Whilst making some of the parts for the miniature traction engine I wanted a much finer silver soldered joint and so I bought some Cooksongold Silver Solder Paste to try.
I bought 10g of the easy paste direct from Cooksongold. As you can see this comes in a syringe with a fine tube attachment. When it arrives it has a warning label attached:
The warning label is quite drastic as the product contains Fluorides and Borates. It is very harmful if swallowed, you need to wear skin and face protection. Also, must not be released into the environment.
Honestly, you need to take a lot of care with this product. Follow the instructions and treat it with respect.
The silver solder is available in three different temperature ranges. I used the easy or lower temperature range product.
- Easy: melting range of 705°C – 723°C
- Medium: melting range of 720°C – 765°C
- melting range of 745°C – 778°C
All types have an active fluxing range of 550 – 850°C.
Also, it is available in 10g and 30g syringes. 10g feels like a very small amount, but having used it it does go a long way. It states on the website “Please note, this is supplied without a lid”, not sure really what to do other than wrap the end in plastic and secure it with tape to try and stop it possibly drying out.
This is primarily aimed at the jewelers, but must admit that this is a great addition to the model makers arsenal.
I easily managed to silver solder the elements of the small hinge on this door. Cooksongold silver solder paste is Much easier to use than separate flux and silver solder rods.
Cookson gold have a great blog post on using this paste: What is Solder Paste?
Examples of Use
Silver soldering a sandwich of 3 layers of brass to make a bearing block for the Burrell.
The silver solder paste comes into it’s own on small parts like this.
I silver soldered the fittings to this siphon tube using the silver solder paste.
The copper pipe is just 1/16 inch OD and so soldering this was like soldering jewellery. I concentrated the torch on the larger parts first. Being careful not to overheat the copper tube or the olive fitting.