Ask any polisher what the hardest part of his/her job is and most will tell you the same thing – stoning. It doesn’t have to be that way. Here is a simple technique that not only makes stoning easier and more enjoyable, but actually cuts 30 percent off the time it takes to do a [...]
Ask most shop owners what the number one reason is for new molds failing their first sample and you will most likely hear “material sticking in the ribs.It is not uncommon for a tool to have its ribs and slots repolished two, three or more times before the tool works cleanly. […]
Checking for Positive DraftOn occasion tool marks can be so deep that they reduce the draft or the polisher accidentally takes off the draft. The key is to always check for positive draft by putting a six-inch scale on the wall and comparing the angle it makes to the parting line. It takes just a [...]
To provide the high-performance results demanded in today’s moldmaking, many indexable-insert ballnose endmills use PVD-coated, precision-ground, micrograin- carbide inserts. Experience shows that such inserts perform best with sharp edges, which represents a departure from the conventional wisdom that extra-strong edges are required to stand up to hardened materials at very high feedrates. […]
In addition to modular endmilling systems specifically designed for mold-making and other copymilling applications, general indexable-insert endmilling systems are available that include components for high-speed/high-feed finishing of molds and dies. […]
Both solid-carbide and small indexable-insert ballnose endmills are capable of the speeds and feeds required for high-speed finishing of molds. Moldmakers should keep in mind, however, that the indexable-insert tools offer important cost advantages – starting with a much lower replacement cost and no regrinding. […]
When looking to purchase a machine tool for your shop, it is vital to choose a machine tool supplier that designs, engineers and builds its own components. That way you are ensured of optimum performance at greater accuracies. And—if something should go wrong—your supplier can quickly get to the root of the problem since they [...]
Cutting speed and surface finish are frequently the topic of discussion on shop floors of hundreds of mold shops. There’s a relentless quest for reducing machining time per mold, achieved by faster feedrates and traverse rates. Of equal concern is assur-ance that optimum surface finishes are being produced by the machining process with little or [...]
The two major enemies of the spindle are: (1) heat and (2) contaminants (namely, chips and coolant invading the bearing system). Find out what design features are included (or available as options) that protect the spindle. Historically, the most common cause of spindle failure has been bearing failure due to contamination from coolant ingress, condensation, [...]
Dealing with the sheer size and weight of a large mold can be a big challenge. This often leads to excessive labor, the need for special equipment, multiple setups and potential inaccuracies. […]