Introduction: Plywood Chandelier
Thank you for checking out my instructable. This is my first attempt at writing one of these so any feedback or questions you have, feel free to leave them in the comment section.
This project explores many of my interest including:
- Practical Design
- Digital Woodworking
- Electrical work, and
All supplies were obtained at a local hardwood store, so I assume that they're accessible to all who read this. The fabrication was done at a local maker space here in Vancouver, BC, Canada - shout out Makerlabs.
The result of this project is a dinning room light made out of plywood!
- 1- 24" PowerLED Light
- 2 - 3/8" D 7" L Galvanized Bolts (nuts and washers as well)
- 1 - 3/32" D 50' Wire Rope
- 2 - 3/8" Security Snaps
- 2 - 3/16" Quick Link Connections
- 2 - 1/4" Toggler Anchors
- 2 - 1/4" Eye Hooks
- 4 - 3/32 Aluminum Sleeves
- 4 - 1/4" Wire Rope Clips
- 1 - 3/8" Light Receptacle CrossBar
- 1 - 3/8" Light Receptacle Nipple and Locknut
- 1 - 18 AWG Electrical wire
- 1 - Electrical Screw Terminal Block
- 3/4" Baltic Birch Plywood (not pictured here, but will have some shots in the Fabrication section)
- Autodesk AutoCAD 2021
- Autodesk Fusion 360
- VCarve Professional CNC Software
- Palm Sander
- Screw Driver
- Wire Stripper
- Tin Snips
- Needle Nose Pliers
- ShopBot PRSAlpha 96x48
Step 1: Setup Test Circuit for Light
With every project I do, I like to test things out ahead of time as much as I can so that I can visualize what's going to happen during the installation. This test circuit here is a great example. It's not a very complicated circuit, but it helps to explain the basic electrical interactions in the circuit. I've left some popup information in the picture to help articulate the connections, but the basic idea is that the I connected a dimmer to a wall outlet and to the PowerLED to make sure the light would connect the way I expected and to make sure that the light would dim.
**Disclaimer** In the interest of full transparency, I've included all the connections and descriptions of the circuit. However, I am experienced with electrical devices and am taking this activity on at my own risk. Should you wish to build this same project, you will be taking on that risk and liability yourself.
Step 2: Light Design
In the same way I like to test out circuits before installing them, I also typically model the objects in some type of CAD software. I thought this project would be a great one to try things out using Autodesk's Fusion 360 for Hobbyist. It was a great way to iterate through the design. I played with all manner of dimensions, material thicknesses, and even different types of material all virtually. I've included the DXF and DWG files for what I ultimately ended up creating. In addition I've marked on each one of the screenshots so you can see the dimensions.
Main Component Dimensions:
- Material Thickness: 0.75"
- Side Boards: 37.4" x 4.5"
- Main Middle Boards: 32" x 2.4"
- Middle End Caps: 2.4" x 2.4"
It was my first time playing with Fusion 360 for a project that wasn't a guided tutorial, so I think there's still a lot of room to improve in the future. In general, this was the typical work flow I followed while in the application for this project:
Typical Drawing Steps:
- Select a component and create a sketch
- Define User Parameters as values in the sketch so that you can modify them on the fly
- Use timeline to edit features
- Complete sketch and extrude the feature
- Pro tip - try to make every element a component
There's all kinds of things you can do with Fusion and I'm really looking forward to playing with this in the future.
Step 3: CNC Fabrication
The moment of truth! This is where the rubber meets the road, or more accurately - where the wood meets the router bit. I took a 2' x 4' piece of Baltic Birch Plywood to my local maker's space to cut out the various boards that I designed in Fusion 360 on the CNC. Here's how I worked through this process of cutting them out:
Personal Protective Equipment:
- Safety Glasses
- Ear Plugs
- Mask (it's 2020 after all)
Loading Material and Initial Calibration of CNC:
- First things first - this is a shared tool, so I typically like to do a once over of the machine and inspect the bed for any metal/debris
- Place the plywood on the CNC
- Secure the wood to the CNC bed with a screw in each of the four corners of the material
- Secure CNC bit. For me, this was a Freud 04-108 1/4" Double Flute Straight Bit
- Set the X,Y and Zero the Z axis
- Turn on all the safety mechanisms, and
- Turn on dust collection
Machine Settings Using VCarve Pro:
- Set material depth (using calipers this turned out to be 0.77")
- Remove any offsets from the machine so that it starts at X=0, Y=0
- Adjust the feed rate. Freud has a great calculator tool for this that you can find in this link
- Define pocket cuts with appropriate depths (shown in the Fusion files)
- Because this is a straight bit, it's import to use a ramp on the pocket cuts
- Define Inside Profile cuts
- Define Outside Profile cuts
- For outside cuts, add some tabs (typically use 3 tabs for outside cuts)
- Define number of passes
- Save toolpath and import into ShopBot control software
Step 4: Parts Assembly
After all the parts were returned back to the apartment, the assembly process began.
- Sand components. All components were sanded with an 80 grit, then a 220 grit sandpaper. This was done mostly with the palm sander but some of the harder to reach spots were done by hand.
- Open up the bolt holes 1/16" more to allow the bolts to freely pass through the board.
- Glue the end caps to the middle center board. Clamp boards together.
- Glue the ceiling end cap together. Clamp boards together.
- Let glue dry for 25 minutes (none of the components that are glued are load bearing).
- Sand glued components again for 80 grit followed by 220 grit sandpaper.
- Attach the LED light to the middle center board.
- Connect the electrical connections of the LED light to the screw terminal.
- Pass the bolts through the side boards, place a washer between the wood and the bolt head, and tighten bolt with the nuts.
Pro Tip: If you don't have a work bench like me and you live in a residential apartment, something I like to work on is the insulation foam. It's great to cut/sand on without worrying about destroying the landlord's deck.
Step 5: Installation
We've tested the light circuit, digitally designed the light, cut out the parts using a CNC, and assembled the parts. Now it's time to install this light! There's basically three things that need to happen: remove the existing light fixture, add the new electrical connections, and mount the light support.
Remove the existing light fixture:
- Most important TURN OFF THE BREAKER FOR THE LIGHT CIRCUIT
- Remove the glass orb of the old light - remembering to be extra careful because of the sharp edges on the broken pieces.
- Remove the ceiling cap fixture.
- Remove the electrical connections.
- Return old light fixture to landlord.
Add new electrical connections:
- Replace the original crossbar with a 3/8" light receptacle crossbar.
- From the test circuit, we know that the blue wire connects to the white neutral wire and the brown wire connects to the black hot wire.
- Run the electrical wire through the light receptacle nipple and through the ceiling end cap.
- Secure the ceiling end cap using the light receptacle locknut.
- Ceiling end cap is completed!
- Keep the power off until you complete the next step!
Mounting the Light Support:
- It's worth mentioning, but the most important consideration here is to measure the distance of the table to try and find the center of the table. In our design we're going to have one anchor for each end of the light. We know the table is 77.6" x 31.7". Our light support from the bolt is 29.6" apart. That means we need to have each anchor 24" x 15.8" inset from the table. (for those curious how I knew that, the length needs to be subtracted by the light support length divided by 2 [(77.6"-29.6")/2 = 24"] and the width is simply just half way [31.7" / 2 ~= 15.8"]
- Once you've established the center, it's time to install the Toggler Anchors. For those who haven't worked with these before, these are my go to wall anchor when I don't have a stud. I need to drill a 1/2" hole in order to install them. I typically do this in 3 stages, starting at 1/8", moving to 5/16" and then ending with 1/2".
- After installing the anchor, I thread the 1/4" eye hook into the anchor and give it a couple of tugs to make sure it's secure before proceeding.
- Next I secure the light to the mounting wire. I connect the quick link hardware to the bolt side and the security snap to the ceiling/eye hook side. This was my first time using the wire rope clips, and they are probably least favourite part of this build. Basically you make a loop of wire around the connection to each attachment, take off the u-bolt of the wire rope clip, feed both ends of the wire through the wire rope clip, and finally tighten them as mush as you can.
- Last and most tedious step, finding the right height of the light and the electrical connection. Adjust up, down, right, left, grab a cold drink, and repeat a couple of times until your satisfied with the lights position.
Double check your connections and flip the breakers back on!
Step 6: Let There Be Light!
If you've made it to this step as well and you're also enjoying the fruits of your labor. We made a light! As I mentioned in the Intro, it's great to make something practical - especially since it's one that you're going to be using on a fairly regular basis. There's a lot of lessons I've taken away from this project and hope to incorporate them into projects going forward.
- We did what we said - we completed the testing, design, fabrication, assembly, and installation in only 3 days! While I generally like to be more prepared for projects, it is fun to experiment and rapidly design things.
- We tried something new - this was my first project using Fusion 360. I'm excited to learn this software platform more as it seems to have a TON of functionality.
Area of Improvement:
- My least favourite part of this light is the mounting connection I have. The wire rope clips are clunky and have a considerable amount of the bolt showing. If I had to do this again this is something I would look at changing.
- Not using Fusion 360 for the G-Code for the CNC. It would have been much more time efficient to have had the CNC instructions created at the same time as I was designing the product.
- Finally, it might have been a little more fun to make the lights "smart" by connecting an esp32 or esp8266 to have the light controlled by another mechanism, but maybe that's a good starting point for the next project.
Until then - thank you for reading and I'll see you in the next instructable.
Participated in the