123D Secret Chamber Knitting Needles




About: Industrial Design student at Eindhoven University of Technology

This instructable shows how I made this 3D model of my own invention made with 123D design. The following text explains what it is and what you can use it for. I hope you like it! (This is the first time I used 123D design, so it is possible this instructable doesn't show the fastest way to create this model, it shows a way)

So, what is it?

They are hollow knitting needles with fitting caps. Also shown is a crochet needle that fits in the hollow knitting needle.

And why would you use it?

This model gives a solution to a strange problem I sometimes have: what should I take: knitting needles or a crochet hook. When I take  knitting needles, I feel like crocheting. When I take a crochet hook, I feel like knitting. When I take both, I lose my crochet needle. When I take none of them, well, that won't happen.

The 3D model can be found in the last step.

If you like the idea, I would really appreciate a vote in the autodesk 123D contest.

Step 1: 123D Design

First, get 123D design. I made this in the online version. You can find it here.

The directions for the crochet needle are shown step 2/5
The directions for the hollow knitting needles are shown step 7/8

When you have done this, open a new file.

Step 2: The First Cylinder

From the primitives basic shape on the right side, choose the cylinder. Drag it from the column to the left.
When you select it, you can change the size. Make the height 14 cm. 

Step 3: Cone, Resize, Fillet and Tweak

From the column on the right side, choose a cone. Put it on the cylinder.
Select the now created shape. Using one of the four small white dots, make the cylinder smaller, but keep ratio. When L and W show the same decimal number, change both of them to 0,4 cm. 
Using the fillet option (where to find it is shown in the pictures), click the join between the cone and the cylinder. Change the radius from 0 to 1.
Next choose the tweak option (where to find it shown in the pictures) and select the upper part of the cone. Just experiment a bit until you reach the right shape. The numbers I ended up with are: L: 0,01; W:-0,058; H:-0,1

Step 4: Add a Dome

From the right side, choose the dome. Using the white dots, change the length and width to 0,5 cm.

After that, place the dome on top of the other shape, position it as shown on the picture.

Before going to the next step, turn your view to bottom view, so you can see the underside of the dome you just placed.

Step 5: And Another Dome

Again, take a dome. Change the size to:
L: 0,25
W: 0,25
H: 0,20
Place it on the flat side of the other dome and position it as shown in the pictures.
It can be helpful to look at the other side too, just so you know it looks good on every side, not just on one.

Step 6: Finished Crochet Needle

So, now your crochet needle is finished!
Oh, and DO NOT forget to save!!!

To make sure it is one piece(not pictured), select the complete model. Then, at the bottom of the page, it says how many objects there are. If it says 1 object, you don't have to do this. If it gives a number other than one, go to the symbol with two cubes, on the left of the T, and choose group. Now it will say it is one object and you will be able to move it like one object.

Step 7: The Knitting Needles

Open a new file. Take the tube. Change the height to 34 cm. Then, take a cone and put it on top of the tube. Select the cone and change the height to 2 cm.
Use the fillet tool to select the join between the cone and the tube. Change the radius from 0 to 8.

This is the base of your hollow knitting needle. Next step will show you how to make the caps.

Step 8: The Caps

Choose the cylinder. Use the white dots to change the size to: L: 1,5; W: 1,5. The height stays the same.

Take a second cylinder. Change the size to: 
L: 0,6
W: 0,6
H: 1,25

Place the smaller cylinder on top of the first, bigger cylinder. Using the arrows, put the smaller cylinder down, so it extends above the bigger cylinder. 

Again, check if it is one object, if it is not, group the selected objects.

Step 9: Done!

In this step I've included some different material and colour options.
This is the link to my model:

Autodesk 123D Design Challenge

First Prize in the
Autodesk 123D Design Challenge



    • Frozen Treats Challenge

      Frozen Treats Challenge
    • Sensors Contest

      Sensors Contest
    • Fandom Contest

      Fandom Contest

    39 Discussions


    5 years ago on Introduction

    This is great! I need a replacement for part that was lost and cannot be purchased any longer. If I found someone online who still has such a part, how would I go about finding someone who could duplicate it?


    5 years ago on Introduction

    This is great - when you knit, you always need a crochet hook handy for dropped stitches, weaving in yarn tails, etc..... this way you have one with you at all times. Now to figure out how to put row markers, and stitch markers in maybe the other needle...
    Great job

    1 reply

    5 years ago on Introduction

    ADDENDUM TO 'SNAP AND TWIST' IDEA... Don't try to go into manufacturing on your own. PATENT PEND your idea RIGHT NOW - it can be done in a day or so. THEN - contact the knitting needle manufacturers with your idea, offering it for sale. Before you do that - contact someone in the industry to try to get an idea of the VALUE of your idea - so you don't sell a million dollar idea for a few thousand dollars. Go to legitimate sources - like big-time patent attorneys and/or manufacturing groups in this arena. Call a local attorney who handles patents, and see what he/she suggests - and they might 'handle the deal' for you. PUSH TO GET IT DONE SOLD NOW - before Thanksgiving at the latest. There is very little time left, but if I told you what's getting ready to happen, you'd think I was a 'conspiracy theorist'... aka TRUTHER. Good luck!

    2 replies

    Reply 5 years ago on Introduction

    Patents are killing Innovation/Invention in the USA.

    Also, he released the design files under a CC License--he, nor anyone else for that matter, cannot go and get a patent for it.

    Stop. Pushing. Patents. Start pushing innovation.


    5 years ago on Introduction

    As a looooong-time knitter (50+ years), I've slowly graduated AWAY from large needles (#8 and above) unless for special patterns. Most of my knitting is now done on very SMALL needles (#1-3, maybe 4) for socks, #5-6 for light-weight tops, shawls, etc.) Decreasing the size of the INNER crochet hook to fit into such small needles would likely make it very flimsy. BUT - What if the inner chamber held only a METAL CROCHET TIP that would 'snap and twist' onto the END of one needle (like the connecting tips and cord kits you can get)??? NOW - the REAL trick is to adapt this idea to possibly ?fit INTO? a 'snap and twist' type needle tip....so you have 'grown up' CIRCULAR needles with a built-in crochet hook! Most serious knitters use circular needles now - they get tired of those 'flapping ends' on straight needles, and circulars hold huge amounts of sts for one piece cardigans, afghans, etc. The built-in crochet tip would be used for: picking up sts on side edges, fixing dropped sts, unraveling ONLY 1 stitch at a time by allowing it to 'drop' down 2-3 rows, when you K'ed and should have P'ed, then bring the correct K or P st 'back up the ladder' to the needle.... on and on. CONSIDER THIS, TOO: Create a 'set' of knitting needles (incl the circular snap & twist tips) AND a matching crochet hook that SNAP TOGETHER like those 2-channel needle tip holders that allow you to snap needle tips together, so you block the sts from coming off the needle at the same time that you FASTEN the two tips together. GOOD LUCK! GET A PATENT NOW!!! NOW!!! DON'T WAIT - SOMEONE ALREADY WITH MANUFACTURING ABILITY WILL STEAL YOUR IDEA YESTERDAY! PS - I get the first sz 2-4 set!!! (big grin)!

    2 replies

    I think that could be possible, usually I knit and crochet with 3.5 mm (my favourite size, that's also the size of the crochet needle) but lately I've been working with T-shirt yarn :)
    I love love love your suggestions, but it would have to wait. I made this during my vacation and went back to school today.
    Fact is that getting a patent where I live is expensive.
    So, at the moment it had the instructables license, that means:
    You can copy, distribute, display and perform the work, you must give the author credits, you may not use this work for commercial uses.


    5 years ago on Introduction

    Excellent! Since I crochet and knit I could definitely use a couple of these! I was caught in curious predicament the other day. I had packed crochet hooks and knitting needles, even remembered the stork scissors! When I got to where I was going, I suddenly realized I had no yarn! I'm not sure what the solution to that problem is. (Other than "don't be a ditz"!) Great design, and you have my vote! :D

    2 replies

    Hi Monkey Penny! I have a bag of everything ready to go for my latest project. I litteraly just grab it and go! Work out of it from home too, so always ready. In the main tote bag is a clear vinal, zippered case with the scissors and such. All other projects are each in their own tote. To change projects, just move the vinal case to the tote bagged project I want to take along. I leave each hook or needle in the tote with the yarn as each needs its own size. Hope this helps. Oh and it's so handy housekeeping wise too. Just pick up a tote and hide it anywhere any time folks visit. Quick as a wink! (They squash into the nifty-ist places.) Ha! ^_^, Tracy


    5 years ago on Introduction

    Ah...A Lady after my own heart! I'm only learning to knit and I also am learning Tunician Crochet. (Which uses a long hook.) Something like this would be So useful. Can you design covers for the tips of the knitting needles for me? (And a method for keeping them together, like earbuds, so the won't get lost so easily?) I find I can knit for only about 5 min. before my left hand starts to hurt, so having both along would be marvelous. I teach Crochet while waiting on Doctors Appointments. Everyone recognizes me and takes a quick lesson now and then. So fun.

    1 reply

    5 years ago on Introduction

    Interesting idea! Just want to say, when I got the newsletter with this post featured, I remembered a book on CD that my parents and I listened to once upon a time, where the murder weapon was cleverly stashed inside her knitting needles. This reminded me of that. But not in a bad way!

    1 reply