Karhedron Posted May 31, 2012 Share Posted May 31, 2012 Not quite sure whether this belongs here or in the electronics section but here goes. I am doing some basic soldering of wires to rails (and also rails to rails) for electrical power on my layout. It is a simple N gauge BLT with DC control but I am having trouble with solding. I heat the rails and and wires before applying the solder but it refuses to flow nicely. I just forms beads and sits on top of the rail or wire. The best I have been able to manage is to "wipe" the solder across the joints using the tip of the soldering iron. I have not done any soldering since my school days but my recollection from that was that solder would flow along the joints like a liquid provided it was heated properly. But I cannot get it to behave properly now. I am using an antex 18W soldering iron which should be sufficient for basic work. Is the solder itsef the problem? With 2 small boys around, I opted for lead-free solder, could this be why it is not working very well? Should I ditch it and go back to plain multicore solder? Any advice from more experienced electricians would be very welcome as I am going spare trying to get the basic electrics working reliably. Link to post Share on other sites More sharing options...
Guest Natalie Graham Posted May 31, 2012 Share Posted May 31, 2012 Very basic, but you are using flux? If there's nothing to encourage the solder to adhere to the parts then it will form blobs rather than flow. As the higher lead content solders generally flow the best this might be more pronounced with a lead free type. Personally I think I would stick with mulitcore for the electrical connections. It is what it is designed for. Link to post Share on other sites More sharing options...
gerrynick Posted May 31, 2012 Share Posted May 31, 2012 have you degreaed the rails where soldering is to be done ?Acetone is brilliant for this ( nail polish remover ), but, keep it clear of all plastics. Otherwise use a fibreglass brush ( wearing latex gloves to keep the fibres out of your skin ) Go forth and solder ! gerrynick Link to post Share on other sites More sharing options...
RMweb Gold The Stationmaster Posted May 31, 2012 RMweb Gold Share Posted May 31, 2012 As Natalie has said, some simple points - 1. I agree with her, it's best to use multicore solder for electrical work, BUT 2. You still need flux, and 3. You need some decent flux - recently with no other sources locally I had no choice but to buy a flux pen from Maplin. These might be great for work on circuit boards but next to useless for pre-tinning rail and connecting wire. 4. For a good solder joint you must pre-tin both pieces which are to be joined - apply flux to each surface separately then 'tin' that surface with solder - make the solder flows freely onto the surface you are tinning. Then when you bring the two pieces together and heat the joint with the soldering iron they should fuse together and any additional solder - if needed - will flow to both surfaces. I have always pre-tinned both connecting wire and track - and almost invariably no problem then in making the joint. Link to post Share on other sites More sharing options...
buffalo Posted May 31, 2012 Share Posted May 31, 2012 I assume this is nickel-silver rail? It's an electrical joint, so I always use a normal electrical multicore solder without any additional flux. Despite what some others say, I also find this works fine with steel rail, but maybe fifty years soldering experience helps a bit there. More importantly, avoid lead-free or low-lead types as they are much more difficult to work with, especially if you have limited soldering experience. To clean the bottom of the rails I just use a couple of strokes with a flat needle file on the base of the rail. There may be some corrosion/oxidation products that can't be removed by wiping with a solvent. I've not worked with smaller rail, but for code 75 I usually use a 25W Antex iron with 2mm screwdriver tip. The 18W may be a bit light for this unless you have a reasonably heavy tip that can retain sufficient heat while you make the joint. Nick Link to post Share on other sites More sharing options...
Kenton Posted May 31, 2012 Share Posted May 31, 2012 No one has mentioned one of the most important things: Tinning I heat the rails and and wires before applying the solder but it refuses to flow nicely. I just forms beads and sits on top of the rail or wire. The best I have been able to manage is to "wipe" the solder across the joints using the tip of the soldering iron. This may be also an issue. The best way to make an electrical join is to tin both components and then join the two tinned components. Remembering the most important thing is cleanliness of all parts, bring the multicore solder to touch the freshly stripped wire then apply heat from the iron. The iron should be hot enough that the solder melts immediately and will flow along the hot wire. I have never had to use additional flux and would NEVER use liquid flux or plumber's flux on electrical work. Then repeat with the new cleaned rail. clean the rail with a solvent, I use IPA as it doesn't dissolve sleepers, then with an abrasive, glass fibre pen or wet'n'dry paper, then same process a with the wire place solder to rail and then apply heat. Remember that the soldering iron tip should have been tinned before all this, it should be nice and shiny and definitely not black. Finally bring the tinned wire to the tinned rail simply applying heat should belt the solder and produce a join. Beware any movement or the parts as you remove the iron, or you will get a 'dry joint' (simply cured by reapplying heat and being more careful). [Ed] posted earlier but failed to display Link to post Share on other sites More sharing options...
buffalo Posted May 31, 2012 Share Posted May 31, 2012 No one has mentioned one of the most important things: Tinning... Mike did, so I didn't bother repeating it: ... 4. For a good solder joint you must pre-tin both pieces which are to be joined - apply flux to each surface separately then 'tin' that surface with solder - make the solder flows freely onto the surface you are tinning. Then when you bring the two pieces together and heat the joint with the soldering iron they should fuse together and any additional solder - if needed - will flow to both surfaces. I have always pre-tinned both connecting wire and track - and almost invariably no problem then in making the joint. Otherwise, I entirely agree with the rest of your post. Nick Link to post Share on other sites More sharing options...
Nigelcliffe Posted May 31, 2012 Share Posted May 31, 2012 I suspect that 18W and lead-free is not enough power to keep the temperature high enough. The problem with a low wattage soldering iron is that whilst the tip may be 300+ degrees in still air, as soon as it touches some metal the tip is being cooled dramatically. There is insufficient power behind the tip to hold the temperature through the solder to get a good flow along the metal. My solution would be a more powerful iron and to use traditional 60/40 lead/tin solder (standard lead based multi-core is usually 60/40 mix). If sticking with lead-free, then I think you need a significantly more powerful iron, and the right flux for the solder. Clean the rail immediately before application of solder or flux. If you have to do something else, then re-clean the rail. A fine file works (though not my first choice, its a bit coarse for this job), or small fine emery board (for polishing nails (the ones on your fingers, not the ones you hit with a hammer!!)), or a glass-fibre brush. As others have said, the "right flux" here is one you can clean up without requiring to dunk everything in a liquid tank. So, definitely not Powerflo (brilliant stuff for plumbing!) or phosphoric acid (good for etched kits!). For extra flow, solder with a small silver content in addition to the lead/tin mix. This flows extremely well, but I don't think that helps with electrical work. - Nigel Link to post Share on other sites More sharing options...
meil Posted May 31, 2012 Share Posted May 31, 2012 Don't use lead free solder. Get some 60/40 electrical solder - such as Rapid 85-0592 Link to post Share on other sites More sharing options...
Kenton Posted May 31, 2012 Share Posted May 31, 2012 Mike did, so I didn't bother repeating it: [Ed] posted earlier but failed to display RMWeb seems to be bust today I posted about 10:00 but like several other posts nothing seems to have gotten through to the database. No pink screen of doom just returning to the RMWeb topic. I rarely re-read my posts until the VNC is updated with a subsequent posting ... and even then ! Nevertheless apologies to Stationmaster and all for repeating but perhaps the emphasis is worthy of a further mention. Link to post Share on other sites More sharing options...
RMweb Gold The Stationmaster Posted May 31, 2012 RMweb Gold Share Posted May 31, 2012 I've not worked with smaller rail, but for code 75 I usually use a 25W Antex iron with 2mm screwdriver tip. The 18W may be a bit light for this unless you have a reasonably heavy tip that can retain sufficient heat while you make the joint. Nick I've used the 25W Antex with that bit on Code 75 rail and just right for the job but I had major difficulty with it recently when connecting wires to Code 100 (mind you the Maplin idea of flux did not help at all). Link to post Share on other sites More sharing options...
Dukedog Posted June 1, 2012 Share Posted June 1, 2012 At the risk of repeating what has already been said.... If as you say the solder just forms molten "globules" and does not flow into the joint then I suspect cleanliness is the major problem. Solder will not "tin" oxidised metal. Use some thing like a fibre glass pen to clean the area of metal you wish to tin and use 60/40 solder. The new lead free stuff is not as good as the old lead/tin solder. I use Carrs yellow flux for brass and nickel silver but just the multi core flux for electronics work. HTH Cheers! Frank Link to post Share on other sites More sharing options...
Karhedron Posted June 1, 2012 Author Share Posted June 1, 2012 Many thanks for the suggestions. I will get some multi-core solder and burnish the areas to be soldered with a fibre-glass pen. I am away on holiday next week but I will try it when I get back. Link to post Share on other sites More sharing options...
Kenton Posted June 1, 2012 Share Posted June 1, 2012 Just a further note from someone who builds kits - well known to those that do, is how useful grease can be and how much of a problem when it is not where you want it. This seems even more acute in the smaller scales or rather the smaller parts. As little as a finger smudge can stop solder flowing. You will not remove the grimy smudges by abrasion it does require a solvent. Sometimes I get the impression that Peco's manufacturing process includes the addition of some form of lubricant/protective coating to the rails to help them flex through the flexitrack sleepers. Link to post Share on other sites More sharing options...
RMweb Premium MJI Posted June 1, 2012 RMweb Premium Share Posted June 1, 2012 I have a roll of lead free solder somewhere but I can't rmember which one it is - so I can avoid it. Didn't notice until bought and it was rubbish Link to post Share on other sites More sharing options...
Karhedron Posted June 14, 2012 Author Share Posted June 14, 2012 Please can anyone recommend a good supplier for small quantities of leaded, multi-core solder? I tried Maplins but they now only carry lead-free solder so any alternative appreciated. Link to post Share on other sites More sharing options...
buffalo Posted June 14, 2012 Share Posted June 14, 2012 Just do a search for "multicore solder" on ebay. You'll find no end of suppliers for the genuine Ersin Multicore 60/40 in various diameters and various sizes of reels (and a wide range of prices). Unfortunately, it's a few years since I last bought a large reel so I can't remember who I got it from. Nick Link to post Share on other sites More sharing options...
RMweb Premium Steven B Posted June 14, 2012 RMweb Premium Share Posted June 14, 2012 I bought a role of full fat (lead based) solder from Rapid Electronics but the likes of Farnell and RS should also be able to help. The likes of C&L or Eilleens should also be able to help. Don't be worried about using lead based solder - it's not illegal to use it and it's safe enough as long as you don't eat/drink whilst soldering and wash your hands when you've finished. Unless your kids start licking the track they're not going to come to any harm from it. Happy modelling. Steven B. Link to post Share on other sites More sharing options...
Karhedron Posted June 14, 2012 Author Share Posted June 14, 2012 Unless your kids start licking the track they're not going to come to any harm from it. I wouldn't put it past them. However, thanks for the tips, I will see what I an order. Link to post Share on other sites More sharing options...
Karhedron Posted June 19, 2012 Author Share Posted June 19, 2012 Thanks for all the advice. I small dispenser of resin-cored lead/tin solder arrived over the weekend (courtesy of eBay) and it is a totally different material. It flows well and behaves the way I remember from school. Most of the gunged rail joints have now had their continuity restored (although I did introduce a short by soldering over an insulating rail joiner by mistake ). Now I just need to go back and add a few extra switches to reach the parts where the point blades no longer conduct. Thank goodness this is a fairly small layout. I consider this a lesson learned not to rely on rail joiners or point blades for conductivity in future. Belt and braces all the way. Link to post Share on other sites More sharing options...
smokebox Posted June 19, 2012 Share Posted June 19, 2012 Pleased to hear you have achieved a successful outcome. Link to post Share on other sites More sharing options...
trisonic Posted June 19, 2012 Share Posted June 19, 2012 Of course, he is probably suffering from lead poisoning now..... Best, Pete. Link to post Share on other sites More sharing options...
Baby Deltic Posted June 21, 2012 Share Posted June 21, 2012 I use one of these when soldering wire to rail or soldering code 60 to copper pins: http://www.maplin.co.uk/60w-lcd-display-solder-station-218050 It has a serious amount of grunt and will heat rails very quickly. At the moment there is a 60W soldering station available on special offer. I bought one as a reserve unit: http://www.maplin.co...otection-511927 I've not tried it out on rail yet, but I'll see how I get on using it to solder 4 rail conductors. Link to post Share on other sites More sharing options...
Karhedron Posted June 21, 2012 Author Share Posted June 21, 2012 I have a 25W soldering iron and that seems to be adequate for solder to rails. Might need to invest in a finer tip though. Link to post Share on other sites More sharing options...
buffalo Posted June 21, 2012 Share Posted June 21, 2012 I have a 25W soldering iron and that seems to be adequate for solder to rails. Might need to invest in a finer tip though. Don't go too small otherwise you'll lose the heat capacity in the tip. This is at least as important in getting the job done quickly at the wattage of the iron. Personally, I use a 3mm screwdriver shaped tip for code 75 in 4mm though, now you have the right solder, you should be able to get away with a 2mm screwdriver. Nick Link to post Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.