VersaFrame Tube Cutting Fixture

Technical Technical Discussion
1

https://drive.google.com/file/d/0B67Uv_S_WWjpMG01a2VXaWhjR3c/view?usp=sharing

For the last few years Team 2451, Pwnage, has been using 1"x1"x.04" VersaFrame Tubing to build our chassis. Last year one of our alumni (current mentor) converted an existing fixture to speed the cutting process and increase the precision of cutting the VersaFrame tubing to size. During the offseason he has designed and manufactured a brand new cutting fixture. This fixture is installed in a Curt Vise in a Bridgeport mill. A horizontal head attachment is used to drive the slitting saw blade in a vertical orientation. The finer the toothed blade the less likely the thin wall tubing will be bent during cutting. The angle of the cut is adjustable and graduated marks are provided for quick adjustment. The tube is positioned in the correct location using a precision pin inserted through the existing VersaFrame mounting holes which engages a precision reamed hole in the fixture. This allows for a single value to be changed in the Prototrak 2D CNC controller, the angle to be adjusted (if needed) and the blade to cut the tube to the correct length.

https://drive.google.com/file/d/0B67Uv_S_WWjpeERzTFlQbFVDQVE/view?usp=sharing
https://drive.google.com/file/d/0B67Uv_S_WWjpRl9ld2RUSWdEZG8/view?usp=sharing
https://drive.google.com/file/d/0B67Uv_S_WWjpWFVmT1ZSWHlYVUk/view?usp=sharing
https://drive.google.com/file/d/0B67Uv_S_WWjpUjZ2ZmtBSDR3dkU/view?usp=sharing

2

Why do you need to cut so precisely (and tie up a nice machine) if you’re attaching with gussets/sheet anyway?

3

The main reason for the fixture is to save time.

Though, when you cut and join the tubes precisely, allow them to butt up against one another, the load in not 100% on the rivet and gusset. The load can be distributed directly from one tube to the other. This makes the fastening stronger and the complete assembly more rigid. Especially if you are using .04" wall tubing which has a lot of deflection under load when only using rivets.

We have six Bridgeport/Prototrak mills.
There are times where we “tie up” all six but there is usually at least one open. The actual cutting takes the same amount of time as any other method. The setup time is minimal when you look at the overall time savings. We used to hand measure, mark lines with a square or a protractor and then manually cut the tubing. When you have 50 pieces to cut the fixture is a big time saver. Plus the tubes fit together the first time.

4

This is a great idea that should save you a lot of assembly time. Can this jig be used for cutting other materials such as shafts? I will see if we can come up with something similar for the basic equipment we have (bandsaw, hacksaws).

I now have a strong case of shop-envy.

5

Seriously. Six mills? I don’t think we even have six shop tools in total!

Oh well, we’ll get there… :smiley: