Screw from PCB side is impossible; no access. Also, since this is a redesign and the case involved is cast, I can add holes or remove material but not add material. That is a problem, too. Dwayne's product is pretty much exactly what I need albeit larger than I'd really like. Adhesives MAY be acceptable but reliability issues may preclude that. Mike H. On Fri, Jun 11, 2010 at 11:13 AM, RussellMc wrote: > I'm looking for a product (I'm reasonably sure it exists) which can be > affixed to a PCB to provide a conductive threaded anchor and standoff. > Soldered down is > okay, swaged may be better. Should be small- 2 to 2.5mm threaded hole with > an OD > as small as possible. > > ________ > > Your description doesn't seem to exclude the following as a possible > possibility. > As the nuts or threaded towers below are between the PCB and case and as > any > screw and 'nut' tightening happens prior to PCB insertion it seems to fit > inside rule set. > But, my parser may be broken :-). > > > World / Case // tower ( out-side / PCB / in-side ) > > 1. Is there enough room on the non-case side ("in-side") of the PCB for a > screw head, with screw facing through PCB towards wall.? > > This would allow you to insert a screw from the in-side through the PCB > into > a threaded tower on the PCB out-side. > The tower either has a thread protruding from the out-side to pass through > hole in case (may or may not violate the "screws can only come from > outside" > spec) OR has a threaded hole. ie standoff notionally could be a 4mm long > tube with a say 2mm internal threaded hold right through it. A 2mm flat > headed screw enters its in-side through the PCB and another threaded screw > enters its out-side via the case. > > Biggest issues seem to be > > - Total thread length inside rod for threaded portions of two > counter-inserted screws is 4mm. > > - Screw head on far side of PCB needs to be low enough to not annoy. > > 2. The super enthused extend thread length by using a hollow screw > inserted through the PCB. > Screw through PCB from in-side and add a nut (or towerlet) on out-side BUT > screw is hollow and threaded to form a tower for an external screw to > thread > into. Tower width this way is somewhat larger than other ways. > > *Could be achieved by drilling and tapping COTS screws with a smaller > internal hole. * > > 3. Is an adhesive based solution (at PCB end) tenable? Conductive > requirement makes that harder. > -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist