Counts

1.  All counts will be – zero to +2 parts per 250.

Size

1.  -0 / + .007” is industry standard.

2.  -0 / +.003” is current practice.

Chips and cracks

1.  Chips no more than one half the grinding tolerance. 

2.  Chips no more than 0.003” in any dimension.

3.   No internal or external cracks. 

Edge radius, chips and parallelism

When the part is held next to a straight edge the maximum gap will be no more than 0.007” to account for the total of edge radius, chips and parallelism.  

We used 30x  magnification for inspection with standard light.  The gap on the right side of this tip is about 0.003”.  On the left side the gap goes up to about 0.007” with the largest chip about 0.003”

Wettability

1.       A small piece of silver solder (app. 1/5 the length of the surface will flow completely and evenly out to all four corners. 

2.       A piece of silver solder 2/3 as long as the tip surface will flow out evenly to all four corners and will create a smooth, consistent hump. 

Pretinning

Even flow to all four corners.

Average pretin silver depth is 0.007” to 0.010”.

Bond Strength

The tip will braze to the steel plate so that the carbide will break or the steel will rip but the tip will not come off.   These two pictures show tips where the surface treatment peeled off.

Grades

Each grade will be specified and defined by grain size, chemistry, transverse rupture strength and hardness, preferably Rockwell hardness.

Chemistry

Each batch will have available a chemical analysis if requested. 

Delivery - As promised.