Mathmos Lava Lamp Bottle Stand and Cap

Mathmos are the original inventors of the lava lamp, and they still manufacture and sell them today, more than 60 years later. They also sell spare parts for all of their lamps, including replacement bottles, which are relatively economical. This Thing is a replacement stand and cap for the Mathmos bottles. Files are available for the larger Astro and the smaller Astrobaby bottles, and the Freecad source file is available if anyone wants to have a go at producing versions for the others, or tweaking the design in other ways. The designs were modelled on images of the original parts, but are not intended to be accurate replicas. The Astrobaby version was intentionally flared slightly to aid in heat dissipation. If you want to have a go at making a functional lamp, a bulb holder is also included. The Mathmos lamps use 35 W halogen downlight bulbs (with reflectors), which are available in 12 V (ac/dc) or 100 V/230 V ac versions, depending on your comfort level working with electricity. Note that the 12 V bulbs require 3 A in operation, more on startup, and cheap power supplies will probably not work. I did not have success with any of the notionally "3 A" supplies I tried, and had to resort to a bench power supply. The mains voltage bulbs are more straightforward. I found the setup to work best with the bulb located close to the bottom of the bottle, and the attachment screw can be used to adjust the height accordingly. It is important to be cautious of heat generation, and to carefully observe the lamp while operating in order to turn it off if the plastic is softening, before it melts. I had success, after several failed attempts, with ABS. A lower temperature plastic like PLA is unlikely to be suitable. The temperature sensitive parts are the bulb holder itself, which can be adequately insulated from the heat using a suitable metallic heatbreak as a standoff. Also the lamp stand may overheat near the lamp, particularly the narrower Astrobaby version. I had success preventing issues by insulating it using a kitchen foil liner. The cap should be fine, at least I never had any problems. See the photographs for examples of the implementation. Note that the lamps run hot in operation, like the originals -- this is how they work. Also be aware that the lamps take about an hour to warm up, so don't be too impatient (but do keep a careful eye on the plastic). Some examples of potentially suitable hardware components are the following ( AliExpress affiliate links): 35 W halogen downlight (GU10 for 230 V, MR16 for 12 V) OR 35 W halogen downlight (GU10 for 100 V) GU10 lamp holder with connection block OR MR16 lamp holder Lamp holder heat break (may require 2 x M3 bolts to attach to lamp holder) Lamp holder attachment screw Power lead connector Power lead (100 V/230 V) OR 12 V power supply capable of supplying > 3 A. 12 mm cable gland