Intro: LED Chemistry Lamp
I decided to make this lamp after being unable to find any affordable alternatives available to buy. The Mathmos Air Switch Lamp is no longer available, and was expensive, and all other boutique options were insanely overpriced - some were £300! It is a lot of money to spend on a lamp.
So I decided to build one myself, with some fairly simple requirements:
- It must be mains powered
- It should have a frosted effect with diffuse light
- It shouldn't get too hot or use a lot of power
The attached photos show the results of the first lamp that I made, which now sits happily on my bedside table.
It is not particularly hard to make, but some experience with a soldering iron would help, as well as being able to wire a plug, and using common sense.
There is an optional step for creating a base using a lathe, which I appreciate is out of reach for many people, however there are alternatives for creating a base - if you think of any ways to better my design then please let me know, I'd like to see some collaboration and feedback :)
Step 1: Shopping List
- The first process is to acquire the necessary materials for the project. I have included the items that I used for my first lamp, but this can be customised to suit your needs. I have indicated some factors to keep in mind for each item to help you decide what you want to use.
- I used a 500ml Duran Flask, with a wide neck, they were around £6.00 each
- It is important to have a fairly wide neck to ensure that everything will fit inside
- My flask has a neck diameter of 55mm, you will need 40mm+ to allow for enough space
- Cork stoppers are fairly cheap, and I got these from Amazon (£3.00 + £1.99 p&p)
- Make sure the cork is the right size for your flask, get a tapered cork with a size range that will fit your flask
- Corks are available from many different vendors online, so you don't need to buy from Amazon. If you cant find a perfect fit, then go for a slightly larger size as they are easy to cut down with a craft knife
- I picked the warm white 7W bulb (£2.82, free postage)
- It is up to you which bulb you choose, just make sure the fitting is correct and the voltage rating is correct too
- I tested some other bulbs, and found that anything beyond 10W is too bright
- There are many different types of fittings available, I picked the G9 fitting because it is the slim
- The fitting will need to match the bulb that you have chosen
- For my lamp I used a G9 fitting which you can buy here
- This is the product I used, which isn't cheap but it worked well for me
- Its up to you how you choose to frost the glass, there are cheaper alternatives out there
- Cheap and cheerful, but did the job (£0.99)
- Standard 2-core electrical cable that is rated for mains use
- Available in many, many places online as well as hardware stores
- Standard mains plug, again these are common online and in hardware stores
- I actually found it really hard to get some tubing to go through the cork and support the cable
- In the end I took a slightly different route, and used the core of a tablet stylus I had
- You can buy a pack of 10 on eBay for £0.99
- Wood for the base - as many will not have access to a lathe to create the base, I'll leave this as optional, alternatives could include buying a round piece of wood to mount the lamp on, attaching rubber feet etc. I chose to add a base in order to increase the stability of the lamp as it was a little top heavy. Even cutting a triangular base would work and wouldn't look too bad. A final alternative would be to apply a rubbery surface to the bottom of the lamp, using the kind on material you find on table tennis bats. this would increase grip and reduce the chance of the lamp falling over.
Step 2: Tools & Eqipment
- Craft Knife
- Screwdriver (for wiring plug)
- Soldering Iron & Solder
- Ventilated area for spraying
- Surface to cut on
- Wire Cutters
- All purpose glue
Step 3: Preparing the Flask
- Clean the flask out with soapy water, rinse, then dry to avoid any streaks. Ensure the surfaces is clear of dust.
- Shake the frosting spray as directed on the can, and coat the inside of the flask, following the directions shown on the can. Try to get a uniform distribution over the inside of the flask. Make sure you use a well ventilated area!
- Allow the flask to dry, and repeat again on the inside for a second coat.
- Carry out steps 2-3 on the outside of the flask.
- Allow to dry overnight.
Step 4: Prepare the Wire & Fitting
- Remove the plastic parts from the stylus (as shown in the images)
- Ensure that your cable will fit through the tube
- Expose around 5mm of wire from each of the 2 cores of the cable, and remove an additional 20mm of outer shielding
- Tin the exposed ends with a blob of solder
- Push the tinned ends firmly into the fitting as shown in the image, this will secure them into the fitting
- Cut the cable at the other end, allowing for the full length desired (mine was around 2m)
- Wire the plug into this end, and test the socket my inserting the bulb
Step 5: Adding the Switch
- Choose a point to add the switch on the cable, this should be at least 50cm from the bulb
- Carefully cut around the outer layer of the cable to expose the two inner cores at this point. do the same 40mm further down, then remove this band entirely
Step 6: Preparing the Cork
- Check to see if the cork fits snugly into the neck of the flask, ideally it should get stuck when it is halfway into the neck of the flask
- If the cork is too wide, gently shave off pieces of cork around the smaller end using the craft knife until you get a snug fit
- Using a ruler, determine where the middle of the cork is, and use the aluminium tube to push through the cork. place something over the other end of the tube so that you don't damage your hands when doing so. It takes a little time, but you'll get there eventually.
- Once the cork has been penetrated (giggidy) mark the tube at the point that extends 30mm from the base of the cork, and use the hacksaw to cut it down.
- The tube should fit tightly within the cork, if it is loose then apply some glue to the outside before pushing it in and leave it to dry.
Step 7: Putting It Together
- You'll need to unwire the plug to pass the cable through the tube
- Push the cable through the bottom of the tube, and run it through until the bulb dangles mid way into the flask, or at your desired height. Don't put it too near to the top.
- If the wire feels like it will slip add a little glue to the outside when you do this to fix it into the tube.
- Push the cork down into the flask so that it feels firm. You do not want to glue the cork in place or you won't be able to replace the bulb
- Rewire the plug
- Add the switch as indicated in the next step
Step 8: OPTIONAL - Create a Base
There are many different ways of creating a base, so I have listed this step as optional.
The simplest way would be to attach some rubber feet, but make sure that the lamp is stable if you choose this option. The cable coming out of the top makes it more likely to topple, so you may want to use an adhesive cable clip at the back of the unit to stabilise it.
Another option is to apply a grippy rubber surface to the bottom, similar to what you find on table tennis bats. Cut to size and adhere using glue.
Finally, the option I took was to custom make a wooden base. I used pine, although other types of wood are easier to work with on the lathe. I have included some pictures of my lathe work to indicate how I made the base, essentially its just a disk that is larger than the base of the flask with a recessed middle for the flask to sit into. I also used sandpaper to smoothen the edges, and I waxed the wood to prevent it from rotting and to make it look a little nicer.