magnetic propeller balancer

http://www.instructables.com/id/Magnetic-propeller-balancer/

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Magnetic propeller balancerby Danijel0frk on March 15, 2014

Table of Contents

Magnetic propeller balancer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

Intro: Magnetic propeller balancer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

Step 1: First things first . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

Step 2: Stuff and tools . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

Step 3: Disassembling hard disk drive - harvest magnets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

Step 4: Disassembling hard disk drive - harvest metal axle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

Step 5: Rack server - harvest hdd case . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

Step 6: Drilling time . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

Step 7: Steel some pens . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

Step 8: Sharpening metal axle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

Step 9: Finalising . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

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Advertisements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

Comments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17


Intro: Magnetic propeller balancerSo you have spent a lot of money on your diy quadcopter(or any multirotor) and refuse to give any more, but you still need a propeller balancer. Balanced propeller isvery if not the most important thing for multirotors.

Guess what, you can make your own, from old computer components.

If you happend to work in ICT company, there is always a lot of that stuff around. Besides broken hardware, some tools may also come handy. Let's begin with stuff youare going to need.

Step 1: First things firstIf you are lazy and don't care about 20 bucks, go and buy propeler balancer. Go for a booze right away.

Step 2: Stuff and tools1. Piece of wood,

2. Set of screw thingies,

3. Drilling machine,

4. Handsaw,

5. Angle grinder,

6. Broken DVD writter,

7. 4x Hard disc drive,

8. Rack server,

9. Hammer,

10. Ruler and


11. Sandpaper.

12. 2-8x Pen

Image Notes1. Piece of wood

Image Notes1. bowl of screws

Image Notes1. Set of screw thingies


Image Notes1. Drilling machine

Image Notes1. handsaw


Image Notes1. angle grinder

Image Notes1. Broken DVD writter

Image Notes1. rack server


Image Notes1. Hard drive drive


Step 3: Disassembling hard disk drive - harvest magnetsDisassamble hard disk drive with appropriate screwdriver. Make sure you have made backup before. If you are stuck with some plastic hooks, take hammer and brakethem. Repeat as many times necessary. Don't worry about hammer and you can't overdoit smashing hard drive. Now if magnet is free to take out, take another hard diskand repeat this step 3 more times.

Now you should have 4 magnets. If you have less, you don't know how to count or you dissasambled some SSD or whatever.

Image Notes1. Magnet

Image Notes1. 4 magnets

Step 4: Disassembling hard disk drive - harvest metal axleUse screwdriver to unscrew all screws. Now, it won't allow you to open it just like that. Help yourself with hammer, convince him. Eventualy all vital electronic parts willmove away in several dozen pieces. Take out shorter axle and throw away smashed DVD writer into garbage(recycle!). Or you can intall into colleagues PC. Either way isok.


Image Notes1. You want that axle

Step 5: Rack server - harvest hdd caseDownload manual for your rack server and find a way which one of 2 possible plastic handles enables taking out hdd case. After that, unscrew 4 screws or 5 or 6,depends on the case. All you need from this are two metal side thingies. Rest of the case you can put back into rack server. Then you can practice hammering on server.

Image Notes1. hdd case


Image Notes1. Side metal thingie

Step 6: Drilling timeFind somewhere in the workshop 3mm bore. It will fit with almost any screw from bowl of screws.

Most certanly you will find 2mm and 4mm. If that is the case, call your boss and tell him that workshop doesn't have 3mm bore. Then go to the hardware store and buy it.Next day you will notice few evil eyes in the office.

Make two holes on each side of wooden piece with cool black stripe. Make sure those wholes actualy fit in metal thingies from hdd case. It is recommended to use angleruler. If you have sharp eyes and good normal ruler, it will be fine. I didn't have angle ruler.

So now you have 2 holes. Take 4 screws from bowl of screws. Screw them. Screw them good.

If everything is screwed good, you will have 80% of the final product.

http://www.instructables.com/id/Magnetic-propeller-balancer/Image Notes


1. good screwed screws

Step 7: Steel some pensSteal 3-4 pens from office. Don't use your pen, it's more fun to steal from colleagues. Next day they will be surprised. Blame the janitor the cleptoman.So now you are full of adrenalin because you stole 3-4 pens. Unscrew(without screwdriver) pen tip thingie. Use the adrenalin from stealing and take sandpaper andsandpaper them. Also sandpaper them goood. The point is, we need get enough big whole for pen tip thingie go through metal axle from dvd writer. If you overdo it, goand stil some more pens. Enjoy the extra adrenalin. Feels good? :).I hope the office had enough pens for you to make 2 sandpapered pen tips thingies.

Image Notes1. Stolen pen

Image Notes1. pen tip thingie

Image Notes1. pen tips, after good sandpapering


Step 8: Sharpening metal axleRoll your sleeves and take angle grinder. Each second you are becoming a more manly man. Beard is growing 1mm/hour. Grind metal axel to get sharp edges. Grind ituntil is about 5mm shorter then U profile made from piece of wood and 2 metal thingies. If you wish, you can use handsaw for shortening first, then grinding to get sharpedges. Either way is ok. Depends how much beard do you want to grow that day.

Now you are 95% finished.


Image Notes1. optional handsaw, beardkiller

Step 9: FinalisingRest 5% is asembling magnets on metal thingies. Put pen pins into metal axel with propeler between. Friction will help to stick 3 things together.

Congratulations you are finished. 20 bucks stays in pocket, speend it on booze.

May you multitorors fly without any vibrations and the force be with them.

p.s. Stolen pens problem have few solutions. Burn them! Blame on janitor the cleptoman. Take a vacation 2-3 days.


Image Notes1. Two for tango on each side of metal thingies.

Image Notes1. magic gap


Image Notes1. Tadaaaa

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Comments49 comments Add Comment

graydog111 says: Apr 23, 2014. 7:31 AM REPLYGood Instructable. I am now hunting for two big magnets to balance my lawn mower blades. http://www.instructables.com/id/Lawn-Mower-Blade-S... I haveone 12V electromagnet I made that will lift about 250 lbs, but too much work to make another. Any suggestions?

NAVIGATEUR says: May 8, 2014. 1:39 PM REPLYHarbor Freight Tools has magnets at a reasonable rates. Hope this helps

motions says: Mar 15, 2014. 4:25 PM REPLYOops. Friction.

1966smiley says: Mar 25, 2014. 1:09 PM REPLYStep 4: Disassembling hard disk drive - harvest metal axleThat should be not hard disk drive

Should be cd or dvd drive

your_dragon113 says: Mar 25, 2014. 5:19 PM REPLY3 1/2" Floppy Drives as well...

morsed2 says: Mar 25, 2014. 8:35 PM REPLYWhat is a floppy drive?

c13378 says: Apr 11, 2014. 7:50 AM REPLYits a flying car!

your_dragon113 says: Mar 26, 2014. 8:26 PM REPLYlol....yeah, I know....I'm showing my age now. hahah

morsed2 says: Mar 26, 2014. 9:55 PM REPLYI am older than you I bet!

Nice instructable, I don't have a large quad copter, but my roommate does, and I am going to show it to him, maybe even have a go atmaking it.

When I started work in the US, I was using 8 inch floppies, beat that if you can. And my very first hard drive drive as a 20 MB, ST225.20MB, YOU CANNOT BUY THUMB DRIVES THAT SMALL TODAY.

(Glad you took the last comment as a joke)(and I lived in a paper bag in the middle of the street)Later everyone

altomic says: Mar 30, 2014. 5:53 AM REPLY(and I lived in a paper bag in the middle of the street)Luxury!!!

mayra6385 says: Apr 2, 2014. 10:10 AM REPLYSad ?u te tuiti tvrtci NoviNet da si im ukrao kemijsku!!! :D

JayGeeBSE says: Mar 30, 2014. 5:42 AM REPLYTo the person who commented that this only produces static balance, and not dynamic: Please note that the thickness of a propellor (IE the along-axismeasurement) is tiny compared with the diameter, so there is very little scope for the dynamic balance to be significantly out. Not worth worrying about. Incontrast the long thin arnatures of slot cars really need dynamic balancing. As far as I know until recently you could only do dynamic balancing withelectronic vibration sensors and electronic flash. Recently I saw a way to do it (was it on Instructables?) using the vibration sensors in a smart phone. Butlimited to items you could balance with stick-on tape, and that does not include armatures.


fabelizer says: Mar 27, 2014. 4:30 PM REPLYVery entertaining read! Thanks. Nice project.Could be a fun motor too! Electronic commutation anyone?

enriqueconde says: Mar 27, 2014. 3:05 PM REPLYVery nice but be aware that this is only static balancing!

clazman says: Mar 27, 2014. 7:44 AM REPLYAgain I was enticed by the headline to view a nice piece of work with high precision components only to discover the use of a scrap of low tech low precisionwood. Don't get mewrong, I enjoy items made from wood. This is NOT such a place.Why not use the power supply housing or maybe the drive housing?

vincent7520 says: Mar 26, 2014. 2:51 PM REPLYWhy do you have to steal a pencil ?

Stealing is wrong, even on the internet. ;))

rimar2000 says: Mar 15, 2014. 8:13 PM REPLYYou don't explain how to use the device. I think that it does not work.

Bill WW says: Mar 26, 2014. 1:39 PM REPLYAt first I thought I would not understand because of all the computer hardware terminology like HDD, Rack Server, SDD, still do not know what is an ICTcompany.

****

Al principio pens que no lo entendera porque de toda la terminologa de hardware como HDD Rack Server, SDD, todava no s lo que es una empresaTIC. Pero, entiendo "sierra", "lapiz"...

Bill WW says: Mar 26, 2014. 1:28 PM REPLYIt took me a while to understand, but yes, a static balancer held by magnetic field. A very interesting concept.

My concern (posted above previously) is that the axle or other components may not be on center. Best would be to use the same axle as in the actualengine, or identical.

***************

Me tom un tiempo para comprender, pero s, un balanceador esttico realizado por el campo magntico. Un concepto muy interesante.

Mi preocupacin (publicado anteriormente anteriormente) es que los componentes del eje u otros pueden no estar en el centro. Mejor sera utilizar el mismoeje como en el motor real, o idntico.Buen dia, amigo.

Danijel0frk says: Mar 16, 2014. 3:02 AM REPLYPropeler balancing is more or less known only in rc circles.In a nutshell, the goal is to identify heavier side of propeler, and thensandpapering heavier or putting tape on lighter side. Also there is aprocess of hub balancing.I might record a video how this diy balancer works with explanation how magnetsprovide almost frictionless axle turning :)

larz001 says: Mar 25, 2014. 1:20 PM REPLYon the contrary sir , even in the real world propellers need to be balanced, I have been working in the aircraft manufacturing industry for over 25years and an aircraft cannot be certified to be airworthy unless the propeller has been inspected and balanced by a certified aircraft tech, after wichthey will affix a certification stamp of airworthiness ,, this certification law has been in effect since 1945

criggie says: Mar 25, 2014. 1:52 PM REPLYDoes the certification stamp unbalance the formerly-balanced prop ?


larz001 says: Mar 25, 2014. 2:24 PM REPLYlol no it doesn't, once the alcohol in the ink evaporates then the remaining pigment wouldn't weigh enough to make a difference

larz001 says: Mar 25, 2014. 1:24 PM REPLYalso I loved the ible,, I have owned the topflight mag balancer for over 20 years now and love it, wish I hadda thought of this 20 years ago lol

Penolopy Bulnick says: Mar 24, 2014. 12:05 PM REPLYI would love to see a video!

rimar2000 says: Mar 16, 2014. 5:48 AM REPLYThanks, I know what is static balancing and dynamic balancing too, both are used in all devices that have high speed rotating parts, not only in RC.But I have not any idea how you could use your device. Maybe it is the best of all, maybe it does not work.

Being Instructable an "all purpose" site, your instructable is read by many persons like me, that have no knowledge about RC but are interested ingood ideas.

Danijel0frk says: Mar 16, 2014. 11:48 AM REPLYI appreciate your comments, you are absolutely right. After all this was my first "instructubles" . For example, axle must be perfectly horizontal andperpendicular to both sides(magnets). Also cones must provide perfect vertical spin of propeller. Any imperfection of the hub must be somehoweliminated. Any little variation will give false results. Soon i will make an update with some pitfalls and explanations about workings.

rimar2000 says: Mar 17, 2014. 5:39 AM REPLYNow I am understanding your proposal. Your device is a static balancer. Good idea to use magnets, but your axis should be turned by a goodlathe, not by hand.

A common error (not yours) in this method is to think that the propeller MUST BE horizontal to be balanced. If it is the case, the propeller isunbalanced laterally. You must do a large series of measures, ensuring that the propeller stops in DIFFERENT positions each try.

Static balancing is problematic and difficult.

rimar2000 says: Mar 17, 2014. 5:43 AM REPLYAs a newcomer in Instructables, you should know that later additions to your post will be seen by few or none persons. You must wait tofinish the instructable BEFORE publish it.

Danijel0frk says: Mar 17, 2014. 6:31 AM REPLYThis diy project is based upon several videos and articles about balancing propeller. Your explanations go way beyond those instructionsand understanding. If you have good web resources, please post it, so everyone who reads this instructable will know to which level isthis balancer precise and what are the drawbacks and errors.

I'm working on a solution which will provide better precision with common tools, but won't go to the scientific level of precision, becausebalancers for RC in this price range don't provide that. Also there must be a way for calibration of balancer.

rimar2000 says: Mar 18, 2014. 4:56 AM REPLYNo, I have not web resources. I only tried to do propeller balancing a few times. Your idea is good, but if the axis have 0,01 mmeccentricity, it will work against you. Its mass also matter, lightweight is better.

Poppy Ann says: Mar 26, 2014. 3:42 AM REPLYThis sounds easy but the problem is unless the pen thingy's are a very very good fit then they will be out of center, I bought one (or) two genuine magneticprop balance's and even on them they are not that good unless you get one that the holders are tight on the shaft i noticed if i balance the same prop that italters every time i do it due to the holder having a loose screw thread.

a quick tip on grinding the center axle to have a point is hold the axle in a electric drill and grind it whilst it is turning.

also you can pick one up from hobby king for $6.72 product id: 171000401-0another thing to watch out for is hitting a magnet hard will de magnetise it so don't hit it to much with a hammer.

but all in all a good instructable.

Bill WW says: Mar 26, 2014. 1:10 PM REPLYYou said: "unless the pen thingy's are a very very good fit then they will be out of center." Exactly my thought also. This Instructable will do an excellent jobbalancing the entire assembly of propeller, pen thingy's, and axle. But the pen thingy's and axle could be suspect, because yes something may be offcenter. The test assembly may not be identical center or alignment compared with the actual propeller shaft and bearings.


Bill WW says: Mar 25, 2014. 10:53 PM REPLYIn the intro photo, is the left hand side of the axle levitating? Wow!

onemoroni1 says: Mar 25, 2014. 8:16 PM REPLYAhh yes, manly man activity with tools! Nice build.

maxom says: Mar 25, 2014. 5:49 PM REPLYAfter looking at this, I believe if I need a prop balancer, I would definitely go shopping.

cepterbi says: Mar 25, 2014. 12:02 PM REPLYhad fun reading. don't have a helicopter so i'm good anyways.

Perspective Image says: Mar 25, 2014. 11:38 AM REPLYToo funny! The excellent sense of humor is only exceeded by your imaginative and useful creation of this very useful device. Hats off to a great instructable!

perfo says: Mar 25, 2014. 11:30 AM REPLYnice instructable with a good bit of humor, thanks.

LancasterPA says: Mar 25, 2014. 11:25 AM REPLYHa, Ha, I thought this was for a real airplane propeller. What was this guy going to do with all these little things. My propeller is 60 inches. Maybe back in theday when they were getting rid of Univac's the parts and magnets would have been big enough.

danallen82 says: Mar 25, 2014. 10:59 AM REPLYBeing someone who also made his own balancer, I love it! The only thing I don't agree with is the way you made the shaft and cones, I do however agree withthe pen theft ;). I just think that you should buy the really inexpensive balancer shaft with cones. http://www.hobbyking.com/hobbyking/store/__14927__...This one only requires sharpening the tips to a needle point, and some subtle balancing of the cones.

JDEVONE says: Mar 25, 2014. 10:47 AM REPLYThanks for such a wonderful idea. Your instructable was easy to understand and a little funny. This requires a vote and I voted for you. I will be using thisidea. Keep up the fantastic work.

BurgersBytes says: Mar 25, 2014. 9:05 AM REPLYSure everybody has 4 hard drives just laying around waiting to have their magnets removed. So now that you have made the thing, do you plan to ever getserious and use it?

ajarworks says: Mar 25, 2014. 8:53 AM REPLYNice, witty, instructable. There's not enough humour in this world.

I'm going to pass this on to a mate who builds serious RC aircraft (twin engine 5' wing span jobs) thanks.Love the magnetic bearing, got to be the ultimate in low friction

jcduplessis says: Mar 22, 2014. 4:00 AM REPLYExcellent instructable. (Especially if it is your first one!) You give a very "do-able" solution to a very common problem with rotor blades. I recently built myvery first quadcopter and am currently having a lot of issues with one of the props not being properly balanced. Although these motors are generally veryrobust, the unbalanced prop has caused severe wear on my motor to the point that I will have to replace it. If I had a simple device such as yours, I wouldprobably not have had this issue!

Point being.... for your everyday type quadcopter, the level of accuracy that your device offers, is more than sufficient.

It is sad to see that the more experienced members can only criticize your work. How about trying to give words of encouragement and some positivecriticism. (As our "be nice" policy requests) This instructable embodies the spirit of this whole website nl: to re-purpose or create from nothing (or scrap)something that is worthwhile and then to share that knowledge for free.

jobard says: Mar 25, 2014. 5:58 AM REPLYI'm sorry, I'll have to disagree with you. I believe rimar2000 was only trying to stress the numerous problems one can face while balancing a propeller.Indeed, the precision he is proposing goes way beyond what is expected in a 3-4000 rpm RC brushless motor (perhaps to 18000+ rpm, it would mean a lot),but if we consider all these variations, although not exactly required, the quad would be perfectly balanced.

I couldn't notice any "bad" criticism on his behalf.


Nomilli says: Mar 21, 2014. 11:45 PM REPLYYou know it almost seems like something that would be fun to have as a desk toy.

motions says: Mar 15, 2014. 4:24 PM REPLYGreat idea and project. You can get a really accurate balance with no fraction like other balancers. Kudos!!!

cortexmille says: Mar 21, 2014. 2:30 PM REPLYhello.please post a video of the device while it is working. Pierre

magnetic propeller balancer

Documents

penimage notes1

magnetimage notes1

hard drive drivehttp

hard disc drive

drilling machineimage

hard diskand

piece of woodimage notes1

angle grinderimage notes1