How to launch your electronic device into “series” and not be left without pants
Spoiler for 2024 according to the cost of work (approximate prices)
Printed circuit board (PCB)
Circuit design (selection, test sample) – 150 thousand rubles.
Tracing and wiring of 2-layer PCB for the case – 100 thousand rubles
Order 5 test samples with assembly at JLCPCB \ Resonite – 50 thousand rubles.
Development and debugging of software for MK – 150 thousand rubles.
Testing, identifying shortcomings, reworking, improving functionality – 50 thousand rubles.
5 more test samples with new edits – 50 thousand rubles.
Lot of 100 pcs. with assembly in China (individually depending on the number and price of elements, PCB size, but 4 times cheaper than in the Russian Federation) – 200 thousand rubles.
TOTAL: 750 thousand rubles.
Frame
Design
Development of housing design – 250 thousand rubles.
Preparation of a 3D model for plastic casting – 250 thousand rubles.
Device renderings (10 pcs.) – 50 thousand rubles.
Edits and improvements – 50 thousand rubles.
Production
Molds in China made of steel (500 thousand rubles per housing element on average) – 1,500 thousand rubles. (50% advance)
Molds in the Russian Federation made of steel (800 thousand rubles per element)
Molds in the Russian Federation made of aluminum for simple parts (150 thousand rubles per element)
Batch of cases 1000 pcs. – 200 thousand rubles.
TOTAL: 600 + 1,700 = 2,200 thousand rubles.
TOTAL: 2,950 thousand rubles.
How it was with us
Once upon a time, during the cold winter season, foreign manufacturers of controllers and expansion modules (Siemenes, Carel, Schneider Electric, Danfoss, WAGO…) left the ICS market. We wandered around and around, tried to switch to Zentec, then ARIES and EKF, suffered greatly, and decided to start developing our own controllers to suit our needs.
Would you say that you decided to invent a “bicycle”?! No, we just made our own.
It is better to constantly improve your product than to use a good one, but someone else’s.
Analyzed the market, determined the niche and demand for the product
Competitors' proposals analyzed in detail
We identified the best solutions and added their advantages
Started development
Circuit design, software and PCB test samples
If you yourself do not have experience in circuit design, then it is better to turn to specialists in this matter.
We draw up a detailed technical specification for the development of the device, where we describe:
Number of inputs/outputs
Types of measured quantities and measurement accuracy
Supported Interfaces
The need for isolation/decoupling
Supply voltage and connection type
Microcontroller manufacturer and family
Location of inputs/outputs relative to the board
Type and size of connection connectors
Approximate PCB Dimensions
We describe the method and places of fastening the board to the case (latches \ grooves \ screws)
The need to manually solder a couple of test samples
Writing MK firmware to check circuitry
Software in which development will be carried out
I recommend using the web version of EasyEDA Pro. You can add developers and control the process, make edits, there are 3D models, simulation and checks. Upon completion of work in it, order test boards at JLCPCB, or export BOM, Gerber, Pick and order from any other place.
We are looking for a performer on FL, Avito, thematic forums, and preferably in TG channels for circuit design
We send him the technical specifications and ask him to send him your portfolio and tell him about the implementation of similar projects
Select a couple of proposals you like, discuss the cost and deadline
Break down the payment into stages of work and start development
If the circuit designer is excellent, but the microcontroller you need does not know how to program, then at the same time we are looking for a software developer for test firmware.
The task of the test firmware is to launch the MK and make sure that the inputs/outputs are working correctly. It often happens that during the testing process some circuit design solutions have to be redone.
You can contact specialized companies, which will be much more expensive, but on a turnkey basis.
Screenshots of a simple project in EasyEDA
A month later the circuit design was developed. Test sample for a couple of days soldered and tested for a week. You can go to rethinking how to remake it all development of the case.
Development of the device case
For our purposes, we need a durable plastic case that does not support combustion, with the ability to be mounted on a DIN rail. The high fluidity of plastic allows the implementation of almost any design, as well as rapid mass production of the desired color.
The development of the case can be divided into:
Design
Prototype
Model for mass production
We select several of our favorite cases from competitors, and also describe and attach screenshots of what design solutions we would like to use.
In our case, the device is mounted in a control cabinet on a DIN rail and is sometimes covered with a plastic plastron, so we focus on the housing Gainta D3MGfor example. On the manufacturer's website there is a 3D model of the case in .step format, which you can try on your board for a better understanding of your design.
I enjoyed working in Shapr3D. We exported a 3D model of the board in .step format from EasyEDA, threw it into Shapr3D along with the case model and let’s customize it.
Oddly enough, we again draw up a detailed Technical Specification for the development of the case and indicate:
Case dimensions
Screenshots of your favorite solutions (not necessarily in plastic cases)
Attaching a 3D model of the printed circuit board
Places and type of fastening of the printed circuit board to the case
Method of connecting body parts to each other
Location of light guides and technological holes
Color of materials, location of ventilation holes, wall thickness
The 3D model of the body must be transferred in its original editable form
Discuss the possibility of printing a couple of prototypes on a 3D printer (preferably powder)
After drawing up the technical specifications, we begin to implement it
We are looking for an industrial designer (a couple of links at the end of the article)
We discuss the details with him
We break it down into stages and get to work
A month later we receive sketches of design options, agree on the one we like and make additions/edits.
More photos
We agree on the size and location of light guides and technological / ventilation holes.
We get the first sketches of the case and try it on the printed circuit board
We check the board installation locations, connectors, additional equipment and the general concept.
Renderings of the selected case design
After a thorough check in CAD, we print samples of the case on a regular 3D printer (or on a photopolymer printer, as in the photo below). We install printed circuit boards, check the fastening locations and the quality of assembly of the body parts together.
At this stage, we have received a 3D model of the body, but it is not yet suitable for casting.
Injection mold making
For injection molding, it is necessary to modify the resulting model:
Check thickness
Add slopes for better release of parts from the mold
Work out the fastenings and arrangement of elements
Add technological recesses (compensators) to prevent material deformation
A mold for a small batch (up to 50 thousand clamps) can be ordered from aluminum. It is easier to process, but the requirements for the part being manufactured will be different, since it is easy to crush thin partitions with high pressure.
If the body consists of complex parts with small parts – steel mold
Simple shape of parts and low accuracy – aluminum
Where can I order a mold?
You can first send a request to the companies from the link at the end of the article. Ask the price, find out the requirements and listen to comments.
Then look for what dates the exhibition will be held at the Expo Center in Moscow Rosmould & 3D-TECH and planning a trip. Usually this is mid-June. In 2025 it will take place from June 17 to 19.
Take with you your sample case, a bag for brochures and come to the exhibition
Go to all Chinese stands and show your case, collect contacts
After the exhibition, you send a 3D model and collect commercial proposals (invoice) from them. It is advisable that they already have experience in manufacturing plastic cases for electronics and the quality that would suit you.
Open an account with VTB in yuan and pay an advance of 50%
Engineers from production will begin to send comments to the model and options for their solution
After discussing all questions and comments, production will begin for a couple of months.
They will make the first samples and send photos and videos; if everything is satisfactory, they will send them to you in a parcel for approval (usually 10 pieces)
Some (most) companies can also offer casting of body parts themselves, or they will send you a mold if you plan to cast in Russia.
Minimum order from 1,000 pcs.
When importing into Russia, it may be necessary to clear molds through customs, or to carry them through “cargo” in a roundabout way.
When the model is approved, mold modeling begins. Be sure to request the source code (3D model in editable form) upon completion of the work.
The mold has been manufactured, test samples have been received – mass production can begin.
Then device certification and congratulations. I hope everything works out for you.
Exhibition Rosmould & 3D-TECH takes place in Moscow in mid-June.
Exhibition ExpoElectronica takes place in Moscow in mid-April, where you should definitely visit to exchange business cards with Chinese and domestic electronics manufacturers.
Useful to read: Interface design for an industrial controller by Georgy Leftar or Case: how we made the controller housing.
There is also quite good sitewhere you can search for industrial designers and mold manufacturers in Russia.
