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 paste from my local electronics shop. I quickly figured out that adding a little isopropyl alcohol helps soften it enough to work "good enough" with this system. However, I have a few questions for people who have worked with these syringe-style solder paste dispensers for far longer than me:
Do manufacturers make different types of paste for syringe application vs stencil-and-squeegee application? The paste I bought from the local shop is by MG Chemicals, Sn63/Pb37, and comes in a syringe, so I assume it's the right kind for my needs.
What's a good ratio of alcohol to paste (assuming Sn63/Pb37)?
Once I mix the paste and alcohol in a separate container, what's a good technique to get the paste into one of the syringes without smearing it all over the inside wall? I've thought about pouring all of the paste into the dispensing syringe and adding alcohol on top of that, but I'm afraid stirring within the syringe won't mix the mixture homogeneously.
What's a good tip to use on the syringe? The dispenser I bought came with a large sample pack of various types (metal and plastic), but none worked great. The paste is too thick to fit through the metal ones and I find the opening of the plastic ones to be a little too large to be precise.