Thermoformer Adapter
- Divit Gawri
- Christopher Arzoumanian
- Camilo Artigas Alos
- Smile Khatri
Big Project | Project | Project Manager |
|---|---|---|
Pegasus 2 | Waterproof Dome | @Smile Khatri |
Task Description
Design and develop an adapter for the thermoformer so that the vacuum can connect to it. Should fit a thermoformer and vacuum.
Context:
To allow airflow from the thermoformer into the vacuum. The pressure of the vacuum should be used to suck airflow from the thermoformed and therefore the system should minimize pressure loss to the atmosphere. High wall thickness and high infill can be used to minimize air leakage.
Have a vacuum and inlet for the thermoformer to be used. Recommend a outer fit (the adapter fits around the inlet and vacuum pipe on the outside/od)
Dimensions to consider(should add slight clearance to adapter design):
OD of vacuum outlet: 65.5
ID of vacuum outlet: 57.75
OD of Thermoformer: 37.75
ID of Thermoformer: 34.75
Constraints
Constraints | Written By | Append Date |
|---|---|---|
Should minimize pressure loss | @Divit Gawri | 2025-03-20 |
Should be a good fit for the vacuum and thermoformer | @Divit Gawri | 2025-03-20 |
3D Printed with flex seal coating | @Divit Gawri | 2025-03-20 |
Design completed by Monday, March, 24th. | @Divit Gawri | 2025-03-20 |
Relevant Contacts
Subteam | Contact | Contact Description |
|---|---|---|
| @Divit Gawri | Discord |
Assignees
Assignee | Asana Task | Date |
|---|---|---|
@Christopher Arzoumanian |
| 2025-03-20 |
Task Progression/Updates
Author: @Christopher Arzoumanian Date: Mar 25, 2025
Made adapter using outer diameters of connections as recommended
Used 70 degree angle taper, and 8.75 mm wall thickness for minimal pressure loss
The inner-diameters of the adapter (that are connecting to the thermoformer and vacuum) were made 2mm bigger than measured values for tolerance. Is that too much tolerance?
- As shown below, I took the measured 65.5 mm and 37.75 mm dimensions, and added 2 mm to each for tolerance.
Author: @Smile Khatri Date: Mar 25, 2025
I like the 70 degree taper to minimize pressure and flow recirculation
Is the dimension labeled in the third picture incorrect? I think 39.75 should be the ID in that pic. Does the adapter slide over or inside the thermoformer outlet?
If you made the diameter 2mm larger than the measured diameter of the ports, then that leaves 1mm radial clearance which is too much. You are going to get a vacuum leak, and air can enter into the adapter through that gap easily. This basically makes the vacuum weaker
I would go much tighter on the clearance, and try to achieve a tight fit so that it is sealed, and there is no extra air entering the vacuum. Maybe ~0.3mm clearance (any tighter will be tough to achieve on a 3D printer)
I am 100% sure the adapter won’t be air-tight (meaning no air escapes/enters the adapter) because it is impossible to manufacture a perfect circle, especially in 3D printing. In industry, an O-ring is used to seal concentric parts.
For this application, we could try sealing any gaps with vacuum sealing tape. I can’t predict how bad the vacuum performance will be, but I am pretty confident you’ll need to seal any small gaps.
Author: @Christopher Arzoumanian Date: Mar 27, 2025
The dimension labeled in the third picture of my previous update was incorrect. I’ve changed it accordingly (but we have new dimensions now)
I’ve made the diameters 0.6 mm bigger than their measured values, leaving 0.3 mm radial clearance.
I’ve kept the walls in the same place, so now they’re a bit bigger than before: 9.45 mm
Should I make a slot to fit an O ring?
Here are the new diameters:
Author: @Christopher Arzoumanian Date: Mar 31, 2025
We 3D-printed the adapter, and the thermoformer end seems to fit well
On the other hand, the vacuum has an extruding rectangular portion which was not accounted for in design
I’ve redesigned the adapter accordingly as shown in the pics below
