Graphic 430 motor bearing replacement

[Lzfalcon]

Originally Posted by MartinS819

IDK so correct me if I'm wrong, but wouldn't locktight just liquify from the heat the motor makes? Maybe CA instead? BTW what happens if you do touch the coils...with like a screw or something? Is there a way to fix it then?

Thanks,
~Marty

I have used solution 22 bearing retaining compound High strength, High temp (to 450 F) High viscosity
Made by MRO solutions. pricey stuff

[Gary JP4]

I pin both ends with two pins or screws like the video weither the ends press in or screw in.

[Scottlclem]

I love the homemade tools you made to get the motor apart. You have a nice rebuilt motor that Align intended you to throw away and buy another. Thanks for posting this.

[aballen]

Any of you guys mind "sharing" your tools? I would be happy to paypal shipping costs, and promise to return the tool.

My 450 has had the "vibes" for a while, but I haven't been flying it as mch with the 500 in the fleet... I finally got around to taking her apart, I need bearings for the ms bearing block, and the motor sound like there is sand in it when I spin it, it is also a little too notchy... I'm pretty sure the bearing are shot in there too.

Anyway I'm going to replace all the bearings, I'm less crash prone than I was... but with out replacing the motor bearings I'm not sure how much of an improvement I will see.

Please P.M. me if you can spare your tool for a week.

Thanks.

[crgonzalez08]

I was wondering what diference will make if i use a 11T to a 13T pinion set. Im new to this stuff. My guess is that with the 13T will have more RPM but I just wondering if we can hear from some one who knows. Thanks

[lotaloi]

where the bearing could be found? We are so impressed that u did changed the thing with ur home made tool but who sells the beraing?

[heli-on]

You can buy the bearings here: http://www.readyheli.com/KX850165A_4...kx850165ta.htm
or here:
http://www.infinity-hobby.com/main/p...oducts_id=1777

They come with a free motor attached. Time spent mucking around with parts is flying time wasted.

How much do you think Boca would charge for this set of bearings *if* you could find them? Spending $25 to save $25 is kind of frivalous, no?

If anyone wants my old motor, it's your's for cost of shipping. (It's a 430XL that needs bearings - maybe 400 flights on it).

[Ecklund1]

Here they are. $6.50/set. You can probably find them elsewhere, too.

http://www.bocabearings.com/main1.as...=3155&n=R2-5ZZ

If you're capable, it's worth spending $50.00 on something else...

[Gary JP4]

From page 1

Originally Posted by Gary JP4

..............
for those looking for bearings if you have a hard time finding them as RZ-522, ... they are a non metric, or standard, 1/8 x 5/16 x 5/32" (0.125 x 0.3125 x 0.156"), which if you just have to spec them in metric is 7.93 x 3.17 x 3.57mm

You should be able to get them at any bearing supply or from Boca.

If you have the time you don't have to take the throw away mentality. These are good motors and it is worth replacing the bearings. I would replace the bearings even if I did get another motor just to have a spare.

[Turbojoe]

Hard to believe they used standard bearings in a metric motor. I've got tons of bearings here but nothing to fit my noisy 420LF motor. I already have it apart. Was no big deal. I'll glue it and pin it when I put it back together. I ordered bearings from Boca. Picked up a few others that I needed too so I ended up with free shipping. I LOVE that!

I know the 420LF seems like a waste to fix but it's going into a plank. Not a heli.

Joe

[Pompano Mike]

[quote=Pinecone;479406]Pulling my motor apart I would a washer inside. This was what locked it up. I think I may have dropped it in during the build. If so I got something like 60 or so flights before it locked up. /quote]

Did the exact same thing ten minutes ago while pulling my motor. That little washer under the motor mounting bolts drops down real nice inside the openings on top of the 430.

Handy little tip this.

Thank you, thank you.

[lotaloi]

Thanks the forum editor,
Thanks for making it as a sticky. THis things would be helpful for someone who engage a little time to do some custom things as well as not to buy extreme espensive RC stuffs.

[ShuNut]

How can you tell if the bearings need changing ? My XL had nearly 1K flights on it but it seems ok to me by the sounds of it, but if it got bad over time i wouldn't necessarily noticed it, so how can i tell ?

Thx

[Gary JP4]

Originally Posted by ShuNut

How can you tell if the bearings need changing ? My XL had nearly 1K flights on it but it seems ok to me by the sounds of it, but if it got bad over time i wouldn't necessarily noticed it, so how can i tell ?

Thx

As with any bearing you have to side load the bearing and feel by hand. You have to at least take the motor out of the heli to check though. It my still be hard to inspect both bearings while they are still in the motor. If you side load the shaft by holding the pinion and loading at various angles including pushing and pulling while all the time turning by hand and feeling for roughness, grittiness, or any anomaly you can probably tell about both bearings. The problem is to get the lower bearing (bearing opposite end from the pinion) side loaded. The bearing closest to the pinion makes that hard to do while the bearings are still in the motor. Of course if you took the motor apart and inspected the bearings separately in this same manor it would be easier or more accurate. The good thing is the bearing closest to the pinion takes the most load and is probably the most likely to fail first. If it starts to fail replace them both.

Any perceivable bumps, roughness, grittiness, or anything but smooth as a babies butt, arse, ass or glass is bad and should be considered as failure. Even one little spot an a ball is failure. Failure can be in the form of wear from overload or lack of lubrication like galling , spalling, brinelling, false brinelling, or just plain corrosion as in pitting (rust) usually from long periods of sitting and exposure with lack of lubrication for corrosion protection and or water or other corrosive in the bearing. You can feel all of those with your fingers while turning and side loading. With bigger bearings that are exposed (no grease seal) you can visually inspect them. With these little ones you can feel them.

I have been flying an SE since early 2006 and havent replaced a motor bearing. I did take the motor apart once to pin the end caps into the case so it wouldn't fall apart but didn't replace bearings. I have replaced all the others. With 1000 flight on them I would keep some on hand and put them in when you have the heli down for any kind of rebuild. Inspect the ones you are putting in to assure you don't replace old good bearings with new bad ones.

[toolguy420]

Originally Posted by Gary JP4

As with any bearing you have to side load the bearing and feel by hand.

Any radial bearing, that is. Great thread!!! Had one that needed new bearings - now I know. Thanks for the info!!! BTW, red or green loctite should work fine for putting the ends back on.

[Gary JP4]

Imagine the red dot on the ball is a bad spot. What would you have to do to get it to engage one of the races? That is when you would feel it as a bad spot.

Reference Wikipedia http://en.wikipedia.org/wiki/Ball_bearing



Of course there are some types of bearing side loading wouldn't apply to in checking for notcheness like maybe fluid bearings in a hard drive or a bushing perhaps. It does apply to some extent to axial (thrust bearings) except you take up any end play and also side load if possible.

Any bearing that can be disassembled easily, such as tapered roller bearings in a wheel bearing application, could be disassembled and inspected visually or any bearing big enough and open enough (unsealed) to see the bearings and races could be inspected visually while being checked tactiley.

[Pompano Mike]

Excellent graphic. Very astute. Kudos.

Granted I am a rank amateur at this sport, but in my mechanical experience, I'd replace bearings on a pm time line. In this case X number of hours flying time, given the cost of bearings vs.cost of repair due to failure. Basic risk/reward ratio. Most bearing manufacture's will give you mean time before failure.

But that's just me.

[Gary JP4]

Originally Posted by Pompano Mike

Excellent graphic. Very astute. Kudos.

Granted I am a rank amateur at this sport, but in my mechanical experience, I'd replace bearings on a pm time line. In this case X number of hours flying time, given the cost of bearings vs.cost of repair due to failure. Basic risk/reward ratio. Most bearing manufacturers will give you mean time before failure.

But that's just me.

I think I agree with you in this case. But, the motor is probably the only place were this would be beneficial on the heli as most folks like me, and apparently you based on your signature line, have most bearings fail from crashing. The motor bearings usually don't get the crash damage though.

I think with the bearings readily available to us and those competitive to that price there is more of a problem just getting good bearings to start with. I have had about a dozen that were bad right out of the box and read about a lot more like that. Many don't have round balls in them so checking for roughness is a habit for me now.

In 40 some odd years taking things apart and replacing hundreds if not thousands of bearings, I have never seen a bad bearing right out of the box until I came across Chinese (if you will) helis including the Trex. I have been (am) an aircraft mechanic having worked on and rebuilt piston, turbine, and home built aircraft, also professional and home lawn equipment, cars (foreign and domestic). I have raced rebuilt, and maintained motorcycles (foreign and domestic), go-carts worked on bicycles, skate boards, roller skates, machine equipment, boats, factory shop tools, and even model airplane engines. I have worked in building maintenance and all the equipment that goes along with that (HVAC, fans, blowers, pumps, appliances, etc), etc, etc. In all that I have replaced hundreds if not thousands of bearings due to failures or as a precaution but never had a bad one out of the box.

Still, I am happy with the price to quality relationship on these. I just check bearings before installation, after installation, after crashing, and periodically while in use.

[Pompano Mike]

Gary, your credentials speak for themselves. How about Boca Bearing? Are they US products or imports? Ceramic or steel?

No experience with these tiny guys and curious.

[Gary JP4]

Hi Mike,

I am not trying to brag. Just saying that I have seen a lot of bearings and they have all been good in contrast to the Align supplied bearings which contain some junk mixed in with good bearings. But, they work fine once you weed out the bad ones doing the inspection the Mfg. should have done. The remaining "good" bearings seem to be fine as far as tolerances and everything else goes. I am surprised at how well most of them are made given that some are so bad. It is like they make good bearings with precision ground tolerances but occasionally you get one that gets assembled and makes it all the way through production to packaging with balls in it that looks like raw unmachined iron ore. The rest are finished beautifully, work great and last a long time. Hard to conceive how that happens.

The Boca's are top notch. I don't know where they come from. Some of the imports are very good bearings. The Japanese like NSK are first class in my experience on bigger stuff. I here the Chinese can make good bearings as well but I have low confidence in their quality control. As I say, I use the cheap bearings on the airframe but the Boca's are probably worth it for the motor. They have both Ceramic and steel in general. I am not sure what they have for the motor. I don't really think you need Ceramic here but if you want it then the motor and the tail shaft are probably the two most indicated locations, due to high RPM, with the motor being the least likely to receive impact damage. Ceramic is not as good at handling impact damage as you probably know.

I have had very good luck with the bearings that came in the motor.

RC Bearings may also have a good set for the motor.

I hope that helps.