carb float

[skids]

That belongs in the tech tips!

[BobBaldy]

Cool tip! I bet wet sand would work even better. It would stick to the part and dissapate more heat.

[CaptonZap]

Here is another tip, from an old tinner, who has put on a LOT of solder over the years.
When you have the floats in a heat sink, wet sand, water, etc, the brass conducts a lot of heat away from the place to be soldered, which makes for a poor solder joint.
The way to overcome that is to have a BIG soldering copper. ( Soldering Iron)
It has enough heat readily available to get the joint hot, and can be withdrawn when the molten solder has gone far enough in each direction to make the seal.
As has been mentioned, make sure that the joint is CLEAN, (down to bright metal), and use flux. Rosin or paste will work. Cut acid, hydrochloric acid that has had zinc dissolved in it till it quits foaming, will work on copper.
The iron should be cleaned to bright copper, and applied to Sal ammoniac while hot. When it starts smoking, apply some solder, and the solder will coat the iron. This is called tinning the iron. You cannot do a good job of soldering with an un tinned iron.
After an oxidized coating covers the tinned part, from not being used for a few minutes, dip it in flux or acid to clean it, then apply to the solder joint, along with fresh solder.
Do this in a well ventilated area.
I have improvised a soldering copper from various things over the years, but for the floats, I would advise a solid piece of copper 1/2 inch in diameter, 2 or 3 in long, formed to a blunt point, and heated with a propane torch. Where to find the copper is a problem, since the price of copper has prompted the scrappers to take anything that is not nailed, or should I say soldered, down.
Lightning arresters might be one source, or borrow one from a stained glass shop. They run into the same problem of quick heat, when they solder the lead strips for the glass. And the irons are about the right size for the job at hand. Plating shops may have some old bus bars that could be utilized.
I would advise against using a torch to try to solder a float. An accomplished jeweler might be able to do it, but if you are one, you don't need to read this.
Good luck. CZ