Wonderway Sn42/Bi58 T4 Lead Free Solder Paste No Clean, 138℃ Melting Point (30g)

Soldering is not something I am an expert at. This made repairing a ring quite simple. I found if remove the plunger and need and place the caps back on the syringe after use, the solder does not dry out. I have used it several times over the past month and it is still workable. The solder is quite versatile and a good product for the money.

Excellent stuff, good value as not very much is needed and pretty easy to use or clean up. I bought this to assist with removing solder on controller pcb's so that I could do stick swaps. I do not use this for the solder to hold the new sticks in place I use 63-37. What I use this for is to add a little to the globs of factory solder to help reduce the melting point as most use non leaded these days. If you are doing it for this purpose you do not need very much a small dot and you are good. Then just a touch of heat to melt the solders together and then remove, very easy and works great.

This solder worked really well for my projects. It melts smoothly and flowed nicely, which made my joints clean and easy to solder. I also like that it’s lead-free — it gives me extra peace of mind when working in shared spaces. The thickness (Sn42/Bi58) felt just right for both small and medium-sized connections. Overall, I’m very happy with this solder and would buy it again.

The low 138C melting point is genuinely useful for soldering heat-sensitive components. I have used this on several PCB rework jobs where I could not risk overheating nearby parts. The paste flows cleanly and produces bright, shiny joints without much residue. The no-clean formula means you can leave it in place without worrying about corrosion. The T4 grind is a good size for most SMD work. One tip: replace the plunger cap after each use to keep the paste from drying out. Overall a quality solder paste at a fair price.

Works well, melts easily under hot air or on a hot plate, but it is EXTREMELY hard to get out of the syringe. It comes with standard leur lock hollow needles, which are way too thin for the thickness of the paste. Ended up switching the needle to a larger one, and it is still very hard to get out. Other than that, it works perfectly.

Weirdly, this is some of the best flux I’ve ever used. Easy to clean, no black residue, smells acceptable, and solder flows like water. This is my go to stuff.

I’ve been using the Wonderway Sn42/Bi58 T4 lead-free solder paste, and it’s easily one of the best budget-friendly pastes I’ve tried. The 138°C low melting point makes it perfect for delicate components, SMD soldering, and rework projects. It flows evenly, wets the pads nicely, and leaves very little residue — the no-clean formula really lives up to its name.

Works as advertised

Worked great, the low melt temp really makes it easy to work with using hot air. Got some excellent solder joints with low effort on even the smallest SMD components i was testing with. It is fumes and mess free for zero cleanup and you don't need much at all to get a good solder joint. Very impressed and glad i went with this one.

Much of the new electronics now ships with lead free solder which works great but is less forgiving to thermal expansion and contractions over time and may require reflowing a component. This is perfect for the task as it makes the hobbyist capable of almost pro like repairs. The paste solder flux applies very easily with the syringe (make sure you recap it tightly) and is best flowed with a hot air solder gun. It will make clean repairs (maybe as not as easy as the video's), it is always good to keep a little bit of solder wick on hand for a clean job if you get too carried away. Do a bit of practice on scrap boards with components until you get the knack! I highly recommend this with a tube of 37 tin 63 lead and you are set for most repairs.

Needed the for lead free desoldering. It works great and does what it says it supposed to to do. Solder my issues I was having prior to purchasing.

Help to avoid soldering bridge. Good

Best low temp solder paste I ever had. I am going through a lot for manual prototyping. This one here flows absolutely perfectly, the flux evaporates completely, and no solder balling at all. Same quality of joints as with industrial high-temp reflow process. Amazing! My worst nightmare was Chipquick NC191LTA10, sold by Digikey. Extreme solder balling effect regardless the temperature profile, gooey residue that can't even be washed off with 99% alcohol.