Our very own DMS members Andrew Falgout (@Andrew_Falgout) & Mike Eber (@nikropht) have donated a tabletop Pick & Place Machine, Dengxin Tech TM420A, Stencil frame and reflow oven.
Using it will require training but we will work on a sample DMS badge project soon to get it setup.
Please send them your thanks for such a generous donation!
When will there be training?
yes
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There is something disconcerting about someone responding to their own post…
So this thing… is like totally kewl!
Official Product Page (I think… if it’s not in English, you can click “English” near the top… 
)
http://www.neodentech.com/bbx/996360-996360.html?id=26798&pid=761183
One of their many demo vids:
Where to see more of their vids:
Anyway… I’m sure a lot of members already knew what it was; but, I didn’t 'n now I do ~ w00t! It’s pretty neat to see the strips of surface mount components being used as intended… I’d sort of wondered how they worked… ('n now I know that, too! w00t w00t! 
)
Thx for the donation, y’all! 
I got a chance to check this stuff out today. The pick and place works great. Here’s a poor video of it placing some 0603 resistors: Cloudup
I left a reel of resistors attached to it in case anyone else wants something to test with. I don’t need them back but DMS probably doesn’t need them either so I’ll make sure they don’t hang around forever.
I may return tomorrow and see about trying some real boards with it, and maybe get some better video of it in action. After that I’d be open to training people on its use.
I’m happy to report that I did about 50 boards yesterday with great success! The reflow oven was considerably disastrous, but the pick and place machine was brilliant. It took me most of the day to get everything figured out and set up and adjusted, but after that it was popping out boards faster than I could reflow them even if the reflow oven had been working properly.
Apparently the oven is known to have a hopelessly unforgivable design oversight (the thermocouple lacks cold junction compensation) but it’s popular enough that a fix already exists which I believe we’ll want to implement. It involves adding a temperature sensor for the cold junction and flashing a rewritten firmware, which is great because the factory firmware sucks badly, particularly with regard to button input polling. You do often have to push a button several times before it works. As for the cold junction compensation, it works decently well for the first run but you need to make sure to let the internals cool down to room temperature before another run or else the temperature will read artificially high and your solder may not get hot enough to melt. I had to run a couple of batches through twice, and I ended up bringing the last few boards home to reflow them once I realized I needed to wait 20+ minutes for the cold junction to cool each time.
The pick and place machine was much more pleasant to work with. Aside from some metal burrs on one of the feeders interfering with tape movement (I filed it slightly and it seems resolved now) I didn’t find any problems with it and it seems to be functioning as intended. It’s china’s cheapest so the firmware is indeed riddled with bugs, but you quickly learn which operations cause a crash (for example, loading a file but then canceling before starting it) and then it’s not so bad. It doesn’t crash while simply running, so it doesn’t interfere with actual operation. You just have to be prepared to power cycle it whenever you do something that makes it stop responding to input because the person who spent five minutes writing the firmware didn’t anticipate that you’d do that.
Quite an unusual number of people popped in to the electronics room to check out the pick and place machine while I was running it, perhaps unaccustomed to hearing stepper motor sounds emanating from there. I fielded a number of questions throughout the day, most of which were asked repeatedly, so I’ll go ahead and post the answers to those common questions here in a bit.
Many thanks indeed to Andrew and Mike for this donation. This thing did in one day what would normally have taken me four, and that’s including the time taken to learn how to use it. That means more time for new projects, which is what life is all about of course! I’m certain this will help attract new members, and I’m excited to break existing members of the surface mount phobia so they can start using it too. This thing is perfect for maker-sized production runs of several to hundreds.
I’m certainly confident about training people to use the pick and place machine now, although I don’t really know how training at DMS typically works. Perhaps it would be appropriate to start a thread to gauge interest for a training class? A lot of people showed interest in it yesterday and some asked about training, but I wonder if most members would want to start with general surface mount classes before having any need for pick and place training. Still, I’m eager to pass on the knowledge I’ve just assimilated.
I forgot my camera so here’s some more phone photography. The second video shows a whole board from start to finish at standard speed minus the pushbutton which is too tall for the feeders. For size reference, the resistors are 0603.
@benemorius thanks a lot for being the first victim Sorry I should have warned you about the oven. Didn’t know you were populating boards yet. How was it for parts in strips and not on reels? BTW, what were you making? I see the words VEHICLE, PWR and IGN on your solder mask.
Get with me on training and/or classes. We would be happy to fund boards and parts for this. I was thinking of a DMS Maker Badge in SMD & Through-Hole versions. Thought it would be nice to compare the difference of each approach.
Maybe we can coordinate with classes on board design/layout and source the BOMs.
I need some clarification from someone who has the authority:
Pick and Place machines are for mass production of circuit cards. One of the rules at DMS is no Large production runs with the intention to sell. The Pick and Place machines exist for that sole intention. Did I misunderstand the rule, or will there be an exception made for those of us who use the Pick and Place???
Also, if there is training to use it, sign me up. I intend to use the PnP machine for a number of projects. 
…X…
“One of the rules at DMS is no Large production runs with the intention to sell.” No such rule exists the general rule of thumb is Be Excellent. For example if your working on a long project and someone needs to use a machine get the person in so they can use the machine. As well as don’t leave any machine in a state that the next person can’t use it immediately.
This is one of those things we don’t want to make a rule if we don’t have to, the expectation is to play nice with others.
FYI here are the Rules
https://dallasmakerspace.org/wiki/Rules_and_Policies
To be clear, you really wouldn’t want to do mass scale production with equipment like this unless your boss said you had to. I could see doing up to a few hundred if they’re small enough that each panel has a couple dozen boards on it so you’re really only doing a few panels, but an actual large production run would not be pleasant or fast especially considering the small size of the reflow oven.
Some rough math based on the speed of the pick and place and the size of the oven says that doing thousands or tens of thousands would actually tie up the equipment for multiple days and that would not be excellent if someone else is waiting to use it. A multi-day run would be especially unpleasant anyway due to having to setup and remove your reels each day. This is a very time consuming step since this machine has integrated feeders instead of detachable ones you could bring from home. Similarly this setup time also imposes a minimum practical limit of several boards or else you’re spending more time setting up the pick and place than it would take to just place parts by hand.
As Chairman of Electronics, it would make me very happy to see us get a lot of use for the pick & place machine. It is a great tool for us and we have to thank @Andrew_Falgout & @nikropht for it. As long as people are not hogging it or breaking it we will be fine. As @Robert_Davidson said, just be excellent to others and you can use it for short run production.
I want to support @benemorius in learning it and his passing that knowledge onto others. Electronics intends on having classes and some basic materials available to support that goal. If you have ideas for a very basic project idea let me know. It can be a simple blinky badge or something practical like a USB charger.
In terms of ideas for a project to use in a class for learning the p&p and reflow, I would suggest a DMS badged version of one of the Arduino’s. The nice thing is the schematics are already available, so it would just be a matter of creating the board (with DMS logo) and then the manufacturing files. I bet these would be very popular as well!
Yes we would need to improve the reflow oven situation. We can “upgrade” the current one or my preference would be to get something more suitable.
It would be seriously cool to offer DMS branded Arduinos. But I think something much simpler is in order first. Something we can offer for a buck or two on tour/demo nights.
Well if we did one of the Arduino mini’s that remove all of the USB communication and rely on a FTDI programming/communication header, you are down to just a few parts and a single sided board that is small enough to be a 24 pin dip.
I have a Arduino mini pro in front of me, and not counting headers (which the people who buy them can solder in), it only has 14 parts, has all components on one side, and the board is only abt 1.25" x 0.7" I am guessing that in reasonable quantities we could buy the parts for $4-$5 and these boards retail for $10, so we could either sell at parts cost, or add a little to cover labor costs (if the rules allow).
I understand that this is a little more complicated then you were thinking, but I think these boards would be a great public relations piece. We could get them written up in Hack-a-day, Make magazine, etc… As the largest maker space in the country we don’t get the coverage we should for all of the cool things going on here.
I can tell you from personal experience with the reflow oven, the thermals
are NOT consistent across the entire board, and you need to place something
on the edges to allow the heat to flow around it. And even then, you MIGHT
need to do some spot heating to “force” things to reflow. I’m VERY happy
it’s in use.
./Andrew Falgout
KG5GRX
Using cut tape instead of full reels worked very well actually. I just had to attach a few inches of leader tape to each one. You end up needing to empty about 40mm of parts (that’s 10 0603s at 4mm spacing) for proper installation and then you need at least several parts worth of tape installed for it to feed properly, so there’s a practical minimum limit here as well.
I didn’t actually expect to populate real boards so soon either, but the first day went so well and at some point the line between doing a full test on a board and actually making real boards becomes blurred. Once I had gone to the trouble of setting up all the reels, I didn’t care to stop until I had run out of boards.
The board I was making is a diagnostic interface for older BMWs: Tiny ADS Interface - openlabs.co
This was my experience also. I believe the replacement firmware can run the fan at low speed during heating and I expect this would help considerably with heat distribution.
I’m rather fond of this oven so far as well. My reflow toaster has a slightly bigger working area and much improved visibility, but I really enjoyed not having to worry about opening the toaster door to ramp down the temperature.
Thank you for the clarification.
This example you provided gives much guidance, as to how one is expected to use the PnP. Thank you @Robert_Davidson ; @Lampy.
During one of the open houses, I remember distinctly hearing the tour guide stating exactly that: No large production runs with the DMS tools, if your intention is to sell. The way it was stated, it sounded like this was a rule. Though I had read the rules, it sounded official enough not to question it.
Again, PnPs are a PITA to set up for a hand full of boards, but excellent if you have dozens to hundreds to manufacture - even with the restrictions the one DMS recently acquired. And I do plan on using it - just the thought of t makes me giddy.
On that note:
It is AWESOME, an a Massive allure to potential members, to have tools like the PnP at DMS. Tools that most of us could not justify to own, but would love to use from time to time.
…X…
Here are some answers to some common questions I received the other day about this stuff. Sorry this post ended up being rather long, but I ended up repeating everything here at least several times to different people so there’s an evident desire for this information.
There are 3 parts to the process of populating boards with this equipment, represented by each of the 3 things donated. The pick and place does the part placement but that’s only step 2.
First the stencil machine is used for applying solder paste to the PCB. It’s made to be used with framed metal stencils, which are more durable and more expensive than the DIY-style plastic stencils like you get from oshstencils. Unless you have a metal stencil in a frame, you don’t need this stencil machine. Metal stencils have recently become much more affordable from china, but plastic stencils can still be easily good enough for hundreds of boards.
After the paste is applied, the pick and place machine is used to place the parts. It only places surface mount parts with a height no greater than 3mm. If you have taller parts or any through hole parts, you’ll have to do them by hand.
Once the parts are placed, the reflow oven is used to reflow/melt the solder paste. The time between applying the solder paste and reflowing should be kept under a few hours or else the paste will become dry and the solder will not reflow well. You don’t actually have to be as delicate as you might think when transferring your board from the pick and place to the reflow oven. The paste is a little sticky and most surface mount parts mass so little that even dropping a board won’t necessarily send parts flying.
It does place parts well, but getting it to do so is not necessarily effortless. The main thing to know about this model is that because it lacks a camera for vision centering, so you have to dial in the feeder offsets for each of your reels so that it picks up your parts as close to their centers as possible. From my two days of experience with it, I’d say it can place 0603 or bigger with little or no feeder offset adjustment if you’re prepared to fix some of the part placements afterwards, but for anything smaller or for runs of more than a few boards, you’d probably want to spend some time dialing in the offsets. The smallest part I tried was SOD523 (it’s about like 0402) and I was able to get good placement fairly consistently after a few iterations of adjustment. It’s rated to place down to 0402 and I find that believable.
It uses vacuum to pick up parts and can hold up to two vacuum nozzles at once. The reason for multiple nozzles is so you can attach two different sized nozzles, but also you gain some time efficiency by picking up two parts at once. To get good results, you need to make sure you’re using the right size nozzle for each part. There are 4 different sizes and the machine can hold 2 at once. If you need more than 2 nozzle sizes for one board, you’ll have to change nozzles midway through. If you want to load 2 nozzles of the same size, you can do that too. There are several of each size.
It’s certainly easier to use full reels with leader tape preattached, but you can use cut tape too like you get when you order just 50 of something from Mouser. You just have to attach a leader tape and discard/reuse the first 40mm of parts. For parts that don’t come in reels or otherwise can’t go in one of the reel feeders, it has a row of trays up front where you can place parts for it to pick up.
You can either program it by hand using the front panel controls or you can give it a .csv file on an SD card. The file format is documented in the user manual and you can get an example file by inserting an SD card and having it create a new file. The program file consists of some configuration (offsets, speed, reel configuration) and a list of part placement lines. Each part placement line specifies which feeder to pick from and the x,y coordinates to place at.
Board alignment (as well as aforementioned manual programming) is aided by a crosshair laser mounted to the pickup head. The firmware unfortunately doesn’t make the best use of this, but you can use this to zero in on the center of a footprint for manual programming or (not conveniently, but possibly) a fiducial for board alignment.
Believe it or not, the only thing a pick and place machine does that a human can’t do is to work much faster. People do place these parts by hand every day. It may not be fun or fast or efficient if you have a lot to make, but a pick and place machine is absolutely not a requirement to make surface mount boards. It just makes it more efficient for high volume and it keeps us from having to do this monotonous task ourselves.
