Mounting the T41U5XBB

This blog discusses mounting options for the T41U5XBB. In general, the best enclosure is a metal box which forms a faraday cage.

When planning your grblHAL based system several issues need consideration.

Mounting location of the board.
Room for connecting wires and ferrules, if used
Space for wire bundles.
Ease of wiring - inserting wires into screw terminals in a cramped area can be difficult.
Location of external connectors (for orientation to minimize wire runs and crossings).

In general, I recommend having at least 40mm/1.5" of space around all 4 sides of the board to make wiring easier. It is possible to do with less but the tighter it is, the harder wiring will be.

Simple mounting

The simplest mounting scheme is to drill 4 holes (see template) and use 4-40 or M3 screws with nylon standoffs (or other insulating tubes). This works well though can make it hard to access in deeper enclosures. If the enclosure material accepts it and there is space on the other side, #4 sheet metal screws work well. Adjust drill size as appropriate. Also, be aware that the sheet metal screws are sharp and can cut if exposed. Here is a drilling template that includes a 1.5" perimeter.

Mounting brackets

A mounting bracket that raises the board has some advantages - it makes it easier to work on in a deeper enclosure and it can allow wire bundles to run under the board to avoid clutter. Here is a design for one that I used in a MillRight Mega V upgrade. I made them out of 22 ga sheet metal - cut out using sheet metal shears and bent with a home made brake. Note that I powder coated them but that is not necessary.

.

I plan on adding a front panel to give access to cycle start, feed hold and EStop so wanted the board to be more accessible. The bracket holds the board about 2 inches above the bottom of the case. I cut and bent from 22 gauge steel. I used 4-40 screws/nuts on the bottom and #4 sheet metal screws to hold the board in place. If you decide to use 4-40 or M3 screws for mounting the PCB, use a 1/8" drill bit.

Use the above template for drilling the bracket mounting holes. You can use #4 sheet metal screws, 4-40 or M3 machine screws. Adjust your drill size accordingly.

Use this template for brackets that mount on the long edge of the PCB.

Use this template for brackets that mount on the short edge of the PCB.

About Me.

I'm Phil Barrett, a long time CNC enthusiast. I run a small company, Brookwood Design, that makes several breakout boards for grblHAL and love to help people get the most out of their CNC machines.