CNC TABLES: T- Slot

cnc fixture, cnc clamping

T-Slot CNC router tables are probably what you'll find on most small hobby CNC routers. Quite often they have a dedicated extruded aluminum T-slot panel that makes up the entire table.

 

Larger CNC routers have tables that consist of aluminum T-slot bars going across the X axis alternated between strips of MDF. On the more sophisticated machines the MDF panels can be fixtures for vacuum clamping.

 

Clamps that fit into the T-bar can be as simple as hex-head bolts and knobs to basic crooked arm hold down clamps or custom made wood or aluminum fixtures.

 

Advantages of CNC clamping with T-Slot Tables

• They're cheap
• Simple technology to use.
• No noise. You don't have a vacuum pump working in the background
• Does NOT consume huge amounts of electricity like the blowers used on flow-through CNC vacuum tables.

Disadvantages of T-Track CNC router tables.

The biggest challenge in using T-track systems is trying to modify traditional clamping methods to be low profile so you're not slamming your cutter into the clamps all the time and destroying your spindle head at worst or snapping your router bits at best.

With small machines the software that comes with them, rarely have the capacity to create paths that navigate around your clamping systems, so you have to do this manual. Murphy's Law, suggests that when you least expect it, you'll forget to re-code the return path to avoid one clamp.

Aside from that if you intend to cut a lot of full-sized sheet material you'll find out pretty quickly that using T-track cnc fixturing doesn't help in keeping the middle of the sheet down. The sheets tends to bubble in the center of the panel. If depth of cut is important this bubble will give you less than perfect results.

The trick in T-slot clamping is in the design of the clamps. How can you get the downward pressure you need, the flexibility to handle all different shapes and thicknesses and the ability to move all that away from the travel of the head.