Lamp Prototyping Blog

Manufacturing 1 - Shade

Shade Manufacturing Plan:

This Diagram shows an in depth plan of the steps i will take to build and assemble the first part of the product.

The plan took a couple of drafts as I had to go back a few times to make changes. This is because i thought of problems that needed fixing throughout the planning of the manufacturing.

I will show each step through photos and talk about the each subsection, why it is necessary and the tools i used to complete the subsection.

Throughout the shade manufacturing section of this blog I will relate back to this diagram and it's specific points as a reference to what I am working on at the time.

Manufacturing Diary - Shade:

Manufacturing Diary - Shade - Main shade components (A):

A1 - CAD file for main shade 3D print:

This image shows the CAD file within Fusion 360 before it was sent to 3D print. This file was printed twice, one for the top and one for the bottom. It includes the 12 holes for the support beams at the bottom of the model and 12 half holes at the top to form the full holes with 2nd copy of the print. 

The 2nd copy is mirrored vertically on top of the first to form the full shade and they are held together by the support beams.

These parts are printed in a translucent white plastic to allow the light through. The circular shape allows for even distribution of the light from the LEDs and the properties of the material mean the light not only travels through the shade but there is a degree of reflectance within the lamp which means there is an effect which is reminiscent of the greenhouse effect of the light within the shade.

More images here

A2 - CAD file for holding rings 3D print:

These images show the middle holding ring (top) and the end holding rings (bottom) these all include 12 holes each, these holes correspond to the same place as the main shade (A1). The middle ring is in a quantity of 1 and the end ring in a quantity of 2, one for each end of the shade.

These rings are placed inside the main shade and are vital to the structural integrity of the whole shade as they are hubs for the support beams and add an inside support to the shades, which fights against any compression from the outside of the lamp.

These parts are printed in opaque black plastic. This plastic is common and cost effective, hence my use of it instead of another material. I originally thought the ring's opacity would affect the amount of light escaping the lamp but after further analysis of the shape of the lamp I found that it shouldn't be an issue due to the reflectance and the light exit angles of the main shade parts.

More images here

A3 - CAD file for holding rings 3D print:

This image shows one of the 3D print parts and some of the tools i used to clean it. 3D prints often come out with some remaining mesh around the edges and any overhangs. Due to the holes through the 3D printed parts there was a fair bit of mesh coming down. To remove this mesh i used a 5mm drill to clear the 5mm holes, a scalpel and an assortment of files. 

The mesh is done automatically by the 3D printed to support the next layer that it is going to print. It is a very useful solution to the problem which takes a small amount of time to fix and clean. Cleaning these parts thoroughly of the mesh is important to make them fit together perfectly as the print files sent in have very little fitting tolerance.

More images here

A4 - Fit Magnets to base holding ring:

Using a rotary table under a drilling mill (left image) i was able to cut each hole in the ring at 30 degree angles, this makes 12 holes for 12 magnets. These holes are 2mm deep and at a 10mm diameter to fit the magnets perfectly. I then used a 2 part epoxy glue to fix the magnets in place in the holding ring (right image). These magnets will be rotated around the center of the ring with a mirrored rotation plate below the top of the base, which is rotated by a pulley system. The rotation of the holding ring will translate into rotation of the shade and the support bars, achieving the movement i was aiming for.

More images here

A5 - Assemble parts:

After cleaning the printed parts i simply slid the holding rings inside the shade parts, due to the low fit tolerance i was able to lift up the whole thing once the parts were fitted. The printed parts fit very well and supported eachother enough to stand ,however i still went on to build the support bars as they added the aesthetic i was looking for and to add some more structure to the lamp in case it was knocked over or had impact that otherwise may have dislodged the parts.

More images here

Manufacturing Diary - Shade - Steel support bars (B) :

B1 - Cut steel bar to lengths needed: 

This image shows the bars cut down to the length needed. I cut the bars slightly over what was needed as it was important for them to reach to top and the bottom but it didn't matter if they overran a small amount. The bars are made from 5mm diameter bright steel, which is characterised by its resistance for compression and impact force, this was perfect for what i had in mind as the supports act as an exoskeleton to the more fragile 3D printed parts which form the shade. I had excess steel bar after cutting the 12 I needed for supports, this spare bar would become the middle section supports which are brazed on later in the manufacturing.

B2 - Design Jig to bend bars accurately:

This Engineering drawing shows a Jig I designed to hold the bar in place and bend it correctly. It also allows me to mark the bar where I needed to braze on the middle section supports later. This jig allowed me bend the bar to the right shape in the ends and make fine tunes to the rolling curve as it is not always perfectly accurately. 

I went on to build the jig using a wood peices under a drilling mill and a series of hardened steel dowel pins to act as the guiding pegs.

More images here

B3 - Roll bars into correct curve: 

Using a bar roller and a reference curve of the right diameter I bent each section of bar as close to the curve as i could. This method is one of the best methods for getting a consistent curve in a metal bar, however there is some correction needed as you have to put a reference curve next to it and do it by eye. After getting the curves as close as i could i brought the bars into the jig (B2) to do some final corrections and set them up for the next step.

More images here

B4 - Bend bars back at 90 degree angle 

In order to have the bars connect in after the concave curve, i had to accurately bend the ends of the bars back in towards the shade, where the bars go through the shade and are fixed in the holding rings. 

I did this using a mallet when the bar was in the jig to accurately fit the profile that i was looking for, when the bar corner was bent enough i could put the second end block back on the jig to check it's accuracy and make any fine tune changes.

More images here

B5 - Cut 3/4s of the bars short

After forming the bars main shape i cut 8 of them short at different lengths, this was to make them look more organic and so some of them wouldn't reach the top, this is the aesthetic that i have been trying to get from the ideation stage. After cutting the bars short i de-burred and sanded the ends to make them smooth instead of sharp, as this could be a safety issue to the user.

More images here

B6 - Braze middle support to bars

Now that the bar shapes and lengths were correct and ready, I used the spare bar and a brazing kit to join middle level supports in the places on the bars where they were required. 

This was my first attempt at brazing so i didn't get the cleanest joints but the tests i did held to a good enough standard so i decided it was the process i wanted to use.

B7 - Clean heat damage from joints

As brazing is a process that joins through heat and melting, it damages the steel and discolours it as you can see in the image on the left. This can be remedied with some sandpaper to sand off the damaged layer. I learned quickly to sand the joint carefully as if you sand it too hard the joint can fail and the middle support fell off, needing to be brazed again. The sandpaper works very well and the steel was restored to its previous reflectiveness without too much work.

B8 - Deburr bar ends

Before I fit the bars to the shade i Deburred the bar ends again just to make sure there were no sharp parts left on them, this is so that they fit perfectly in the holes and for the user's safety.

I used a belt sander and sandpaper to do this and to create a small dull cone on the end of the bars to give the end some sort of aesthetic rather than ending abruptly.

B9 - Fit the bars into the shade

Finally to complete the shade section i simply had to insert the bars into the shade. This sounds like a very easy task however i found that i had to make constant corrections to the bars as the smallest imperfection would stop the bar fitting into all 3 holes at the same time. Eventually i fit all of them in and i am very happy with the final product. I fixed them with superglue although If i did it again i would use a mechanical fastener.

More images here

References:

Ref 1 - Bernzomatic - How to Braze Metal With a Torch (2024) [Online] available at: https://www.bernzomatic.com/Projects/Fix/Braze-Metal