Wednesday, July 22, 2015

A tour of Small Batch Assembly

Company logo on the orange walls
Recently I had met up with Bob Coggeshall at the inaugural National Maker Faire and he invited me to stop by the factory sometime in the future. I wasn't out in the general Reston area for a while until there was a conference over there. Sent him a tweet, and the following day drove over through the rather nice technology district.
Arrived at NOVALabs where he is co-located and had a look around before I found his factory in one of the hallways. After hellos he showed me around the factory. The immediate attention grabber(aside from the international orange walls) was the pick and place machine from Manncorp. It sports full machine vision and 64 possible feeders in addition to auto-swap vacuum heads. Bob walked through the setup procedure and showed how to get the machine vision tuned for maximum accuracy by using none other than MS PAINT to edit a captured bitmap which is used to train the vision system. A fascinating tidbit I learned was that the software was built on layers of previous updates on the foundation from the 1980s and has been continually updated for compatibility and feature-adding such as recently being Windows 8 ready[So long WinXP!]. To streamline and increase production efficiency, Bob uses a custom written barcoding software named "Barcodatron" which allows him to set barcodes for each client's parts. It is an additional verification of parts being correct which further reduces waste due to screw-ups. This software is available on Git being open source. If you do not have all the parts, Bob does have some on hand that can be added for a small premium. Next up was the stencil and solder paste application station which had a lot of lessons learned and money lost. Originally, he was using Kapton stencils as they are cheap but cannot do fine pitch components such as TQFP or BGA. After that, steel stencils in frames were the way to go but that needed a $1500 hinged jig. Interestingly enough, that did not work out too well and a cheap fabricobbled holder of scrap acrylic and PCBs (total cost around $20) worked MUCH better than the vastly more expensive jig which became a support for the fabricobbled unit. The solder paste is stored in a 12v mini fridge commonly used for cars as a portable beverage cooler, to prolong the life of the flux that keeps the paste a paste (feels like cold peanut butter). After that was the rework and hand soldering bench, which was the biggest single chunk of the entire factory. Sporting not one but two soldering irons and hot air guns in addition to a preheater, powered vacuum pen and an IR thermometer. One of the useful non-tool units on the bench is the timer power bus, which shuts down the irons and air guns after a certain amount of time as not only a safety feature but also to prolong the life of the units. Bob highly recommends purchasing one of the the cheap air rework stations with an iron built in if you plan to do any kind of SMD work (I am going to be purchasing one soon), well worth the low ($50USD) price [might want to check the earthing in there though]. Finally he showed me the reflow oven, which was a SR325C unit (only differences are the PID controllers) that was not of iffy quality as so many cheapo ovens tend to be. Flux cleanup tends to be a bit of a pain, regardless if it is "No Clean" (he still hasn't found a good flux that doesn't need cleaning yet), the real trick he uses is to clean with Isopropyl alcohol and THEN windex for best results. While discussing projects (and accidentally giving him a LOT of new ideas to add to the backlog, whoops xD) he invited me to teach SMD soldering classes at NOVALabs sometime in the future as I already have the skills and I agreed to help out once I figure out transportation. After the factory tour I was shown around the NOVALabs hackerspace. It has quite a hodgepodge vibe to it, in comparison to the clean(ish) and organized atmosphere of TechShopDC. Partially completed projects and machinery under repairs were scattered around the main room, where a currently inoperative multi-axis CNC mill sat in a corner behind a programmable loom from the 1970s. I forgot to take pictures of the hackerspace, sorry for the lack of images, will be amending that next time I stop by! This was a FANTASTIC experience providing an in-depth look at a local PCBA factory and an excellent opportunity to talk to a fellow tinkerer about projects and ideas, thank you for the awesome time Bob!

Looking into the factory, intern at the back

Racks of parts and feeders (theres a few boards stashed around too)

Barcode system "Barcodatron"

Barcoded feeders

Close up of pick and place bay

Wide shot of bay

Machine vision learning

Ye olde splash screen

Hackablinky panel

Bag of Hackablinkys ready for shipout

Pogo pin programming jig

Geppetto Electronics USB ┬ÁISP assembled and used at Small Batch Assembly in the programming jig

$20 stencil jig that outperforms the $1500 unit it sits on

Placing panels

Hackablinkys ready for stencil

Solder paste in a 12V minifridge (feels like cold peanut butter)

$50 soldering iron and hot air gun (VERY useful and good quality)

The rework/manual soldering area

The reflow oven

PID controller

Found a Stickvise!

Fluxes (Bob's tip: use windex after isopropyl cleaning for best results)

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