PCB Manufacture Questions - Wave or Reflow this board?

[oddbudman]

Hey fellow eda folks

I'm looking to get a board mass manufactured and just need some help wrt which manufacturing method to choose.

I've been doing some reading and i'm a little unsure if this board will need to be reflow soldered on the top and wave soldered on the bottom, or if wave soldering can be used on both the top and bottom of the board.

Bear with me this is my 1st time looking to get something mass manufactured.

The board uses a mixture of smt components (top side only) and through hole components.

The board is fairly simple, attached is a picture of it.

If you have any suggestions wrt what will be the cheapest method of mass manufacture, or have any experiences/insights you want to share with me I would be most interested in hearing them.

Look foward to some replies.

thx
oddbudman

 

[M!k]

Top: reflow
Bottom: wave
Soldering SMDs by a wave is sometimes possible but can cause some problems. So this should only be done if there are additional SMDs on the bottom of your PCB.


Mik

 

[mImoto]

Yes, top reflow and botton wave. Why to use reflow for bottom side if you have not smd components. Reflow bottom I think that it is needed when you have complex SMD chips on the bottom side. If you have also just resistors, caps, etc. many people also use wave for bottom.

Regards,

mimoto

 

[atmaca]

for smd components reflow owen is required. Because you use cream-solder for smd components.
For through hole components wave soldering is required.

thanks

 

[mkbs]

I agree with mImoto,
top reflow and botton wave.
Sometimes I have components on Bottom side too, so I'm using Top reflow and bottom wave (with glue components).
For information only, I have put also a QFP 64p on botton side with wave,without
problems.

MKBS

 

[Frosty]

You are going to have several problems here.

1. The board is too small, you should panel the board up to around 200x200mm, its too small to use in a conveyer. Circuit breakout is up to you (vscore, mouse nibbles etc)

2. The board has no fiducial markings, please add at least one fiducial marking per corner around 1mm dia top layer pad and expand solder mask around it by 1mm also.

3. Add a 10mm waste strip to each side and also a 3.5 or 4mm unplated tooling hole 5mm in from each corner (some place machines need this)

4. For your QFP on the bottom side, using wave, place at 45 degrees and also make special footprint with for additional pads so that the final 'flowed' pad is not on the QFP itself to avoid shorts, these pads should consider the conveyer direction across solder bath and if multiple wave will be used. Please advise your QFP pitch. For fine pitch you might have to reflow BOTH sides and have special wave solder frame made to 'mask' off the reflowed parts on bottom.

Hope some of this helps you

:F

 

[oddbudman]

Thanks for all the replies.

Thanks especially to Frosty, I found your post to be very insightful

Frosty (or anyone else), are there any texts that you can recommend me read to find out more about all the stuff you mentioned? Especially in regards to fiducial markings, waste strips, tooling holes and PCB breakout techniques?

I already have the IPC-SM-782A Standard and the IPC-2221 Standard.

I'm sorta all alone on this project so any assistance / experiences / advice you want to share would be much appreciated.

Thanks everyone for your help.

oddbudman

 

[kot_b]

I can recomend you to look on Philips semiconductor web, for information about soldering.
Our guy's as fiductional marks often use component pads. Breakout we often use as 5mm on side of the panel.

 

[Frosty]

Thanks for all the replies.

Thanks especially to Frosty, I found your post to be very insightful

Frosty (or anyone else), are there any texts that you can recommend me read to find out more about all the stuff you mentioned? Especially in regards to fiducial markings, waste strips, tooling holes and PCB breakout techniques?

I already have the IPC-SM-782A Standard and the IPC-2221 Standard.

I'm sorta all alone on this project so any assistance / experiences / advice you want to share would be much appreciated.

Thanks everyone for your help.

oddbudman

http://www.tkb-4u.com/articles/other/fiducial/fiducial.php

**broken link removed**

Might be of some more help to you

:F