![]() Unlike lead-free solder, lead solder does not have a shelf-life and is less prone to losing quality after prolonged exposure to oxygen. Also, lower working temperatures reduces the risk of damage to components and circuit board. The advantages of lead solder are that it has a lower melting point, which is sometimes preferable for hand working components. This means potentially better performance where space saving is a concern. Lead-free solder can offer better lead spacing, which makes it more suitable for high-density components where pitches are tight. However, lead-free solder also has potential production advantages. Lead-free solder is generally regarded as having a more positive environmental impact than leaded solder, and also as being safer for human use. "What are the differences between lead-free solder and leaded solder? When checking the composition of lead-free solders (I don't have any myself), I found the following in information about Multicore Lead-free solder on the RS web site. Possibly the reported unreliability is in part due to the progressive formation of the undesirable alpha allotrope if the mix isn't right. I wonder what proportion of other alloys need to be added to inhibit the formation of the alpha phase? The common lead free solders seem to consist of around 96% Tin. I wonder if this is a factor in the difficulty often experienced in soldering old NOS components such as solder tags? If the "tinned" finish is in fact pure tin rather than a tin-lead solder, the change to the alpha tin allotrope would not be beneficial. More interesting is the comment on Tin itself, which is apparently unstable at room temperature and prone to disintegrate into powder below 19° C. Gregory, Blackie & Son, 1949 revised reprint of the 1932 original) only deals briefly with Tin-Lead solder, but does have a drawing showing the behavior for different proportions. Then we solder together the "flat" subassemblies into a 3-D structure (using wooden templates).Not much on TV so I thought I would investigate solders.Ī charity shop purchase book on Metallurgy bought some years ago ("Metallurgy", E. When soldering, the tape discolors and sometimes chars in the few millimeters next to the solder joints, but keeps the pieces in place. To position the pieces to be soldered, we use either:ġ) Wooden templates: we machine these pieces out of hardwood profiles or plywood, or we glue together wooden profiles and plywood.Ģ) For some larger, simpler and "flat" subassemblies, we use a paper copy of the drawing of the part, fix it with adhesive tape at the four corners onto a flat Formica-laminated plywood, apply pieces of 2-mils polyester-film-based double-sided adhesive tape in the areas subject to soldering, and we install the pieces of metal. TEMPLATES AND JIGS TO ASSEMBLE PIECES TO BE SOLDERED ![]() Conventional Tin-Lead soldering works well (but OK, it needs a bit of the best from Milan ![]() The following links shows pictures of some H0-scale ladders and latticeworks that we produced over the years using the a.m. Templates must be built from heat-insulating materials (e.g. Mounting templates: ALWAYS use mounting/soldering templates or jigs when soldering hands cannot be trusted when working at precise tolerances. Any type of efficient flux contains some Zinc Chloride not much of a problem, but the residues of flux or flux paste must be cleaned away after soldering (that means: solvents, hot water and detergents, cotton buds and some elbow grease). Steel needs additional cleaning and, preferably, pickling with chemicals (sodium dithyonite, oxalic acid, etc). Brass is easier to "wet" with solder, but conducts heat away from the soldering spot (the risk is to de-solder contiguous soldered joints). If the hot temperature melt the solder already put on neighbourghs parts, you can use small wet tissue paper around the parts to be soldered, piece of aluminium bar next to the parts can also absorb the temperature.īest of all if you can use it, use a resistance soldering unit, this is the best to use to build brass models.įrom experience (see also other previous topics) - all the advices posted by the colleagues are correct.īoth brass and steel can be soldered with conventional Tin-Lead solder and flux. Use a clean solder iron tip don't be afraid to use a quiet powerful solder iron a quick touch to the parts to be soldered is enough If you follow these steps it's not really necessary to use flux or solder paste, but this help 1. wash the parts in a soupy hot detergent water.Ģ.polish or with fine sand paper clean the parts which need to soldered the parts must shine a bitģ.don' touch these clean parts with your fingers.Ĥ.build some jig in wood and use some piece of paint tape to keep the parts in placeĥ.fix the parts in the jig and look if everything is in the good placeĦ.tin the parts to be soldered with some solder
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