About the manufacturing of PCBs (Printed Circuit Boards).

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2
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0answers
25 views

Why did my homemade PCB turn out like this?

I did a first experiment with the UV-lamp + Transparency + Presensitized-Board method. This was my (promising but unsatisfactory) result: What could have been the culprit? For the record, this is ...
3
votes
3answers
93 views

Solder Mask and Pad Area (SMD vs NSMD)

I have been trying to figure out the "right" way to size pads for surface mount components, and I have found some conflicting wisdom floating around the internets. Lets say I have this hypothetical ...
11
votes
4answers
558 views

PCB, pads with holes but with different nets on top and bottom sides

I need pads with holes in by PCB, but the top and bottom side of the pads need to have different nets i.e. the top and bottom sides must be isolated. Here is the picture Is this possible to fabricate ...
8
votes
2answers
1k views

What is the use of the golden like coat on this circuit?

The below PCB belongs to a wireless access point. Could anyone explain what are the golden-like part of the circuit that is indicated by the red circles(ish)? What material is it? What is the the ...
0
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0answers
29 views

In pin-through-hole, how much bigger should the hole be than the pin? [duplicate]

I've been etching circuits. So I ask: how much bigger should the hole be than the pins I intend to put them in?
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2answers
82 views

Lead solder toxicity after cooling?

Now I am sure that most people have read discussions on the possible hazards of handling solder and how your supposed to wash your hands after handling it. My question is, after soldering something, ...
0
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0answers
39 views

Multiple Layers per Page Printed on Altium Designer

I use Altium Designer for PCB design. Usually, before ordering prototypes with a better finish, I make my own boards at home, as many do. I'm playing with the Press-n-Peel sheets for the tonner ...
4
votes
2answers
139 views

Creating printed circuit boards (PCBs) which aren't flat

I would like to create a printed circuit board (PCB) which is not flat and which is not shaped into a square, but don't know how to proceed. Can Cadsoft Eagle create such a board? If so, how? What ...
2
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1answer
66 views

Is a ceramic heater good to use in an etching process?

I use Sodium Persulfate as an enchant at a maximum temperature of 50 C. My experience with glass heaters is that they break if they are not fully submerged or if they are removed while it is warm ...
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3answers
102 views

Creating with BGA

I have a project that I've begun to work on, it's sort of an embedded PC type project, with a iMx6 arm processor. However, since this is a (potentially) commercial venture, we can't use prebuilt ...
-1
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2answers
163 views

Making PCB with DVD Writer

Maybe sharing this idea after building a prototype would be much better. As many of you know, there is a technique to make a PCB with laser CNC. You spray a matte black paint onto PCB, and burn that ...
3
votes
1answer
205 views

What kind of PC board coating is this?

I recently came into possession of two large (approx. 3x4 ft) copper-clad fiberglass boards from a junk sale. These boards are consistent with typical printed circuit board material (thickness, ...
0
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0answers
39 views

Why is all my photoresist stripping?

I got presensitized positive boards from Injecterall, but I'm using Datak chemicals (positive developer and etchant). I used Datak boards before and the process was very smooth. This time, after ...
1
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2answers
58 views

Non-glass heating element for an etching tank

I have been using below glass heating element (the part name is ET20) on my etching tank. The problem is that the glass is too gentle that breaks very easy for many reasons, I already needed to ...
0
votes
1answer
70 views

PCB Trace Orientations [duplicate]

When inspecting a PCB earlier today it occurred to me that all traces you find on modern PCB's are confined to 45 degree increments with respect to the (typically square) board edges. What is the ...
3
votes
1answer
195 views

PCB design: the setting of the test point and the use of variable resistor

I am designing a PCB circuit and meeting two problems: My design includes a two-stage MFB band pass filter. To make sure the center frequency of the filters is the same, I need to add a variable ...
0
votes
2answers
80 views

Which layer of PCB is used to identify cut-out of individual boards within a panel?

Let's say I'm using a software like EagleCAD to create a panel with a few copies of a design (or even different designs). There is a "Dimension" layer (mapped to an Outline layer, e.g., GKO), but ...
1
vote
2answers
188 views

Is quality China manufacturing possible without being there? [closed]

I'm looking for some help with manufacturing in China with respect to PCB fabrication and assembly, plastic injection molding and metal forging/brushing. Common wisdom in our days is that one HAS to ...
1
vote
1answer
66 views

How many of these UV lamps do I need for PCB fab?

I want to build a PCB UV exposure unit. It will be in a wooden box, it will have lamps and a glass above them. Basic design. For the lamp drivers I will use the circuit from the neon lamps at home. ...
3
votes
1answer
106 views

How to choose PCB manufacturing technology/factory?

I have sent some PCB designs to factories for prototyping. The price, however, varies greatly. Some ask 200USD for a four-layer 5cm*10cm PCB prototyping. While some only ask for 50USD. I assume that ...
6
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4answers
2k views

Are acid traps real? (2014)

Some people online say that acute angles in trace routing will cause these problems: "Acid Trap" - PCB etchant gets stuck in the corner, and eats away too much, causing open circuit "Peelable" - ...
0
votes
1answer
55 views

adding limiter to reduce distortion in audio amp

I got this schematic from adafruit. But at high volumes, it exhibits distortion. A guy from Maxim Integrated referred to include a diode-resistor network(BAV99 and R-100 Ohm) b/w C22/C23 and R8/R9(to ...
7
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3answers
172 views

What rules and tips make automated assembly easy?

What rules and tips make automated assembly easy, rather than unnecessarily difficult or completely impossible? In particular, if I have a circuit board that works fine after hand assembly, some ...
5
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3answers
526 views

PCB fabrication vs PCB assembly

What is the difference between PCB fabrication and assembly? Some companies like Golden Phoenix list that based on the size of PCB, it outputs a quote. Mine was 2.1 x 1.6 inch. It outputted 29 pieces ...
21
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6answers
1k views

Is it better to route a pad to a trace, or a trace through a pad?

When routing a PCB, is it better to route a trace through a pad as in 1 below, or to route a pad to a trace as shown in ...
2
votes
3answers
507 views

What is a suitable temperature rise for PCB traces?

I'm designing a PCB for a 10A relay and am trying to determine what the trace width should be. According to this trace width calculator, the biggest factors in the width are copper thickness, ...
3
votes
3answers
218 views

How much clearance should you include in through-hole component holes? [duplicate]

Is there a general rule as to how much clearance you should add to through-hole components' holes to allow them to fit easily? For example, if I have a component with 1mm pin diameter, what should ...
1
vote
1answer
81 views

SMD component clearance limitations and guidelines?

I'm laying out a fairly compact PCB (first SMD design of this degree) and am concerned about how close some of my SMD components are getting. I've been unable to find any guidelines or advice online ...
4
votes
3answers
638 views

How to make final good looking prototype of our project?

The handmade projects we make contain a lot of loose wiring and are actually bad looking products. So what should I do to make my product look better and that we can actually sell directly to people? ...
9
votes
4answers
906 views

Why do PCBs always have an even number of layers?

Looking at many online PCB fabs, when spec'ing out a board and uploading your gerbers, often you select how many Layers your board should have. Invariably, the options are always multiples of two. ...
1
vote
1answer
82 views

Correcting printed PCB (add a via)

This board is a prototype for the project and is for testing. It is missing the soldermask and silkscreen layers, so correcting mistakes is very possible. The board was printed correctly, but somehow ...
0
votes
1answer
101 views

FR4 measurement tolerances

I am going to get a PCB produced, but was wondering how the FR4 thickness measurements work, i.e. how thick are 1.6 and 0.8 FR4, in millimeters, to a few decimal places?
1
vote
1answer
128 views

How can I quickly build PCB prototypes? [duplicate]

The development cycle of the company I work include building alfa prototypes, sometimes in breadboards, and beta prototypes in printed circuit board assembly. A considerable slice of the development ...
3
votes
1answer
180 views

What are the steps for a beginner to electronics to get custom PCBs made for a simple adapter?

I need to make an adapter between two 14-pin board-to-board connectors, one being a MicroMatch and the other being a JMC. What is the most straightforward way to get a PCB designed and ordered so ...
0
votes
1answer
143 views

gold finger plating needed on prototype board edge connector?

I am making a PCIe card and will be ordering prototypes. I know that in my production cards I should order hard gold plating on the edge connector. Can I skip this plating on my prototype cards to ...
2
votes
2answers
1k views

Altium Designer: How do I scale the output gerber file generated by Smart PDF into 1:1 ratio?

I'm trying to export a PCB layout PDF from Altium Designer 13.2.5. When my PCB design is open, I click Menu > File > Smart PDF... to open the PDF generation wizard. Throughout the wizard, I do the ...
0
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0answers
230 views

KiCad: Component outline on the soldering pad - will it disturb the soldering process?

Lots of KiCad's SMD components (including capacitors and resistors) print the component outlines over the solder pad. The pictures are shown below, please notice C25-27, R5-6 and D2-3 PCB design ...
1
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2answers
130 views

PCB - Why to use Iron chloride?

Soon, I'll try to create my own PCB with the iron chloride method. I watched a video on that and it seems quite "easy". The only thing that I don't understand is the need to put the PCB on the iron ...
2
votes
1answer
635 views

How to add Mouse Bites or V-Groove to PCB In Altium?

I know mouse bites are more used to snap off one of many of the same boards in a panelized array, but I'm hoping to put mouse bites to snap off part of the same board if that's possible. Is there ...
2
votes
3answers
156 views

Preventing corrosion of copper PCB tracks

I do DIY PCB with the following steps: ...
3
votes
1answer
115 views

Defining a flex bus in Eagle

How does one go about creating a board file for a board with both "normal" PCB material, and flex materal? I have a project where I want the PCB and a flex bus to be seamlessly joined, like: ...
28
votes
4answers
4k views

What is Copper Thieving and why use it?

On many boards I've seen, there are little copper dots used for the purpose of "Copper Thieving". They're small round copper dots connected to nothing and arranged in an array. Supposedly they're for ...
3
votes
2answers
141 views

Will MG Chemicals Positive Developer 418 Develop pre-sensitized circuit boards?

I'm trying to find a cheaper alternative to the Datak stuff ($18 for 4oz!), and I came across this (MG Chemicals 418). I'm wondering if it will work with the pre-sensitized Datak boards I'm using (ex ...
0
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0answers
66 views

.PCB view from protel 1.5

I have some .PCB files created through protel 1.5 and advanced pcb when I had win98. How could I see or convert my files now on Win8. Any suggestion?
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1answer
119 views

plated through hole file?

I'm designing a new product and my manufacturer can't continue with out a "plated through hole file". They say that I didn't put it in the gerber files. How do I generate this in ultiboard? Or any ...
4
votes
3answers
296 views

Is a 1.0 mm thickness for a 4-layer PCB recommended or even common?

I just learned from the websites of a couple of board manufacturers that they can go as low as 0.8mm on a 4-layer board. I think going to 1.0 mm (instead of my standard use of 1.6 mm) would be ...
1
vote
1answer
64 views

how to understand a positiveresist PCB developed enough

I have a positiveresist PCB that I exposed the board to UV to transfer a layout for 5 min. I use UV box that I bought from Mega UK. After that I put the board onto positive developer. As I did not ...
2
votes
0answers
87 views

How long does developer solution last within its bottle

Originally I was going to just use UV exposure method but the boards tend to be expensive. Now that I've invested in a laser printer I can do toner transfer which I find much much easier/ more ...
1
vote
1answer
74 views

layout transfer to epoxy resin via UV light

I have an epoxy resin PCB board, inkjet transparent film, photo resist developer (Natriumhydroxid), and UV box. I printed the circuit layout onto the transparent film and cleaned the PCB's surface. ...
0
votes
1answer
112 views

how to print a PCB layout for UV etching

I am new to UV etching. I have a 2 layer PCB layout that I prepared on Eagle Cad. I am confused what layer do I need to mirror? After printing the layout what side of the paper turns to the UV light ...