Hezik
Yes my props are always balanced, my good flying friend always reminds me to do it.
He also has a Wind 110 with the same A50-16L set up. His Hacker is now also making the same noises.
When you strip these things down you find that the bearings are doubled ie. 2 of 10x6x3 mm each end.
This is probably because they are the L (long versions).

I get no vibrations at all, only bearing noises.

Don't understand your point about wing incidence in relation to my question?

Have you stripped down one of these motors does anyone know how to put the shaft spacers
back in the correct sequence?

Thanks & regards
Colin

My wing incidence question wasn't related to your question. It was a seperate issue.

I had one Hacker that didn't sound too good, but it wasn't the bearings, it was the tunnel they are mounted in in relation to the coils.

Hacker uses a pin to keep them together, but there was some room on this pin so the engine woult vibrate on spinups.

Can't explain it in English, I'm dutch.. but here's a video of what I mean.

http://www.youtube.com/watch?v=onzZA...layer_embedded

I fixxed this by glueing the two together (using UHU Endfest), engine has run flawlessly since (this is the engine that has over 500 flights on it). After about 520 flights, the axle broke mid-air, a typical metal fatigue breakline. In it's life the prop might have touched ground like 3 or 4 times when taxiing, it probably developed a hairline fracture then. Also, we pull roughly 1.8kW, and it's a 6mm axle.

Update from the SoCal Wind 110 experiment.
Installed a new Scorpion 4035-250 last week. First couple of flights the motor was very warm, almost too warm to touch.
So I trimmed off the nose of the spinner (left a 1.125" dia hole) to let air into the motor area. When I looked thru the spinner hole towards the motor I realized there is only a small passage way for air to actually reach the motor. I also noticed the front of the motor, the stationary end which is bolted to the firewall where the air inlets are located, is obscured from direct airflow from either side and below by plywood doublers. Hmmmmm. I took out my trusty dremel sanding drum put a radius on both the left and right side doublers. Not a big hole, and not near the firewall dovetail, but just big enough to let air thru. Now I can see the motor's air inlets thru the cheek cowl holes. I also opened up the cheek cowl holes coming forward toward the spinner and I opened a new hole in the canopy top thingy right above where the motor wires come out.

I bonded a thermocouple to the front of the motor and took the attached data. I used a 17X12E and 18X10E APC. The motor was much, much cooler. I wish I had put the T/C on before I perforated the front of the plane for a true comparison. But it was much cooler than before. Session 5 is with an 18X10E and session 3 used a 17X12E. The 18X10E used more amps, but not that much more. The temp is about the same. At the end of each flight I taxi in and it appears thermal soak is responsible for the increase at the end of the plot. I liked the 18X10E, it seemed to fly slower and more deliberate.

I also ditched the third bearing in the plywood bulkhead. I know, sacrilegious.
"I felt like a monster reincarnation of Horatio Alger ... a Man on the Move, and just sick enough to be totally confident!

Hello Bedowinn

I am about to start my Wind 110 build. I am curious if you are using 10S or 8S batteries? Also could you explain your decision to not use the third bearing in the plywood bulkhead? I am planning on a 5000mAh 8S setup with the Scorpion 4035-250. I am going to do the same thing as you and use my dremel to open up some cooling for the motor.

Cheers

MJ

I chose 10S because I am a cheapskate and do not want to buy 8S packs now and 10S packs later when I get a 2M plane. I think you are well off using 8S packs. They are lighter and potentially less expensive. Either way you cannot lose. This plane is a great value and you have several choices for a motor.

The third bearing support barely fits on the end of the 4035-250 shaft (the Hacker motor is a bit longer I believe). You probably have to modify it as I did to position the bearing closer to the motor. When I mounted the bearing bulkhead I made sure there was no preload on the shaft before securing the bulkhead mounting screws.

I am not running the bearing now and will let you guys know if I come to grief over it.

Just be careful removing material from the doublers. I really think it helps airflow into the motor. Plus I needed to remove some material from the top as that is where I routed the motor wires.

I highly recommend getting some carbon pushrod kits from Central Hobbies or equiv. and some nice BB rod ends. The stock stuff is...well.........did I mention it flies great?

This and a buck will buy ya a cup of coffee . . . but for what it is worth I had a conversation last weekend with an FAI level competitor who frequents this forum regarding the cooling holes that are in my spinner. His remark was that he tested this concept several years back by cutting off the nose of his spinners and then tested the resulting change in motor temperature, and his finding was a difference around 5 degrees Celsius which he felt was meaningless in performance or motor health. Also given that the Scorpion is rated to 200 degrees C (392 degreesF) I would be genuinely surprised if anyone was able to "burn up" a Scorpion. Killing the motor with vibration from poor mounting or from an excessively heavy and unbalanced prop seems waaaay more likely . . . but again all that is opinion and hearsay so take it for what it is - an attempt to further the learning on RCG

Keep the buck, I don't drink coffee.
The motor was mounted per the instructions and the mounting hardware checked before each session. I balance all my props (APC 17X12E) and the airframe never vibrated excessively. Do you have any other theory you would like to advance? In the interest to further the learning here on RCU of course.

FWIW, the airflow thru a spinner to the motor would depend on the mounting setup, wouldn't it? And in the case of the Wind 110 this path is obscured by the front firewall. Either way, I'll take the 5C reduction. I now have a direct path (cheek cowls) for airflow to reach the motor. Guess what, it runs cooler.

I spoke to the Scorpion rep and he came up with some possible scenarios for this failure. The current draw and watts used should not have caused a failure. I can tell you it was too hot to touch after it's last couple of flights. It is entirely possible my first 4035 died from harmonic vibration induced at the rear bulkhead bearing or a problem with this particular motor.
This is not an opinion or hearsay, I was there and I'm describing what I experienced.
At this point the fact is I do not know what the exact failure mode is. But if and when I do find out, you'll be the first to know.

First flight a huge success!

I finally got my Wind in the air. It exceeded my expectations. Wow this thing flies on rails. Plenty of power on 8S with the recommend A50 Hacker. Climb straight up without slowing at about 55% throttle. Downlines were smooth, and I could keep a constant speed. The 18x10 prop seems just right. Winds were 7-10 mph, but I did not notice it. Stalls are gentle and never dipped a wing. My CG is at 183mm, and this it feels a little aft for me, but I will try to keep it here for good snap rolls. I didn't need any roll or rudder trim, but I did need some nose-down elevator. The elevator just need two click of nose down, and the control surface is down about 1/2mm.

I burned 1850 mah in 5 minutes of easy cruising. My batteries are only 3600 mah, but now I think this is plenty.

I followed the manual on pattern control throws; roll rate was way too high, so I will reduce the aileron servo control arm length. Rudder and elevator were fine.

I can't wait to fly it some more and do some KE flight. I had to stop after one flight due to rain.

Thanks for the report Tony, hope to see you and Steve flying at the FARM contest this weekend.

I had the same problem with a Turnegy , had to glue the bearings with some Locktite(dont rember Which type I used) and that lockeed the bearings really nice .When the engine was mounted in the airplane I could feel about 5mm sloop in the tips off the propeller.
That gave the engine a lot off vibrating noice

Outstanding!
Did you have to add any tip weight?
I slowed my low rates down to 8 deg on the Ail, and 10 on the el.
FYI I have the CG around 7.15 to 7.2"
Will you be flying any Pattern contests?

Mike

Thanks to all that replied to my question.

I received an answer re my A50 -16L rebuild from Hacker USA.
Many thanks to them for their quick response. Had no reply from Hacker Germany. (poor - don't care?)

Ok so here is how if you need to rebuild, for bearing, bent shaft or glue that common loose stator pin.

1.Press your shaft back into the housing (rotor which contains the magnets) It is always worth removing the shaft to check if it's bent.

2.Press in your REAR bearings, x2 of into the end of the stator hub.

3. Drop your longest brass spacer into the Stator.

4. Press your FRONT 2 bearings into the front Stator hub. You now have the long spacer between your bearings.

5. Slide the whole Stator assembly over the shaft into the rotor housing, take care hold it tight, the magnets can pull it in rapidly.

6. Slide the second short brass spacer over the shaft folowed by the front end plate/cover.

7. Place the brass thrust washer next followed by the circlip.

8. I was advised to press the shaft back slightly onto the circlip before then putting in the 2 shaft grub screws.

9. Replace all the screws with blue thread-loc, 2 grub screws, 4 small housing screws, 4 fan screws & 3 endplate screws. Remember to clean off any old thread-loc first.

Note: my front and rear refences are relative to the Wind 110 mounting. (I know brushless motors can be mouted both ways)

I hope you find this helpful should you ever need to strip your motor down yourself.

I will not be so stupid next time as to let all the spacers drop out before I take note.

Regards
Colin

Many thanks to James Gallitin -Aero-model - Hacker Brushless Motors USA, for the information.

Hey Guys

I am just installing my Scorpion 4035-250 and I just want to know how many of you opened up the motor shaft hole in the firewall to accomodate the collar on the Scorpion motor. I think that Wilson took it off and mounted it on the back as a spacer for the third bearing but it looks like there is a spring washer between the collar and the front motor bearing. I would rather keep the collar as it is with that in mind. Opinions??

Cheers

MJ

MJ,
I would leave the motor alone. I think you could relieve the opening with a dremel sanding drum.
But to be sure call Scorpion USA at 760-468-8838 and ask for Lucien for his opinion.
Let us know how it works out.

Mike

I talked to Lucien, he said to open up the firewall and keep the retainer on the motor.

I cut the ears off an aluminum motor mount, installed it on the firewall, and used the hole as a template for dremeling the hole. There should be some pictures back in this thread.

I actually need to double check my retaining collar; I noticed (by accident) that I am able to push on the spinner cone and move the shaft in and out of the motor a little bit. Would be a lot worse without the retaining collar (I think).

Bedowinn,
Thanks for the info. I will be flying this weekend at the Virginia pattern contest at the FARM. I am in the Intermediate class.

Thanks for the info Joe.I was about to call Lucien myself but you saved me some dough on the phone bill!! I have opened up the firewall. I used the prop adapter as a guide and just drew around it. Worked well. Did Lucien mention anything about using/not using the third bearing on the aft part of the shaft? To me the firewall looks skookum enough and I have run a bead of thin CA all around the firewall and it's attach points. I am leaning towards not using the third bearing asI dida really rough balance on the motor with the prop and spinner on it and the motor balances just aft of the front gold fixed plate. With this balance point I doubt there would be any benefit in using the bearing and may introduce more problems that it is worth (including installation which looks like a real PITA after modifying it to work). Bedowinn..........any reports on the outcome of your not using the bearing??

He never answered that question, but I use the third bearing and no issues yet. I think I CA'd it in the plywood support.

Also, +1 on the crappy canopy. A day in the car and it bent and now doesn't sit right, plus a crack in the side near the turtle deck.

Don't let us down!!
Knock em dead!

Mike

Bedowinn..........any reports on the outcome of your not using the bearing??
[/quote]

The front of the plane fell off from the bearing bulkhead forward. The good news is the CG is now perfect and it KE straight.
Just kidding. 10 flights all is well, motor runs cool, smooth, and no funny noises except from the other GF and gas guys.

Dude,
My canopy cracked as well, actually a 1" piece with a shallow radius broke off mine.
I'm sure if I complain they'll comp me with a 2M plane. Which BTW are headed toward the Fruited Plains next month.
Are wanna be pattern fliers entitled to any stimulus stash??

Hey Guys

I just installed my motor. I wound up putting some 1/8" spacers between the motor and firewall as there was just too big of a gap between the nose ring and spinner. Has anyone else done this?? I now have a 1/8" spinner/nose ring gap which is more asthetic than the 1/4"+ I started out with. I am a bit disappointed in the canopy fit as it is out of round with the spinner and has a larger diameter at the top by at least 1/8". Not a bad thing for function but it makes it less appealing to the eye. Has anyone else had this problem with canopy fit?

Cheers

MJ

I actually need to double check my retaining collar; I noticed (by accident) that I am able to push on the spinner cone and move the shaft in and out of the motor a little bit. Would be a lot worse without the retaining collar (I think).


Hi Joe

I just tried it with my brand new motor (never been run) and I can get the shaft and can to move back and forth a few thou too. I can see the movement when I push and pull on it. I hope this is normal?!?!?! My retaining collar is solid as a rock on the shaft. Anybody else with the Scorpion 4035-250 have the same thing going on?

MJ

Here you can see a side-by-side comparison of 2 airframes; on the left it's me flying P11 with the WindS 110, on the right side is Roy Oostema with the Krill Spark Dynamic.

http://www.youtube.com/user/rossie00.../0/mF3b4SSomGE

Both flights were flown right after each other, so in the same conditions. We had about 15 knots of wind, from left to right, slightly inward.

In the Dutch competition, top class, Roy is currently placed at 4th place, I'm 6th.

Anyone flying the Wind110 with the wing gates ? Like to install them, but think they'll get warpped out of shape in the wing bags. Opinions welcome. Love that quiet EL power, and can fly in the schollyard right out front of the house
I've had my Wind now for a few weeks, and find it to be as pleasent a flyer as I've had my hands on for the size.
Heres my school yard birds now