Author Topic: Lose SMD parts and PicknPlace machines....  (Read 4518 times)

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Offline YellofriendTopic starter

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Lose SMD parts and PicknPlace machines....
« on: October 01, 2017, 05:38:04 am »
I salvaged some SMD parts (Ta caps, SO-23, Cristal in MC306 case), it's a few 100 that I like to re-use.

ICs are no issue, they come on trays. But what is a good way to place those other small parts? Is there a good way to put them back in a reel?
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Offline SeanB

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Re: Lose SMD parts and PicknPlace machines....
« Reply #1 on: October 01, 2017, 04:52:20 pm »
Use old trays for them, and program the vision to pick them, though in many cases aside from the crystals they are not worth the hassle, or just use them for hand soldering repairs or manual rework.
 

Offline buck converter

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Re: Lose SMD parts and PicknPlace machines....
« Reply #2 on: October 01, 2017, 06:01:37 pm »
Sparkfun would put them in a bag and and sell it.
Just me and my scope.
 

Offline YellofriendTopic starter

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Re: Lose SMD parts and PicknPlace machines....
« Reply #3 on: October 02, 2017, 09:03:24 am »
Use old trays for them, and program the vision to pick them, though in many cases aside from the crystals they are not worth the hassle, or just use them for hand soldering repairs or manual rework.

My PnP doesn't do vision pickup. Mut I guess I could fix some reel tape to something solid.

Actually most parts go to the bin, but the LM4040 is $0.80, I prefer to keep those.
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Offline KL27x

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Re: Lose SMD parts and PicknPlace machines....
« Reply #4 on: October 04, 2017, 01:00:39 am »
Quote
Mut I guess I could fix some reel tape to something solid.

For SOT23, the problem is getting the tape stuck to a block/base. I have found that doublestick tape will protrude through holes on the bottom of the tape and cause failure of vacuum pickup of probably better than 1 in 20 parts.

I have milled a slot into a piece of HDPE to fit the cut tape, exactly. Then you can 1. screw a cover plate of FR-4 over it. You can mill/file a window in the cover plate barely wide enough to expose parts but to still hold down the edges of the cut tape (this helps prevent a bunch of parts to jump out if the tape gets hit; it has to be solid). Adjust tension so you can slide the tape through one end. (If it has the clear plastic still on, you can continually advance the tape by pulling on this cover.)

Or 2. you can make a "cut tape vice," by screwing a strip of FR-4 down so it just clamps on the top part of the tape, as long as you are using CNC pickup that isn't going to miss and disturb the tape.

To store a lot of parts, you can load used cut tape by taking the metallicized ESD bags and use a heatsealer to make a number of sleeves into it. Slide the cut tape partly in and start loading it up. Slide it into the sleeve as you go, and the part can't fall out. You have to get the fit just so, but it's not that particular.

Possibly my greatest invention for handling loose SOT parts, for packing your tray or tape block:
The orange bit is a "primer loading tray" or maybe a "primer flipping tray," which is sold from amazon/eBay and/or gun/reloading sites. It's used for flipping ammunition primers. It has little ridges in the bottom. So you just take the parts that are already rightside up, then when those run low/out, you give it a little shake and continue.

If you are going to build one, things that might not be obvious:
The orange tray is hot snotted to another plate of HDPE underneath to give a flatter surface.
The balls are 1/8", and the simple race is milled with 1/8" end mill to be just a hair over 1/8" wide and just a hair UNDER 1/8" deep. Then the top plate just rolls over it.
It might not be obvious, but you have to make the race small in diameter. If you tried to put the race all the way around the outer circumference of the plate, it won't spin freely. (You can see where I tried that, lol.) The mass and relative velocity of the balls will be too high (and more collisions between the balls, but that is probably secondary). Small clearance is what prevents the top tray from tilting. Also, don't fill the race all the way. It looks like I have lost a few, but it works better that way.
« Last Edit: October 04, 2017, 01:41:57 am by KL27x »
 

Offline vonnieda

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Re: Lose SMD parts and PicknPlace machines....
« Reply #5 on: October 23, 2017, 01:05:34 am »
@KL27x, love the parts lazy susan. Looks like a very quick way to sort em out! I'm curious, though, can you tell me what vacuum tool you are using? Looks self contained and nicely sized.

Thanks,
Jason
 

Offline KL27x

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Re: Lose SMD parts and PicknPlace machines....
« Reply #6 on: October 25, 2017, 06:40:59 am »
For a battery powered pickup, there's only one game in town AFAIK. The much beloved/maligned Hakko 394. You love it or you hate it.

It's undoubtedly one of the more costly combinations of a 2x AAA battery holder, spring contact push button, and maybe-$5.00-motor in existence, at retail of around $100.00. But I would buy again if I broke it.

I've had it for 4 years, mebbe? I haven't touched a vacuum pickup station since I bought this. I have a couple of others with the foot pedal and all that jazz. I know pushing a button bothers some people. I rarely use solder paste and oven, so I dunno. I don't do anything so precise with it as nestling a QFP onto precisely pasted pads. I am mostly dropping the parts onto fluxed pads, somewhere in the right zipcode. I do a pretty good amount of pcb assembly with it, and I have changed the batteries only once.

Quote
Looks like a very quick way to sort em out!
Until I buy a PnP machine (and probably even if I had one, I'd do this on smaller jobs not worth the setup time), it's not (primarily) for sorting salvaged parts. Loose pile of SOT parts is exactly how I prefer to use them in any volume assembly. I have given up on trying to use them out of the tape. It works perfectly when it works perfectly. But one bump and you lose a lot of parts and you spend a lot of time dealing with short lengths of tape. I just dump a pile of parts out of the tape at once and put them onto the board directly out of the SOT Susan. One part number at a time. Then dump them back into a coke can coaster or seal them into a bag when I'm done.

These videos might have had an influence:
I watched this before ever taking on this part of the process. Mike is spot on about handling SOT parts; I just took it one step further.


I can't find the other. It showed a "cartridge feed" pnp machine. I think that's what it was called. Instead of feeding from tape, it took a box filled with 100's of thousands of tiny SMD passives like resistors/caps, loose. The machine trickled them out over a tray, took a picture, and then picked up and neatly stacked hundreds per second into a magazine to keep the PnP fed while running.
« Last Edit: October 25, 2017, 07:55:15 am by KL27x »
 
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Offline nanofrog

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Re: Lose SMD parts and PicknPlace machines....
« Reply #7 on: October 25, 2017, 07:55:49 am »
The much beloved/maligned Hakko 394.
Wish I knew about that before I purchased a TV-1000 from Virtual Industries. It does the business, but I'd prefer cordless because if the hose catches a sauce cup, parts go flying.  |O
 

Offline Scyth3934

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Offline abeyer

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Re: Lose SMD parts and PicknPlace machines....
« Reply #9 on: July 20, 2023, 06:57:54 am »
That's quite the necro...

but I'll take the opportunity to snarkily observe that this thread seems to have a fundamental misunderstanding of PnP machines: They are designed to produce piles of loose smd components on your floor, not to consume them.
 
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Offline jmelson

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Re: Lose SMD parts and PicknPlace machines....
« Reply #10 on: August 03, 2023, 04:10:10 pm »
That's quite the necro...

but I'll take the opportunity to snarkily observe that this thread seems to have a fundamental misunderstanding of PnP machines: They are designed to produce piles of loose smd components on your floor, not to consume them.
Well, actually, they are not supposed to.  I just did a short run of a board with 22 parts on the back side.  I was amazed that is had ZERO mis-picks on the entire run for 704 parts!  That has never happened before.

But, to answer the original question, my feeders require me to discard the first couple parts when threading a new piece of cut tape.  If the parts are cheap (resistors, etc.) I just throw them in a bin.  If they are expensive (IC's) I set them aside, then back up the tape and put them back in the front of the tape.

Jon
 

Offline SMTech

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Re: Lose SMD parts and PicknPlace machines....
« Reply #11 on: August 03, 2023, 09:59:34 pm »
That's quite the necro...

but I'll take the opportunity to snarkily observe that this thread seems to have a fundamental misunderstanding of PnP machines: They are designed to produce piles of loose smd components on your floor, not to consume them.
Well, actually, they are not supposed to.  I just did a short run of a board with 22 parts on the back side.  I was amazed that is had ZERO mis-picks on the entire run for 704 parts!  That has never happened before.

But, to answer the original question, my feeders require me to discard the first couple parts when threading a new piece of cut tape.  If the parts are cheap (resistors, etc.) I just throw them in a bin.  If they are expensive (IC's) I set them aside, then back up the tape and put them back in the front of the tape.

Jon

Sometimes I wonder if the designers of SMT systems have looked at how people actually use them outside of the generic high volume nonstop lines. I have a client who uses a 1206 resistor that cost $15 each, 8 per board, there need to be more ways of handling parts like this where there is ZERO margin for a failed pick with no requirement for empty leader tape (splicing one on changes the pick height). As luck would have it the Essemtec feeder is quite good at picking from the first and last pocket of a strip but it is not perfect and is only half the problem. I just finished another board it had over 100 lines, about half of those were 1 or 2 per board for a very small batch, what do you think the purchasing for those looked like? Any half arsed solution a machine manufacturer has for that type of situation fails at that point, they only work for a small number of awkwardly packaged parts.
 

Online Mangozac

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Re: Lose SMD parts and PicknPlace machines....
« Reply #12 on: August 03, 2023, 11:26:53 pm »
Sometimes I wonder if the designers of SMT systems have looked at how people actually use them outside of the generic high volume nonstop lines. I have a client who uses a 1206 resistor that cost $15 each, 8 per board, there need to be more ways of handling parts like this where there is ZERO margin for a failed pick with no requirement for empty leader tape (splicing one on changes the pick height). As luck would have it the Essemtec feeder is quite good at picking from the first and last pocket of a strip but it is not perfect and is only half the problem. I just finished another board it had over 100 lines, about half of those were 1 or 2 per board for a very small batch, what do you think the purchasing for those looked like? Any half arsed solution a machine manufacturer has for that type of situation fails at that point, they only work for a small number of awkwardly packaged parts.
Isn't that supposed to be the Mydata/Mycronic niche? I had their feeder design demonstrated to me earlier this year and it seemed pretty cool the way it peels away the tape, so you can easily feed in cut tape with no loss.
 

Offline SMTech

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Re: Lose SMD parts and PicknPlace machines....
« Reply #13 on: August 04, 2023, 07:50:58 am »
Sometimes I wonder if the designers of SMT systems have looked at how people actually use them outside of the generic high volume nonstop lines. I have a client who uses a 1206 resistor that cost $15 each, 8 per board, there need to be more ways of handling parts like this where there is ZERO margin for a failed pick with no requirement for empty leader tape (splicing one on changes the pick height). As luck would have it the Essemtec feeder is quite good at picking from the first and last pocket of a strip but it is not perfect and is only half the problem. I just finished another board it had over 100 lines, about half of those were 1 or 2 per board for a very small batch, what do you think the purchasing for those looked like? Any half arsed solution a machine manufacturer has for that type of situation fails at that point, they only work for a small number of awkwardly packaged parts.
Isn't that supposed to be the Mydata/Mycronic niche? I had their feeder design demonstrated to me earlier this year and it seemed pretty cool the way it peels away the tape, so you can easily feed in cut tape with no loss.
Is it no loss? It has been a while since I've seen one in person but that blade does start a little way back, I would be concerned about parts behind the pick position. You will notice in the brochure, they have a tape strip holder much as you now find on most other platforms, how well they work in practice is another matter. The platform has its own drawbacks, there are more than one type of Agilis finger for each tape size to handle the different types of tape and component pitch, for the concept to work you already have to own lots of them, and that means owning even more. It is an awesome platform though that clearly really works for many companies although there was an interesting amount of negative feedback in a thread on SMTnet recently to do with a historic high level of maintenance required.
 

Offline MR

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Re: Lose SMD parts and PicknPlace machines....
« Reply #14 on: August 04, 2023, 08:10:06 am »
I looked at some MyData videos it must have loss the way it is - certainly someone can carefully handle the tape and it might be okay.

No loss would probably be if the plastic is directly peeled off in front of the pickup area.
I have manufactured my own 8mm feeders, I have a spacing between the pickup area and the peeling position of around 5mm - so every time I assemble 5mm are lost so far.
I think about modifying some of them so I can peel the plastic directly in front of the pick up area. I used a machine which did it that way and it worked okay (except that the machine used gang spooling and that mechanism itself sucked).
I sometimes extended the plastic with glue if it was too short.

I have done some experiments of pushing the plastic tape aside and only peeling it off on one side (the experiments succeeded), it's still no guarantee that components will stay there.
 

Offline jmelson

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Re: Lose SMD parts and PicknPlace machines....
« Reply #15 on: August 04, 2023, 05:46:14 pm »

I have manufactured my own 8mm feeders, I have a spacing between the pickup area and the peeling position of around 5mm - so every time I assemble 5mm are lost so far.
Both my previous Philips CSM84 and my current Quad QSA30A (made by Samsung) peel the tape JUST behind the pick-up location.  It was possible on the Philips to not have to dump any parts.  On the Quad I have to dump just a FEW, but the back-up capability of the electronic feeders make it quite easy to back up the tape and drop those parts in the tape.  This is only an issue with cut tape with no leader.  When I take tapes off the machine I leave some leader (empty carrier tape and cover tape) and do not lose ANY parts, if I handle it carefully.  I can then rethread later and use the first part on the tape.
Jon
 


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