Introduction: K'nex Balance Scale

Picture of K'nex Balance Scale

Here is a knex balance scale I made a few weeks ago. It's uses a simple pivot point and two arms. It has a pointer at the top along with a dial to tell you how far from balanced it is. It doesn't use many pieces so most people can build it. This is the first one I know of on the site so far. It uses two large baskets to hold the items being balanced. This can also be used for counting items of the same mass. Needless to say this has many uses.
Please tell me what you think.

Step 1: Part Count

Picture of Part Count

This doesn't use many pieces, but it's always good to have a part count.

Connectors: #
White 17
Yellow 3
Purple 24
Green 36
Red 2
Light gray 2
Orange 2
Gray clip 4
Tan clip 3
Blue clip 2

Red 6
Yellow 2
Blue 2
White 85
Green 58

Odds and ends:
Y connectors 4
Track splice 1

Step 2: The Baskets

Picture of The Baskets

In this step you will build the baskets. First off build this circular plate.Picture 1.
Next build these four things.Picture 2They are the same so it should be easy enough.
Now build this ring of yellow flexi rods and green connectors.Picture 3

Okay, Now add the four things to the main plate.Picture 4
Last but not least add the ring made in picture 3.Picture 5

Great, you have built one basket. Now repeat this step so you have two baskets.

Step 3: The Pivot Point

Picture of The Pivot Point

In this step you are going to make the pivot point of the scale. Here are two pictures of the same thing.

Step 4: The Arms.

Picture of The Arms.

In this step you will build the arms of the scale. First build this.Picture 1 Now build the hinge on which the baskets will hang.Picture 2 Then connect the arm with the hinge.Picture 3

Good job. Now repeat this step so you will have two arms and hinges.

Step 5: Hook the Arms to the Pivot Point.

Picture of Hook the Arms to the Pivot Point.

In this step we are going to hook the arms to the pivot point. Just connect the three green/red rods to the half circle connectors.Picture 1 Do the same with the other armPicture 2 and there you go.

Step 6: Build the Body.

Picture of Build the Body.

In this step we will build the main body of the scale. First build these two sides.Picture 1 Then add green rods to one of the sides.Picture 2 And connect the two sides together Picture 3

Step 7: Build the Dial

Picture of Build the Dial

You need to build these two things. Pictures 1-2You'll need them soon. And slide them together.Picture 3

Step 8: It's Time to Put It All Together. Part 1

Picture of It's Time to Put It All Together. Part 1

It's time to put it all together. First add a yellow/gray rod to the body.Picture 1 Then add white rods to both sides.Pictures 2-3 Now add the pivot point and arms to the rest of the body.Picture 4

Step 9: It's Time to Put It All Together. Part 2

Picture of It's Time to Put It All Together. Part 2

First add the dial to the body.Picture 1 Then add this brown/orange connectorPicture 2. Finaly we can add the baskets.Pictures 3-4 Do the same on both sides.

Step 10: You're Done!!

Picture of You're Done!!

Congratulations you're done!!

Now to use it just put things in both sides. You can tell it's balanced when the pointer points to the middle slot in the white connector.

If you have any questions let me know.


OlgaN2 made it! (author)2016-03-18

Excellent instructions! Thank you! Beats buying $30 worth of teaching balance scales

chopstx (author)2009-09-25

A kind FYI: Pictures 2 and 3 are misordered. I would appreciate it if you corrected this problem. Any way, Awesome! I am actually in the middle of building this now!!!!!!!!!!!!


I finished building it! It's so cool!!!!! Do you mind if I make an instructable using this?

I guess not. Do I get a little credit??

Well....................OF COARSE!!!!!


Just so you know, It's nothing special. It's just what a white rod equals and such(in weight of coarse!)

Ok sound cool.

Kinda boring but I need something to post.

How's it coming??

Sorry, I was working on that, but then I decided I would work on my SKAK.

Are you still going to work on it after the contest??

Um..........maybe, maybe not. I probably won't though. Why?

~KGB~ (author)2009-08-18

lol! just asking?

Killer~SafeCracker (author)~KGB~2009-08-18

It was 7:43 am. What time was it where you live??

~KGB~ (author)Killer~SafeCracker2009-08-20

it was 11:10

Killer~SafeCracker (author)~KGB~2009-08-20

Do you live in NY??

~KGB~ (author)Killer~SafeCracker2009-08-21

no. wish i did!

Killer~SafeCracker (author)~KGB~2009-10-24

A little late, but lol.

~KGB~ (author)Killer~SafeCracker2009-10-25


knex_mepalm (author)2009-08-20

i bought a set in aus and i think you copied the idea, but better than it, so maybe 2.0

I would never copy a set. There is no point in it. Also did you rate it down. Because it's down like 1/2 a star.

i rated 2.0*


It feels like so much more could be dont, but wan't I'll rate it 4* I changed my mine, its harder to make one than expected.

mettaurlover (author)2009-08-27

in step 2, you got pics 2 and 3 mixed up.

Thanks I didn't see that

knexsniper1 (author)2009-08-19

just wondering, but wont the arms collapse under all that weight? either way, great job!

That depends on the strength of your connectors.

i gues, good job!


lemonie (author)2009-08-18

Very good, since someone just asked me - how much metal can you load onto this (grams)? L

It will hold about 900 grams or 2 pounds per basket.

NYPA (author)Killer~SafeCracker2009-08-19

I bet it can hold a lot more with tan rods.

Killer~SafeCracker (author)NYPA2009-08-19

Yes, Yes it will

NYPA (author)Killer~SafeCracker2009-08-20

Too bad i only have one.

Killer~SafeCracker (author)NYPA2009-08-20

Yep I have like 6.

I'd like to see that (for how much it bends) - can you add a pic? L

Ya I'll try to get one soon.

2 lbs? that's an awful lot.

Owenmon (author)2009-08-19

Nice! this is a very good idea. 4.5*

Thank you.

No problem!

smilee (author)2009-08-18

Wierd there are two ofthese in my recent page!

Thats odd. Comments keep going away as well

s0lekill3r (author)2009-08-18

Nice, simple design. Great job.

Thanks man. Glad you like it.

~KGB~ (author)2009-08-18

pretty creative. 5

Killer~SafeCracker (author)~KGB~2009-08-18


About This Instructable




Bio: Im Killer~SafeCracker, I started using Instructables in 2009. I mainly post in the Knex world, but I venture out sometimes. Check out all my ... More »
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