Dears, can the ‘3Star’ and ‘4Star’ lampshades be injection-molded?

Dear David,

What is the meaning of "3star" and "4star" exactly?

Excuse my ignorance.

My best regards,

Dear Raul,

thank you for your message. The '3Star' and '4Star' lampshades are single component designs.

Hello David,

Well, i fully understood the application! Beautiful designs and different to the current designs.

To be honest, is not an easy application but before of we can say if it is possible or not, there are some considerations to take into account. As a thickness, length, temperature exposure, flexibility...

Perhaps the injection molding is not the best way to make this product.

But if you're interested, could attempt to study the options in the market and investigate options.

Best regards,

Raül.

Hi, David,
Great designs and 3star can be made by injection molding, but 4 star I am not very sure

Hi David,

Great designs indeed. I would like to add some comments on the idea to produce these parts by injection molding.

First of all you have to realise that due to the design the parts when injection molded will have a large amount of weld lines and that due to the location of these weld lines it may prove to be difficult to provide sufficient venting of the mold. This may lead to aesthetic and structural issues in your final application.
In your design you will bend the molded part to arrive at the final shape; it is important to find out the occurrence of local high stresses and maybe eliminate these. It will be important to use sufficient radii in corners etc.
From your message I gather that you have already tried to produce parts by using sheet and a secondary operation like milling to produce parts. Have you tried to assemble these in the final parts to establish whether your material of choice is the right one?

Regards,
Jan

Dear Jan,

thank you for your message and explanations!

Lexan, Makrofol and Kydex are the right materials
(even for hot 100W incandescent globe light bulbs -
which are sadly being phased out...).

The relatively high cost of these sheets and also
of their processing, has made me wonder about
injection molding.

I reckon it might only work (if at all) at a very large
production scale (?).

Best regards,

David

DH product design

Hi David,

Generally injection molding is indeed more suited for higher production numbers due to the cost of mold manufacturing and other production cost. However, from what I understand from your description this application is aimed at the more exclusive, higher end of the lighting market where the end product would be sold at a higher price than let's say production cost and a reasonable margin? You could therefore investigate whether you have the margin to implement injection molding as the manufacturing process.
Regarding the tool design, have an expert look at this as at the given geometry looks quite simple but the wall thickness of the part (1 mm.) could be a challenge.

Good luck,

Jan

Hi Raül,

thank you for your message!

The '3Star' and '4Star' lampshades are made from 1 - 1.5mm thick polymer sheet.

I have used Lexan, Makrofol and Kydex as they are high quality products with good heat and UV resistance.

The '3Star' is basically a triangle with many cuts. Each side of this triangle is 660mm long.

Die-cutting 1mm polycarbonate (the '3Star' has ca. 15 meters of cuts) proves to be difficult.

Laser-cutting 'burns' the material (turns the edges of the cuts brown).

A water-jet tears the material in a rather rough way.

An oscillating blade struggles to do the more narrow curves of the cuts towards the three corners of the '3Star' triangle.

Milling works quite well, but is slow and therefore expensive.

Your advice will be much appreciated.

Best regards,

David

DH product design

Hi Jan,

thank you!

This application was originally aimed at the non-exclusive end of the lighting market.

Its geometry seems simple: a triangle cut from ca. 1-2mm thin translucent sheet material.

Sadly, the number of cuts within this triangle appears to be too high...

Best regards,

David

DH product design