The shower knob in our guest bathroom was spinning freely, so I needed to do something fast. 

I quickly came up with a design that will work using 123D software (free).  The design and print files are available at:


Step 1:

Life is not perfect.  The hole in my first knob was too small.

Step 2:

Rather than redo my 30 minute design, I just "enlarged" the print to 119%.

Step 3:

The hole worked, but I had left too much "shoulder" inside and the screw wouldn't fit.  I did a two minute design tweak and printed again.

Step 4:

Put the knob on and screw it in.

Step 5:

Because my knob is long and does not contain a "stop" to limit its travel, I wrote the word "off" at the top shutoff position.

Beauty and a "stop" are desirable upgrades for the knob, but this is functional, costs about one dollar, and is more socially acceptable than a pair of vice grip pliers.

As a follow up, I found a way to repair the old knob:
This is great !!!. I had the exact problem once and ended up filling the broken knobndle with automotive "Bondo" and letting it cure on the shaft. Still works after 9years.
I repaired my knob using a printed ring based on the idea I got after reading your comment. I did credit you with inspiring the repair ring. <br> https://www.instructables.com/id/3D-Printed-Repair-for-Broken-Faucet-Handle/
Thanks! Its always good to bounce ideas around :-).
You should remove that knob, photograph it and write it up as an instructable. You could enter it in the &quot;Fix It&quot; contest and maybe win a 3D printer . .
That's a good cure! It gives me an idea--I wonder if I could print a custom size &quot;ring&quot; and hold the broken piece inside the original knob. I'm going to give it a try :)
Good job on ya! hard work paid off
Good job on ya! hard work paid off

About This Instructable




Bio: I am an author and a maker. Current projects include Santa's Shop and Little Friend (ultracapacitor powered robot) on hackaday.io. I'm working ... More »
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