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Confirm or deny rev G chassis and rec C chassis cover changes
Closed, InvalidPublic

Description

Weiser requested changes to the chassis flanges which required changes to the chassis and chassis cover. The chassis was also modified to include masking under the USB mount

Event Timeline

Steven created this task.Nov 16 2018, 12:40 PM
Steven triaged this task as Normal priority.
Steven created this object with edit policy "LulzBot Hardware Products (Project)".

@jessica can you please update here once you have expected delivery of the rev G chassis and rev C chassis cover?

west added a subscriber: west.Dec 11 2018, 11:43 AM

Wouldnt the new chassis have different results for EMI since the flange gap would be bigger?

tutley added a subscriber: tutley.Dec 12 2018, 9:36 AM

@west frequency = speed of light/wavelength

for radiated emissions we test between 30 MHz and 1 GHz. This means the wavelengths vary from 10m(30MHz) to ~.3m(1GHz).
A general rule for a faraday cage is there should be no holes larger than 1/10th the wavelength you are trying to contain/keep out.
This would mean we cannot have any holes larger than 30mm. I do not think the changes to the sheet metal flanges will leave us with a larger than 30mm hole.
Also there are already some 40mm slots in the bottom of the chassis that are for air flow, and these will likely be a bigger EMI leak than the changes to the sheet metal will be

My current understanding is that the vendor who requested these changes is no longer going to be a supplier for this project at this time. Another supplier has just sent samples of a different change they requested, which did not include the changes this ticket is for. As far as I am aware, the changes in this ticket are not necessarily beneficial to the suppliers we are proceeding with. We may want to kill this one, and then figure out the version weirdness this has created, as the documents from this have been sent out and could cause confusion if we have another rev G. For instance, T4495 was also labeled as rev G, because I had forgotten about this.

does this ticket need closed as it is no longer valid?

samantha closed this task as Invalid.Jan 8 2019, 10:57 AM

@jessica I was gonna ask you the same thing. Sounds like yes. Closed