Assembling Quantity with MacroFab Hack Chat Transcript

A event log for Assembling Quantity with MacroFab

We'll be talking about large quantity electronics manufacturing and assembly in this chat.

ShaynaShayna 01/12/2018 at 20:080 Comments

Stephen : Alright, let's get rolling. A BIG hello to @Parker for joining us today

Parker : Howdy everyone

Stephen : @Parker, why don't you kick this off by giving us an introduction of who you are, what you do, and what you're excited about sharing with us today?

Parker : ok

Parker : I am Parker Dillmann, co-founder, lead electrical engineer, and podcast host here at MacroFab.

Parker : I help drive the development of our website and guide our customers through prototyping and production of there products.

Parker : Also run the blog where i put my personal projects.

davedarko : uhhh, Game Boy projects :)

Parker : I guess today we are talking about production manufacturing and assembling for electronics.

davedarko : nice :)

Parker : But I am game for anything :)

Mike Szczys : Oh man, I never put it together but I've been a fan of longhornengineer forever. Thanks for all your work on those articles!

Parker : Thanks!

Fred : i'm over here thinking how do you even get into all this?

Stephen : Awesome stuff! Let's get the questions rolling. First one:

For someone who is new to manufacturing, what is the process for a first time manufacturer?

Parker : If your product is new. The most important thing is vetting what you are manufacturing.

Parker : It sounds simple but making sure the process in building your product is repeatable

Parker : This includes part sourcing and the test procedures

Adam Demuri : Could you provide an example of where NOT being careful with that has caused problems for you?

Parker : So making sure you build the first article of your finalized product before rushing off to build your production run is important

Stephen : What best practices have you found for making sure your process is solid? What are the common pitfalls people miss their first time manufacturing?

Stephen : Along with @Adam Demuri 's question - when have you ignored this advice and what were the consequences?

Hyr0n : Dont try and source "new" parts right when they come out if you need hundereds / thousands of them. Especially during the Chinese new year. Not enough supply, the transit is slow, and youre in competition with big vendors (e.g. Mouser, Digikey, etc..)

Parker : Sure @Adam Demuri. I have worked with projects that had a very accelerated time schedule. The product was a already a "mature" product but they where switching manufactures.

Parker : And what happened was there was some design documents that was not captured and sent in.

Parker : It pertained to having some through hole parts that needed custom standoffs

Parker : In the end it required lots of rework to remove those parts and resolder them. If a first article was built first this issue would have been caught on unit 1 and not after the first batch.

Parker : The best practice is to do a mock up production run

Parker : Common pitfalls of first time production runs that I have seen?

Parker : Trying to use non authorized dealer sources for parts or eBay sourced things. LCD screens tend to be popular. :)

Jarrett : Are there any decent authorised or reliable LCD suppliers? Digikey stock is expensive and terrible

Parker : Ah another one is changing the Bill of Materials due to a problem mid run.

Stephen : By a mock up production run, are you talking about a small scale production batch?

Parker : @Jarrett I have used buydisplay before with great success

Hyr0n : If you buy screens from Ebay/AliBaba/cheaper sources...try to buy your entire lot. You can order the same thing twice and get completely different pinouts

Parker : Or talking directly with a LCD supplier.

Parker : @Hyr0n or different color hues ect ect

Hyr0n : yeah

Hyr0n : u get what you pay for

Parker : @Stephen Yes and no. Depending on how many units.

Hyr0n : hence if u go that route, buy them all at once, so at least you can tweak your drivers to accomodate the imperfections or changes in that lot

Parker : Say you are doing 10000 units. It is probably wise to do a single first article. Then do a batch of say 100 units. Then run the 10000.

Andrew Sowa : color binning is a long rabbit hole of pain

Parker : @Andrew Sowa and some LED manufactures just use the same part number :X

Parker : for all the bins

Stephen : Next question from the event discussion: Are you (MacroFab) able to purchase parts from sources (e.g. small chip company with their own web shop only) other than big distributors or would I need to drop-ship those to your location? Are there import duties to pay if that company is outside the US?

Parker : which makes sourcing parts not so much fun

Andrew Sowa : It's been getting better. Some breakout 3-step or offer it standard but it was bad 2+ years ago. Take all 16 bins and deal with it.

Stephen : Thanks @MagicWolfi for this question!

Parker : For prototype orders we will only purchase from the major distributors. For parts not available that way you can consign the part and either ship it to us or have that company drop ship it to us.

Parker : Now for production orders we will purchase parts from other places for you if you want us to.

Sea Slug Labs : How can we save on cost, with contract manufacturers.. is it cheaper for me to BUY the parts and send them to you... or for the CM to source them?

Stephen : @Sophi Kravitz question mashed with another @MagicWolfi question: How do you figure out the quote to the customer - is it per square inch of PCB or some other way? Can I get a quote (without part costs) without uploading a design, based on board specs and number of components / pads?

Parker : I do not know about other CM's but It is usually easier for us to purchase the parts verse having parts shipped in from the customer. We charge a fee for shipping in consignment parts since we have to count the parts and inventory them. Insurance on the property and all that stuff.

Parker : Our PCB pricing is per sq inch rounded to the nearest inch

Parker : plus the addon fixings like impedance control, colors, different thicknesses which are a flat fee

Parker : Right now there isnt a price calculator for our website. The pricing is a bit more complex then a simple calculator could provide.

Stephen : Very cool! I love it when the pricing is easy to understand.

Stephen : Question from @Clayton G. Hobbs: How does your software determine the labor cost for a given part? Obviously you can't know a value for every MPN, so I'm curious as to what the heuristics used are.

Parker : It is usually faster to just dump the design file in then to fill out a calculator

Parker : We split it up on two fronts. Through hole parts and Surface mount

Parker : and then on that it is based on pin count

Parker : So a SOIC-8 costs less to place then say a TQFP-144 :)

Clayton G. Hobbs : Ah, makes sense! I guess that's why one time when it thought an SOT-89 had 89 pins the assembly cost looked awfully high. :P

Parker : We also have house parts which are jelly bean style resistors and capacitors that place for free. We try to push people to use those since they are already on a feeder and really reduce our work load

Nicolas Schurando : Are trough part more expensive than surface mount? What about hybrid usb type-c connectors for example?

Parker : @Clayton G. Hobbs yeah! we are working on some exciting new software to hopefully improve our pin count and part type detection :D

Nicolas Schurando : And do you charge extra for smd components on both sides?

Parker : @Nicolas Schurando Yes through hole is more expensive. SMT connectors that have mounting tabs that are through generally get marked as SMT. We try to do paste in hole for those to reduce how much time we spend soldering

Parker : We do not charge extra for SMD parts on both sides

Stephen : Question from @Jarrett : Do weird component angles cause difficulties or more effort than standard 0 or 90 degree rotations?

Nicolas Schurando : Thanks ;)

Parker : Since our process involves batching lots of orders together the manufacturing process assumes every panel will be run double sided.

Parker : No they do not cause any problems

Stephen : @matt.liberty question: How do I make sure that the part centroids and part rotations in my Eagle design matches what you need for assembly?

Parker : The pick and place doesnt care what angle you have your part at.

Stephen : Another question from @Nicolas Schurando: I have a practical question. A project that I am considering for manufacturing uses a tiny 96x16 oled display that I source from aliexpress/buydisplay. The contact with the board is done via fpc soldering, and there is no connector available with the pitch. Furthermore, the oled display as with most I assume is not compatible with oven soldering temperatures. How would MacroFab handle that? Does it provide hand soldering for those special parts? Would the fact that the display do not come in a tray of a cut tape be a problem?

Parker : That one is good. On part centroids, most manufactures will have how the part sits in the tape or whatever packaging it comes in.

Parker : I usually look at that when designing parts and then put the center in the middle of the case package

Parker : On part rotations, IPC-7351

matt.liberty : Makes sense. What happens with your process if the design files find an incorrect part rotation or placement? Do you do any checks?

Parker : pin 1 should match how the part comes off the packaging. But sometimes you do not have this information.

Parker : So making pin one the "upper left" should suffice.

Parker : We have an order review process. If we can't figure something out then we will contact the customer

Nicolas Schurando : @matt.liberty Actually, there is an interesting article on hackaday blog about part centroids and orientation,

Jonathan Herbst : Can MacroFab handle super tight pitch bga parts like nFBGA.

matt.liberty : Thanks @Nicolas Schurando!

Parker : @Nicolas Schurando in the past we have hand soldered those screens

Stephen : With 7 minutes left I have one more technical question before ending with a fun one. This is from @Hyr0n : From a scalability time consuming issue of programming hundreds/thousands of boards, is there a certain type of programmer & physical interface you prefer (over others) if you are programming the boards after fab? (e.g. Pogo press on, SWD 10 Pin, 20 pin, etc...)

Parker : So the pricing would follow through hole rules even though its a "surface mount" part :)

Parker : We don't really have a preference for programmers. But on the physical part is very important.

Nicolas Schurando : @Parker Thanks!

Parker : For lower volume stuff having either a proper connector, tag connect style cable, or a single unit pogo pin fixture are the best

Hyr0n : Like last year, at the end we went with a 10 Pin SWD (super small), realized that sucks. and we only did a few hundered

Hyr0n : coo thx

Stephen : A fun final question of the hour from our @Andrew Sowa : Have people contacted you for problems with other people's boards since you put your logo on them?

Parker : Well @Hyr0n that was cause the solution to programming those was sticking in a male header and leaning it over :)

Parker : which works till it wears out

Hyr0n : i got really good at that

Nicolas Schurando : @Parker In reaction to @Hyr0n 's question, does MacroFab provide post assembly programming?

Parker : for high volume products building a proper pogo pin fixture that can program and test multiple boards is a must

Parker : Yes we do @Nicolas Schurando

Parker : @Andrew Sowa hmm that was an experiment we ran for a couple panels and our customers didn't like it so we stopped :)

Dave Blundell : I asked in the comments but this is real quick one... How much leader do you need on used reels to avoid wasting parts? 6" 12" 18" ?

Parker : @Dave Blundell 1"

Dave Blundell : wow!

Parker : our Mycronic is very efficient for cut tape parts

Nicolas Schurando : @Parker I'm asking because I don't recall seeing it mentioned on the website.

Andrew Sowa : Guess I have a collectors item then

Dave Blundell : nice. I have a bunch of designs I've done protos of that are getting ready to come back to you for small production runs.

Parker : @Andrew Sowa yeah we thought it would be a good idea and it wasnt hehe

Fred : I've sat through and screenshotted the whole Q&A for further study, so many abbreviations and stuff but it was really helpfull in learning new things about PCB manufacturing!

Parker : @Dave Blundell yeah our overage calculations basically make sure there is enough leader. Like if you are ordering a single prototype with a single resistor we will get like 10 of them.

Dave Blundell : Macrofab are great to deal with. I've only done a few small runs with them but I was really impressed with their knowledgeable and rapid customer support.

Parker : instead of needing 100 :)

Stephen : A BIG Thank you to @Parker for joining us today.

Parker : It was a lot of fun. I love talking about this stuff.

Shayna : Thanks @Parker !

Stephen : Really really awesome getting to hear about what you do, how we can get started, and throw our tech questions off your sounding board.

Nicolas Schurando : Thanks again @Parker .