Cut Tape Feeders on the 7722FV

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ktownsend
 
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Cut Tape Feeders on the 7722FV

Post by ktownsend »

My MDC/Manncorp 7722FV should be here in a week or so, and I ordered a handful of cut tape feeders with it since the budget was fairly tight. Cut tape seems like a good compromise, though, in that I can't always justify an entire reel of expensive parts like crystals, etc., especially when there is only one per board. Most of my boards have about 25 unique parts and connectors, and that many reels would not only set me back a lot of money, but it would also be a pain to setup a traditional reel holder every time I need to change.

I'm just wondering if anyone here has any experience with the cut tape holders, though? My understand is that you need to get the picker very well centered so that it doesn't touch the tape or you risk knocking parts out of the reel. That's easy enough the first time around, but after you use 10 components or so you have to manually advance the tape, and I'm assuming this will throw your centering off ever so slightly.

Just wondering what kind of success or failure have had with the cut tape holders, though I'll post my own results when I get the machine in.

I ended up with the following setup to start with, for reference sake:

10 x 8mm feeders (for all the standard jellybean parts)
2 x 12mm feeders (SMA diodes, etc.)
15 x 8mm cut tape (for the more uncommon 1-2 per board parts)
4 x 12mm cut tape

I'll use the tray holder for anything larger using double-sided tape to hold any cut tape down (good tip Akiba).

Kevin.

blogger
 
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Re: Cut Tape Feeders on the 7722FV

Post by blogger »

My understand is that you need to get the picker very well centered so that it doesn't touch the tape or you risk knocking parts out of the reel
It's not too important as long as it doesn't HIT the tape when it goes down to pick something up. On my machine Z of 830-860 seems to work even on 0402 tapes. When you're reloading (reload tape prompt comes up) it has an overhead camera view with crosshair, so you can re-center the head over it just fine. what could be helpful there is adding part size rectangle as well, but not so important. there's no left/right motion on tape once its in the feeder, only up/down, so you're only centering it in one axis.

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ktownsend
 
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Re: Cut Tape Feeders on the 7722FV

Post by ktownsend »

Thanks for the update. I was wondering what happens when it gets to the end of the tape and if you're limited to 10 components. It seems you can use more you just need to advance the tape? It's annoying, but nice to know if you're really in a pinch.

I'm definately curious to try 0402 with the cut tape feeders to see what the hit/miss ratio is. I have a few boards where I'm using 0603 but could really use a bit more space and 0402 would be a much better fit.

Kevin.

blogger
 
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Re: Cut Tape Feeders on the 7722FV

Post by blogger »

Pickup of 0402 is not a problem at all. Never had parts lost or wasted due to machine.
Advancing the tape might be tricky without spilling parts, but if you peel the tape cover back just enough to open 20, then when its time to advance the tape, advance it first (still covered by clear tape), lock paper tape in place with screws, then carefully peel back the cover. Seems to work here.

isozee
 
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Re: Cut Tape Feeders on the 7722FV

Post by isozee »

blogger wrote what could be helpful there is adding part size rectangle as well, but not so important.
v2.0.12 added this feature. You can download it from MDC website http://www.mdc-smt.co.jp .
ISOZEE

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Re: Cut Tape Feeders on the 7722FV

Post by adafruit »

ktown/blogger, how do you attach the cuttape feeder to the machine? the one we have is just the plate - do you have an extra 80/20?

isozee
 
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Re: Cut Tape Feeders on the 7722FV

Post by isozee »

adafruit, yours may be just a prototype! Actually cut tape block(s) is mounted on tape cassette plate and snap in the feeder base.
CUT5.JPG
CUT5.JPG (87.4 KiB) Viewed 4207 times
you will get it soon.

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ktownsend
 
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Re: Cut Tape Feeders on the 7722FV

Post by ktownsend »

As Isono-san stated, they snap into place like any reel would. I have two blocks, one with 10x8mm and one with 5x8mm and 4x12mm. I haven't had a chance to try them yet (I just hooked the compressor up today), but I'll post some feedback here or on the wiki once I can try them out.

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ktownsend
 
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Re: Cut Tape Feeders on the 7722FV

Post by ktownsend »

After playing with the cut tape feeders a bit tonight I have mixed feelings about them. They are extremely sensitive to movement, and it's very easy to knock the components out, and it's a nightmare to fix them without knocking others out in the process. This isn't any fault of MDC's (they're very well machined), it's just the nature of tiny components in shallow cut tape. I was initially getting some components knocked out when the nozzle would go down to pick components up, but I noticed later than MDC recommends using a Z value 50-70 less than normal ... I've adjusted all the values and will do some more tests tommorow to see if I have more luck. Another poster mentionned this above, but I forgot about it when I ran my initial tests.

They're no replacement for real reels (which have performed flawlessly for me so far), but unfortunately not everyone is in a position to buy 30x8mm reels and cut tape may be the only reasonable solution. I've found certain components respond far better to the cut tape trays than others, mostly depending on how much free space the components have on the tape (the more there is the more likely the component is to jump out of the tray). Parts with tight-fitting holes on the tape seem to work better. I had some LEDs that I just gave up on and will manually place since if you looked at them the wrong way thay fell out of the rather large cavity in the tape, for example.

To minimize component loss, I've been leaving the plastic shield on all of the components except the last 2 or so (since I typically only need 1 or 2 parts per board). That way, if there is some vibration I only lose one or two components, and after each board I can pull the tape back a bit more. It's a bit slower, but still faster than manual assembly, and allows me to hold off a few months before buying more reels since the cost adds up very quickly (I'll eventually need about 10 more 8mm reels).

There is some shifting of the tape when you tighten the screws, but Isono san is aware of this since he contacted me about updating the holder for that.

One suggestion I have would be to add a bar to hold actual reels. It wouldn't cost very much extra, and would save you from having to cut the tape or change it every so often. Something to safely guide the excess tape down without touching the PCB tray might be useful, but I understand that it would add some cost and the objective of something like this is to save money. It's best to avoid shifting the PCB tray anyway since it's likely to knock components out even if it doesn't touch the tape.

Just some thoughts after my first night really using the machine. Now if I could just get SOT23 parts to place properly I'd be set. :-)

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