The smokebox door hinge for the Burrell has caused me a lot of grief. I thought I would share below the disasters that I’ve had on the way to creating a hinge that I’m happy with.
So, I went back to basics, read a number of articles about silver soldering. Because, even though I’ve done quite a bit of silver soldering it just felt like I was getting something wrong.
One article mentioned approaching the problem in stages, this made me rethink the door and etched plaque. What if I fix the etched brass to the door using rivets? This would look better and allow me to strap the hinge to the door.
I machined two slots 3mm wide and 0.3mm deep into the mild steel door. The door edge was aligned on the milling table using a simple engineers square.
I used a 2.5mm diameter end mill to machine slots in the heads of 8BA bolts. These would form the smokebox side of the hinge.
Note that I drilled a threaded a piece of 1/4 inch diameter brass so that I could more easily hold and machine the bolts. These little simple mandrels are worth keeping as they often come in handy when working with small threads.
The 8BA cheesehead bolts easily accept the 2.5mm diameter half depth round slot. The basic premis was that this would give me more area to silver solder the hinge to. Hence more strength on the smokebox side of the hinge.
For the silver solder I decided to try using a paste. This 10g syringe of CooksonGold easy silver solder was not cheap (~£16 in 2021). However, it is very easy to control and you don’t need much to form the joint.
This easy silver solder paste contains the silver solder and the flux. Note though that you still need to thoroughly clean all of the joints. I cleaned all of the parts in methylated spirits before drying them and pickling them all for 20 minutes.
I thoroughly dried them all before carefully assembling.
A simple stainless steel jig created from flat sheet material. All four edges of the jig are folded at 90° to add some stiffness and try to stop warping during heating.
The silver solder paste is easy to apply from the syringe and I put a small amount between all joints.
You will see that the hinge is spaced out to ensure that the smokebox side parts using the bolts do not join onto the door.
The final door hinge for the Burrell. Still some cleaning up to do, but this is much neater. The straps add to the strength and are closer to the original design.
Now I just have to etch another brass plaque and rivet it to the door.