If you do high speed, or high torque machining you should seriously consider the benefits of shrink fit technology.
Heat shrink tooling is considered one of the best methods for high-performance machining. The mold and die industry was the first segment of the manufacturing market to look for more precise tool holder options, due to the need for a slim nose and long reach. Today, every segment of manufacturing can benefit from the advantages of shrink fit tooling.
In this article, I’m going to show you the basic introduction to shrink fit chuck.
Tool holder Selection
When looking for tool holder solutions for any type of machining, it is always good to focus on the three main features that a tool holder must bring you:
Rigidity comes from sufficient taper contact and proper clamping of the tool holder in the machine tool spindle.
Accuracy comes from minimal run-out at the cutting edge of the cutting tool when clamped in the holder.
Balance comes from a balanced assembly of the tool holder (including all accessories such as pull-studs) and cutting tool combination.
You may also often think about the following:
Geometry of Tool Holder
Geometry is important to avoid collisions with the workpiece. In regards to the EDM process, electrodes must be machined accurately and efficiently. Oftentimes, deep ribs are required in the part process and may present challenges. Also, deep cavities such as large door panel or bumper molds require deep reach with extreme clearances.
Cleanliness of The Tool Holder
Cleanliness is required to avoid excessive run-out, especially when machining graphite.
Extending Cutting Tool Life
Since high-end cutting tools are needed to obtain the best performance in the shortest time possible, a tool holder that extends cutting tool life can be advantageous. These cutting tools often have exotic coatings that lend to an expensive price.
Surface Finish at Higher Speeds and Feeds
Some tool holders are used with lower depth-of-cuts, which translates into better surface finishes. This makes balance even more important to minimize vibration at the cutting edge of the cutting tool. Also, proper chip evacuation provides better finishes.
Advantages of Shrink Fit Chuck
There are 10 inherent benefits that a good shrink fit chuck can offer:
A properly produced shrink fit chuck should be able to guarantee 0.00012’’ (3 microns) maximum run-out at three times the cutting tool diameter.
Availability of Slim Profiles
Shrink fit chucks are available with three-degree draft angles and very slim profiles. They can also be modified to be straight walled, if needed, in order to prevent tool holder collision with the workpiece.
A shrink fit chuck grips the cutting tool 360 degrees around the shank. This leads to a very high gripping torque that prevents the cutting tool from moving during roughing or finishing operations.
Extended Reach Options
Shrink fit chucks can use shrink fit extensions that provide the user with many options with standard products. When machining deep cavities, one can place shrink fit extensions into standard shrink fit chucks, getting unsurpassed tool holder lengths with very little run-out.
Balance Repeatability and Balanceable Options
Shrink fit chucks can offer some of the best balance repeatability of any tool holding system on the market, since there are no moving parts. In many cases, if a shop purchases a properly balanced shrink fit chuck with correct accessories (such as pull-studs) and uses good cutting tools without inherent unbalance (such as flats or unequal spacing), then they can often have good balance characteristics for running at high speeds without doing an additional fine-tune balancing.
Reduction of Tool Changing Time and Less Tool Holder Accessory Inventory
Nothing beats the tool change time of shrink fit chucks if the process is joined with a capable inductive shrink fit machine. Tool changes can be done in 5 to 10 seconds, and most importantly, consistently. This allows the tool holder assembly to be in the machine making chips more of the time, rather than out of the machine waiting to be changed. Also, a shop needs very little additional tool holder accessory inventory (i.e., collets, nuts, seal disks, etc.). This simplifies the process.
Cleanliness of Setup
A shrink fit chuck typically is a sealed system by design. Therefore, the introduction of contaminants in the bore is minimized. If contaminants are introduced to the bore of a tool holder, oftentimes run-out accuracy is compromised.
Shrink fit chucks have convenient methods to deliver coolant down to the cutting edge of the cutting tool. This helps with the proper removal of chips and can also aid in providing better finishes.
Consistency of Setup
Shrink fit holders provide the great repeatability from tool holder setup to tool holder setup. This is especially beneficial for those shops running lights out. For example, all tool holder setup operators set the tool holders the same with shrink fit holders. There are no variables—such as over-tightening or under-tightening a collet nut or not cleaning out a chuck sufficiently.
Availability of Shrink Chucks
Most of the major tool holder builders in the world now offer shrink fit chucks as a standard.
If you have any question about shrink fit tooling, I recommend that you can visit SYIC’s website and feel free to send inquiry to them. SYIC is the company of specializing in shrink fits, tool holders, and milling chucks etc. Learn more details about their products, try to check out their product pages!