RC Groups

RC Groups
    Beginner Training Area (Heli-Electric)
        Discussion HK450 does this sound right? (motor sounds strange)

#1 Glasswalker Jul 07, 2009 10:21 PM

HK450 does this sound right? (motor sounds strange)
 
Hey, so my radio arrived. I have hooked it up and followed Jasmine's instructions on setting up the DX6i. Went well, all servos appear to be working right, everything appears to be in the right place.

Then I programmed the ESC according to instructions. Only thing that was odd is that I found it wouldn't program at all unless the motor was connected. If motor was disconnected got no tones at all from the ESC, but with motor connected it played the tune as expected.

Anyway, when done, I accidentally spun up the motor (because motor was connected) nothing was near heli so it was all good, just surprised the hell out of me lol

Anyway, when it did, it sounded odd. Like a gear skipping or rubbing funny... Not sure what's making the noise, so I recorded it to post here.

Also main gear has a bit of a wobble. But doesn't appear to be rubbing anywhere I can see. No binding anywhere I can tell. at least as far as main gear to tail gear, and in tail belt and so on. So I think it might be between the main gear and the pinion.

By the way. The highest this got is about 5% on the stick from the bottom of throttle. (after throttle curves set as per Jasmine's instructions, and in normal mode, not idle up)

Please let me know your thoughts and any suggestions.

Here's the vid:

First spin up of motor on HK450 (0 min 22 sec)

#2 grnbrg Jul 07, 2009 10:47 PM

The ESC doesn't make any noise -- the beeps are made by the motor. If it's disconnected, no noise.

As for the strange noise, I'd suspect the wobbly main gear. Does the main gear ride up into the shoulder of the pinion at all?


grnbrg.

#3 igotit Jul 07, 2009 10:51 PM

sounds like your gear mesh is too tight...loosen the motor put a strip of paper between the gears then re-mesh and tighten the motor....roll the paper out and the mesh should be set!

but im leaning towards this one
it could be the set screw in your pinion hitting the gear too,are there any marks....like every 3/4 in on your main gear?

may have a dented tooth on the pinion too!

#4 Glasswalker Jul 07, 2009 10:57 PM

lol wierd. The manual from the ESC says to connect ESC but not the motor, then power up with throttle on full, then it will play a tune. I ended up having to do exactly that (but with the motor connected). Interesting didn't know it was the motor that played the tune.

I manually spun the motor by hand and went through a couple revolutions of the main gear. It wobbles but only about a mm or so in each direction, it never touches anything I can see, and never rides off the main portion of the pinion at all.

I did notice when looking up close there appears to be small fibres of plastic dust on the pinion and near it on the chasis and such after that short spin up... Is it possible my pinion is eating up the main gear?

It's a 12T pinion from LHS. I brought the heli/motor into them and they found one that fit the shaft of my 2836 Turnigy motor. I have the motor pushed up against the main gear as tight as I can get it. and locked into place. It appears to be meshing ok.

This noise just has me a bit spooked, don't want to trash the main gear or have it shake itself apart lol...

Any further suggestions? Anything I can photograph or videotape closer up to give you more information?

Thanks!

#5 arbilab Jul 07, 2009 10:57 PM

Yep, the music comes from the motor coils. Even harddrives do that. You can hear a motor sing before it ever moves. DO pay attention to what things sound like, they can tell you a lot.

My puter is a dinosaur, can't play linked videos. All these plastic gears have radial and axial runout. How much is too much is subjective. Some of it will disappear with runtime, as the parts machine themselves into compliance.

#6 Glasswalker Jul 07, 2009 11:03 PM

Quote:

Originally Posted by igotit
sounds like your gear mesh is too tight...loosen the motor put a strip of paper between the gears then re-mesh and tighten the motor....roll the paper out and the mesh should be set!

but im leaning towards this one
it could be the set screw in your pinion hitting the gear too,are there any marks....like every 3/4 in on your main gear?

may have a dented tooth on the pinion too!

Oh! I never thought of TOO tight lol... yeah I pushed the motor up as tight as it would go. probably my mistake right there. I'll loosen it off and re-adjust with paper as you suggest. (I tightened it because I thought it was too loose, if I held the head still, and turned the motor by hand it skipped gears fairly easily so I thought it was too loose, so I tightened it a bit. but I guess I over did it lol).

I checked if the set screw was hitting it doesn't appear to be. it has at least 1mm or more of clearance from main gear at all points in rotation. Also no marks on main gear all the way around (just little fibers of plastic dust from the main gear getting chewed up).

I'll try loosening it off tomorrow and re-adjusting tomorrow and see what that does.

In the meantime if anyone else has any more suggestions let me know :)

Thanks!

#7 igotit Jul 07, 2009 11:04 PM

Quote:

Originally Posted by Glasswalker
lol wierd. The manual from the ESC says to connect ESC but not the motor, then power up with throttle on full, then it will play a tune. I ended up having to do exactly that (but with the motor connected). Interesting didn't know it was the motor that played the tune.

I manually spun the motor by hand and went through a couple revolutions of the main gear. It wobbles but only about a mm or so in each direction, it never touches anything I can see, and never rides off the main portion of the pinion at all.

I did notice when looking up close there appears to be small fibres of plastic dust on the pinion and near it on the chasis and such after that short spin up... Is it possible my pinion is eating up the main gear?

It's a 12T pinion from LHS. I brought the heli/motor into them and they found one that fit the shaft of my 2836 Turnigy motor. I have the motor pushed up against the main gear as tight as I can get it. and locked into place. It appears to be meshing ok.

This noise just has me a bit spooked, don't want to trash the main gear or have it shake itself apart lol...

Any further suggestions? Anything I can photograph or videotape closer up to give you more information?

Thanks!

is the pinion the same pitch as your main gear?(example) if the pinion is a metric pitch and the spur is a standard pitch,the pinion will not seat all the way in the spur gear and will eventualy eat all the teeth on the spur gear!
i had this problem on a tamiya rc truck....seems tamiya for some ungodly reason used hard to find metric pitch gears.when id mesh the standard 64 pitch pinion against the metric tamiya spur it looked like a match,but when everything was tightened down....out came the noise and plastic shavings!

#8 jasmine2501 Jul 07, 2009 11:43 PM

Yeah it sounds wicked tight to me :)

Find the tightest spot on the gear, and run some paper in there, and push the pinion into the paper. It also sounds like you have the brake activated, but it could just be that it's too tight.

My buddy's HK450 sounds pretty good - almost as smooth as my Trex.
Dave's HK450 (9 min 32 sec)

#9 Glasswalker Jul 08, 2009 07:10 AM

The pinion from LHS was RRP 1112 48P Metric 12T. It was the only one that fit the motor shaft, all the rest were too small to fit on the 2836 motor shaft.

What is the pitch of the main gear in the HK450? Is that my problem? and if so then I'm kinda screwed for the next couple weeks as I have to order a pinion from somewhere else to get one that fits my motor.

(that's very odd because the LHS carries align parts, but we tried like 5 different 11T, 12T and 13T pinnions, and none fit the shaft, only this one would fit the shaft)

I'm going to try loosening it off and see if that helps.

Thanks!

#10 Glasswalker Jul 08, 2009 07:25 AM

3 Attachment(s)
Ok I just tried loosening it. But I could only back it out about a quarter of a mm. I didn't realize it was already basically at the extent that the motor mounting holes would allow.

I tried feeding a piece of paper in, and it fed into the gear mesh fine. But with the paper in there I can't budge the motor from the position it's in. (and it is crimping the paper into zigzag patterns with the motor screws completely loose, motor sitting at the farthest extent from the main gear)

I've attached some photos of the gear before I loosened it off you might have to look at the fullsize photos to see what I mean

#11 Glasswalker Jul 08, 2009 07:43 AM

Ok I did some digging, and found this ebay listing for trex 450 pinions. These say they are 48Pitch as well. with 3.17mm shaft diameter. Which is the same as what I got from LHS.

http://cgi.ebay.ca/3.17-mm-shaft-mot...lenotsupported

Anyone here more knowledgable about pinion gear pitch? If I can confirm for sure I have the right pinion, then I will just keep puttering with adjusting it, but if I definately have the wrong pinion gear I can hit LHS on the way home from work tonight and see what they have to say.

Thanks!

#12 Glasswalker Jul 08, 2009 07:55 AM

Ok, to further confuse things. The package from the pinion is labeled RRP 1112 48P Metric 12T on the front, but on the back there is a barcode with small print below which reads "1112 Pinion 12t 32 pitch metric (.6mod)""

Umm conflicting information much?

#13 grnbrg Jul 08, 2009 09:15 AM

Quote:

Originally Posted by Glasswalker
Ok, to further confuse things. The package from the pinion is labeled RRP 1112 48P Metric 12T on the front, but on the back there is a barcode with small print below which reads "1112 Pinion 12t 32 pitch metric (.6mod)""

Umm conflicting information much?

You may well have found the problem. I'm pretty sure most 450 class pinions are 0.5 mod (whatever that is... ;) ) and if yours doesn't match, it's going to cause problems.

And you're seeing white plastic shavings near the pinion. Which meshes with a white main gear....


grnbrg.

#14 flypaper 2 Jul 08, 2009 10:31 AM

Glasswalker: You do have the right gear as I've been using the same one for quite a while. Try this. Turn the big gear around till you find the tightest spot where it meshes with the pinion. and put a mark on it with a magic marker. Now you know where the tight spot is even with the gear loose. Now loosen the pinion gear and back it off a bit then just snug it. Hang on to the big crown gear and rock the motor housing back and forth to feel the gear mesh. Slide the gears closer together till you can barely feel the play in the gears then tighten the motor up and give it a go.May take a few tries to get it right. After you run a few batts through it, check the gears again, lining up the magic marker mark, as they will loosen up a bit as they wear in. Hope this helps.

Gord.

#15 Glasswalker Jul 08, 2009 10:39 AM

flypaper: ok so your saying your using the exact same gear as I am? Is it 48Pitch or is it 32Pitch? since the packaging lists it as both lol... Grnbrg seems to think I might have the wrong gear.

When you say your using the exact same gear, you mean the exact same make/model that i have? or do you mean your also using a 48P Metric gear (of some other brand).

Just want to be sure. I don't want to chew up my entire main gear, seeing as HK is out of stock, and who knows how long it would be to get a replacement. (although I could grab an align one from LHS likely but they would likely charge me $20 at least for it if not more lol)

Thanks!


All times are GMT -5. The time now is 01:55 AM.