Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [solder-paste]

Solder paste is used to connect smd's to the lands on the pcb.

Solder paste is used to connect 's to the lands on the . It is composed by powdered metal suspended on a flux medium.

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Solder does not stick to tip of soldering iron?

Basic question here, but it's driving me insane! The solder does not seem to stick to the tip of my soldering iron. After the iron heats up, the tip appears black (sometimes on all sides and sometimes on one side), then either it doesn't melt the…
user13267
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Why are the same alloys solid in solder wire and liquid in solder paste?

Is there a chemical difference between alloys in solder wire and alloys solder paste that make solder wires solid and solder paste fluids? For instance, this solder wire and this solder paste both have the composition Sn96.5Ag3Cu0.5, but the wire is…
Ken Grimes
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Is it important to file a new soldering iron tip before tinning?

I bought a cheap soldering iron. After reading articles and watching videos, I learnt that cheap irons get their resistor burnt easily. And many a times the iron becomes black as soon as you start heating it and then it cannot be tinned. I am afraid…
user141242
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Solder Mask and Cream in Eagle

I've got this part specification for the Paste Mask excerpted from the datasheet: There's a lot of lingo in this short paragraph that I would like to better understand conceptually. Specifically I want to know how to implement the prescribed…
vicatcu
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Questions on mass-production soldering

Wave soldering I am trying to understand how wave soldering works. Unfortunately the Wikipedia article has has left me unsure about the process: Is the entire board with its components quasi-immersed in liquid solder while it passes through the…
ARF
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Solder paste storage

Solder paste should be stored in a refrigerator and it has an expiration date. But what exactly will go wrong when it is stored at a higher temperature or past its shelf life? From what I know, solder paste is generally small tin balls mixed in…
Jiří Maier
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Double-sided Assembly

I'm going to assemble a prototype PCB which have components on both sides. I have access to a reflow oven with profiling control, solder paste and stencils (from OSH-Park) In the reflow process for the second side, I expect that small components…
pazel1374
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Solder paste not wetting at all

I have an issue with solder paste, I would like to know its origin so I can fix the problem and solder by components properly. I use a lead free Sn42/Bi57.6/Ag0.4 solder paste, manufactured by ChipQuick. Here is the datasheet. The syringe I'm using…
MaximGi
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Soldering 0.5mm pitch ICs using stencil and reflow oven

I'm new to SMD soldering, and tried to assemble a couple of boards, using a reflow oven. I 'm using a stencil (Kapton - mylar) and so far it worked fine except for the LQFP48 devices (pitch 0.5mm). In this case, the pins are bridged (too much paste…
Gus Sabina
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Can aluminum solder paste be used in electronic circuits?

Is a paste like Solder-It Aluminum Solder Paste ALP-21 suited for electronics? Are there going to be any issues with the solder under constant current due to chemicals in the paste or something like that?
Konstantin Konstantinov
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How to clean solder stencils?

I have had great success in the past using the reflow soldering method, using a syringe and needle to apply the paste to the board. Since I found myself repeatedly making the same boards, I decided to purchase some stencils. I purchased a framed…
sa_leinad
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Preparing solder paste for syringe-style dispenser

I've been hand soldering SMD components for years and recently decided to buy a cheap solder paste dispenser hooked up to an air compressor. One of these with a 30cc syringe: I don't know much about about solder paste, so I picked up a syringe of…
Dan Laks
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Using a home oven for solder paste

I'm doing a project and I have a PCB which needs surface mount components attaching to it. One component has already been attached, and I have some 138deg solder paste in a syringe. This is possibly going to sound very stupid, but is it feasible to…
ram
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SMD solder now or later?

I'm soldering up some boards with smd parts, using a hot plate to reflow, and I'm (inevitably) realizing that I got some of the wrong parts. Now, is it better to leave the boards with smd components stuck on them (sitting in wet solder paste) until…
thenoviceoof
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How to avoid solder bridges between LGA-16 pads (paste applied manually)?

I made a breakout board for an LGA-16 part (LIS3DH) and two attempts at soldering failed with a solder bridge between two pads. Top view of the PCB: The land pattern was created according to ST's recommendations in TN0018: PCB land length = LGA…
Christoph
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