Need help keeping motor from moving... - RC-Monster Forums

pumpkinfish · **Need help keeping motor from moving... -** 01.05.2009, 12:39 AM

Hi guys. I had major issues with my MBX6 conversion today. In two different heats, the motor moved away from the spur enough to not make contact and I had to abort the run. I managed to get one good run, then it moved during the warm up lap for the main and I had a DNF.

I am running a Medusa motor with Mike's Mugen mount. When I had my 777 with the RCPD mount, I never had a motor move. I have tried blue loctite on the screws and that didn't help much either. It is always my top screw working loose and then the motor pivots away. I am wondering if there is a screw with serrations or a lock washer I can get into the groove of Mike's mount. I actually liked the RCPD mount in that the whole face was flat and I could use different headed screws. It seems like Mike's is made for cap heads only.

Please help me as I want to finish a race!!!

E-Revonut · 01.05.2009, 12:45 AM

Use a star washer behind the head of the screw. With that you should never have an issue!

pumpkinfish · 01.05.2009, 01:07 AM

Quote:

Originally Posted by E-Revonut

Use a star washer behind the head of the screw. With that you should never have an issue!

Star washer? Never heard that term before.

George16 · 01.05.2009, 12:50 AM

If not, you can also use a lock washer in addition to blue loctite.

George16 · 01.05.2009, 01:11 AM

Star washer:
http://www.circlipindia.com/star-washer.html

Lock washer:

E-Revonut · 01.05.2009, 01:17 AM

Thanks for the examples George, lot easier than explaining

What's_nitro? · 01.05.2009, 01:48 AM

Are you using cap-had screws now?

Honestly, you are #1 that I have heard of with this problem. Maybe the threads in that particular hole are worn out(?). Try rotating the motor to the next set and see if you still have a problem. I do find it hard to believe threadlock didn't help. Did you let it cure before the run?

pumpkinfish · 01.05.2009, 10:11 AM

Yes I let it cure and I am using cap heads. I bought brand new screws just becuase it was a new build. The problem with the Medusa cans is the holes are closer together if I rotate the can and they will not line up. I could do that with a Neu, but not a Medusa.

I may have to go back to my Neu to see if that does the same thing. I tried this Medusa just to see how it compared to my Neu plus it was more efficient than the 1512/2D I was running.

01.06.2009, 05:39 PM

Quote:

Originally Posted by What's_nitro?

Are you using cap-had screws now?

Honestly, you are #1 that I have heard of with this problem. Maybe the threads in that particular hole are worn out(?). Try rotating the motor to the next set and see if you still have a problem. I do find it hard to believe threadlock didn't help. Did you let it cure before the run?

out of 10 medusas ive seen run, 9 of them had thread problems. the aluminum/taps they use are crap. i usually just tap them to a bigger size right away, i have 6/32's in the motor im running now, and they loosen up after a race, not to bad tho

What's_nitro? · 01.06.2009, 06:54 PM

Quote:

Originally Posted by big greg

out of 10 medusas ive seen run, 9 of them had thread problems. the aluminum/taps they use are crap. i usually just tap them to a bigger size right away, i have 6/32's in the motor im running now, and they loosen up after a race, not to bad tho

That's very interesting- that it could be a design flaw with the Medusa motors.

If so, I hope it's fixed soon because I have been looking into their motors.

pumpkinfish · 01.07.2009, 09:10 AM

Quote:

Originally Posted by big greg

out of 10 medusas ive seen run, 9 of them had thread problems. the aluminum/taps they use are crap. i usually just tap them to a bigger size right away, i have 6/32's in the motor im running now, and they loosen up after a race, not to bad tho

Shark413, I can't see your picture here at work, stupid filters

big greg, I had thought about tapping the hole to a bigger size, but then I would have to modify the RC-M mount. It seems like Mike made the mount for the smaller size and Neu motors, especially since there is a channel for the cap head to sit in and the screw slots are not the right diameter. I'd hate to hack up the mount for one motor. Maybe I will buy another mount to play around with.

George16 · 01.05.2009, 10:14 AM

I never had problems with my screws loosening. But for added insurance, I use lockwasher with blue loctite to ensure they don't loosen up.

BrianG · 01.05.2009, 10:51 AM

In the two 50mm Medusas I have, there are two sets of mounting holes; the typical 25mm spacing, and a set that are narrower-spaced.

What's_nitro? · 01.05.2009, 08:13 PM

Have you tried the RED threadlock???

Make sure the socket is in good shape on the screw or you might not get it out.

rchippie · 01.06.2009, 03:17 PM

Quote:

Originally Posted by What's_nitro?

Have you tried the RED threadlock???

Make sure the socket is in good shape on the screw or you might not get it out.

I would advice against using red locktite . It will stick very very well & make it tough if not impossible get the screw back out . If you do this & the screw wont come out . ?Take your soldering iron put it the highest setting & touch the screw for a minute or so . you should know be able to back the screw out .