Part | Component Status | Responsible Engineers |
|---|---|---|
| Booster Diaphragm | Manufacturing Prep | Kevin G. 2024 |
| Sustainer Diaphragm | Manufacturing Prep | Claire J. 2024 |
Design
Requirements:
Shall connect soft goods to recovery assembly
Shall connect to the piston
Shall connect to the anti-rotation rod
Shall connect to the booster cup
Shall withstand separation loads
Shall withstand deployment loads
Material: Al 6061
Risks: Deforms during separation or parachute deployment
Features:
- Pie cuts for mass reduction
- Holes for interface with rope guide attachment
- Hole through center for piston connection
- Radial holes for interface with cup
- Single hole on one of the spokes for anti-rotation rod
Booster Diaphragm:Booster_Diaphragm_KevinG_v3.SLDPRT
Sustainer Diaphragm:
Analysis
Booster Diaphragm FEA:
- lowest safety factor: 2.14571
- fixture is at center where booster diaphragm screws onto piston rod
- force applied on lower lip: 480 lbf
Sustainer Diaphragm FEA:
- lowest safety factor: 3.06
- fixture is center tapped hole
- force on lower lip: 360 lbf
Manufacturing
Drawing: Diaphragm Booster Drawing.SLDDRW
Note: The CAD for the rope guide from McMaster is not exact- wait for the physical part to arrive and machine carefully
Operations:
Waterjet top face profile:
* Lower size of holes on the top face by 0.005’’ to account for tolerance of waterjet before
Use Quality 3
2 tabs of 0.1 width and height
Set thickness to 0.5
Set Material Al 6061
Ensure mass-saving cuts do not interfere with waterjet nozzle. If they are, pause the waterjet and remove the mass-saving cuts.
Tapping Holes
Tapping can be done using a lathe or a desktop tap. We used the desktop tap at Todd shop.
Use tap fluid while tapping.
Remember to turn 1 cycle and then turn back half a cycle. Do not continue turning if you feel a lot of resistance.
Tap the centre hole with a 5/16-24 tap to hold the cylindrical support rod.
Tap the 2 holes for the soft goods attachment using a 8-32 tap.
Tap the hole for the anti-rotation rod using a 1/4-20 tap.
Lathe and Turning Operations
Use cylindrical support rod to hold diaphragm in lathe for turning operations.
Zero x and z offset on Lathe to edge of the diaphragm.
Set go-to of x axis as the measured diameter of the part.
Set go-to of z axis as the measured thickness of the stock minus the lip length needed.
Turn in 0.02 in increments (more if you’re an expert) along the z axis until the diameter gets about 0.015 in away from the required diameter. Then, turn down in increments of 0.005 in.
Keep measuring diameter and if the booster cup is manufactured, test fit with it and remove material as needed.
Radial Indexing
Properly set up radial indexer ensuring sides are straight.
Use a cylindrical support rod to hold the diaphragm in the radial indexer for drilling operations.
Place the Booster cup over Booster Diaphragm to ensure holes will be aligned.
Check that the first centered hole is aligned so that no holes will be drilled into the spokes.
Attach the center drill tip and align the drill tip at the correct distance in order to mark the center holes.
Set the spindle speed to 1200 RPM.
After drilling the first center hole, rotate the part by 30 degrees and continue drilling center holes (12 in total).
Replace center drill tip with a drill tip and drill through all center-marked holes. Use correct drill size for certain tap size (6-32): https://pages.mtu.edu/~suits/misc/tapsizes.html
Use a tap-handle and center to tap holes on radial indexer (Refer to tapping holes section for tapping instructions)
Tap radial holes using a 6-32 tap.
Extra Notes:
Check the waterjet thickness again!!!
If you think you’re done tapping, keep going more.
Do not tap fast otherwise taps will break.
Use a lot of tap oil.
Double check spindle speed for all operations.
Double check tap size
Precautions
Waterjet
- Check thickness on Waterjet
- Ensure mass-saving cuts do not interfere with waterjet