Hard-mounting cameras - what goes between camera and frame?

[Dune]

I'm flying an f450 and shooting video on a Canon point-and-shoot.

Question Numbero Uno:
What are you looking for when selecting a material to go in-between the camera and the frame?

• Rubber
• Velcro
• Moon gels
• Nothing - just strap it on tight.
• Gasket material
• Cottage cheese

From what I can gather from other threads, you want something with a little give so it absorbs vibrations, but not too much. Not too thin, and not too thick. What is the ideal?

I'm currently using a ton of velcro. Velcro between camera and PCB, a velcro strap all around to hold it down, and a 3rd strap to keep it moving front-to-back a little. See pics (I strap it on tighter than it looks when I'm actually flying). A pretty rough setup - I'm especially unsure about how well that 3rd strap prevents front-to-back tilting. See the video below for a demo of the vibration I get. (This is with stock props; forthcoming APC props and balancing everything will also help a lot)

The protruding piece of the PCB is supposed to be flabby enough to contribute to vibration. I got some landing gear, and have a whole bunch of sketches I kinda want advice on for how I might hard-mount it beneath the center of frame using a little balsa jig. I decided the question I've put forward here really needs to be asked before anything else, though.

As a bonus, here is another video of vibrations on a windy day with a stupid/amusing crash.

 

[Stacky]

The x468 frame guys use carbon fibre rods through rubber grommets.
This gives a certain level of rigidity and then the assistance of a level of isolation provided by the rubber grommets. I get no jello on my gopro when its hard mounted via their rubber grommet system.

 

[Bowley]

I started getting jello on my f450 and gopro where I had none before, I found one of the motor shafts was slightly bent so I changed the motor, it did improve the jello effect but I still got a little. when I first used the setup I had no jello at all so I have picked up a couple of vibration causes, probably wear and tear on motors and props.
If your system is setup properly you should not get jello at all.
I have my gopro mounted from the underside using the standard clip mount. I added a sellotape padded sticky pad (in the absence of a gyro pad/tape) into the equation between the sticky backed mount and the airframe and jello was gone.
Interestingly when I added a tywrap for secondary retention because I was not to convinced of its security the jello came back. the vibration was transmitting thru the tyrap. First try to eliminate the vibration, check props and motors ets, if you cant get rid of it then try to absorb it. Somebody on here recommended to me the kyosho anti vibration tape. There are various anti vibe tapes on the market. http://www.amainhobbies.com/index.php/cPath/61_179/n/Radios-Accessories-Servo-Gyro-Tape.

 

[kloner]

I'm using zeal

but your gonna have to get alot closer than where your at to get any sort of clean vid. Start at the top and balance your props. once the props are balanced put em back on, hold your frame under the motor and spin them each. if you feel it in the hand below, your bearings/shaft/barrel aren't happy. if they all pass the feel test, go try it with reballanced props. if it sucks, repeat. Thats the only moving thing on the airframe. i can set a camera on my frame with velcro or hard mounted and it's almost perfect, just a little jello will come in descents or full throttle and the zeal helps smooth that out.

A really good way to look over your motors if you've crashed and don't understand is to arm the motors without props and let em stop, look down and watch the shaft the prop sits on and the outter red black thing (barrel) for trueness. i'll hold it in my hand and feel the bottom of each leg like when spun by hand, you'll feel the problem if theres a serious one, it'll shake and they shouldn't at all.

I was looking through mcmaster carr the other day and they had a bunch of vibration absorbtion bolts/nutts that were rubber between a bolt on either side, came in lots of sizes, bet you could find one that fit the threaded insert in your camera

 

[Dune]

Thanks Kloner. That is probably the best description of how to check if your bearings are shoddy I have read. All of my stock bearings are able to be felt through the frame when spun by hand. You can feel it go through the magnetic poles. I guess I should 6 or 8 of these bearings from boca.

Are some bearing oils better than others, or will any old sewing machine oil, etc. do fine?

It sounds like extra points of contact (e.g. my 3rd strap on top) is also a bad idea. The problem is the base of my camera is only about 15mm wide, so even with a strap running round underneath, it's going to wobble forward-back. To minimize points of contact I may use a tripod screw to attach it to a wider piece of balsa/plywood, then stick the entire piece of wood to the frame.

 

[kloner]

i got friends that just use a bolt through a hat bill for point and shoot, I almost tried this
http://www.mcmaster.com/#vibration-damping-sandwich-mounts/=g8ykfj


Been using triflow and have no problems. i was trying to use some 30 weight synthetic motor oil and that sucked, just didn't last. Boca sells some super duper something, never tried it

That front flap it's mounted on in general wiggles with weight on it

those posted were the wrong size, mine were 4x8x3 like this
http://www.bocabearings.com/search....nerOperator==&OuterOperator==&WidthOperator==

im running these
http://www.bocabearings.com/bearing-inventory/Radial-Bearings/2337/SMR84ZZ7-4x8x3

 

[Bartman]

the bearings we have in our motors are considered to be in low rpm use so it is better to use greased bearings instead of oil. oiling bearings that are already greased at the factory fouls the grease and will likely let the grease leak out more easily. i didn't believe this at first but in researching replacement bearings for my Avroto motors this is what I was able to come up with.
if the bearings are pregreased and are of a sealed construction then oiling isn't necessary and will actually shorten the life of the bearings.
if anyone knows otherwise i'd love to hear it!
thanks,
Bart

 

[kloner]

just looking at it from a normal guy point of view, if you had 16.8 volt 4s and you had a 950kv motor, full throttle is 15,960 rpm...... with a what do you call it, axil radial load with single row bearings. The only stuff i've been around brushless is scorpion and next to every motor from 300kv on up to 3500 kv motors say oil every 10 flights. i know for a fact the bearings come greased, i've ripped into them too. so that said, heres there video about it

Then theres boca, and heres there page on it
http://www.bocabearings.com/dropin....ss-motor-bearing-maintenance-installation.txt

All there bearings come pre greased, and they will wash it off if you ask them to. grease makes em stiff for a while. oil doesn't so some people wash em in alcohol then just oil em. I just had a problem in a 4035 400kv scorpion motor, was in a scale heli and hard to oil. it made it 20 flights and smoked the bearings.

Metal sides on bearings aren't known as being sealed, thats known as dust shielded. rubber dust shield would be more considered sealed

All that said i have 7 bearings sitting here that flew less than 10 minutes before i decided to throw em at the ground and smashed em. I just took and blew one apart with a pair of dikes so we can see exactly whats inside a dji 2215 motor bearing. I gotta post em from another putter, i'll be right back

 

[kloner]

View attachment 2769View attachment 2770View attachment 2771

is there grease in there? Definately not packed like a wheel.

BTW, the 4035-400 i burned up was running a governed 10,000 rpm, in scale heli rated for 3500 watts and never got over 1200 watts

I've got a suppo in a 3d plank i've tried to kill 20+ times. Break props left and right, replaced the prop adapter a couple times, and it runs hot after 10 or so flights so i drop a little more oil in it and it runs totally cool again till the same time. I can hear it as it wears off it's so beat up

The only time i've killed a brushless motor from oil was on a KDE direct NEU 1917, that's there big 10,000 watt output motor. i was having a vibration problem later found was a lash deal, but i dropped 20 or so drops of oil in a week period. the insulation on there inrunner was a cardboard type substance and the oil softened it and the stuff started flying out of the motor

I'm somewhere around flight 300 on my f450, running 4s on a 3s 2215 kit with 10" props most of the way. been oiling the crap out of em and it is running smooth as silk. my only complaint is after i put a little on, it always seems to land on my lens and give me a smear in view that flight. don't hover much, i've been full throttle alot racing around

All but 3 bearings on my 450 are abec7 from boca. 2 motors out of 6 i got from addictiveRC had notchy bearings. they could use a higher quality from the get go IMO

 

[Dune]

kloner man, thanks for helping me figure all this out.

I will probably end up buying some of those stainless #7's. Have you used any of those chromium ones? I am curious to learn what the operative specs are - ABEC I know from skateboards, but I wonder if it's possible to predict the performance of these cheaper ABEC 1's just by spec or if you really just need to try em out in our application. I am a little disappointed to have to spend like $80 to replace the bearings and have an extra set, maybe I can get by with something cheaper.

Bart, who do you work for? I'm still relatively new around here.

I'm thinking about trying to add some struts to the bottom of the PCB to make the front flap a little stiffer. Maybe two 1/2" x 1/4" x 5" pieces of balsa mounted in parallel fashion, with the 1/4" making contact. I wonder what adhesive would allow me to remove them easily while still being functional? Maybe loctite quickset epoxy would be ok, I'm not sure I could chisel it off though. Silicone glue would be nice, but there might be enough play in between to allow vibration. Hell maybe just a minimal amount of cyanoacrylate would be best.

 

[DucktileMedia]

What? no greasy hairy ball comments?

 

[kloner]

try some of the lower grade, see how they go. I can't believe how small them balls are in these bearings. like a small mechanical pencil lead width around. Crazy little.

I think going anything past what i used would be way overkillin it. these are super smooth but i'm not much of a crasher so if you were crashing, the precision making them last longer would be a mute point. These are smooth as silk, before i got them in i was swapping motors asap to a different brand but now have backed off making it such a priority. I wanna go learn to fpv it and i bet after a weekend, i'll have these dji motors crashed more than once

 

[kloner]

View attachment 2775

micro hairballs, i hit that bearing with dikes on an angle and the crap flew everywhere, this was all i could find. small

 

[Dune]

those posted were the wrong size, mine were 4x8x3 like this
http://www.bocabearings.com/search....nerOperator==&OuterOperator==&WidthOperator==

im running these
http://www.bocabearings.com/bearing-inventory/Radial-Bearings/2337/SMR84ZZ7-4x8x3

kloner man. Those bearings are not the right size. The ones in my motors are I think 3 x 8 x 4, just like people were talking about in that other thread. Did you get this mixed up, or does DJI have two different motors it has shipped out with f450 kits? I should have took the motor apart and checked beforehand, but shoot.

Bearing from the DJI motor on the left, unfortunate boca 4 x 8 x 3 on the right.

 

[kloner]

I have the 3s kit that came with the 2215 and mine are like i told ya, then mailman got his in the other day and his were wrong. Sorry bro, didn't know you guys got 3mm shafts, mine are 4...... Now i know,,,,

he said the 3x8x4 were what worked in his 2212

 

[kloner]

if they try dingin ya returning them, let me know and i'll give ya what ya paid for em and send them my way. can always use some spares.

 

[Dune]

Yeah I have the 2212. Didn't know there were different ones that came with the f450.

Stuff like this is why there needs to be a wiki. Could just go DJI f450 -> motors -> bearing replacements and see all the different kinds. Would be more work for someone to moderate, especially if there are disagreements or varying approaches, but instances like this are proof that there is just so much detail, the organizational system of the forum kind of breaks down after a point.

 

[mailman35]

the 2212s are the smaller 3mm center, i ordered them but ive had a ***** of a time getting them back in due to the fact that i cant pull the shaft out of the 2212 motor to reseat the pressure on teh bearings properly.

 

[Dune]

the 2212s are the smaller 3mm center, i ordered them but ive had a ***** of a time getting them back in due to the fact that i cant pull the shaft out of the 2212 motor to reseat the pressure on teh bearings properly.

What do you mean? So you've got it apart and replaced the bearings...now what? If it's hard to explain maybe I will just have to find out when I get some more bearings in.

I wonder if these different motors means that DJI put some better bearings in there stock? Probably being overly optimistic, seeing as how so many people in the other thread with my size bearings were talking about replacing.

In other news, I have a gopro mount with a normal tripod-like attachment and a zeal pad underneath. A little better. Tried it with 8, 9 and 10" APC's on 4s and the 10's were the best. I have yet to truly balance them though. I am such a novice that I run them into the dirt so often, there's no use. Practice makes perfect.