System :: Metal Brake

How can we make it easier to produce complex parts?

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This page details the evaluation process for the system developed over the semester.

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Mini Metal Press Operator (WT)

Project Recap
1. What does it do?
• Sheet metal bending with programmable angle stops.
2. Who's done what beforehand?
• The original design for the sheet metal brake comes from David Gingery. Other compact home metal brakes have been created, such as Dan Gelbart's, which other designers have recreated, such as John Kahrs and Vineet Padia.
3. What did you design?
• I designed the mechanisms and control loop for the adjustable stops, and a modified housing and form factor to integrate them into the same machine volume as the clamping and folding mechanisms from the Gingery press.
4. What materials and components were used?
• I used the following materials, in addition to modular things circuitboards designed and provided by Jake Read and Quentin Bolsee.





5. Where did they come from?
• All hardware were standard options purchased from Mcmaster-carr or found in spare parts bins around architecture shops. Lasercut metal parts required a thickness beyond what the N52 IDC laser could cut, so I opted to send cut files and explanatory drawings to xometry to get those parts cut and sent to me.
6. How much did they cost?
• The project budget consisted of three major components:
• Xometry order of 1/4" steel lasercut parts: $297.12
• Mcmaster-carr hardware: $298.34
• Miscellaneous metals for testing: $102.00
7. What parts and systems were made?
Jake and Quentin made the circuitboards and firmware to enable modular things. I designed, assembled, and calibrated all of the metal parts of the machine.
8. What processes were used?
Lasercut steel parts, 3D printed fixtures to interface with stepper motors, stationary drill press and bandsaw for fabricating aluminum brackets from off-the-shelf angles.
9. What questions were answered?
1. Can we get enough stiffness to fold metal without using heavy-duty metal shop techniques?
• yes! Although the precedent designs for compact brakes use milled steel extrusions and welded reinforcement for stiffness, I was able to make a compact brake design using a kit of parts that could come in the mail and be assembled like IKEA furniture.
2. Can I make it easier to fold complex metal parts?
• I believe so! The semi-automatic approach is subtle but surprisingly effective. Embedding this small digital feature into an otherwise analog machine removes a substantial amount of calibration effort required by the operator.
10. What worked? What didn't?
• The clamp mechanism worked
• The adjustable stops work
• The embedded system architecture works to enable programmable bending
• The bending works, situationally.
• The clamp teeth worked, although the adjustability needs improvement.
• The enclosures I designed to house the moving parts did not work, because I did not properly constrain the linkages and moving parts are misaligned with where I expected them to be.
11. How was it evaluated?
I evaluated the clamping mechanism by tuning the machine tolerances until I could securely clamp a piece of paper. I evaluated the folding mechanism by using shims to adjust the machine parts until I could successfully bend a sheet of metal. I attempted to fold different thicknesses of steel and aluminum, and so far, the highest gauge I have been able to bend has been 1/32" aluminum. I expect that the machine has higher capacity, if the offset and alignment between the clamp teeth and bending leaf pivot are carefully adjusted.
12. What are the implications?
It's not necessary to automate everything to implement some practical functionality in an otherwise analog process.
Architects could hypothetically send digital instructions directly to machines to simplify the need to produce paper drawings.

System Demo

Once the machine was suitably calibrated, I could create some simple test parts and test the performance. Panel design and photography were in collaboration with Inez Ow.

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Next steps

1. I want to revist the IMU implementation to try using a BNO085, to see if I can get any sort of stable angle measurement.
2. Redesign the clamp leaf to simplify adjustments. It needs to be faster to adjust the positioning of the teeth to be practical.
3. Increase the stiffness of the clamping and bending leaves, toward increasing the possible gauge we can bend.
4. Eventually, I want to incorporate laser guides as I conceptualize in Component :: Part Positioning Guidance System

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