Component kits supplied by clients

WARNING: KITTING ERRORS WITHIN CLIENT SUPPLIED COMPONENT KITS

Errors in client supplied kits are the most frequent causes of production delay.  Do not trust your component supplier.  The component distributor's error rate is over 2%.  Do not send us component kits directly from distributors without double checking their accuracy.  We may find kit supply errors but we do not warrant that we will.  We may not identify wrongly labeled components.  An error in a free-issue kit supplied to us is your error.  We will fit the parts you supply to us. Rectification costs attributable to wrongly supplied parts are additional to our quoted prices.

You may like to consider the advantages of getting us to supply your components. If we supply kits, we take responsibility for all incoming kitting checks, and we guarantee that the all components will be supplied and fitted exactly as your Bill of Materials.  Our buying power may make it more cost effective for us to supply your kit.  Take a look at the pros & cons of supplying free issue kits.

Ask us to quote for you component kit.

Bill of Materials (BOM)

A clear and accurate Bill of Materials must be provided.  It is invaluable for clarity to include Farnell part numbers.  Different types of components should be listed in groups, i.e. 0805 10nf's sequentially, then 0805 100nf's etc.  Component values should be clear e.g. 100R, 100K, 100M etc, and not just "100" printed as the value.  BOMs must clearly identify parts as either "customer supplied", "Newbury supplied" or "not fitted".

Check kits before shipment

Component kits must be physically checked against the BOM before shipment to us. Count the parts and check that the quantity agrees with your BOM. The component in each packet must be checked against the attached label. Ever digit in the part reference must be checked, including the tolerance and voltage rating. Finally, a check must be made that the component footprint matches the PCB pads.

Component spares

Component kits must be supplied with extra (spare) parts to allow for losses and wastage. 5% extra spares is a reasonable guideline.  It is the nature of pick  & place machine feeders that parts are wasted at the beginning and end of reels. If we are not supplied with spare parts, we may short ship completed or part built PCBs.  Surplus parts will be returned.

Component packaging

Where possible, all SMD components must be supplied taped and reeled.  Parts must be supplied in anti-static component bags (generally pink or silver in colour).  No static generating materials are permitted on our production floor.

Component packages or bags must be marked as follows:

- parts list item number and/or location designator (e.g. C5)
- quantity
- device description and code
- fine pitch devices must be packaged to avoid damage to their legs.
- moisture sensitive devices must be supplied in sealed bags.
- shipping notes must be included with all parts supplied 

PCB Pick & place data

It is essential to send us component placement data.  This data should include:
- CAD x/y coordinate data in .prn, .csv, .xls, or other editable format.

CAD x/y data must contain columns that include:
- part number (e.g. 1206100NF)
- reference designator (e.g. C12)
- x /y coordinates
- theta rotation angle (e.g.90 deg.)
- placement surface (e.g. top or bottom) 

We need easily machine readable data with "one reference designator per line", similar to this format:

Ref Deg                    Part No.              Other info / footprint etc
C1                           0805100NF          CAP0805 X7R
C2                           0805100NF          CAP0805 X75
C3                           0805100NF          CAP0805 X75
C4                           0805100NF          CAP0805 X75
C5                           0805100NF          CAP0805 X75

The format example below with "multiple reference designators per line" is a problem to machine read accurately, and is to be avoided:

Ref Degs                     Part No.             Qty
C1,C2,C3,C4,C5           0805100NF          5

Component ident data

Silkscreen, (legend or component ident)  data should already be in our possession within the bare PCB manufacturing data package.  If not, send the data to cadcam@newburyassembly.co.uk .  A schematic diagram of your layout will assist us to resolve any ambiguities about component polarity and physical placement.  Send the data to cadcam@newburyassembly.co.uk

Assembly policies

We will use our best endeavours to place all client supplied parts.  Clients have responsibility for supplying a clean kit of parts and for any additional costs arising from client supplied component kit errors.  In respect of PCB Train supplied Rs and Cs, where non-standard component values are called for (e.g.123 ohms), we will fit the nearest E24 value such as 120 ohms.  Customer supplied components that do not correctly fit the PCB footprint will either be modified to fit (if economic) or returned unplaced with the assembly.  Badly labeled components that cannot be cross-referenced to the parts list will be returned to clients with the assembly.  If an unclear drawing and/or placement diagram is supplied, we will attempt to contact you and ask you to clarify the information.  Parts with ambiguous placement locations may be left unplaced and returned with the assembly.

Quality standards

We will build your Printed Circuit Boards to standard commercial quality (using specification IPC-A-610 Rev C - Class 1, Acceptability of Electronic Assemblies) as a guideline. If you require a higher level of quality , e.g. class 2, or class 3, for military, medical or other purposes then please contact us for a quote.

Whilst every effort is made to ensure that you receive a fully functional electronic assembly, we can inspect PCB assemblies at a visual level only. If a fault is subsequently found as a result of an assembly error then we will rework the assembly without charge.

A no-clean 2% silver loaded solder wire will be used for all hand assembly. The colophony- free flux contained within this wire will leave a slight "white-powdery" inert residue around the solder joints. This is non-corrosive and is acceptable within most commercial applications.

PCB / Assembly Design

BGA footprint pads must be solder resist dammed to ensure adjacent via holes do not wick solder away from the solder ball.  Do not put via holes in BGA pads or indeed in any SMD pads.  Via holes should be tented or covered with solder resist especially under BGA's to avoid solder paste wicking.