Aluminum Framing Standards 3

[rc3ng]

I was wondering if there are any standards for the size and depth of T-Slot Aluminum extrusions. I have previously used Bosch Rexroth structural framing extrusions (LINK) and they work really good.
Now I am in the process of designing a custom extrusion that requires some T-Slot fasteners similar to those produced by Rexroth (LINK).

Are there any standard T-Slot dimension that I can use? I just want to make sure we can easily purchase the mounting hardware from any general fastener supplier.

Thanks!

 

[MintJulep]

The easiest way would seem to be make your slot sizes to accommodate a standard hex-head bolt and avoid "special" T-slot bolts all together.

 

[rc3ng]

Thanks! It's actually a great idea. I only worry about the smaller surface of the bolt head compare to those special bolts and nuts. Is there something that I am missing?

 

[MintJulep]

I suspect you'll find that the limiting factor on strength is the extrusion, not the bolt. So design the extrusion wall thickness to get the strength that you need.

 

[rc3ng]

For M6 hex screw, the head diameter is 9.78mm. If the bolt diameter is subtracted from it, only 1.89mm remains. That is maximum over lap of the screw head with the edge of the extrusion:

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Is this OK? Or you meant to have a washer as well?

 

[rc3ng]

Oh, the web browser messed up my artistic schematic!

 

[imcjoek]

T-slot nuts are pretty common for things like milling machine tables. Why not design off these? They are easily available in a variety of sizes from suppliers like Mcmaster-Carr.

The nuts of extruded aluminum framing are a bit different between manufacturers. (I've tried Maytec and 80/20, and they are not exactly identical)

 

[rc3ng]

I checked their dimensions too. Like you said, they are not exactly the same. I think I should either go with the cap screw idea or use the expensive t-slot nuts...

Thanks for your help!

 

[Jboggs]

I have used various manufacturers' extruded aluminum structural systems for years. There are many common sizes, both metric and imperial, but no commonly recognized standards of the industry that I am aware of. To be safe I would just make sure I get my framework and my fasteners from the same manufacturer. that way you know they are designed to work together.

 

[rc3ng]

It's good to know there is no standard for that.....I'm surprised! I should send ANSI a letter

Thanks everyone for clarifying this issue.