# SPEAKING OF RESISTANCE SOLDERING?



## John J (Dec 29, 2007)

Does anyone have some pictures of the joints you have using this method? 

I have a bunch of 1 FT and 2 FT sections of track. 

Would this be a good way to join them together to make longer sections?

AS you know I do not run track power.

Lastly any one got a link to resistance soldering units. 

JJ


----------



## armorsmith (Jun 1, 2008)

John, 

If you are looking to purchase one, just do a search online. There are a number of good quality units available. 

Bob C.


----------



## John J (Dec 29, 2007)

I was hoping some one would post pictures of the joints That hey have reisitance soldered.

I down loaded a PDF from another thread on how to build one.

I have a bunch of short pieces I would like to join together. That could be expensive to use jointers I think. 

JJ


----------



## John J (Dec 29, 2007)

WHAT









Youse Guys taint got no pictures of some resistance soldered Rail Joints?

I am apauled.









JJ


----------



## Greg Elmassian (Jan 3, 2008)

If you are trying to join sections together, you cannot solder them without some type of joiner. The solder alone will not make a mechanical joint. 

All you need is a mechanical connection, so soldering in your case is superfluous. 

Welding or brazing would make a mechanical joint, but too much heat for the ties. 

I'd bolt up joiners, or make "angle bars" and drill through the web and bolt sections together. 

Regards, Greg


----------



## John J (Dec 29, 2007)

I thought there was a whold bunch of you guys doing this. I guess not 

JJ


----------



## izzy0855 (Sep 30, 2008)

John, 

You can spot weld .375 nickel tabs to each joint then solder the tabs together after you join the two sections together? 

Rick Isard 
Cordless Renovations, LLC


----------



## Greg Elmassian (Jan 3, 2008)

The club in San Diego has a resistance soldering unit. It is mostly used to solder jumper wires on brass track. 

Soldering is not a good mechanical connection in most cases. 

Welding is significantly different from soldering. 

Regards, Greg


----------



## armorsmith (Jun 1, 2008)

John, 

Using a resistance soldering outfit can make a good quality mechanical joint, provided you have two factors in play. First you must use a good grade of silver solder. Plain soft solder will not accomplish the desired result. The second and just as critical is surface area. The larger the surface area with a tight fit, the stronger the mechanical joint will be. Consider that in non shock service, a properly prepared 1/2" copper water pipe joint made with (old terminology here) 95/5 solder will withstand 100 psi. Consider the large surface area that the solder has to work with. Your rail has a far smaller surface area, therefore the recommendation to use silver solder. 

For what you are trying to accomplish, a simple butt joint of two ends of rail will not be sufficient. If you were to scarf the ends of the rail (file them back at a shallow angle - similar to the angle for a switch frog) you would greatly increase the surface area, making for a more secure mechanical joint. A LOT of filing. Also, in order for the rail to be straight, the angles would have mate perfectly or you would impart a vertical kink in the rail. 

I believe what you want to do is attainable, but is the effort cost effective? 

Hope I have tossed a bit of light into the subject. 

Bob C.


----------



## Greg Elmassian (Jan 3, 2008)

Add into the continuous pressure from expansion and contraction and fracturing is a danger. 

I would think you would want a long lap joint. 

Just don't think it's the right technique. Get some thing brass strips, cut the width of the web and spot weld. 

Regards, Greg


----------



## John J (Dec 29, 2007)

Ok I see what you are talking about.

I thought it was more popular than it is.

It appears to be labor intensive.

I will just get a bunch of Aristo slip joints which are not that expensive and solder the pieces together.

JJ


----------



## Greg Elmassian (Jan 3, 2008)

Yep, would be a ton of work. 

Clamping with the Aristo joiners and then soldering will hold ok, but I have seen the solder fracture in one of those joints too. (This is because the standard Aristo joiner is not a close fit like a copper pipe fitting) 

Resistance solderers are most popular just soldering electrical jumpers. 

Keep your eyes out for a spot welder, but again, you would need "angle bars" like the prototype that fit the web of the rail closely. Maybe the right width metal strip could be found in bulk. I don't think you need to give up on your basic idea, you just need to use a different method. 

Regards, Greg


----------



## armorsmith (Jun 1, 2008)

Resistance soldering and spot welding work in the same principal, creating a short circuit to generate a lot of heat in small area very fast. The primary difference is the power applied and the material being joined. Resistance soldering/brazing uses a filler material in the joint, usually of a brass or silver alloy (with appropriate flux), depending on the base metal. Spot welding on the other hand is usually utilized on steel sheet metal by way of fast high heat combined with a pressure element to 'heat weld' the two surfaces together. I have personally never seen brass spot welded. I have done a lot of brass brazing steel sheet metal over the years. And I have silver soldered and soft soldered a ton of brass, but never spot welded brass. I believe the difficulty in spot welding brass is, like aluminum, brass has a very narrow plastic state between solid and liquid. That makes temperature control very critical if you want it to stick and not be a puddle of brass under the contacts. 

Bob C.


----------



## Greg Elmassian (Jan 3, 2008)

Interesting patent from 1930 by pullman car co on spot welding brass and aluminum...

So someone figured it out 81 years ago..

*http://www.freepatentsonline.com/1770540.html* 


Greg


----------



## derPeter (Dec 26, 2010)

Good evening,
i use this made in England since a couple of years, works very well for brass soldering
greetings from derPeter


----------



## derPeter (Dec 26, 2010)




----------



## lotsasteam (Jan 3, 2008)

Check back with your local Dental laboratory,most resistance solder units are obsolete,they are using laser welders($ 50 000.00 ) 

Manfred


----------

