Regular Member Meeting 2014 04 08

From HacDC Wiki

Time and Location

April 8, 2014
Called to order at ____ by _____.
Members present:
Others present:
Quorum met?

Approval of Previous Meeting's Minutes

Annual Meeting 2014


  • Everyone involved in moving the Scanning Electron Microscope!
  • Ben Mendis (sitwon) and haxwithaxe for truck driving!
  • Zach for improving CNC mill, Laser Cutter, and 3D printer functionality.

Director Reports

President's Report

Vice President's Report

Treasurer's Report

Here is the financial summary spreadsheet for March 2014: File:HacDC Financials 2014 03.pdf.

Project Awesome

Here is the Project Awesome spreadsheet for March: File:HacDC PA Projects-2014 03.pdf.

Secretary's Report

Director-at-Large Reports


We moved the SEM! It was quite an adventure and I'd like to thank everyone who helped us out with this.


Project Awesome Reports

Project LASER




Still healthy and stable. Willing to reimburse some SEM repairs, though at least a few hundred dollars need to be maintained as a reserve. This month's expenses include:

  • $57.95 Dial Test Indicator (Used to level the CNC mill.)
  • $20.47 Air dusters (General purpose and SEM cleaning supply.)
  • $100 in filament from Microcenter.
  • ~$10 LetraTag Material for Label Maker (projected)
  • $80 in SEM supplies (projected, may need to wait for next month)


There have been no objections raised to purchase of a small vertical bandsaw like this one for less than the existing $145 budget:


This should be at least as usable as the last bandsaw. Given our present financial situation, I think we should just get something suitable for cutting CNC mill/laser cutter stock rather than seek a more expensive machine.

If there are still no objections, will select the best one within the current EXPANSION budget, and direct Katie to order it. Preference will be given to support for cheap, standard blades.


Member Reports


Prusa Mendel

Was on the fence for a while what to do about this beast. After approximately 300 hours of work, there was every reason to expect the last maintenance cycle would be the last. However, multiple spontaneous failures now cast any plans for long-term stability into doubt. Even if we actually did stabilize it, the effort would be sunk into a slow (45mm/s vs. 300mm/s) machine with ever-present alignment issues. First-layer alignment in particular has been particularly difficult to maintain to any reasonable degree. The non-linear surface has been estimated as a 6th order problem.

Current state of the art designs are likely more than an order of magnitude better, using a 'delta-bot' configuration and highly rigid construction from aluminum extrusions. Such designs are not subject to many of the fundamental design flaws our Prusa Mendel suffers:

Recommend we either purchase one of these, or direct our efforts away from 3D printing for until we are ready to fully polish off our own designs (eg. Optical Table, Flex Replicator, etc).

Biosignal Amplifier

As a reminder, fully operational and documented:

Photolithography PCB Fab

As a reminder, fully tested, working, and documented:

Need to create a 'photolithography materials' box to keep the equipment organized and available.

SEM Progress

Organized the wiki pages and began research on replacement electronics. Looks like we need an FPGA managing a bunch of I2S ADC/DAC devices typically used on high-end 24bit 192kS/s soundcards. Have already thoroughly investigated the FPGA toolchains, and HacDC should have already have some usable FPGAs to begin experiments.


Nearly there, another HacDC member has the final Giant Fresnel lens. Projector construction can commence once lens has been retrieved.

Imagnus, Flex Replicator, Optical Table

Still in the same state as last meeting. All in progress.

Unnecessary Mess

Spent >3.5 hours cleaning up work benches at HacDC. Some of the more egregious problems included a melted space heater plug, still plugged into a power strip, and a messy chemical spill. In all cases, the responsible parties could have cleaned up much more easily before leaving.

This does not concern any new items showing up at HacDC, nor project SEM, and probably not any other ongoing activity. Looks like someone using the space couldn't bother to put tools back where they came from or clean up after their mess. Seriously, who here feels comfortable leaving the space with a chemical spill on a work table to harden into sticky residue for the next user? Since I don't know, I can only politely request it not happen again.

This also goes for anyone administrating HacDC events - please watch your guests.


Literally just disposing of the sheer quantity of e-waste is a problem, owing to past inability to dispose of junk more frequently. Failing other options, Waste Management 'dumpster in a bag' is a possibility, at a cost of approximately $200 (not recommended).

Old Business

New Business

Allocate $x to purchase of a new 3D printer, where $x is $0-$1450 depending on the type of printer decided upon.


In order to move the SEM I rented a truck and drove it down to Norfolk and back. I would like to get reimbursed the $724.94 for the truck rental.

New Members


Adjourned at ______.