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# Tool to measure SMT component reel quantity

H Watson

Tool to measure SMT component reel quantity | 3 January, 2003

I was wondering if anyone knows of a tool, like a depth gauge, that is designed to measure the component count of partial SMT component reels. Most reels have a built in indicator gauge, but several do not. A tool would be handy for our physical inventory. Any information would be greatly appreciated. Thanks in advance.

HW

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Jon Fox

Tool to measure SMT component reel quantity | 3 January, 2003

We use this for our measurements: N=(17000(D^2-d^2))/(C*P)

N=number of parts on reel D=OD of carrier tape on reel (inches) d=OD of reel core (inches) C=thickness of carrier tape (mils) P=pocket pitch (millimeters)

example: 6"OD on 3" core of 40-mil carrier tape at 4mm pitch... 17000(36-9)/(40*4)=459000/160=~2870 parts

Tool to measure SMT component reel quantity | 3 January, 2003

This tool is what you want, been using them for 9 yrs or so and am very happy with there product. http://www.vtekusa.com/pc250.htm

Tool to measure SMT component reel quantity | 4 January, 2003

Tool to measure SMT component reel quantity | 6 January, 2003

We always hate ourselves when we do this, because it always ends-up laying our guts on the table for someone to stomp on, but we just can�t help ourselves.

We do not obtain the same results from both Jon's and Ashok's approaches. Maybe our math in wrong, but before anyone dedicates themself to one formula or the other, they should consider its accuracy.

Tool to measure SMT component reel quantity | 6 January, 2003

I feel an SMTA vision award coming on. A depth guage sounds like a great idea (especially one designed specifically for that purpose). It should readout "components remaining". But until that product is avaialble, why not just save some of the empty reels with the component counts and simply lay them on top of the partial reels and use them as a guage. It sounds like accuracy is not the major concern here.

Tool to measure SMT component reel quantity | 6 January, 2003

I just had a better idea, why not make your own template. A cylindrical guage printed out on a piece of mylar. A series of concentric rings with a quantity on each ring. Use it as an overlay.

Jon Fox

Tool to measure SMT component reel quantity | 6 January, 2003

Not that easy, because of different thicknesses and pitch, almost no two reels are the same unless they have a common vendor and part type. That would require a mylar template for every vendor and for every pitch variant. We sometimes get parts from as many as 4 different vendors. I like the idea of the counting machine. Had one at my last place and would love to have one now. We are getting ready to do our yearly inventory.

Tool to measure SMT component reel quantity | 6 January, 2003

That is true. But maybe for discreets in paper tape where the bulk of your partially used reels is it may be helpful. The rest you can guestimate. Not very good of course. As a placement machine manufacturer I agree every machine should have real time inventory information available as does our new machine. It will save alot of time counting and verifying in the long run.

Tool to measure SMT component reel quantity | 6 January, 2003

This is getting deep but here's my input:

Here's an idea....... Get a full reel and weigh it on a parts scale down in the stock room. Next weigh an empty reel. Subtract empty from full, and devide this value by the quantity of the full reel. This will give you the weight of the part and its associated cover tape and carrier tape. Now weigh the reel in question and devide it by this value. Aproximate quantity achieved with no calculus needed. The only thing that will through off this calculation a little is the extra chunk of empty tape in the beginning.

Garth

Tool to measure SMT component reel quantity | 15 January, 2003

Buy an electronic counter and simply spool your partial reels to an empty reel. It takes my staff a couple of hours to count every component on partial reels (~50 different values) and I have an exact number rather than an estimate.

Eugene

Tool to measure SMT component reel quantity | 17 July, 2003

Hi Greg,

I have the same idea, but my dilema is reel come in different size, thickness, pitch...etc. Did you make one up? could you share those information with me.

Thanks, Eugene

James

Tool to measure SMT component reel quantity | 18 July, 2003

Just got a demo in for a VTECH 250+, it is fast and easy to use. I have tried others but nothing beats this one. Great buy for using for inventory control.