Solder welding a link to a battery post will work if the post has any height above the surface of the battery. If the post is melted down to the top surface of the battery, than you will have to heat sink the plastic and lead seal.
You can get this heat sink material from a welding supply shop. It looks like white high temperature putty. Applied this compound on the lead seal which is a ring imbedded into the battery top seal and about 1 inch around built up to about 1/2 inch high. Remove the battery caps to vent any hydrogen which is best to do a day before. Roll up a short length of paper towels, wet it with distill water and use it to plug the fill necks. Do not let this plug touch the electrolyte. Cover the entire to of the battery with several layers of wet paper towels with the post you are working expose. Fill a spray bottle with distill water which you may need to applied more water surrounding the post area as you work. I do this preparation work, if I am lead welding on a lead buss bar link which is use on industrial batteries or melting on a new post using a post mold. It is best to use solid lead wire, instead of solder with a flux core. You can get this solid lead wire from a sporting good store that sell fishing supplies. Come in rolls of 1/8, 3/16 and 1/4 inch diameter. I use the 3/16 inch size. Do not use the standard type plumbers solder flux. I use a all metal flux than you can get from a welding supply store. I use a this flux for silver soldering. You can actually weld a piece of stainless steel to a glass surface with this stuff. The touch tip for this type of work, is call a leading tip which put outs a long narrow flame tip that also have a long oxygen flame that is as long as the butane flame. Inserting A standard touch does not work good with a post mold because the flame will blow out, but will work with surface welding. Instead of doing all of the above, I would still use a bolt down adapter as the following: If using the screw on post adapter, make sure the bolt is stainless steel. If not stainless steel, get the adapter that does not have the threaded stud in it, but is still has internal threads. Drill through the internal threads out to the top of the post and install a longer stainless steel bolt which you can torque down into the existing post with a tap thread hole. Roland ----- Original Message ----- From: "Lee Hart" <[email protected]> To: "Electric Vehicle Discussion List" <[email protected]> Sent: Friday, March 29, 2013 12:57 PM Subject: Re: [EVDL] Re-casting battery post that melted away? > On 3/29/2013 11:20 AM, Marcus Reddish wrote: > > Why recast it? Drill it and put in a bolt. Especially if used only for > > 12v. You can get self-tapping bolts at hardware store. > > On Mar 28, 2013 2:18 PM, "Cor van de Water"<[email protected]> wrote: > > Because it's on a flooded lead-acid battery. If you mix metals, you have > severe corrosion problems! > > I don't have the molds (or talent) to make a new post. When I've had > them melt off, I took them to an "old timer" at a big industrial battery > store. He made a new post in just a matter of minutes. He made it look > easy! > > So I tried it; I just turned postless batteries into useless batteries. > :-( > > I also tried buying an "adapter" to convert a side terminal battery into > one with normal automotive posts. This is basically a steel bolt > embedded in a lead automotive battery post. They expect you to screw it > into the threaded hole in the side of a side-terminal battery. I > threaded a hole in a partially melted post, and screwed in the adapter > (plus plenty of grease that was supposed to keep the acid out). It only > worked a short time, and then rapidly corroded into junk. > > I think the ideal solution is to weld your wires directly to the > battery; no post or terminal at all. I *have* successfully dunked the > wire or battery bus bar in a solder pot, then welded it to a battery > post (just heat until they flow together). My connections looked ugly, > but never failed again. > > -- > Ingenuity gets you through times of no money better than money > will get you through times of no ingenuity. -- Terry Pratchett > -- > Lee A. Hart, http://www.sunrise-ev.com/LeesEVs.htm > _______________________________________________ > UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub > http://lists.evdl.org/listinfo.cgi/ev-evdl.org > For EV drag racing discussion, please use NEDRA > (http://groups.yahoo.com/group/NEDRA) > > _______________________________________________ UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub http://lists.evdl.org/listinfo.cgi/ev-evdl.org For EV drag racing discussion, please use NEDRA (http://groups.yahoo.com/group/NEDRA)
