OK, it looks like there's some help needed here. There are typically three ways to soldermask a hole. All three can be done by "most" board shops. All three can be done by outside services who specialize in soldermask or epoxy services. To help interpret what one may call "soldermasking" a hole I will list them below. TENT. Tenting a hole is putting a cover over the hole "tent" this is typically done with Dry Film. Why? because you want to cover over the entire surface without dimpling into the hole. LPI can not do this. LPI can plug and sometimes fill but it cannot tent. After dry film (or similar) tent one usually then coats the entire part with LPI soldermask. PLUG. Plugging a hole is done by filling the hole with soldermask or an epoxy. With a plugged hole one would not see light thru the hole but there may be dimpling on the surface or there may be some voids in the "plug". FILL. Filling a hole implies to "completely" fill the hole with a soldermask or an epoxy material. Filling is regularly done with conductive via fill. When one discusses via in pad technology they are speaking of filling the hole with conductive epoxy. Filling is also regularly done with specialized non-conductive epoxies. A filled hole would have no to minimal dimpling on the surface and would have no or minimal voids in the hole fill material. I hope this helps. James Hofer Director of Operations Accurate Circuit Engineering 3019 S. Kilson Dr. Santa Ana Ca. 92707-4202 714-546-2162 work 714-473-6127 cell [log in to unmask] ----- Original Message ----- From: "Jim Henderson" <[log in to unmask]> To: <[log in to unmask]> Sent: Friday, August 27, 2004 12:22 PM Subject: Re: [TN] tented Via > Cal, > > I know quite a bit of board houses, including us, use spray coaters for > applying our LPI. The finished thickness of that is .0008 to .001. So > there is very little chance that will plug your via hole. We have to plug > via holes as a separate screen printing process. If to plug or tent the vi as > is called out on your drawing this is how we would do it. Good luck. > > Jim > > -----Original Message----- > From: TechNet [mailto:[log in to unmask]]On Behalf Of Cal Driscoll > Sent: Friday, August 27, 2004 1:15 PM > To: [log in to unmask] > Subject: [TN] tented Via > > > Hello All- > > I am not a board fab person but would like to understand why some LPI > masking processes can not tent vias (non filled). > > We have a board house that can tent vias with no issues. When we went to > another board house the are unable to tent vias. Both shops are huge and > have international locations. I would think the technology would be there to > do this. > > thanks in advance, > Cal > www.ctdi.com > > --------------------------------------------------- > Technet Mail List provided as a service by IPC using LISTSERV 1.8e > To unsubscribe, send a message to [log in to unmask] with following text in > the BODY (NOT the subject field): SIGNOFF Technet > To temporarily halt or (re-start) delivery of Technet send e-mail to > [log in to unmask]: SET Technet NOMAIL or (MAIL) > To receive ONE mailing per day of all the posts: send e-mail to > [log in to unmask]: SET Technet Digest > Search the archives of previous posts at: http://listserv.ipc.org/archives > Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 > for additional information, or contact Keach Sasamori at [log in to unmask] or > 847-509-9700 ext.5315 > ----------------------------------------------------- > > --------------------------------------------------- > Technet Mail List provided as a service by IPC using LISTSERV 1.8e > To unsubscribe, send a message to [log in to unmask] with following text in > the BODY (NOT the subject field): SIGNOFF Technet > To temporarily halt or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL) > To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest > Search the archives of previous posts at: http://listserv.ipc.org/archives > Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 > ----------------------------------------------------- > --------------------------------------------------- Technet Mail List provided as a service by IPC using LISTSERV 1.8e To unsubscribe, send a message to [log in to unmask] with following text in the BODY (NOT the subject field): SIGNOFF Technet To temporarily halt or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL) To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest Search the archives of previous posts at: http://listserv.ipc.org/archives Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 -----------------------------------------------------