19 Jan How it’s made: IoT Integrated & Interactive Display Unit
This month’s sheet metal case study looks at an Internet of Things (IoT) unit we designed and manufactured for a kiosk printing solutions company. They were after several free-standing units that could house a Microsoft Surface Pro securely, as well as a bulky printer.
Here’s a snapshot of the final specifications for manufacturing…
- Two sheets of CR4 mild steel
- One sheet at 2000 x 1000mm in size at 1.2mm thick
- One sheet 2500 x 1250mm in size at 1.5mm thick
- Six Punching Tool Changes for CNC Punched parts
- Nine parts laser cut including plinth base, chute, printer brace and housing unit
- Extras included gas struts for the top unit and a ‘mouse’ hole for the leads and wiring
How it’s Made Stages and Processes
Due to our client’s location (London), it was imperative that we created accurate 3D visualisations first to agree on the design and shape of the unit, as well as virtually test that all the components would fit.
The unit had to be secure to withstand theft, stable to take the weight of a top-heavy set of electronics and be easily transported in two sections (top and bottom). Access was required to the printer to allow for ink cartridge changing and restocking of paper. All of this was considered and demonstrated in the visuals to the client.
2: CAD drawings
The next step was to break the proposed 3D visual into flat drawings so the CNC machines can interpret the design for cutting. The team also provide these drawings to the machine operator so they can check off all the parts, checking the quantity produced and dimensional checks.
3: Laser cutting the metal
The CAD drawings are realised into machine friendly code and passed to the CNC laser cutting machine which cuts out the required pieces of sheet metal.
4: Let the bending begin…
Next stage is for all the cut sheet metal pieces to be bent. Our press brake operator took each part in hand and bent them according to the CAD drawings, as well as using his expert knowledge to bend each in the correct order.
5: Before welding, part testing
Once the flush head studs and clinch nuts are inserted using are Pemserter 2000 into the metalwork, and before the seams are welded, we made sure to test everything, test fitting all the parts together and making sure that all the electrical components fit snugly.
The pieces then made their way to our welding bays. Here they are TIG welded along all the seams and joints to complete the unit’s top and bottom sections.
You can watch our short video of our welder TIG welding the lid edge seam.
7: Grinding the Welded Joints
After the sheet metal pieces were fabricated together, they’re off to the grinding and linishing department. This is where our head of the department ground and sanded each weld joint, removing any welding marks or blemishes perfecting the finish prior to paint.
You may wonder why we bother if the unit is going to be painted, right? Well, a smoother finish, with fewer imperfections allows for a higher quality powder coated finish. You can see the smooth edges created in our short video below.
8: Powder coating
Once the units are sanded, it was time for the powder coating team to paint each part, gloss white. The client chose white so they could brand up the unit with vinyl graphics as required.
9: Powder coating plugs
All the pre-inserted flush head studs are covered with special caps to keep them from being coated in paint. If they were not covered they would be coated in paint and as a result the machine threads would be fouled up making them useless.
10: To assembly…
Once all the metalwork had cooled from the painting plant, it was time to assemble the first unit to test all the elements fitted, and everything connects as planned.
Then the top section is fitted to the base plinth. The two plinths are designed to slot together with a tongue and groove design, then secured in place with large plastic screws that can be hand tightened. The unit is designed so that it can be assembled by someone without tools, hence the larger screw head designed for hand tightening.
Next is the fitting of the locking mechanism. With high value electronics various bolts and locks are put in place to protect the valuable assets.
Watch our time-lapse video of our team assembling the first unit.
11: Functional features
Two design features of this unit also include a ‘mouse hole’ like cut in the back panel of the plinth base. This is for the printer and tablet’s charger cable to feed through.
Likewise you’ll notice from the photo that the unit is raised off the ground. The unit has four threaded screw feet. This is to allow for uneven surfaces and accommodate unusual flooring to make the unit stable.
12: The final IoT display unit
From sheet metal to full glory: the Internet of Things Unit, with integrated display and printer.