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Which 80/20 Aluminum Extrusion Fastening Method is Best for You?

Posted by Mark Howe on September 12, 2012 09:04 AM

Open up the catalog (section 3 to be exact) and you will see over 20 different pages of t-nuts, screws and fasteners. Then hop over one more section and you will see a few dozen joining plates and brackets. Little overwhelming if it your first time parousing the catalog.

We are going to break down the 4 most common aluminum extrusion fastening methods and go over an advantage and disadvantage for each one.

1) Anchor Fasteners (Pg 242-244)

This is one of the strongest fastening methods 80/20 Aluminum Extrusion offers. It combines a 5/16-18 SHCS (socket head cap screw), Zinc Casted Anchor Cam and a standard t-nut. A counterbore is required to insert the anchor portion of the fastener into the T-slotted profile. 80/20 can machine your counterbores in any of our 54 T-slotted profiles to match your exact specifications.

Advantages:

  • Allows infinite positioning along the T-slotted Profile
  • Provides a vibration-proof, clean, flush-connection.

Disadvantage:

  • A Counterbore machining process is required to place anchor fastener in extrusion.

2) End Fasteners (pg 245-246)

The end fastener is a clean, hidden method for creating 90deg connections. The end fastener is a 5/16-18 BHSCS (button head socket cap screw) combined with a special winged tab that slides into the t-slot. An access hole needs to drill into the mating profile so you can access the screw head with the tool to tighten the screw.

Advantages:

  • Hidden Connection and easy to position
  • Winged tab help prevent the mating profile from rotating

Disadvantage:

  • Lack of adjustability. You will need to drill new access holes to move the connected location.
  • Machining required: Access hole and end tap on extrusion.

3) Joining Plates (Pg 290-303)

80/20 provides a ridiculous amount of standard joining plate options and they also have the capability to create custom plates as well. The range goes from a simple 2 hole plate to a massive 20 hole cross joining plate. Each plate is fastened to the t-slot using either BHSCS or FBHSCS (flange button head socket cap screw) and economy t-nuts.

Advantages:

  • Number of options. The have a joining plate that will fit any application.
  • Adjustability
  • No machining required

Disadvantage:

  • Increase assembly time
  • Potential increase of material costs (for larger plates only)

4) Corner Brackets (Pg 269-289)

There are a number of corner bracket options but not as many options as the joining plates. The corner brackets come in two main categories, the 90deg angle stock and the 90 deg gusset. The standard corner bracket starts with a 2 hole set up and expands to the 18 hole bracket.

Advantages:

  • Number of options. The have a joining plate that will fit any application.
  • Adjustability
  • No machining required

Disadvantage:

  • Increase assembly time
  • Potential increase of material costs (for larger plates only)

Fastening methods vary from application to application. You need to fully understand the requirements of your application before choosing. Will you need to adjust the extrusions? Will you be able to access the fastener with a tool? How strong of a conection is required? These are just a few of the potential questions that surface when your working with 80/20. Take a few extra moments when designing your application to think about the fastening methods. Look at all the options in the catalog and review the benefits and shortfalls of each fastening method before you complete your design.

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Topics: aluminum extrusion, t-slotted extrusion