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130X Blade 130X Helicopters Information and Help


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Old 07-10-2012, 04:35 AM   #1
poor_red_neck
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Default [VIDEO] Is this the cause of the umbrella "A" gear issues?

So no word yet from HH, and I figure this is just going to be something that we're going to have to figure out ourselves.

First, sorry for the long video. I have a habit of repeating myself and going on tangents.

It's too much to describe and try to put into text, so I made a video. I make a few mistakes, but please watch until the end as I clarify a few things, and correct the mistakes (I hope).

Tell me what you think.

Please fullscreen in HD and so the annotations show up throughout the video. This is my first TT, so I keep getting the name of the gears wrong.

[ame]http://www.youtube.com/watch?v=n9L1Ip56wFM[/ame]
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Old 07-10-2012, 05:43 AM   #2
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Great video and I appreciate all your hard work and effort. What if you made a thin shim to fit outside on your tail boom and push your tail servo flush against it?

Bob
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Old 07-10-2012, 06:26 AM   #3
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Interesting video. I do not have a 130X (yet) but have been reading about all the problems with gear wear and have seen several suggested causes and fixes.

It seems to me that letting the B and C gears slide on the TT means that their position on the TT should be controlled by the front and rear TT bearings. If that is the case it should not matter whether the tail boom and tail case are pushed fully in or not, within reason, as long as flats are long enough.

However, as you suggest, if the flats on the TT are not long enough then one or both gears will be pushed further towards the front or back than intended as they will not be able to ride on the bearings because they cannot slide far enough onto the TT. If that is the case then it would be better to have the tail boom not pushed fully home into the frame or tail case, which agrees with your conclusion.

Incidentally, I believe that the flats are not of equal length. Has anyone tried extending the flats to allow the gears to take up a position controlled by the bearings ?
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Old 07-10-2012, 06:57 AM   #4
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I was also wondering, what if you took a dremel (with a large barrell sander) and removed about .5 mm from the rear of the B gear......this would alow the boom to sit all the way in and would give the play you need to mate the A & B gear?
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Old 07-10-2012, 07:18 AM   #5
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Hey PLR, thanks for the work on the vid.

A couple of notes just from me for what I've found as I did quite a lot with replacing the A gear with the metal one last night and I'll kind go a long with the time with you vid.

For sure I don't think you want to push the boom all the way in for an adjustment for the backlash. Would say this for both the plastic gear as well as the metal one.

In looking at your vid with the metal one, I can even see the shinier part of the lower edge of the new metal A gear so for sure, all the way in is making contact.

One other thing to note on this too is that essentially, as you kind have I think figured out, for end to end play, the TT rod stops at each end are really the only thing that both the B & C gears are pushing against.

In other words, as you push the boom forward, and then have the B gear come up more from this, what all that is coming from really is since the tail moves with that, essentially the D gear pushes on the edge of the C gear, this then puts pressure from the C gear and pushes on the rod on the tail side stop, this then pushes the rod forward which because it has the cut stop at the B gear end, then pushes on the B gear and moves this forward.

So not only are you moving the B gear too much forward and can have issued with that as you have seen, if it is pretty snug and there is any preload on things, that load is being transmitted to everything of all the gears. And a especially weak spot would be the C gears D cut hole as for sure that gear being plastic, I'm sure will not hold against that pressure for very long. Then also too, consider the increased impact loads in a hard crash that you could get from transmission even if everything is tight, and or as well with so many parts being plastic, what you get from them flexing during that.

Also keep in mind that running angled gears like these are, also have a tendency to repel each other if you get what I mean and will increase that load as they are run and especially at high speeds.

All in all, when I was putting mine together for which I split the frame so I was seeing where the boom stopped, I could see that all the way was too much and even just for the sake of curiosity, I pushed it to what I saw was the frame boom stop and spun it a little and could tell the edge of the B gear was jammed into edge of the A gear like you are showing.

So yeah, at least on mine, and from the looks of it, on yours, all the way in is too much.

Essentially I think while it means its a variable and needs to be set right if you mess with this, still... I don't think it matters if the boom is set a little back in the frame or not. Might have even been intentionally designed this way? As well while I don't how this has been for you, but the clamping pressure of the frame on the boom is pretty darn good too so I don't think it will have issues moving once you set it (?). On mine I even also found what looks like a little strip of white tape on just the Port side flat of the boom which probably also is what helping to keep it tight.

Will say it might be something to keep in mind to check though if you have a bad crash that would have jammed that forward.

Also I think to keep in mind is that there actually could be a need for some room for expansion as the TT parts run and get hot. You many not think this is a thing, but for my 450 Pro and 700, (and yeah much bigger stuff I know) but in sitting in the cool of the house with the A/C, there is a bit of a loose backlash with the TT gears, but then take them out on a hot day and check that after they just came in from a flight and there is a noticeable change to them being more tight.

All in all, I think (?) with the metal A gear there is going to be less of a concern of the backlash having to be very snug. Hopefully with the gear being so strong being metal we can leave enough room for things not to bind and or have any more pressure then needed and not have any issues.

That's the way I set mine up and it does have some lateral movement in it kind of just like yours did in the end and while I have only one flight on it, it seems to be really really good.

One last note as you did mention it in the vid that you hadn't split your frame yet is that while I kinda already said this, for sure there is not a direct connection at the body side of the boom between the tip of the Boom, the Bearing and the rear face side of the B gear.

Kinda thought there was before I split mine too, but if you do you will see that the frame has a stop for the boom then a round slot for the bearing, then the other side of the bearing slot has a similar stop (really might say both stops are really more to keep the bearing in place) then there is a good gap between that and the base of the B gear which is being held that way by the cut stop in the TT rod.

Essentially unless you pull that boom way out, I couldn't image the B gear touching the bearing face at all.

Also it is my suggestion that you don't try to cut the slot more so the boom can be all the way in but the gear can go back further but just slip the boom out a little more like you have. For me also not only did I do this but then I moved the tail servo right against the frame and adjusted my tail link ball out to compensate. Figured while the frame is holding it pretty good, the clamp if the tail servo should really doubly make sure the boom doesn't move in and also will be a easy thing to look at if it slips out.

As you did ask, at this point my helo is all back together so I can't take any pics but really to see all of this better I would suggest you split the frame. Probably will end up doing it some day anyway and its really not that much of a big deal and probably will show you a lot more to see just what you are wondering about then any pics anyway.

Hope those points were of some help.
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Old 07-10-2012, 08:13 AM   #6
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Two things I did to mine greatly reduced "gear lash".

1) I loctited the B gear to the the TT. This is where the vast majority of the "lash". I put that in quotes because it isn't actually gear lash, it's the lash between the gear and the TT. IMO the benefits of having the B gear float are way less than having that gear stay in one spot in relation to the A gear (more on that in a sec), as well as reducing "lash". As the torque load on the TR changes, the TT rotationally bangs back and forth inside the B gear, and since both are metal, all the damaging forces end up on the A gear. This is the first TT setup I've had that does not have solid mounted gears on both ends of the TT.

2) I changed out the TT bearings. The stock bearings have a fair amount of play between the outer and inner race. In the 130x, the A gear keeps the B gear from flopping up (and on mine was holding it down), so the slop showed up in a side to side movement of the B gear when you hold the main gear and fiddle with the tail rotor. Not good. Changing out the bearings seems to have decreased that side to side play a bunch.

A local buddy also has a 130 without these mods, and his total resultant lash is something like 60-70 degrees at the tail rotor (hold the main gear so it doesn't move and see how much the tail rotor moves from lock to lock). After doing the above two mods, mine is down to 15-20 degrees. I'm waiting on a set of flange bearings to get the TR output shaft tightened up, and I know that'll reduce the play more, and make the tail even more solid than it is now.

I did have to custom fit the replacement A gear as well. There was some flashing on the top side that put the A-B gear mesh in a bind. Also, the OD on the A gear as rubbing the elevator servo fet. I too a couple .01mm's off using a lathe and it does not adversely affect the A-B gear mating.

A tight heli flies better is all I'm saying. Having the B gear slip fit on the TT is nice for replacing things without disassembling the frame, but it's also a source for sloppiness. The bearings as well, and Blade's choice of bearings could be better.
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Old 07-10-2012, 08:42 AM   #7
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Great video poor_red_neck. . Last nite I change out my A gear becuz I was getting a tiny wag after 25 flights my gear was more worn on the inside and outside. I didn't catch if my gear was touching (I will check my earlier pics). But if you take a look at this first pic my drive shaft is near the edge of the B gear and in the C gear the shaft is sticking out so I red loc on it. In the next pics you see that I have clearest on the A gear and B gear lol I think I did that by mistake to get the clearest that I have thank you Jesus. Also you see that the B gear is sitting inside the frame. I didn't even have to move my boom . Oh before I forget the ring that is around the A gear is where I sanded (800 grit) it down to keep it from touching the mofet on the servo. Here are the pics. PS I checked earlier pics and it do look like the B gear round part was touching the A gear.

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Old 07-10-2012, 08:44 AM   #8
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Ok while I love the product.. I can't help but say what a horrible design they used for this. I really wonder if they had spent the money to make it belt driven would it have been a better concept. even if it was 299.99 or something.

I mean, even in a repair if you do not have keen eyesight you are in trouble. Good video good topics.

I hope HH sees this and they wonder what they can do to adjust this for the next version.

I am not a engineer, I am a IT Director but I can tell you that sadly that is "game breaking" as a main part of the heli.

Mine is doing well so I don't want to jinx it but yeah, if it acts up I will send it in.

Good job though.
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Old 07-10-2012, 08:53 AM   #9
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Quote:
Originally Posted by tntburnett View Post
Great video poor_red_neck. . Last nite I change out my A gear becuz I was getting a tiny wag after 25 flights my gear was more worn on the inside and outside. I didn't catch if my gear was touching (I will check my earlier pics). But if you take a look at this first pic my drive shaft is near the edge of the B gear and in the C gear the shaft is sticking out so I red loc on it. In the next pics you see that I have clearest on the A gear and B gear lol I think I did that by mistake to get the clearest that I have thank you Jesus. Also you see that the B gear is sitting inside the frame. I didn't even have to move my boom . Oh before I forget the ring that is around the A gear is where I sanded (800 grit) it down to keep it from touching the mofet on the servo. Here are the pics. PS I checked earlier pics and it do look like the B gear round part was touching the A gear.

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Wow in that second pic, your rod seems to have come way out past the face of the C gear.

A thing to note is that the stop of the D cut for the rear gear on the TT rod is shorter then the front.

Essentially its really made so that normally, it should just fit to the face of the C gear.

So to see it that far would almost make me wonder how that is where it is unless it has been pushed out past the D cut section of the rod.

In saying this I am leading to that I have herd that some of them have been coming with the rods in backwards.

So if it is, while I haven't tried this myself, if your rod is going that far back but still has not rounded out the D cut in the C gear, you very well might have the rod in backwards. Which also means, especially if the rod has slipped back this far, that you may barely have much of the front of the rod in the B gear.

Its up to you but if things are like I am talking about there the C gear is not rounded out, you might want to pull things apart and check on this.
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Old 07-10-2012, 09:46 AM   #10
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Quote:
Originally Posted by WBFAir View Post
Wow in that second pic, your rod seems to have come way out past the face of the C gear.

A thing to note is that the stop of the D cut for the rear gear on the TT rod is shorter then the front.

Essentially its really made so that normally, it should just fit to the face of the C gear.

So to see it that far would almost make me wonder how that is where it is unless it has been pushed out past the D cut section of the rod.

In saying this I am leading to that I have herd that some of them have been coming with the rods in backwards.

So if it is, while I haven't tried this myself, if your rod is going that far back but still has not rounded out the D cut in the C gear, you very well might have the rod in backwards. Which also means, especially if the rod has slipped back this far, that you may barely have much of the front of the rod in the B gear.

Its up to you but if things are like I am talking about there the C gear is not rounded out, you might want to pull things apart and check on this.
Point taken, I have done that too. from factory it was like this so I flipped it around and its the samething still sticking out of the B gear. Notice the pic with with the B gear it is sitting at the edge if you would flipp it then out of the B gear than cause the shaft to slide back forth while flying . I have flown it and no issues. I may just do like poor_red_neck said just sand down one end of the shaft.

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Old 07-10-2012, 09:47 AM   #11
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poor_red_neck- great video, and I think you have demonstrated very well the proper way to check the clearance/fit of the A/B gear. This clearly shows that the original "push the boom all the way in" suggestion is not what folks should do. I think due to the manufacturing tolerances, it's more prudent to adjust boom fitment and gauge gear fitment as you have shown.

Great job... great clarity in the video, and good suggestions. THANKS!
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Old 07-10-2012, 09:49 AM   #12
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what you just verbally explained. Sounds like it would cause binding. IF too tight.
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Old 07-10-2012, 09:53 AM   #13
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Yes, I can see where the TT is rubbing on the D gear spindle.

Bob
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Old 07-10-2012, 01:42 PM   #14
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Poor red neck I think your TT either doesn't have the flat spot cut far enough back, or your boom was cut a little too short.

There is a positive stop in the frame for the boom to sit against, and there is a bearing hold too.

What is causing your gear to bind when the boom is fully inserted is the D gear pushing on the C gear.

If the flat spot on the TT was cut back a little further or your boom was a little longer this wouldn't be an issue.

Rather than grinding the flat spot back on your TT, I would suggest simply adjusting the boom like you did in the video, and then like some one else mentioned, have the servo mount flush against the frame to help hold it in place.

One more option might be that the C gear isn't pushed all the up to the end of the flat, You mentioned you used some glue on the shaft, did you push the C gear all the way up to the end of the flat?
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Old 07-10-2012, 03:11 PM   #15
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Quote:
Originally Posted by Iskareot View Post
Ok while I love the product.. I can't help but say what a horrible design they used for this. .
Hell yes, this is ridiculous. Why no set screw on the B gear? It's guaranteed to move back and forth affecting the mesh between A and B and stripping A gear. I don't get it really.
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Old 07-10-2012, 03:25 PM   #16
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Quote:
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Poor red neck I think your TT either doesn't have the flat spot cut far enough back, or your boom was cut a little too short.

There is a positive stop in the frame for the boom to sit against, and there is a bearing hold too.

What is causing your gear to bind when the boom is fully inserted is the D gear pushing on the C gear.

If the flat spot on the TT was cut back a little further or your boom was a little longer this wouldn't be an issue.

Rather than grinding the flat spot back on your TT, I would suggest simply adjusting the boom like you did in the video, and then like some one else mentioned, have the servo mount flush against the frame to help hold it in place.

One more option might be that the C gear isn't pushed all the up to the end of the flat, You mentioned you used some glue on the shaft, did you push the C gear all the way up to the end of the flat?



The flat on the TT shaft near the B gear is one of my thoughts, mentioned it at the end of the video.

The C gear is pressed all the way on the TT. The flat spot seems to be ground correctly on that. I have had 0 issues with the TT riding forward, like some have. I put the CA on there as a precaution. The interference fit is tight "enough" on mine, but again I did it as a precaution. I put a very small amount on the gear/shaft, pressed it on all the way, and cleaned all the excess. The TT shaft is flush with the end of the C gear, which appears to be how it's supposed to be.

Thank you for bringing up the stop in the torque tube. I haven't split my frames apart yet so i didn't know if the torque shaft bearing mates with the tail boom or not.

So I guess I'm betting on the flat of the TT not being ground fully on the B gear. Seems like the most logical explanation, and probably the easiest thing to get screwed up on an assembly line.
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Old 07-10-2012, 03:30 PM   #17
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Quote:
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Hell yes, this is ridiculous. Why no set screw on the B gear? It's guaranteed to move back and forth affecting the mesh between A and B and stripping A gear. I don't get it really.

If I can find my shiny new micro metric tap set that I JUST BOUGHT a few weeks ago, I'm going to try this out. I've got plenty of set screws, and time

I really don't want to loctite the gear in there. I just see that causing all sorts of issues when I go to take it apart. Can't get heat to it to release it because of all the plastic.

Got 5 flights in today with the tiny bit of play on the gear. Umbrella gear is looking good!

My new pitch slider from HH is a little bit sticky though, and causing some fast tail wobbles (just a few degrees) under heavy collective. I've reset all gyro gains, then went -6 clicks of gain on the rudder. It has helped, but I'm starting to get minor blow outs in very fast backwards flight so the gain is just a band aid. It's most noticeable on tic tocs, and very fast forward flight, it will oscillate.

Guess I'm going to try and polish down the pitch slider peg just a tiny bit, as that's where it seems to be binding. Good news is the new pitch slider I have has a much better bearing in it than the one that came with it. Noticeably less slop.
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Old 07-10-2012, 03:40 PM   #18
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Quote:
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Guess I'm going to try and polish down the pitch slider peg just a tiny bit,
Wouldnt it be safer to open up the slot that the pin sits in? less likely to break anything that way.
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Old 07-10-2012, 03:47 PM   #19
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BTW, the tolerances between A and B sets and C and D sets seem to be huge. Normally, I'd expect the edges of umbrella gears to match to set the mesh correctly. On your video (thanks for this btw) and all the pictures theyseem to be way off - attached example from my proper heli.
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Old 07-10-2012, 04:42 PM   #20
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I agree completely. It is important for proper mesh for them to operate as designed.

I actually don't really have any issue with the rear tailcase gears. They are butter smooth for me. When I pulled my boom all the way out, I took the oppurtunity to feel the mesh by twisting the torque rod. It was very smooth, with no binding. Seems all my issues is between A & B gear.

I'm starting to think the best solution is going to be a set screw in the B gear. If I can't find my metric tap set, I'm just going to take it to my buddy's machine shop and have them drill and tap it. If you take out the servo that I have removed in the video, it would be quite easy to set the gear mesh, and tighten that grub screw.
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