Create Mesmerizing Drawings on a Stand Mixer!

When I came across the Cooking Contraptions Contest I immediately got excited and wanted to make something fun out of a "boring" everyday item. I was asking myself: which kitchen appliance can I use in a safe, fun way? I didn't want to mess with AC power, heat elements or sharp objects.

The stand mixer was the perfect choice! It has a front (and sometimes top) hub designed for modularity and add-ons. I decided I want to attach something to the stand mixer's front hub and use its easy mounting and variable speed, and after many ideas and experiments I made a gadget for drawing on paper coasters.

My gadget is inspired by Barton Dring's Polar Coaster and I highly recommend his blog full of cool machines and great explanations.

Tools:

1. 3D printer and some filament - I used standard PLA filament
2. Soldering iron -
3. Metric Allen wrenches
4. Metric Combination Wrenches
5. Hacksaw or any other tool to cut the brass standoff

OTS (off-the-shelf) Parts:

1. (1) 688zz Bearing (8mmID 16mmOD 5mmL)
2. (1) 15mm F-F M6 Hex Standoff - I bought an 80mm standoff and cut it to length
3. (1) DIN 7991 M6x40 (Hexagon socket countersunk head screw)
4. (2) DIN 7991 M3x10 (Hexagon socket countersunk head screw)
5. (2) M3 Heat set thread insert

1. 3.5" Paper Coasters

Optional:

1. Soldering iron tips for heat set inserts - I don't have these, so I just use a standard conical tip

I designed the T-Vault using Fusion 360 - Why?

1. Free for hobbyists
2. Easy to use without extensive CAD experience
3. There's a built-in McMaster-Carr interface which makes working with COTS hardware so simple
4. There are tons of plugins and add-ons available
5. Creating illustrations and animations (like the ones in this Instructable) is very simple

The 1st task was to take measurements from the hub itself and create a 3D model. For my purpose I only needed the inside part of the hub, so I created 1 component for the drive socket and another component for the plastic housing, the screws were added mainly for aesthetics.

Next, I needed to design the part that will lock into place inside of the hub. This stand mixer (made by Kenwood) utilizes a quarter-turn bayonet, so I designed a part that can be inserted into the hub and then rotated to lock. It took some trial and error but after a couple of tests my bayonet was done.

After I had the hub itself and the bayonet mechanism, I could basically attach anything I wanted to the stand mixer, in the attached section you can see how the parts are stacked to allow for rotation without axial movement.

For the coaster Holder itself I have remixed Barton Dring's design.

I printed all parts using my default setting:

1. 3 walls/perimeters
2. 20% infill
3. Brim
4. No supports
5. You can see the suggested print orientation in the attached image
6. 
   

There are 5 files, print 1 of each:

Using a soldering iron, install (2) M3 heat set threaded inserts into the bayonet.

1. Place the insert above the holes and gently press them in until the smooth part enters the hole
2. Make sure the insert is perpendicular to the surface, otherwise it will be difficult to fix it later on
3. Let the soldering iron heat up, if you have an adjustable temperature soldering iron, I suggest ~230deg c.
4. Hold the soldering iron above the insert, try to align the tip with the internal thread
5. Slowly press the insert using the soldering iron until it is flush with the printed part's surface
6. Inspect the insert and make sure there is no molten plastic inside the thread
7. Repeat 4 times

When installing the inserts, try to be as perpendicular as possible

If you have designated tips for threaded inserts - use them! Otherwise, use a standard conical tip and make sure you clean it from any plastic residue after you are done.

Take a look at the exploded view above and assemble (it is pretty striaght-forward and there's not a lot of room for error). The only tools you'll need are 1.5mm & 4mm Allen wrenches and a 10mm Combination Wrench to tighten the screws.

Important! Only attach or detach while the stand mixer is turned off!

1. Take the assembled rotary gadget and gently insert it to the stand mixer's hub
2. Rotate to lock
3. Place a paper coaster, make sure the external teeth are holding it in place
4. Turn on the stand mixer, start with low speed and carefully adjust it
5. Use pens or markers to draw and make sure you don't apply too much pressure on the coaster holder