Trouble with Neu again - RC-Monster Forums

**Trouble with Neu again -** 12.30.2008, 02:45 PM

wtf am I doing wrong?......just got my 1515/2.5d back from neu...they said they replaces the rotor....I put it in my crt x1 with MMM geared 48/16 running on six cells.....the shaft snaped in about 10 min is the rotor part of the shaft and what could be causing this?

jayjay283 · 12.30.2008, 03:39 PM

man bust you have been getting some bad luck, mesh too tight ? neu making too many motors and quality control going down hill, I dunno. Sorry for your loss again

BrianG · 12.30.2008, 04:00 PM

Do you have a pic of your setup? Aside from a QC issue, I would start looking really hard at the mount. Snapping a 5mm shaft isn't easy so I would say there is something up with the mount and it flexes when landing jumps or something.

suicideneil · 12.30.2008, 04:55 PM

Landing on throttle, hitting the throttle and brakes to hard, flexing motor mount- all things I would look at too. I would say the lack of a slipper could be to blame, but that would really only result in stripped gears rather than a broken shaft (twisting forces vs ...longitudinal ones? you know what I mean though).

12.30.2008, 05:48 PM

no jumps and landings this time guys....the ten minutes it ran was on grass....maybe that was the problem...too much traction?

running on crimefighters

will ger some pictures brian

sleebus.jones · 12.30.2008, 06:00 PM

I'd be inclined to look at a mount issue too. 5mm is beefy, and to snap it in 10 mins is surprising.

BrianG · 12.30.2008, 06:07 PM

If the mount is solid, I would then check the spur gear for true-ness. Some spurs have "high spots" and can cause a lot of stress on the motor/shaft. I assume that when you check the mesh, you check the entire spur?

E-Revonut · 12.30.2008, 07:34 PM

I agree that 5mm is a beefy shaft and hard to break! My tiny 1/8" shaft on my original Novak HV lasted many, many runs and withstood several standing back flips before finally giving out. I beleive the only reason it snapped was I had an original E-Maxx slipper setup on my G2R REVO and I actually melted everything throwing the spur out of whack and I believe that it what broke my shaft!

suicideneil · 12.30.2008, 08:56 PM

I had the original 3mm hvmaxx motor, and the upgraded sintered rotor with a 3mm shaft also, and a LOCKED 3906 spec slipper; never broke it no matter how harsh I was with the throttle, repeated backflips etc.

A picture of the broken neu shaft would be good, might be able to identify in which direction it appears to have broken/sheared.

emaxxnitro · 12.30.2008, 09:11 PM

yeah it would be better if neu used hardend shafts. my neu shaft can be ground down with a hand file and also the set screw leaves a mark on the shaft

12.31.2008, 01:01 AM

lol.....Neil just reminded me I forgot to post the pic

www.rgcbuilders.net/neu1.jpg

sleebus.jones · 12.31.2008, 09:21 AM

Quote:

Originally Posted by emaxxnitro

yeah it would be better if neu used hardend shafts. my neu shaft can be ground down with a hand file and also the set screw leaves a mark on the shaft

If it had a hardened shaft, the grub screw would never be able to get a bite on the shaft. Furthermore, if it was hardened, it would be more brittle, making failure more likely. If anything, the shaft needs to be more ductile.

suicideneil · 12.31.2008, 10:07 AM

Ouch, that shaft looks like it has broken flush with the bearing, or inside the motor even?

12.31.2008, 10:20 AM

Quote:

Originally Posted by suicideneil

Ouch, that shaft looks like it has broken flush with the bearing, or inside the motor even?

yes about 1/4" inside the motor....seems very strange to me

TexasSP · 12.31.2008, 10:48 AM

I don't know how the CRT is built but it could be something to do with the chassis and the way the center diff is mounted causing flex as well. Shocking to me to see a 5mm shaft break so quickly.