Hi Jeff
As one of few dispensing full time instead of printing ;
just few comments :
If you have already printer , than yes , "screen the paste rather than
dispensing " could make sense from point of stretching established
process versatility, therefore depreciated economy .
Otherwise , if you match dispenser speed (4x ; up to 120K d/h) to p&p
speed , there is nothing like it .
Also, do not believe dispensing alone may not provide the additional
volume required to fill the hole .
Perhaps printing ( stencil ) has been meant, when I've seen the comment
.
One of the major reasons to go with dispenser , has been it's ability to
place ANY amount of paste anywhere, in total freedom from stencil's
inherent limitations . Optimal for TH through reflow mix .
Kathy seems to be on right track from getting utmost from existing
process ;
the art on stencils, if you are forced that way by established process,
is you actually can stencil way into masked area if you need to gain
more paste for TH ; say in parallel extension spikes in case of
connectors ;
on reflow the metal pulls back to pad .
Watch the component on top ; establish the flow back ways do work , by
cutting them you'd get yourself nice big balls .
You just have to give it bit of thought on the geometry of the travel ;
play (carefully) with top set heatgun over graded design board to
establish final stencil cut optimum .
1
Not easy on materials through reflow , Alcatel makes few which don't
melt ;
must be more of them round .
2
feeders are easy, existing, tubes, big reels, if you can pick it up .
tapes ; you have over there a lot of custom tapers , a luxury I envy you
.
Check the mag's usually they advertise a lot ; or say Nepcon's directory
's got them by dozens .
See you paul
>----------
>From: Jeff Hempton[SMTP:[log in to unmask]]
>Sent: Friday, 10 April 1998 7:18
>To: [log in to unmask]
>Subject: [TN] paste-in-hole components
>
> Greetings fellow Technetters,
> I am in the beginning throes of implementing serious paste-in-hole
> (PIH) here at UT. I have some limited experience/success in this area,
> but would like to tap into some of you PIH users that have been
> involved longer, and are Grand Wizards of the PIH process:
> 1) Could you please forward any info you can share on component
> suppliers that are manufacturing/willing-to-manufacture leaded
> components (connectors,etc.) for this process?
> 2) Same question for feeder manufacturers, taping houses, etc.
>
> If you are a vendor, please respond to me directly instead of
> replying to Technet. ANY info shared would be DEEPLY appreciated.
> Thanx in advance!
>
> United Technology Electronic Controls
> Jeff L. Hempton, Sr. SMD Engineer
> 3650 West 200 North
> Huntington, In
> 46750-9002
> Phone: 219-359-3514
> Fax: 219-358-0695
> E-mail: [log in to unmask]
>
>################################################################
>TechNet E-Mail Forum provided as a free service by IPC using LISTSERV 1.8c
>################################################################
>To subscribe/unsubscribe, send a message to [log in to unmask] with following
>text in the body:
>To subscribe: SUBSCRIBE TechNet <your full name>
>To unsubscribe: SIGNOFF TechNet
>################################################################
>Please visit IPC web site (http://jefry.ipc.org/forum.htm) for additional
>information.
>For the technical support contact Dmitriy Sklyar at [log in to unmask] or
>847-509-9700 ext.311
>################################################################
>
>
################################################################
TechNet E-Mail Forum provided as a free service by IPC using LISTSERV 1.8c
################################################################
To subscribe/unsubscribe, send a message to [log in to unmask] with following text in the body:
To subscribe: SUBSCRIBE TechNet <your full name>
To unsubscribe: SIGNOFF TechNet
################################################################
Please visit IPC web site (http://jefry.ipc.org/forum.htm) for additional information.
For the technical support contact Dmitriy Sklyar at [log in to unmask] or 847-509-9700 ext.311
################################################################
|
