That would be an advantage
the idea I had was to have the chamber so the gas goes in, but doesnt go out untill the casting has finnished, so that there is a high pressure on the molten silver, which i can only assume would result in a better cast?
How much would nitrogen cost and where would it be sold/what is it used for?
Edit - Top of gpu bblock has just got back from being silver soldered. Pic is attached. It hasnt been cleaned up or anyhting yet so where the copper got hot and oxidised can still be seen. When finnished it will have a bright mirror shine from lapping and pollish, although It wouldnt affect perofrmance to leave it as is...
On the inside you can see there is a divider. this is to force the water to go into the channels that I have yet to make into the silver. If it is too restrictive I will make it smaller.
An alternate way I could have made the lid would have been to use 22mm copper pipe, cut along the pipe in half. Then the inlet and outlet could have been at the ends and would have reduced any dead areas from it. I did consider this but decided this way would look nicer and the ends wouldnt be in the way of the screws which will hold it down.
The channels I will make in the silver will Be about 3mm in from the edges of the copper going all the way along. they will be made with either a steel cutting disk which has teeth, as shown in the pic, or the other disk which is reinforced and a lot wider (steel = 0.25mm, reinforced = 1.3mm). the steel one would be better as i could make more channels, but it depends on how well it can cut silver, as it is designed for cutting wood, I assume.