Fixed vs. Removable Feeders on Benchtop PnP Machines - Page 1
Forum section: electronics / general

author: NF6X
author_rank: Unknown
timestamp: September 23, 2016, 06:55:38 pm
content: I've been studying the <$10k (US) pick and place machines available on Aliexpress. My application for one would be prototyping and small, intermittent runs, not daily production. I'm only looking at machines with vision systems at the moment.The least expensive machines have fixed feeder systems, typically hanging off one or more sides of the machine. There are also fancier machines with either pneumatic or electronic removable feeders. It seems to me that the fixed feeder systems can often handle more reels than the removable feeder systems. I presume that the removable feeder machines are probably faster since the feeders can advance each reel without needing the placement head to pull tape. I suspect that the removable feeder machines would allow faster reloading of a single reel if a spare feeder is available, and faster reconfiguration for different jobs if a whole batch of extra feeders is available.I don't know whether the advantages of removable feeders would be worth the extra cost for my applications, though. What do y'all think about fixed vs. removable feeder systems on these machines?

author: harry4516
author_rank: Regular Contributor
timestamp: September 23, 2016, 08:23:45 pm
content: not an easy question, Mark.I have a fixed feeder machine.In the beginning changing a reel was a nightmare,but now as I have changed a lot of reels its quite easy to do, I can change a reel in a minute.However, it's hard to draw the tape and cover-tape through all the rods and belts, easy to get knots in your fingers.If you want to spend the money, choose a removeable feeder machine.But please take care, feeders are not the only important thing in the PnP machine,placement accuracy, PCB mounting, custom trays and last but not least software quality are important issues.As you can see in the various threads here, <10k$ machines are far from being perfect, but still save a lot of time.

author: NF6X
author_rank: Unknown
timestamp: September 23, 2016, 08:41:55 pm
content: I am curious about how the cover tape take-up spooling works on the fixed feeder systems. What is involved in changing a single reel without disturbing the others? It looks to me like a new reel will just drop in, but how do you get the old cover tape out of the take-up spool? In the pictures of these units, it does not appear to me that individual take-up spools come out without major disassembly.The PnP machines that have most caught my eye so far are both Charmhigh machines: the CHMT48VB as a fixed feeder system, and the CHMT530P as a pneumatic feeder system.The CHMT48VB has 58 feeders, mounted on the left and right sides. Other systems with some feeders on the back look like they would take up a lot more floor space to provide access all around the machine.The CHMT530P only supports up to 30 feeders (fewer when using feeders for tapes over 8mm, of course), but they all load from the front. It looks like I could fit a CHMT530P, a solder stencil screen printer, and a small reflow oven all on a 6' x 3' bench with only the front edge needing to be easily accessible.

author: harry4516
author_rank: Regular Contributor
timestamp: September 23, 2016, 09:03:53 pm
content: check your circuit diagrams, I bet most of them will have more then 30 different parts.My machine (TVM802B which is mechanically almost identical to the CHMT48VB) has 46 feedersand I need additional custom trays for almost every board.I'll make a video during the weekend showing how to change a reel.

author: NF6X
author_rank: Unknown
timestamp: September 23, 2016, 09:05:54 pm
content: Good point. So, I'd probably be better off devoting a whole bench to a 58 feeder unit.Thanks for offering to make a video. I'm looking forward to seeing it.

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: September 23, 2016, 09:28:18 pm
content: Quote from: harry4516 on September 23, 2016, 09:03:53 pmBut this will tend reduce as you start designing more with production in mind. These days I rarely have more than 4 resistor values and 4 cap values in a design.Something to consider is that if you do have the occasional job with a large BOM, with (easily) removable feeders you can potentially place it in two passes, swapping feeders inbetween. Though the chances of Chinese software supporting this nicely are remote.

author: NF6X
author_rank: Unknown
timestamp: September 23, 2016, 09:30:07 pm
content: I'm still striving for a design with the perfect BOM: Nothing but 10k ohm 5% resistors!

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: September 23, 2016, 10:19:05 pm
content: Quote from: NF6X on September 23, 2016, 09:30:07 pm.. of course once you get to real production you realise that the cost of placing a part can be many times the cost of the part itself. You can get a lot of different values from a 10kx4 resistor network,

author: Kjelt
author_rank: Super Contributor
timestamp: September 23, 2016, 10:24:32 pm
content: Quote from: mikeselectricstuff on September 23, 2016, 09:28:18 pmJust create two projects run the first one on all pcbs for that day job then load the second project, change feeders and run the second job on all pcbs. Does not matter if it is chinese should work.

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: September 23, 2016, 10:28:27 pm
content: Quote from: Kjelt on September 23, 2016, 10:24:32 pmYes of course, but that assumes that swapping jobs is as quick and convenient as it ought to be... And you need to manually create the 2 job files and keep track of which parts are in which job.A well designed system would have a way to keep track of feeders and prompt the user to change as necessary.

author: Kjelt
author_rank: Super Contributor
timestamp: September 23, 2016, 10:34:33 pm
content: Indeed larger setups also often split one job in multiple parts but then sequentially for multiple p&p machines, one after the other, and the result is even a gain in throughput time compared to a single machine because they do not need to change nozzles, the larger parts are done by a seperate machine.But you already know that.

author: NF6X
author_rank: Unknown
timestamp: September 23, 2016, 10:51:11 pm
content: But I didn't already know that. Thanks!

author: thommo
author_rank: Frequent Contributor
timestamp: September 24, 2016, 04:05:36 am
content: NF6X,Worth you considering the TVM920 from QiHe also. Same manufacturer as Harry's machine actually, but totally different design.There is a blog subject for it on this forum. I have just purchased one, and I am aware that a string of other have also, or at least placed orders. They are a good company to deal with also.https://www.eevblog.com/forum/manufacture/pick-place-machinetvm920/

author: NF6X
author_rank: Unknown
timestamp: September 24, 2016, 04:14:32 am
content: I've read about the TVM920. It's a much bigger machine. Ideally, I'd like to cram a whole system of solder screen printer, pick-and-place machine, and small reflow oven on a single 6' x 3' bench, backed against a wall and obstructed on both ends. I don't think a TVM920 fits in that envelope.

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: September 24, 2016, 08:52:12 am
content: If it's not used that often you can probably save some space - e.g. store the printer under the P&P and bring out & put on another table when needed.

author: harry4516
author_rank: Regular Contributor
timestamp: September 24, 2016, 09:00:06 am
content: running two jobs on the same PCB sounds good, but is not feasible in practice with our small machines.As mikeselectricstuff posted, combining resistors to get a new value is what I am doing too, that helps a lot.I have equipped one row of feeders (the back feeders) with all the standard values 1k, 10k, 100k, 10n, 100n ...and try to use them as often as possible.The more specific values are in the other stack of feeders which are accessible more easily.There are still some parts left. Usually I use a custom stack, but what I also do: place it manually before soldering.You will need a microscope in any case. The placement quality of these small machines requires corrections from time to time before soldering.At that time I also place some parts manually, i.e. connectors, big parts like power inductors, and also parts which are not available in the machine.This takes only seconds and I think for prototyping this is acceptable.Harry

author: ar__systems
author_rank: Frequent Contributor
timestamp: September 24, 2016, 01:54:40 pm
content: Quote from: mikeselectricstuff on September 23, 2016, 09:28:18 pm4 resistors values is ridiculous. Maybe if you design purely digital circuits you can get away with 4 resistors. For any real circuit that is insufficient.We started doing double pass to save time. We place everything small (1206 and smaller) in one pass with two (same) small nozzles, and then second pass with two bigger (different) nozzles. To minimize changeover we we run 1st pass on 10+ boards panels, then 2nd pass.We are probably the most active users of TVM802B, hehe )) At this time we place at least 5000 components every week. The last batch is 500 boards, 38 machine placed parts per. Go at about 100 per day. On top of that we make 300 boards (~10 parts) every single week.

author: ar__systems
author_rank: Frequent Contributor
timestamp: September 24, 2016, 04:06:17 pm
content: The speed actually becomes important now. If I could load-and-go then I guess I could accept a slower speed, but this machine requires pretty constant supervision. Waste tapes routinely get tangled or stuck, and this causing feeder malfunction. If it runs slow and needs a guy to look at it pretty much non-stop, then it becomes expensive.

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: September 24, 2016, 06:38:26 pm
content: From what I've seen so far, Chinese manufacturers haven't understood the impirtance of being able to just let the machine get on with the job with minimal attention. Possibly a side effect of most of their market being local, where labour is cheap.An example,from Neoden,but I suspect common, is the stupid handling of errors, where they just stop and demand attention instead of carrying on with the next feeder and doing all it can, so it only needs attantion once to clear all issues at once.

author: NF6X
author_rank: Unknown
timestamp: September 24, 2016, 06:49:40 pm
content: Has anybody looked into starting with one of the <$10k Chinese machines, then replacing the software with something like OpenPnP to allow things like error handling to be improved?

author: NF6X
author_rank: Unknown
timestamp: September 24, 2016, 06:54:22 pm
content: Quote from: harry4516 on September 24, 2016, 09:00:06 amI have an Amscope binocular microscope that I use for hand assembly. The spot in my house that I'm considering for the automated bench is distant from my main workbench, but I could mount another microscope arm at the automated bench and move the microscope head back and forth. Or I could just get a second microscope if that proves to be too cumbersome.Are the machines with vision systems still prone to making boards that need corrections, or is that just an issue on the less expensive open-loop machines?

author: ar__systems
author_rank: Frequent Contributor
timestamp: September 24, 2016, 07:07:41 pm
content: Open or closed loop has nothing to do with this. Mechanics of the machine is good enough. If you stick with 0603 and larger parts, and chips with at least 0.050" pitch you can get away with nearly perfect assembly time and time again. Anything smaller and placement is less than perfect due to crappy visual subsystem. It just does not work consistently.We have reversed protocol of the TVM802 pretty much entirely, but so far I have not heard about OpenPNP integration. I still have plans to reimplement the stock s/w, but seing that I'm constantly busy with other projects, looks like it is not going to happen until I hire someone to do thatI think that's what I will have to do next month.

author: NF6X
author_rank: Unknown
timestamp: September 24, 2016, 07:17:52 pm
content: I see. I'm interested in assembling boards using 0402 discrete components, 0.5mm pitch QFP up to 144 pins, SC70 sized small devices, and so forth. Would any of these small machines be up to the task?

author: ar__systems
author_rank: Frequent Contributor
timestamp: September 24, 2016, 07:43:32 pm
content: We placed many 0.5mm pitch parts. They require manual checking and correction all the time. Did not try 0402.

author: harry4516
author_rank: Regular Contributor
timestamp: September 24, 2016, 09:48:39 pm
content: Quote from: ar__systems on September 24, 2016, 07:43:32 pm100% ACK, same here.Correcting parts, placing a few parts manually, soldering and pasting a new board requires almost the same time as the machine needs for PnP.The workflow is ok, no waste of time. Currently I do about 6 to 8 boards per hour, up to 50 boards per day is no problem, except that I get tired after a few hours which is the main limitation for quantity. But to be honest, if I need 100+ boards I go to an external company since PnP isn't the only issue.Perfect soldering and low humidity storage of parts is not so easy to do in a prototyping environment.By the way, if you plan to buy one of these Chinese paste printers, be aware that they are designed for framed stencils and these frames are very unusual in Europe and maybe in US. I have one of these printers and never used it because of this special frames.

author: ar__systems
author_rank: Frequent Contributor
timestamp: September 24, 2016, 09:59:31 pm
content: Quote from: harry4516 link=topic=74681.msg1034306#msg1034306Currently I do about 6 to 8 boards per hour, up to 50 boards per day is no problem,[/quote

author: IconicPCB
author_rank: Super Contributor
timestamp: September 25, 2016, 02:38:30 am
content: We run a small Mechatronika M10V.No problems in placing 0402 components.In M10V is certified to place 0201 to 40mmx40mm up to 0.5mm pitch components.Placement rate 1400 to 1600 chips per hour

author: thommo
author_rank: Frequent Contributor
timestamp: September 25, 2016, 03:16:38 am
content: Hi IconicPCB,I got some questions for you if you wouldn't mind taking the time.Does your Mechatronika M10V use electric or pneumatic power for its feeders?And are they Mechatronic proprietary, or industry standard Yamaha, or similar?Did you purchase it through a local distributor, or directly from the guys in Poland?How long have you been running this machine now?Thanks - PQuote from: IconicPCB on September 25, 2016, 02:38:30 am

author: NF6X
author_rank: Unknown
timestamp: September 25, 2016, 03:22:47 am
content: I am also curious about the M10V. About how much do they cost? I didn't see any US distributors listed on their site, and it only listed 220V 50 Hz power input, so I wonder if it is practical for US buyers.

author: ar__systems
author_rank: Frequent Contributor
timestamp: September 25, 2016, 03:38:32 am
content: 220 is not a problem. Your drier and stove are 220V.

author: NF6X
author_rank: Unknown
timestamp: September 25, 2016, 03:42:18 am
content: Oh, I know. I just don't want to crawl under the house to run a conduit to the place in my breakfast nook where I would like to set up an SMT line.

author: IconicPCB
author_rank: Super Contributor
timestamp: September 25, 2016, 03:53:34 am
content: G'day Thommo,Feeders are a bit awkward as they come in predetermined feeder blocks.You get to chose which block combos you wish and thats the choice to live with.I did a bit of investigation into typical product component mix and based on that selected the feeders i thought would be the most general in their application.So far so good.Ability to use trays , bins and cut tape feeders which are all freely configurable ( during program preparation ) is a real boon.The machine may carry up to a hundred plus different components on cut tape feeders.Feeders are electrical feeders with programmable component pitch ( 2,4, ... etc holes ).We purchased the machine directly from the factory.There are some second hand units available in Europe ( these are earlier mechanical pincer like component centering ). Nice thing about M10V is dual vision system. Fiducial and component recognition.Vision systems is based on a couple of cameras and Picollo PCI vision card.We have had the machine a couple of years. We use frame less stencils which we cut ourselves for 0603 and larger components otherwise we go with 0.1mm stanless stencils from china.I am in the process of building up a laser cutter for stainless stencils so we can respond to client needs more comprehensively.The soldering is done in an APS GF-12 reflow oven, a small four zone conveyorised machine capable of processing lead free paste.HF6X,I am sorry can not tell You how much they are now. Being an European product be prepared for prices whihc are a bit stronger than Chinese.A bank of feeders will cost You approximately 3KEuro.Machine frame will cost You in the ten plus K Euro.Do not worry about 220V 50Hz requirement. It is only a small inconvenience of a step up transformer.And note any gear operating on 50Hz wil have transformers whihc are more than capable of operating at 60Hz whereas 60Hz gear may have issues with 50Hz power.

author: NF6X
author_rank: Unknown
timestamp: September 25, 2016, 04:13:32 am
content: I wouldn't even need a transformer since 220V is available in US residences; it just isn't routed to normal convenience outlets here. I would just need to verify that the machine can handle 60 Hz power, which is more likely than the other way around.I'm not sure that the M10V would be the most practical choice for me, but the loose component capability does sound pretty cool.

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: September 25, 2016, 08:24:20 am
content: Quote from: IconicPCB on September 25, 2016, 03:53:34 amWhy type/spec of laser ?

author: harry4516
author_rank: Regular Contributor
timestamp: September 25, 2016, 05:21:28 pm
content: as promised, here is the video showing how to change a reel in a fixed feeder machine.First a normal run, followed by a detailed description.https://youtu.be/mYsZXfXaNlYQuote from: NF6X on September 25, 2016, 04:13:32 amdepends on your budget, the MV10 is >>>>>10k

author: NF6X
author_rank: Unknown
timestamp: September 25, 2016, 05:47:35 pm
content: Thank you for making the video. It was very helpful.So, to removed cover tape from a take-up spool, do you just grab the loose and and pull to unspool the whole length?

author: harry4516
author_rank: Regular Contributor
timestamp: September 25, 2016, 09:22:23 pm
content: Quote from: NF6X on September 25, 2016, 05:47:35 pmyes, thats what I do, takes only seconds.

author: Kjelt
author_rank: Super Contributor
timestamp: September 25, 2016, 09:35:34 pm
content: Quote from: harry4516 on September 25, 2016, 05:21:28 pmThanks for the video, not very practical to change lets say 10 spools for a second run this way.

author: Smallsmt
author_rank: Frequent Contributor
timestamp: September 25, 2016, 10:48:33 pm
content: It really depends on the grade of automation you want to reach.For a simple prototyper every cheap machine including reels and spools can meets your needs. Drag feeder and spools are ok for simple prototyping.If you increase the part count for a single placement job you need a high feeder count machine and thats expensive if it has cassettes.The reliability is even better if you have push feeders so the head don't need to drag the tape.For smaller parts it should be possible to adjust the peel off process in movement and speed because some parts jump out of the pockets if cover tape is always removed in the same speed. The precision must be much better for small parts.And finally the next step if you want more flexibility for machine setup the cassette machines where your choice because of easy part change.Machine price and reliability increases again. You can operate your machine without the need to supervisor it.The last step you find in the professional grade machines they use intelligent feeder systems to detect any kind of problem inside the feeder cassette and maybe switch over to a spare cassette. The stock count will be monitored too.So this is the comfortable solution if money takes no care and you want to run a proffessional production.Any customer is different and they scale their needs on money and time to make a good decision.Best regardsMichael

author: harry4516
author_rank: Regular Contributor
timestamp: September 26, 2016, 08:40:08 pm
content: yes, we are always looking for the best compromize between feeders, precision and cost.That's what I like with your VP2800. 90 feeders sounds good.How do you handle custom trays or short loose tapes, is it possible to enter custom pick-up coordinates ?

author: Smallsmt
author_rank: Frequent Contributor
timestamp: September 27, 2016, 02:57:41 pm
content: Quote from: harry4516 on September 26, 2016, 08:40:08 pmWe use software defined feeder to define single pick up points , rows (strips), columns (strips) or arrays (trays) by starting cooordinate, distance X, Y and row / column count.There are no limits for the feeder count only area restrictions.A software feeder need to keep the working area and the maximum Z axis height.Best RegardsMichael

author: IconicPCB
author_rank: Super Contributor
timestamp: September 27, 2016, 09:17:04 pm
content: Mike,It is a pulsed ytterbium fiber laser 1060 to 1085 nm wavelengthsingle pulse energy 1mJ @30KHzpulse repetition rate up to 60KHznotionally 30W unitYes it does not seem like a laser source providing enough ergs to cut through steel but it is only 0.1mm or thereabouts I wish to process.I have seen a video of a 50W unit handling 3mm thick stainless steel plate so I reckon 30W is more than enough.These units are used in etching up to a depth of 0.5mm