Very low cost Pick and Place kit - Page 1
Forum section: electronics / general

author: ottoragam
author_rank: Contributor
timestamp: August 21, 2019, 08:57:20 pm
content: Howdy people,I recently built a pick and place machine to help me with some low volume assembly jobs. I wanted something simple and low cost, but reliable and expandable. The machine worked very well, I was able to do in a few hours what would've taken me 2 days to do by hand. So I thought more people might benefit from such machine, and I'm planning to offer a kit starting at about $500 USD for the base configuration.The head uses a hollow shaft stepper to allow a DC suction pump to suck the components. The DC pump could be an optional accessory, to allow the final user to use something else to provide vacuum in the case less noise or different performance is needed.This assembly also has a down looking HD camera with an interchangeable lens that can be manually focused, with a similar optional up looking unit.The nozzle travel is 35 mm and it uses Samsung CP45 units, with an automatic nozzle changer option.The kit will include the custom CNC milled and turned parts, Al extrusions, and linear motion components.Work area is between 350 and 400 mm in X and Y (could be bigger), and the linear motion is achieved using linear rails, timing belts and stepper motors. Everything is controlled by a pair of GRBL boards (I need to design a custom head mounted control board, and a base motherboard to plug everything in nicely), and OpenPnP provides the brains for the operation. At this moment, the machine manages around 750 components per hour using computer vision and it handles 0402s just fine (I've not tested 0201s yet).Gino

author: spanner888
author_rank: Contributor
timestamp: August 22, 2019, 01:02:45 am
content: OK, interesting, but please clarify some details.1. Are you selling the modules assembled as per photos?2. Lost cost = great and from your comments, you have not yet finalised all the parts, but give us a ballpark idea at least!3. Gotta link us to a video of pnp in action and some close up photos of finished PCBs

author: KE5FX
author_rank: Super Contributor
timestamp: August 22, 2019, 01:09:12 am
content: Sounds interesting! Definitely would be good to see a video.

author: ebclr
author_rank: Super Contributor
timestamp: August 22, 2019, 05:02:58 am
content: What about the software, to drive those things?

author: ottoragam
author_rank: Contributor
timestamp: August 22, 2019, 04:20:15 pm
content: Quote from: spanner888 on August 22, 2019, 01:02:45 amYeah, the idea is to sell a kit containing the prefabricated mechanical en electrical modules, so it's easy to ship and assemble by the final user.I believe the cost will be around $500 USD. I plan to offer tape trays, an automatic nozzle changer, and some other items as optional extras too, but the base model will be capable of running complete assembly jobs.Here's a little video I made of the first test. Keep in mind that I was connecting and disconnecting the pump by hand, so it's a bit sloppy. I'm designing a PCB that will serve as a calibration job. I'll post more info as the project progresses

author: ottoragam
author_rank: Contributor
timestamp: August 22, 2019, 04:24:03 pm
content: Quote from: ebclr on August 22, 2019, 05:02:58 amSee the comment above, it is a video of my first test. I'll post a complete assembly job in a few days.

author: ottoragam
author_rank: Contributor
timestamp: August 22, 2019, 04:26:28 pm
content: Quote from: ebclr on August 22, 2019, 05:02:58 amThe machine uses OpenPnP to prepare and run the jobs. It works really well, and I'll be providing a configuration file, manual and tutorials for using the software.

author: ottoragam
author_rank: Contributor
timestamp: August 22, 2019, 06:12:54 pm
content: Here's the assembled machine:

author: electrode
author_rank: Regular Contributor
timestamp: August 22, 2019, 09:36:44 pm
content: This is pretty cool. I notice the nozzle is (softly?) sprung – does this make (auto)levelling quite easy? Can you just tell it the board thickness and the tape thickness and let it rip?

author: ottoragam
author_rank: Contributor
timestamp: August 22, 2019, 09:57:06 pm
content: Quote from: electrode on August 22, 2019, 09:36:44 pmYes, the nozzle tips can be compressed to allow for some Z error. And indeed, you need to tell the software the Z position of the surface of the PCB and where the component tapes are mounted, and the thickness of each unique component. OpenPnp handles the rest.When I shot the video I was using off the shelf Juki 500 series nozzles, and I recently got some Samsung CP45 nozzles because I want to take advantage of its tapered body to design a very simple automatic nozzle changing station.

author: langwadt
author_rank: Super Contributor
timestamp: August 22, 2019, 10:16:51 pm
content: Quote from: ottoragam on August 22, 2019, 06:12:54 pmI think it could be reduced even more, the mgn rail is probably straighter and stronger than the 20x20mm alu extrusion so I don't much need for that on the X-axisif using two different size of rails the hole pattern on the smaller rail fits the hole pattern on the bigger carriagethis pic mgn15 and mgn12, but the same goes for mgn12 and mgn9and if you stand the x-axis stepper like the y-axis the x/y-axis can be flat plate

author: Kjelt
author_rank: Super Contributor
timestamp: August 22, 2019, 10:25:22 pm
content: Quote from: langwadt on August 22, 2019, 10:16:51 pmBut Inthink you need the height for the z axis and components ?

author: langwadt
author_rank: Super Contributor
timestamp: August 22, 2019, 10:28:00 pm
content: Quote from: Kjelt on August 22, 2019, 10:25:22 pmit doesn't change the height of the x-axis

author: ottoragam
author_rank: Contributor
timestamp: August 22, 2019, 10:55:42 pm
content: Quote from: langwadt on August 22, 2019, 10:16:51 pmI'm using the 2020 extrusion to allow attaching stuff easily to the machine frame, like feeders, fixtures, a table... It's more of a feature for the final user, makes expanding the machine easier. Also, the 2020 modules are easier to ship than a base plate.

author: langwadt
author_rank: Super Contributor
timestamp: August 22, 2019, 10:59:39 pm
content: Quote from: ottoragam on August 22, 2019, 10:55:42 pmsure you need the square frame, I was talking just the x-axis

author: ottoragam
author_rank: Contributor
timestamp: August 22, 2019, 11:15:00 pm
content: Quote from: langwadt on August 22, 2019, 10:59:39 pmGotcha, that could be an option too. Also saves a little weight.

author: SWR
author_rank: Regular Contributor
timestamp: August 23, 2019, 10:28:28 pm
content: Quote from: langwadt on August 22, 2019, 10:59:39 pmIf you want to make stuff dirt cheap you've got to remove as many components as possible and make the remaining components as cheap (often=flimsy) as possible.A few options:- Scrap the frame and bolt the MGN9 rails to a cheap & easy to clean laminated kitchen shelf.- To get away with the flimsiest dimensions possible yo need to reduce the moving weight.- Only drive first axis on one side and let it follow freely on the far side.- Put 3 stepper motors on the outside of the near side so the moment of inertia balances out with the cross rail.- This will be affected by the position of the head on the cross rail, so keep it light and balance the center position.- On the far side you only have light weight rollers to return the thin 6mm tooth belts.- One belt will drive the head position on the cross rail (belt in any orientation).- Another belt will drive the vertical position of the two pic & place heads (belt horizontal).- When one head goes up the other goes down.- This belt will have to move synchronously with the head position belt to keep the vertical position stationary.- The third belt controls the rotation of both heads (belt vertical).- This belt will also have to move synchronously with the head position belt to keep the rotation stationary.- All electronic and vaccuum control should be placed with the motors so the only connection is power and vaccuum.- Maybe a couple of DC supply wires could be placed inside the vaccuum connection tube to reduce the clutter?- Find the mechanical resonance frequency of the assembled cross rail (this will vary with head position on the cross rail).- Accelerate and decelerate the cross rail on a cosine curve with the frequency matching the resonance frequency at a given head position.- This will prevent vibration when the cross rail has reached its end position (just like you do when controlling a gun turret to fire quickly).- You essentially replace structural rigidity with more complex acceleration and deceleration equations (but math is cheap these days).The only mass attached to the head should be a linear bearing, belts, belt fittings, the suction heads, vaccuum tubes and a very light camera.Disclaimer: These are just penny pinching ideas - I have no practical experience with this specific application.

author: ottoragam
author_rank: Contributor
timestamp: August 24, 2019, 07:38:19 pm
content: The current machine structure is for sure not the definitive and final product. Thanks for the ideas, SWR, I still need to further optimize the design, so I appreciate the feedback very much.

author: ottoragam
author_rank: Contributor
timestamp: August 24, 2019, 07:43:45 pm
content: I wanted to make a video to showcase the general operation of the SimplePnP. The machine is sorting a few scrabble letters using my new Samsung CP45 nozzle holder, without computer vision assistance. Here I'm using a dial vacuum gauge to make sure suction is achieved. Normally, a pressure transducer is used instead, to provide feedback on whether the component was picked correctly or not.

author: fki82
author_rank: Contributor
timestamp: August 29, 2019, 09:32:06 pm
content: Cool idear!I’m currently building a OpenPNP based machine myself. But mine has a lot more parts…I’m looking forward to seeing with how little and simple parts you can get away and it still works.Are you planning on having bottom vision?

author: mrpackethead
author_rank: Super Contributor
timestamp: August 29, 2019, 10:36:46 pm
content: These kind of machines are awsome learning and experimental things. And they are great for that. And as long as you understand that, and dont' try to build a business around using these machines to deliver products/services all is great.

author: Kjelt
author_rank: Super Contributor
timestamp: August 30, 2019, 08:08:07 am
content: Meah if you are a startup and sell up to 50 boards a month and your self built openpnp machine places the components correctly , why not? You can earn the money for a better quicker machine if needed.If something breaks down you can repair it your self since you built the machine.Go try that at your professional factory where a team has to be flown in from hundreds of kms away to repair your machine. And where you so heaviliy depend upon that quality that this hours of non productivity costs you a lot of money.Besides me personally am completely fed up with the capatalist pressure to keep on expanding your business till you have tens of machines and tens of personell, and you are only doing the payslip signing and talking to the customers and your staff is doing the fun things.There is nothing wrong with a small scale one or two person run business, have fun , this is your life, live it now and enjoy instead of waiting till retirement.

author: Fire Doger
author_rank: Regular Contributor
timestamp: August 30, 2019, 09:43:10 am
content: Quote from: Kjelt on August 30, 2019, 08:08:07 amIn other words, hand assembly to full equipped 5digit PnP is a big gap and has it's market. PnP owners are a bit fanboys some times...From my research the most expensive part was the header, cameras and step controllers. If you have a mill you can make a very nice machine, slow, but accurate...

author: ottoragam
author_rank: Contributor
timestamp: August 30, 2019, 05:10:15 pm
content: Quote from: fki82 on August 29, 2019, 09:32:06 pmYes, I use the same camera model for bottom vision, just with a shorter focal distance. I still need to do some work on an illuminated enclosure for it tho.

author: ottoragam
author_rank: Contributor
timestamp: August 30, 2019, 05:29:01 pm
content: Quote from: Kjelt on August 30, 2019, 08:08:07 amSpot on.

author: mrpackethead
author_rank: Super Contributor
timestamp: August 30, 2019, 09:23:37 pm
content: Quote from: Kjelt on August 30, 2019, 08:08:07 amHaving good machinery, that does the job efficently and quickly, has meant i've not had to have tens of stuff, you just need a couple of people putting stuff in, and taking it out. When it breaks you can fix high end machines as well yourself. I guess we are all on a continium of experience. I started out with a home built PNP... and well, hard expereince, i have old but good commerical machines now, and it was absolutely the right decision for me.QuoteIf you want to spend your time feeding and watering PNP machines then cool. I want to spend my time to doing fun things.. Building boards is not a fun thing. Its thing that means i can do fun thngs

author: ottoragam
author_rank: Contributor
timestamp: August 30, 2019, 10:12:46 pm
content: I'm pretty sure you understand the advantage that having several tiers of the same product provides. These kind of machines are not meant to be used to handle big and complex assembly jobs, but there are many business opportunities where electronics assembly is required where a machine like this is all that's needed or can be justified. And many times outsourcing PCBA is not a good choice either.I also don't find building boards too thrilling, that's why this PnP came to life.

author: mrpackethead
author_rank: Super Contributor
timestamp: August 31, 2019, 01:14:32 am
content: Quote from: ottoragam on August 30, 2019, 10:12:46 pmYes, i understnad differnet teirs. I dont' have a line that can place 200kpph, likei Samsung does in Malaysia. I have a line that can do about 12kpph ( real numbers ) But I've done also done micro pnp , in several guises much like your machine. I would argue that there may well be a negetive efficency with 'entry level pnp'. It will cost more to use than well organised manual placement. For some jobs / situations that may be acceptable. For someone making 50 boards per month, maybe not. But there is a LOT of good in building and learning to use one of these. You'll learn a lot. and any learning is awesome.

author: ottoragam
author_rank: Contributor
timestamp: August 31, 2019, 02:38:08 am
content: Quote from: mrpackethead on August 31, 2019, 01:14:32 amI understand that. I was worried about that too when I started considering building the PnP. So far I don't regret it at all. I spent about $800 USD (less if you count only what ended up in the final iteration) for the stuff I used to get the machine through various design changes. Manual stations cost several hundred dollars too, so the cost difference isn't very significant. However, I don't need to do the actual component installation myself, which is a huge advantage due to the tedium of the repetitive task, and my back doesn't get tired due to being hunched over the board.Maybe I need to babysit the machine a little, but that's also true for other CNC equipment. Configuring the assembly jobs and loading the cut tape feeders is way better that the other part of this ordeal.

author: Kjelt
author_rank: Super Contributor
timestamp: August 31, 2019, 08:12:18 am
content: Quote from: mrpackethead on August 30, 2019, 09:23:37 pmAnd that is the difference you look at it as a tool, the starters look at it as a cool project to learn.And upto a certain amount of boards this is really feasable IMO.Above a certain amount and you don't like it, let the pro's handle it esp with extreme large quantities.But using old 2nd hand gear can get you sometime when spare parts become unobtanium or rediculously overpriced since someone thinks he has gold.Yesterday I tore down an Assembleon AX2.. machine, I got the TH pick and place head partly. Looked online they ask $8k for a NOSI also got the bottom camera unit with a Marlin firewire camera. NOS $900.-Looking at the industrial PC with two processorcards and six! Other cards booting probably Win NT3.x , the firewire cameras and DC brush servos, control card running on an 8044 with LM628 motioncontroller, makes me realize that if something breaks down you are in deep sh*t. Good luck getting the service manuals etc.But hey if it works for you great, put it in a topic where it matters, but not in the VERY LOW COST P&P topic, you are barking up the wrong tree

author: mrpackethead
author_rank: Super Contributor
timestamp: August 31, 2019, 09:14:28 pm
content: Quote from: Kjelt on August 31, 2019, 08:12:18 amNo, i'm looking at this has a 'learning' project as well. I wrote this several posts ago.QuoteThere are some use-cases that this class of machine will cater for. The problem that seems to occur is that some peoples expectations, dont' match the reality of the limitations....

author: NorthGuy
author_rank: Super Contributor
timestamp: September 04, 2019, 07:59:15 pm
content: Quote from: Kjelt on August 30, 2019, 08:08:07 amYou certainly can, but automated PnP head is not exactly the whole machine. You will also need feeders, otherwise your PnP head is mostly useless. Feeders are far more complex. This is not something you can build easily or cheaply.

author: SWR
author_rank: Regular Contributor
timestamp: September 04, 2019, 10:43:32 pm
content: Quote from: NorthGuy on September 04, 2019, 07:59:15 pmAnother more low cost option is to go with fixed feeders. I know it's not acceptable to an EMS with many different customers and PCB designs due to the longer setup time, but if you're only doing a few differen't boards of your own design, then it might be a viable option.I've got a small desktop P&P with 79 reels, 22 cut tape and 7 sticks plus trays. I can cover my different designs by choosing as many possible from my common components on the reels and then placing special parts on cut tape, sticks or trays.If I need higher quantities of a non-common component I have to mount a reel which takes longer than swapping a feeder, but it also takes time to mount the reels in a feeder although it's less than the fixed reels.The big downside of feeders is the initial cost. Buying 100 or 200 feeders would cost more than I paid for the machine including the 79 fixed reel feeders. It's one of those tradeoffs you might be willing to take if you prioritize low purchase cost over time saving.I think it's time well spent to do a bit of analysis on your current and near future needs regarding component diversity and needed flexibility before choosing a machine. I was in the lucky situation that I had a list of projects I want to do during the next 3-4 years that was fairly easy to assess on the hardware side. Most of my complexity will be in the software development.

author: ottoragam
author_rank: Contributor
timestamp: September 07, 2019, 09:37:38 pm
content: Quote from: SWR on September 04, 2019, 10:43:32 pmAgreed. There are also low cost 3D printable feeder designs available on the web (like this onehttps://docs.mgrl.de/maschine:pickandplace:feeder:0816feeder). So if you have a bit of time, you can print yourself some feeders to accommodate for a larger component library.

author: Harjit
author_rank: Regular Contributor
timestamp: September 10, 2019, 10:56:06 pm
content: Love the simplicity!I've started down this road and had some questions for you - where did you end up getting the "plates" that you use to connect the y axis rails to the X axis rail, the X axis motor bracket, etc.?How are you attaching the belt attach point to the plates?Are you getting your Samsung nozzles and holder off of AliExpress or elsewhere? How is the quality? I need to order some, which is why I'm asking.So, far, I've got the Al extrusions, the rails, steppers, pulleys, power supply.

author: ottoragam
author_rank: Contributor
timestamp: September 11, 2019, 03:08:25 pm
content: Quote from: Harjit on September 10, 2019, 10:56:06 pmI milled the extrusion, motor, pulley and camera brackets. The head plate and nozzle holder are also custom machined. The most critical part is the nozzle holder, as low run out will allow for better part placement accuracy.The belts are attached using a 3D printed clamp where I slide the teeth. I haven't published my design, but there are several available on the web if you wish to make your own, or you can buy some metal ones.The nozzles are from Robotdigg. I tested some Juki 5xx ones too, but I find the Samsung ones to be better made. Their spring loaded stroke is shorter, for what is worth.Let me know if you have more questions!

author: Harjit
author_rank: Regular Contributor
timestamp: September 12, 2019, 03:53:55 am
content: Thank you.I wonder / think the head design is ripe for innovation. The current designs use stepper motors with shafts that have holes. These steppers are way more powerful than they need to be. They are also heavy. This then makes the motor that pulls them up and down larger. Which makes the X-axis motor larger. Which makes the Y-axis motor larger.This thread has some discussion about an alternate:https://groups.google.com/forum/#!topic/openpnp/UexQ1whelYEI want to take the ideas at the above link a littler further and put a tiny vacuum pump either on the head or on the head carriage. This will eliminate the long tubes and reduce mass and drag.

author: Fire Doger
author_rank: Regular Contributor
timestamp: September 12, 2019, 08:46:03 am
content: Quote from: Harjit on September 12, 2019, 03:53:55 amToo much vibration or very low vacuum.

author: ottoragam
author_rank: Contributor
timestamp: September 12, 2019, 04:02:32 pm
content: Fire Doger is right. I prefer to have an air line connected to the head so I can use a silent vacuum source, and the small pumps cannot deal with a tiny leak, they don't provide enough flow and pressure.

author: Harjit
author_rank: Regular Contributor
timestamp: September 12, 2019, 04:27:26 pm
content: Valid concerns.FWIW, the vacuum pump I was thinking of using is the same / similar one to the one used in the Hakko 394. I have one and took it apart and got the part number from there.

author: SWR
author_rank: Regular Contributor
timestamp: September 12, 2019, 07:02:47 pm
content: Quote from: Harjit on September 12, 2019, 03:53:55 amA few ideas:How about a dual head built with 3 micro servos?They are cheap, light weight and low power.One servo on each head is used for component rotation.The best resolution I've found is 1024 steps on 180° equal to 0.2° resolution.Example: Tower Pro SG90 Digital 9g with 1us dead band (SG92R Digital has similar resolution).That is 0.065mm or 2.5mil steps on the corner of a 30x30mm component.This can be turned into 360° positioning by rotating the servo before pick-up and again before adjustment/placement.The nozzle adapter with vacuum tube attachment and servo spline connector can be 3D printed.The exact cone shape could be improved by turning a soldering iron tip with the exact conus shape,and heat it to the proper temperature before pressing into the 3D printed conus shape to smooth it out.The last servo is driving a small tooth belt with the heads attached to each side.When one head goes up the other goes down and both are level when the servo is centered.If you need 10mm vertical clearance on each head you need 20mm movement.That is 0.02mm or 0.8mil vertical resolution.With a small ESP32-CAM communicating via WiFi and driving the 3 servos and the camera, you only need 2 wire dc power.This would require good capacitive decoupling of the dc power due to current spikes drawn by the servos.

author: mrpackethead
author_rank: Super Contributor
timestamp: September 13, 2019, 07:11:15 am
content: Using some of the components that you can get as spares from some of the commerical machines is not a bad idea either. Theres a guy in Australia thats taken some assemblys of a Yamaha machine. Its also well worth considering using a venturi vacumn generator on the head ( very light ) and just supply compressed air. Ideall you want both positive and negetive pressure, as being able to 'blow' the compoennet of the nozzle is a really nice thing to have. They often just wont' drop' off. You also then have a really simple way of using off the shelf nozzles.

author: Kjelt
author_rank: Super Contributor
timestamp: September 13, 2019, 07:41:01 am
content: The main challenge is still the valves. On commercial machines you see very tiny very expensive swiss made valves and sometimes a custom aluminium milled block of valves.They have multiple pressures which can be achieved with a pressure regulator, one for the pneumatic head to operate usually in the order of 5 bars pressure and one for blowing of the component which is very low pressure order of 0,5 bar above the roompressure. Crucial is the timing by placing: drop head, release vacuum, apply blow of pressure, release blow off pressure, raise head.

author: SMTech
author_rank: Frequent Contributor
timestamp: September 13, 2019, 11:27:03 am
content: The valves in the head of our Essemtec are made by SMC and if you look up the part number are made specifically for surface mount machines. Not about to pull the cover off right now but from memory they are DIN rail mounted, no fancy milling and have pressure adjustment grommets on them. Most machines (including this one) use a venturi, it may even be a built into that SMC valve assembly, not about to take the hidden bits apart to find out. Notably Europlacer & Mycronic have built in vac generators, Mycronic needs no air supply at all IIRC and Europlacer uses a little, mostly for the feeder trolley clamps. In software you can define how long before the device is reached the vac turns on, how long it remains at rest before moving up, blow off durations are very short.The old Versatronics machine we used to run, has a pump in arm, it was more effective than you might think and the lack of blow off never really caused an issue, but then it wasn't even capable of picking or placing anything exotic. However blow-off is a fairly inaccurate name, for the most part its just about clearing residual vacuum, tiny little pumps probably leak enough for that not to matter.

author: SWR
author_rank: Regular Contributor
timestamp: September 13, 2019, 11:38:05 am
content: I absolutely agree that you need the blow off to get somewhat decent reliability.I saw these cheap mineature pumps on Aliexpress.The 6V version sould fit nicely with the servos for a single DC power supply.I don't know if:- 3,2 L/min per nozzle is enough to pick up the component reliably?- Do they have adequate lifetime?- Can you switch from suction to blow by reversing the motor polarity?- Can you monitor the vacuum (detect pick-up failures) by monitoring the motor current?When using dirt cheap components (these are $3 each) you have to do some testing to find the performance and lifetime limitations, so it's a some-assembly-required approach and it might end up being a dead end.

author: Kjelt
author_rank: Super Contributor
timestamp: September 13, 2019, 03:42:01 pm
content: Quote from: SMTech on September 13, 2019, 11:27:03 amI would appreciate it if next time the cover needs to come off you can take a picture of the type numberSounds like an obtainable item

author: NorthGuy
author_rank: Super Contributor
timestamp: September 13, 2019, 04:05:38 pm
content: Quote from: SWR on September 13, 2019, 11:38:05 amI placed quite a bit of components for prototyping manually, and I don't remember them sticking to the nozzle (well if you dip the nozzle into flux or paste, that's another story). How come this is such a problem with machines?

author: Harjit
author_rank: Regular Contributor
timestamp: September 13, 2019, 04:56:54 pm
content: Quote from: NorthGuy on September 13, 2019, 04:05:38 pmFrom what I've read, it isn't a problem. Apparently, when the component is placed, the surface tension of the paste pulls it off the nozzle.Pumps I found interesting:https://www.aliexpress.com/item/32863883713.html?spm=a2g0o.productlist.0.0.4d7d73cdfqFFcb&algo_pvid=c5abc8d4-f9e8-4e49-a8fa-f7eb2891df02&algo_expid=c5abc8d4-f9e8-4e49-a8fa-f7eb2891df02-4&btsid=ce5a9812-1180-4322-8446-af36515867df&ws_ab_test=searchweb0_0,searchweb201602_7,searchweb201603_52https://www.aliexpress.com/item/32857665192.html?spm=a2g0o.productlist.0.0.4d7d73cdfqFFcb&algo_pvid=c5abc8d4-f9e8-4e49-a8fa-f7eb2891df02&algo_expid=c5abc8d4-f9e8-4e49-a8fa-f7eb2891df02-11&btsid=ce5a9812-1180-4322-8446-af36515867df&ws_ab_test=searchweb0_0,searchweb201602_7,searchweb201603_52Don't know if they are adequate or not.

author: ottoragam
author_rank: Contributor
timestamp: September 14, 2019, 07:37:15 pm
content: They look underpowered to me. I tried the head mounted pump approach, but didn't like the results. I also think they're a bit expensive for what you're getting.

author: Fire Doger
author_rank: Regular Contributor
timestamp: September 15, 2019, 12:59:04 pm
content: Quote from: Harjit on September 13, 2019, 04:56:54 pmIf your loop has no leaks then surface tension is not enough to pull it. Especially if you use the black suction cup at the tip end.Its a constant balance between air leaking and vacuum.If your nozzle leaks (simple needle) or loop in general when you stop the pump pressure is equalized fast and surface tension does the job. -> Need more vacuumIf it doesn't leak when you stop the pump it will need more time for pressure to equalize. -> Less vacuum but you need more component in loop (valve)I believe having big vacuum is the best becauseA) You can PWM it or use valves to limit the airflowB) You can lift heavy parts by using nozzles with suction cup (high vacuum + low leak)C) You can have higher jerk without worrying about part shifting or fallingD) You can have a more controlled environment by having a vacuum chamber. Direct pump doesn't push - pull air constantly, its more like sawtooth and chamber acts like a cap.Making lighter head is very important if you use belts for driving the head because momentum couples directly on motor shaft.If you use trapezoid lead screw most of the momentum doesn't couple to shaft as a rotational vector (depends on screw pitch, smaller pitch = easier to rotate) so you don't need to care about weight and jerk.The negative is that you loose speed because pitch increased. The cost increases if you use better motors but I would prefer to buy an accurate slow machine than a fast machine that needs constant observation.

author: langwadt
author_rank: Super Contributor
timestamp: September 15, 2019, 01:34:52 pm
content: Quote from: Fire Doger on September 15, 2019, 12:59:04 pmuse a three way valve

author: mrpackethead
author_rank: Super Contributor
timestamp: September 15, 2019, 07:11:32 pm
content: Quote from: NorthGuy on September 13, 2019, 04:05:38 pmIts all about reliablity and speed. Firstly If you turn the vacumn off, it takes some time for the pressure to return to atmospheric, before the part will drop off. Applying a postive pressure, makes this happen considerably faster. And sometimes parts will stick to a nozzle. It removes the issue.

author: SMTech
author_rank: Frequent Contributor
timestamp: October 03, 2019, 08:13:13 am
content: Quote from: Kjelt on September 13, 2019, 03:42:01 pmI'd say they were thesehttps://www.smcusa.com/products/vacuum-products/vacuum-generators/ZA~51838in their manifold form with sensors & filters. The filters need changing at least annually & all sorts of other grot finds its way up the line between nozzle & filter so they need flushing sometimes too. SMC seems to have a selection of fairly similar devices, some of them might be better/cheaper/newer. Other large pneumatics companies may have something similar...

author: Bicurico
author_rank: Super Contributor
timestamp: October 03, 2019, 08:38:04 am
content: Noob question:As I understand it, this machine will just pick and place.So please explain:1) How do you setup the source of the components? How does the machine know where each resistor, etc. are positioned in the "stock"?2) The machine then picks the component and places it on the correct position. But how is it then soldered? With just a slight blow of air (for instance from the head moving nearby when placing some other component) a small resistor could be dislocated, I would imagine.Kind regards,Vitor