaks and hover around the yard, something I really like about the TRex 450. Fly at home, I love it.

 

[Tony]

Ah yes, 500 skids will work, you will just have to drill new holes. Derek (mountaindewdude) has 600 skids on his 500 for stability and to get that tail up.

As for the gears, I would check that mesh really close. The black ones can literally dig a hole in the ground and not strip if they are set correctly. If you have not watched it yet, check out my "How to Properly Built A Clone" video. I show how I set the gear mesh on the tail in that video.

 

[Tomhintz]

Another great day with the Trex 450. 9 flights, no tip overs. One of the guys had a 15-tooth pinion so I put that in, left the throttle settings alone in the radio aznd the extra head speed made it even more stable in the gusty winds. I still have to fly it for sure but it's not dropping so bad now. when it staerts to come down a click or two of throttle conrols it. Everybody there (the heli guys) thought it was slow on headspeed at first and it looks like that was right. I am getting a tach tnhis week so I can actually see what is going on.
Lots of fun with it, I am liking this helo!

 

[Tomhintz]

I just wanted to post an update. Since installing the BeastX and a new set of tail drive gears to get rid of a fading tick, I have been flying the Trex 450 Pro all but constantly ever since. Every day I have been putting in a dozen or so flights in the yard and this thing simply hums along with no issues. I have been getting worried that things might be wearing out so have been looking it over but I can;t find anything that is loosening up or changing in any way. I give it a shot of bearing oil now and then and fly.
I also got my fancy tachometer and at full spool up (still on the ground) I am getting a consistent 3200 rpm at the rotorhead. It seems to fly very well this way so I have left it right there. This is with the 15 tooth pinion and 150 tooth main gear, at 80% throttle.
Ever since installing the BeastX I have been flying it in idle up and so far have not had any issues with the collective. It does seem easier to maintain an altitude but I am being a bit restrained in what I do in the air. I am in no rush to get inverted or anything. Just hovering aorund and landing where and when I want is still fun so I will collect all of the practice I can before i get stupid on the sticks. see the lin below for my review of this helicopter.

Align T-Rex 450 Pro - Fighting My Alzheimer's

Thanks for all the help!

 

[Tony]

Hey Tom, sounds like you are getting along great with that little heli! The beastX is a great gyro, I have it on my 600N as I'm sure you have read and love it. On my 450's, I keep the 3GX, but it's more for testing than anything. But the BX is just solid no matter what.

Keep up the good work. One question. Is there any way I can get a link back on your website? I love what you are doing and how you are doing it, and I love helping people. The more link backs that I can get, the more people we can help on here. I would greatly appreciate it if you can do it. Keep it up bro!