Group order of printed circuit boards - myths and reality
I wanted to organize a community of amateur electronics engineers, collect board designs from them, combine them into group blanks and order them in production. The essence of the idea is obvious - due to the fact that the preparation of production is divided into all, we get decent savings. Even if you throw a small commission for the organization. I think that many electronic engineers were thinking about creating such a service.
Life cruelly taught me a lesson. In fact, the necessary minimum of restrictions to ensure tangible benefits turned out to be MUCH more than I expected. As a result, I didn’t succeed. Of course, we collected and launched one order. All financial calculations and technical details under the cut.
Who is it for?
I have a lot of non-profit just-for-fun projects and of course I am a Jedi of a laser iron, but still I even wanted to use “real” boards with a mask and metallization in such crafts. First of all, to organize such a service, I wanted it to be cheaper to order boards myself.
Secondly, my scheme could interest lovers who, like me, have nowhere to wait for funding. Hackspace, freelancers, circles and my students very enthusiastically supported the initiative.
Thirdly, such boards can be ordered to verify the design of the future module in hardware. I have ordered prototypes of commercial products more than once, putting out a substantial amount of money, despite the fact that I had to roll a couple of copies before a large batch was ordered.
I will not hide the fact that I was counting, if not on the commercial profit from the whole event, then at least to compensate for my labor.
I decided to produce a group blank only in five pieces. That is, customers had the opportunity to order boards in multiples of five only.
The technical specifications of the board are the same for everyone.
I chose the urgent production of circuit boards (about one week), but before that there is an unpredictable time for collecting the order. Looking ahead, I’ll say that it took a little less than three weeks to collect the first order.
To begin with, we decided on the technical characteristics of the board:
- two-layer PP
- minimum clearance - 0.24mm
- minimum conductor width - 0.24mm
- material thickness - 1.5mm
- foil thickness - 35 microns
- minimum hole - 0.6mm
- edge processing - milling
I compiled a table and sent it to manufacturers asking them to fill in the prices. The table summarized the options for the size of the board and the presence of a mask / silk screen. In response, I received various offers, but one of them was the most profitable. Here is the table with prices (in rubles):
|No mask and marking||1800||2200||2600|
|With mask, unlabeled||3200||3700||4300|
|With mask and marking||6000||6600||7200|
Prices gave me hope for the success of the enterprise. I chose the 200x200 option with a mask, no silkscreen printing and set to work.
To start, I created a group in contact. I will give a link to it at the end of the article when you understand that this is not an advertisement and I do not invite you to join it. In the group, I posted the TTX boards and information about the group order scheme.
I calculated the cost based on the area of the board - 1200 rubles / dm2. Not the total area of the five boards, but the area of the board in the project. This meant that, for example, five boards 50x50 in size would cost the customer 300 rubles! If you order yourself, you need to pay at least 700 rubles for the preparation. In other words, the prices were very pleasant.
It is easy to calculate what to collect for the production of a group order I wanted 4,600 rubles. My profit would be 4600-3700 overhead.
After a small PR campaign among my friends in contact, the community gained over a hundred subscribers and I began to collect the order. I must say that I agreed with the manufacturer to provide Gerber files. That is, all the preprocessing was to be done to me.
Once every few days I spent the evening working with other people's projects. By the way, for the preparation I chose Layout, since it is free and most fans use it. On the preparation of a group project, you can write a separate article. I felt like an enterprise technologist! A bunch of approvals, checks, calls - at first it was especially difficult. I had to constantly delve into the study of Sprint Layout, making boards, post all sorts of recommendations in the group.
As a result, I collected the first order. This is how the finished project looked at the first stage:
Thunder in the clear
Pleased as an elephant, I exported it all to gerber and sent it to the manufacturer. In response, I received an account in which there was ...
more than 11,000 rubles! I sat and drenched in a cold sweat! I simply did not expect such a blow of fate! I was 100% sure that everything was going great.
Having gathered my thoughts, I began to look for the source of the problem and it showed up immediately. It turned out that everything is simple - initially they gave me a price for one set! Of course, I said that they would need five pieces, but everything turned out the way it turned out.
I was offered cost optimization options, but, of course, not at times. All of the above instantly lost its meaning.
Fortunately, only six people participated in the entire order, of which five were my good friends. Coordinating actions, apologizing and looking for ways out of this situation was much easier.
First, those who needed a lot jumped from the order. Mine in this group board was about 30%. I was not ready to pay more than three thousand rubles for my part. In addition to me, another person refused to participate. As a result, four people remained.
The board has lost a lot of weight to 103x161mm. We sent the order to production in Resonit. The cost was 3200 rubles. Customers had to put up with a 30% increase in price and a four-fold increase in the term, because this cost corresponds to the usual production time.
The board has already been manufactured and given to not very happy customers:
In addition, I ordered a second group board. In my hobby projects I often use Arduino-compatible boards and I had to make various shields for them. Firstly, I adjusted several boards to a size of 57x47mm. This allowed us to separate the boards by scribing. Secondly, I refused the mask and ordered not five group boards, but four. Ordered by standard dates. I got a board with a size of 188x228 and it cost me about 1,500 rubles. That is, if you introduce additional, rather stringent restrictions, you can save, but the point is much less.
The group is dead. Do not go there and do not enter. Got a lot of interesting experience and even more hefty cones.
Anticipating advice on ordering boards in China, I’ll briefly answer - I will do so.
I take this opportunity to thank my former student who helped me. MandarinVP is the author of the first electro-league in Yekaterinburg. He took charge of delivering circuit boards to customers (they are all from Yekaterinburg). He is developing his on-board computer for an electric bike and was among the customers. This is the man who helped the guys from this post in Yekaterinburg .
UPD: By the way, about the Chinese.
While I was collecting the order, managers from China from manufacturing plants wrote me twice. Some of them offered a price of $ 597.65 for our fee, while others even more! Honestly and honestly it was - I even saved pdf'ki! I told them that Rezonit does this for $ 300, and you know what they said to that? WHAT YOU ARE NOT READY TO COMPETE WITH SUCH A REALLY VERY LOW COST MANUFACTURER! It was some kind of surrealism!
PS: I know perfectly well the services for manufacturing circuit boards in China which are MUCH cheaper. Apparently, the Chinese are different.