From the book Building Superior Brazed Tools  Buy the Book

Carbide Wetting Analysis Test #1 

We were supplied CWF7150 saw tips.  They came two ways; one was untreated and one had a nickel coating. 

The standard is an even flow to all four corners as shown below.

First wetting test 

Left pictures shows a very small piece of silver solder.  The middle shows the parts in the induction coil.  Right are the finished parts.  (These are also the left two parts in the top picture.)   Flow wasn’t bad but not great.   

Full piece of alloy wetting test

The four on the left were tested with a very small piece of braze alloy.  The four on the right were tested with the right amount of braze alloy for this size tip.   The plated tips were marginally better but none of them worked well enough to be saleable in today’s market unless they were really cheap.   The wetting is about where the U.S. was 15 to 20 years ago.  They will stay on the saw pretty well but I don’t think they will look good. 

This is actually a bit more alloy than we would use for production (left pic.)  The parts were pretty heavily fluxed and were heated to a red heat which was a bit too hot but we wanted to give  them every chance.   

Wetting Analysis Test #2 

Two carbide saw tips with a piece of .115” long wire, which is much too small, and two carbide saw tips with A piece of .210” long wire which is about right depending on customer preference.

Two carbide saw tips with .115” wire on the left.   Flow is very good.  Arrow points to slight flow discontinuity.   This isn’t a problem but it isn’t quite ideal.   Tips wet beautifully and are very saleable.   

Strength test 

We pretinned some tips, let them cool and then brazed them onto six inch long bars.  This gives a nice long area to grip and to get good leverage.  We tried to twist them.  They wouldn’t twist off or break using normal force.  We sent the parts to the customer for their testing.