Timeless Resin Lamp

It's late in the day in school and my then girlfriend's birthday was due in 3 days time. It has been always been a custom for me to make things for my girlfriend as an expression for my dedication. I made this lamp 4 years ago when I was a student. Funnily enough, I had recorded the steps making this.

The year was 2017. It was the final year before I leave university. I knew I had to make the most epic present ever. Well to me that is. After pondering on the research lab's foam ball-filled chair, I decided to make a resin lamp out of recycled wood for her. This will be my first time casting and would sum up the machining skills that I've picked up that year too. The design intent is to have a minimalistic yet beautiful wooden lit base with the resin as a modular piece where one could swap to different shapes.

Without further ado, let's begin this love story- The Resin Lamp.

Total Dimensions: 90mm x 90mm x 300mm (Including Lamp Head).

Structural Materials

1. 1 x Random Recycled Wood
2. 1 x Finishing Wax
3. 1 x 3mm Acrylic Sheet
4. 1 x Super Glue
5. 1 x Wood Glue
6. 1 x Buffing Machine
7. 1 x Different Grit Sandpaper
8. 4 x M3 Wood Screws

Electronics

1. 1 x 1m Power Supply Wire (240V@13A)
2. 1 x 12V Light Source
3. 1 x 12V LED Driver

Others

1. 3000 x (Loving heart + Patience)

For starters, I randomly chanced upon a beautiful squared wood lying around in the lab near the recycling bin. We typically recycle raw materials there. Although slightly damp-looking, I could feel the weight and quality of the wood. Frankly speaking, I was not certain whether it was rotten internally but I decided to take a chance. The surface felt dry too so I decided to give it a go.

As time was tight, I did most of the details on the fly during machining. Nonetheless, a quick CAD of the rough sizes of the light source, raw material and the layers were made in Rhino. From top to bottom, the layers will be as follows:

1. Resin Piece: A cube-like structure to be cast.
2. Acrylic Base: Shape that locates the resin onto the wooden base.
3. Light Source: A squared light source that makes the light-magic.
4. Wooden Base: To hold up the resin piece, accommodates wiring and part of the visual feature.

Machining the Wooden Base is split into 4 sub-steps:

Step 1: Cutting Down to Size

• Mark using a pencil to the right length of 185mm
• Using a vertical band saw rough-cut the raw material slab to length
• You can trim this down to the right height using a mill (but accuracy doesn't matter here)

Step 2: Finishing the Surface

I would like to retain as much of the original dimension, so major faces of the raw material just needs some finishing to remove the dirt and "damp"-looking surfaces (i.e. darker surface) to reveal its inner beauty.

• Using a face mill, mill off the surfaces of the raw material
• To create an accurate dimension, I rough mill flat all the faces
• Measuring the final dimensions after, I offset the dimensions accordingly
• At the end, you will reveal a dry and light faced wood that is 90mm x 90mm x 185mm.

Step 3: Pocketing for Light + Acrylic Interface

• Using an end mill, I recessed the wooden face to the depth of the light source
• Fortunately for me, the light source is a simple square
• To aid in the removal of the light source for servicing, I create through-holes on 4 corners
• Lastly, I made another pocket to fit the acrylic face

Step 4: Housing for Wiring + Driver

For wirings, we have to create housings to contain the driver as well as create a wire route from the driver all the to the light source. Other considerations include how one would want to create strain relief for the wires. Here's what I did.

• Pocket a large hole at the back that is deeper than the thickness of the driver to contain it while having the part sit flush on the underside of the wood to the table.
• Using the longest drill bit I could find, I drilled down through the wood on one side of the minor faces.
• As the length is only about 100mm long, I had to flip the part on the other side and reorientate to the same position to complete the long through-hole.
• Make sure to use a larger drill bit than the wires to account for concentricity errors from the first and second hole while remaining functional.
• On the side of the major face, I made a hole to allow for strain relief where the larger 240V wires could go through. This also helps with strain relief and constrains the big wires to make it product look like a single piece.

For the light source, it's a common configuration where we have the power socket, driver and then the LED itself. Fortunately, I've tested this LED, there is no need for a huge heat sink and it gives off a very pure white temperature and sufficient luminosity.

In Singapore, we run on 240V@50Hz, I believe you guys are able to easily source for alternatives in your country. Just amazon or aliexpress them. For those using 3-pin UK plugs like me, attached are some photos on connecting your wirings to the plug.

If possible, use a heat shrink on the ends to make your wires neat and be sure to insulate any exposed wires.I had some in my live wire if you notice. Opps.

(ps. I would like to thank my then research staff, YKP, who gave me this light source. He has now started his own company, Knoctify. Geez, time flies)

The base assembly was the fun part when all the features are in place.

I have mounted the driver in using wood screws and existing screw holes that come with the driver. For the wirings, I have routed the mains through the hole I have made then secure to its 3-pin plug. Lastly, for the light source, I have laser-cut an acrylic piece to protect its surface and screw them down using wood screws.

This allows greater serviceability.

Oh yes, make sure to finish off with wax to protect its surface.

(ps. Shoutout to TL and YS for the resource recommendations.)

Here comes the most exciting part. This is exciting because it is something I have never done before. Here are the steps.

1. Design/Estimate the dimensions of the plastic piece. For me, it takes the dimension of the wooden base for continuity reasons.
2. Create housing to cast the acrylic. Ensure that it's tight.
3. Read the mixing ratio of the casting formula. You will have a resin and hardener component.
4. Stir the mixture until even.
5. Leave the mixture to sit overnight.
6. Remove the mould to reveal the casted resin.
7. If your formula is right, it should leave you a clear resin.

As you can see from the photos, I screwed up. Haha. But it's alright, failures are learning opportunities. I did not create a good seal for the casting mould. I did it out of plywood and I assume the sheer vicosity of the mixture will prevent it from spilling out. I was wrong.

If your curing is uneven like mine, you will have a weak structure with tons of internal cracks. To my surprise, it looked pretty artistic. Oh, one of the parts chipped off too, adding to its abstractness. :)

If you're not a newbie like me, please skip this step. You do not want to look at it. Haha.

From my previous step, parts of the resin have chipped off due to uneven curing. Additionally, as my mould is made of plywood, some of the surface chips have stuck onto the mould. To repair this, I used the handy clear superglue (take note on "blooming"). After glueing everything together, I sent it to the sanding station.

Sanding steps:

1. Using sandpaper, sand with an increasing grit size.
2. You should see your part turning from matt to clear finishing.
3. After dry sanding, I use wet-sanding for the higher grit size.
4. Finish the sharp edges with a file and high grit sandpaper.
5. Buff the finished product to a glossed surface.

For aid in my sanding, I used a pneumatic sander. Even with that, I took hours sanding this piece. Finally, I glued on the acrylic interfacing base to the resin to prepare for assembly. This is a true test of patience.

(ps. I did some salvaging on the wooden base too).

Once everything is in place, pop the resin piece onto the wooden base and flip on the switch! Ta-da!

And with that, we have completed a basic introduction on a casted resin lighting piece. I am very satisfied with how it turned out. Internal reflections within the "flawed" casted resin brought new life into its greatness. To me, it looks like a crystal! Amazing!

If you find this Instructable useful, do LIKE and SHARE this post and I will be submitting it to a Lighting design challenge! Do also check out my Youtube channel for more interesting design and engineering stuff. As I do not have easy access to traditional machine tools, this may be my final medium-sized scale project. Nonetheless, it's one that will always cherish.