Building a Steady Rest in 5 Days

Need some steady rest design and manufacturing advice.

So, basically what the title says. I am in a college rocket team, and we commonly work with 4-7in diameter metal tube stock that is often up to 2 feet in length. Operations like facing or drilling radial holes are not the best, but especially bad is turning and boring.

Solutions we’ve tried are making one-off shoulders every time to fit into the tube and adapt to the live center, and other various tricks to minimal levels of success. We also don’t have a bull nose live center. When it comes to boring, we just pray.

Our final solution after much suffering was to give in and build a steady rest, but after much time spent in other areas, we only have 5 days left. As such the main goal of this steady rest is: time (or lack thereof).

We want to be able to quickly make a good enough steady rest that we can manufacture from scratch in 5 days to face, turn, and bore a 5 inch tube that is 18 inches long. It doesn’t need to do more than that and will likely not need to endure more than half a year.

So with all that said, here is the basic idea: two 1/4” steel plates that are waterjetted with blocks (metal, NOT 3D printed) sandwiched in the middle of them. The blocks will have through holes to allow for bolts (or pins?) to join the plates and blocks together. The blocks will also have a threaded hole going in the radial direction to allow a bolt to pass through and serve as the steady rest fingers. The rest is self explanatory from the picture.

So, do you think this is doable given our time constraints? We have all the stock necessary it is mainly a concern about manufacturability and if it will actually work. How should we lock the bolt fingers in place? Assuming we put something on the end of the bolts like a bearing, does the bolt idea itself actually work? Will this design be strong or rigid enough?

Any and all help is immensely appreciated. We are relatively amateur machinists so please keep that in mind. We have access to 3 axis CNC mills, as well as a manual mill and lathe.

Need some steady rest design and manufacturing advice.

So, basically what the title says. I am in a college rocket team, and we commonly work with 4-7in diameter metal tube stock that is often up to 2 feet in length. Operations like facing or drilling radial holes are not the best, but especially bad is turning and boring.

Solutions we’ve tried are making one-off shoulders every time to fit into the tube and adapt to the live center, and other various tricks to minimal levels of success. We also don’t have a bull nose live center. When it comes to boring, we just pray.

Our final solution after much suffering was to give in and build a steady rest, but after much time spent in other areas, we only have 5 days left. As such the main goal of this steady rest is: time (or lack thereof).

We want to be able to quickly make a good enough steady rest that we can manufacture from scratch in 5 days to face, turn, and bore a 5 inch tube that is 18 inches long. It doesn’t need to do more than that and will likely not need to endure more than half a year.

So with all that said, here is the basic idea: two 1/4” steel plates that are waterjetted with blocks (metal, NOT 3D printed) sandwiched in the middle of them. The blocks will have through holes to allow for bolts (or pins?) to join the plates and blocks together. The blocks will also have a threaded hole going in the radial direction to allow a bolt to pass through and serve as the steady rest fingers. The rest is self explanatory from the picture.

So, do you think this is doable given our time constraints? We have all the stock necessary it is mainly a concern about manufacturability and if it will actually work. How should we lock the bolt fingers in place? Assuming we put something on the end of the bolts like a bearing, does the bolt idea itself actually work? Will this design be strong or rigid enough?

Any and all help is immensely appreciated. We are relatively amateur machinists so please keep that in mind. We have access to 3 axis CNC mills, as well as a manual mill and lathe.