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impossible stud

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  impossible stud John Larkin <jjlarkin@highlandtechnology.com> - 2018-04-19 20:51 -0700
    Re: impossible stud Perry <Perry@null.com> - 2018-04-20 12:41 +0800
      Re: impossible stud Perry <Perry@null.com> - 2018-04-20 12:47 +0800
      Re: impossible stud TTman <kraken.sankey@gmail.com> - 2018-04-20 11:13 +0100
      Re: impossible stud George Herold <gherold@teachspin.com> - 2018-04-20 06:10 -0700
        Re: impossible stud gnuarm.deletethisbit@gmail.com - 2018-04-20 22:29 -0700
    Re: impossible stud "Tim Williams" <tiwill@seventransistorlabs.com> - 2018-04-20 02:07 -0500
      Re: impossible stud John Larkin <jjlarkin@highlandtechnology.com> - 2018-04-20 07:14 -0700
    Re: impossible stud Martin Brown <'''newspam'''@nezumi.demon.co.uk> - 2018-04-20 08:41 +0100
      Re: impossible stud John Larkin <jjlarkin@highlandtechnology.com> - 2018-04-20 07:22 -0700
        Re: impossible stud tabbypurr@gmail.com - 2018-04-20 07:38 -0700
          Re: impossible stud John Larkin <jjlarkin@highlandtechnology.com> - 2018-04-20 08:29 -0700
            Re: impossible stud "Carl Ijames" <carl.ijames@NOverizon.net> - 2018-04-20 11:50 -0400
              Re: impossible stud John Larkin <jjlarkin@highlandtechnology.com> - 2018-04-20 09:41 -0700
                Re: impossible stud "Carl Ijames" <carl.ijames@NOverizon.net> - 2018-04-20 14:05 -0400
                Re: impossible stud whit3rd <whit3rd@gmail.com> - 2018-04-20 12:39 -0700
                  Re: impossible stud John Larkin <jjlarkin@highland_snip_technology.com> - 2018-04-20 16:44 -0700
                    Re: impossible stud George Herold <gherold@teachspin.com> - 2018-04-20 16:54 -0700
                      Re: impossible stud John Larkin <jjlarkin@highland_snip_technology.com> - 2018-04-20 17:41 -0700
                        Re: impossible stud George Herold <gherold@teachspin.com> - 2018-04-20 18:55 -0700
              Re: impossible stud Jeff Liebermann <jeffl@cruzio.com> - 2018-04-20 10:26 -0700
                Re: impossible stud John Larkin <jjlarkin@highland_snip_technology.com> - 2018-04-20 12:16 -0700
                  Re: impossible stud Jeff Liebermann <jeffl@cruzio.com> - 2018-04-20 17:52 -0700
                  Re: impossible stud piglet <erichpwagner@hotmail.com> - 2018-04-21 10:45 +0100
                    Re: impossible stud John Larkin <jjlarkin@highlandtechnology.com> - 2018-04-21 07:53 -0700
                      Re: impossible stud Joseph Gwinn <joegwinn@comcast.net> - 2018-04-21 15:00 -0400
                        Re: impossible stud John Larkin <jjlarkin@highlandtechnology.com> - 2018-04-21 15:23 -0700
                          Re: impossible stud Joseph Gwinn <joegwinn@comcast.net> - 2018-04-22 12:39 -0400
                            Re: impossible stud John Larkin <jjlarkin@highlandtechnology.com> - 2018-04-22 10:19 -0700
                              Re: impossible stud Joseph Gwinn <joegwinn@comcast.net> - 2018-04-24 10:07 -0400
                                Re: impossible stud John Larkin <jjlarkin@highlandtechnology.com> - 2018-04-24 07:58 -0700
                                  Re: impossible stud Joseph Gwinn <joegwinn@comcast.net> - 2018-04-24 22:38 -0400
                                    Re: impossible stud John Larkin <jjlarkin@highland_snip_technology.com> - 2018-04-25 10:31 -0700
                                  Re: impossible stud gnuarm.deletethisbit@gmail.com - 2018-04-25 14:44 -0700
                      Re: impossible stud Joe Chisolm <jchisolm6@earthlink.net> - 2018-04-21 14:44 -0500
                      Re: impossible stud whit3rd <whit3rd@gmail.com> - 2018-04-21 14:11 -0700
                  Re: impossible stud tabbypurr@gmail.com - 2018-04-21 03:18 -0700
                    Re: impossible stud tabbypurr@gmail.com - 2018-04-21 03:34 -0700
            Re: impossible stud Joseph Gwinn <joegwinn@comcast.net> - 2018-04-20 12:41 -0400
            Re: impossible stud "Tim Williams" <tiwill@seventransistorlabs.com> - 2018-04-20 20:35 -0500
            Re: impossible stud bill.sloman@ieee.org - 2018-04-20 19:00 -0700
    Re: impossible stud Jasen Betts <jasen@xnet.co.nz> - 2018-04-20 08:12 +0000
      Re: impossible stud Mike Perkins <spam@spam.com> - 2018-04-20 10:26 +0100
        Re: impossible stud "dcaster@krl.org" <dcaster@krl.org> - 2018-04-20 07:09 -0700
      Re: impossible stud John Larkin <jjlarkin@highlandtechnology.com> - 2018-04-20 07:23 -0700
    Re: impossible stud Jeff Liebermann <jeffl@cruzio.com> - 2018-04-20 10:13 -0700
    Re: impossible stud Lasse Langwadt Christensen <langwadt@fonz.dk> - 2018-04-20 14:17 -0700
    Re: impossible stud Jim Thompson <To-Email-Use-The-Envelope-Icon@On-My-Web-Site.com> - 2018-04-20 15:08 -0700
      Re: impossible stud John Larkin <jjlarkin@highland_snip_technology.com> - 2018-04-20 16:48 -0700
        Re: impossible stud Joe Chisolm <jchisolm6@earthlink.net> - 2018-04-20 23:17 -0500
    Re: impossible stud "Tim Williams" <tiwill@seventransistorlabs.com> - 2018-04-20 20:20 -0500
    Re: impossible stud mickgeyver <alan.yeager.2013@gmail.com> - 2018-04-20 18:41 -0700
    Re: impossible stud Robert Baer <robertbaer@localnet.com> - 2018-04-21 00:53 -0700
    Re: impossible stud Lasse Langwadt Christensen <langwadt@fonz.dk> - 2018-04-21 13:06 -0700
      Re: impossible stud John Larkin <jjlarkin@highlandtechnology.com> - 2018-04-21 15:29 -0700
        Re: impossible stud Lasse Langwadt Christensen <langwadt@fonz.dk> - 2018-04-21 15:46 -0700
    Re: impossible stud Spehro Pefhany <speffSNIP@interlogDOTyou.knowwhat> - 2018-04-24 09:10 -0400
      Re: impossible stud John Larkin <jjlarkin@highlandtechnology.com> - 2018-04-24 06:55 -0700
        Re: impossible stud Joe Chisolm <jchisolm6@earthlink.net> - 2018-04-24 11:00 -0500

Page 3 of 3 — ← Prev page 1 2 [3]

#503060

On Saturday, April 21, 2018 at 1:29:19 AM UTC+10, John Larkin wrote:
> On Fri, 20 Apr 2018 07:38:42 -0700 (PDT), tabbypurr@gmail.com wrote:
> 
> >On Friday, 20 April 2018 15:22:28 UTC+1, John Larkin  wrote:
> >> On Fri, 20 Apr 2018 08:41:23 +0100, Martin Brown
> >> <'''newspam'''@nezumi.demon.co.uk> wrote:
> >> >On 20/04/2018 04:51, John Larkin wrote:
> >> >> I want a lot of these:
> >> >> 
> >> >> https://www.dropbox.com/s/dmj4vff7mnldrcs/Impossible_Stud.JPG?raw=1
> >> >> 
> >> >> It probably doesn't exist. Maybe a Swiss screw machine company could
> >> >> make us a bucket full of these.
> >> >
> >> >Not quite what you asked for but how about getting some threaded bar and 
> >> >turning down to the other size and using a nut to make the collar.
> >> >Or don't turn it down at all and use a larger countersunk screw.
> >> >
> >> >If you did it in copper or brass then they could be soldered in to the 
> >> >daughter board and so wouldn't need to be a tight press fit.
> >> 
> >> Yes, one option would be to delete the knurl and solder one end. I
> >> want the botton of the baby board to be essentially planar, but a
> >> little solder bump would probably be OK.
> >> 
> >> >> 
> >> >> Six of these would press into a small PCB, which could then be bolted
> >> >> onto the bottom of a bigger PCB.
> >> >
> >> >Does it really need 6 of these supports? I don't envy production putting 
> >> >it together. Wouldn't 3 or 4 thicker ones be much easier to assemble?
> >> 
> >> They are electrical connections too. I need six connections between
> >> boards. The baby board is about 0.5" on a side.
> >> 
> >> https://www.dropbox.com/s/dsjwdnize4ig2gx/Impossible_App.JPG?raw=1
> >
> >I'd hate to rely on solder for a mechanical connection. I know consumer stuff does it routinely, but we've all seen the reliability problems that result.
> >
> >
> >NT
> 
> The old Radio Amateur's Handbook admonished against using solder as
> mechanical support. Then Tektronix did it everywhere in their old tube
> scopes.
> 
> Paul Revere soldered the handles onto teapots. Who is going to argue
> with Paul Revere?

Paul Revere was a silver-smith. Silver-soldering, also known as hard soldering or brazing, produces much more robust joints.

Nobody is going to argue with Paul Revere, but you've invoked him in an area where you should have known that he wasn't the relevant authority.

-- 
Bill Sloman, Sydney 

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#503008

On 2018-04-20, John Larkin <jjlarkin@highlandtechnology.com> wrote:
> I want a lot of these:
>
> https://www.dropbox.com/s/dmj4vff7mnldrcs/Impossible_Stud.JPG?raw=1
>
> It probably doesn't exist. Maybe a Swiss screw machine company could
> make us a bucket full of these.

how do you prevent them from pulling out when the nut is tightened?

-- 
     ت

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#503010

On 20/04/2018 09:12, Jasen Betts wrote:
> On 2018-04-20, John Larkin <jjlarkin@highlandtechnology.com> wrote:
>> I want a lot of these:
>>
>> https://www.dropbox.com/s/dmj4vff7mnldrcs/Impossible_Stud.JPG?raw=1
>>
>> It probably doesn't exist. Maybe a Swiss screw machine company could
>> make us a bucket full of these.
> 
> how do you prevent them from pulling out when the nut is tightened?

That was my thought, there are reasons why you can't get these 
off-the-shelf.

Perry's link is most useful.



-- 
Mike Perkins
Video Solutions Ltd
www.videosolutions.ltd.uk

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#503017

On Friday, April 20, 2018 at 5:26:17 AM UTC-4, Mike Perkins wrote:
.
> > 
> > how do you prevent them from pulling out when the nut is tightened?
> 
> That was my thought, there are reasons why you can't get these 
> off-the-shelf.
> 
> Perry's link is most useful.
> 
> 
> 
> -- 
> Mike Perkins
> Video Solutions Ltd
> www.videosolutions.ltd.uk

Try searching on " brass standoffs " on AllpExpress.  ( or ebay or Amazon  )

                                        Dan

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#503020

On Fri, 20 Apr 2018 08:12:00 -0000 (UTC), Jasen Betts
<jasen@xnet.co.nz> wrote:

>On 2018-04-20, John Larkin <jjlarkin@highlandtechnology.com> wrote:
>> I want a lot of these:
>>
>> https://www.dropbox.com/s/dmj4vff7mnldrcs/Impossible_Stud.JPG?raw=1
>>
>> It probably doesn't exist. Maybe a Swiss screw machine company could
>> make us a bucket full of these.
>
>how do you prevent them from pulling out when the nut is tightened?

The force is on the wider part just above the knurl.


-- 

John Larkin         Highland Technology, Inc

lunatic fringe electronics 

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#503032

On Thu, 19 Apr 2018 20:51:20 -0700, John Larkin
<jjlarkin@highlandtechnology.com> wrote:

>I want a lot of these:
>https://www.dropbox.com/s/dmj4vff7mnldrcs/Impossible_Stud.JPG?raw=1

Solderable?  In 0-80 brass might be too soft and will bend.  0-80 in
tin plated steel would probably hold together.

The 0.020" flange is rather thin and will be flimsy.  It's more like
foil and can't be cold headed.  

The OD on a 0-80 thread is 0.060".  The flange is 0.080" dia, leaving
a 0.010" wide flange.  That will not stop the part from being pushed
into the PCB hole.  Tightening the nut or whatever is used on the
threaded part will strip the 0.010" wide flange off at almost any
torque.  The 0.080" flange needs to be much wider.  Draw the part to
scale and I think you'll see the design problems.

>It probably doesn't exist. Maybe a Swiss screw machine company could
>make us a bucket full of these.

Welcome to micro-threading.  Maybe call a supplier and see what they
recommend:
<https://www.productionmachining.com/articles/making-micro-threads>

>Six of these would press into a small PCB, which could then be bolted
>onto the bottom of a bigger PCB.

Ummm... may I propose an alternative?  0-80 is too small.  Instead a
flat or pan head 2-56 or 4-40 screw goes through a hole in the PCB.  A
threaded standoff is screwed onto the 2-56 or 4-40 screw to provide a
spacer and support for the other PCB.  Washers, lock washer, and nut
to complete the sandwich.

-- 
Jeff Liebermann     jeffl@cruzio.com
150 Felker St #D    http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann     AE6KS    831-336-2558

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#503040

fredag den 20. april 2018 kl. 05.51.29 UTC+2 skrev John Larkin:
> I want a lot of these:
> 
> https://www.dropbox.com/s/dmj4vff7mnldrcs/Impossible_Stud.JPG?raw=1
> 
> It probably doesn't exist. Maybe a Swiss screw machine company could
> make us a bucket full of these.
> 
> Six of these would press into a small PCB, which could then be bolted
> onto the bottom of a bigger PCB.
> 
> 
> -- 
> 
> John Larkin         Highland Technology, Inc
> 
> lunatic fringe electronics

why male threads rather than female?

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#503043

On Thu, 19 Apr 2018 20:51:20 -0700, John Larkin
<jjlarkin@highlandtechnology.com> wrote:

>I want a lot of these:
>
>https://www.dropbox.com/s/dmj4vff7mnldrcs/Impossible_Stud.JPG?raw=1
>
>It probably doesn't exist. Maybe a Swiss screw machine company could
>make us a bucket full of these.
>
>Six of these would press into a small PCB, which could then be bolted
>onto the bottom of a bigger PCB.

Press-in from _backside_ (with a shoulder).
		
                                        ...Jim Thompson
-- 
| James E.Thompson                                 |    mens     |
| Analog Innovations                               |     et      |
| Analog/Mixed-Signal ASIC's and Discrete Systems  |    manus    |
| STV, Queen Creek, AZ 85142    Skype: skypeanalog |             |
| Voice:(480)460-2350  Fax: Available upon request |  Brass Rat  |
| E-mail Icon at http://www.analog-innovations.com |    1962     |

           To those of us in my age bracket...

           GREEN means inexperienced and/or incompetent.

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#503047

On Fri, 20 Apr 2018 15:08:31 -0700, Jim Thompson
<To-Email-Use-The-Envelope-Icon@On-My-Web-Site.com> wrote:

>On Thu, 19 Apr 2018 20:51:20 -0700, John Larkin
><jjlarkin@highlandtechnology.com> wrote:
>
>>I want a lot of these:
>>
>>https://www.dropbox.com/s/dmj4vff7mnldrcs/Impossible_Stud.JPG?raw=1
>>
>>It probably doesn't exist. Maybe a Swiss screw machine company could
>>make us a bucket full of these.
>>
>>Six of these would press into a small PCB, which could then be bolted
>>onto the bottom of a bigger PCB.
>
>Press-in from _backside_ (with a shoulder).
>		
>                                        ...Jim Thompson

I can't find a 0-80 fastener like that. There are all sorts of PEM-ish
things in larger sizes. 

There would be no pull-out stress on my knurled part. We might give up
the knurl and solder the pins onto the baby board.

I'm getting quotes from screw-machine companies, but they are
expensive. Over $2 each at first, over $1 in quantity.


-- 

John Larkin         Highland Technology, Inc
picosecond timing   precision measurement 

jlarkin att highlandtechnology dott com
http://www.highlandtechnology.com

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#503064

On Fri, 20 Apr 2018 16:48:04 -0700, John Larkin wrote:

> On Fri, 20 Apr 2018 15:08:31 -0700, Jim Thompson
> <To-Email-Use-The-Envelope-Icon@On-My-Web-Site.com> wrote:
> 
>>On Thu, 19 Apr 2018 20:51:20 -0700, John Larkin
>><jjlarkin@highlandtechnology.com> wrote:
>>
>>>I want a lot of these:
>>>
>>>https://www.dropbox.com/s/dmj4vff7mnldrcs/Impossible_Stud.JPG?raw=1
>>>
>>>It probably doesn't exist. Maybe a Swiss screw machine company could
>>>make us a bucket full of these.
>>>
>>>Six of these would press into a small PCB, which could then be bolted
>>>onto the bottom of a bigger PCB.
>>
>>Press-in from _backside_ (with a shoulder).
>>		
>>                                        ...Jim Thompson
> 
> I can't find a 0-80 fastener like that. There are all sorts of PEM-ish
> things in larger sizes. 
> 
> There would be no pull-out stress on my knurled part. We might give up
> the knurl and solder the pins onto the baby board.
> 
> I'm getting quotes from screw-machine companies, but they are
> expensive. Over $2 each at first, over $1 in quantity.

When you need the impossible screw or stud or net or bracket it's
time to step back and re-think your mechanical.  Is the baby
board size cast in stone due to some other limit?  It may be
cheaper to increase the size of that board and use more standard
screws.  As you said, this product may be a no-go and to get
a decent price you may have a bunch of inventory you will never
use.

What is the max component height on the baby board?  Keep
your screw head height at or below that.  If it's getting
that hot I suspect there is something larger than a 0402 on
there.  Put the PEM on the motherboard and find a 20 thou
or close thick washer to use as a standoff.

-- 
Chisolm
Republic of Texas

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#503053

After seeing what info you've added in replies but abstained from in the OP:

How about clamping the board between two plates, with gap pad on either 
side?  No screws needed at all.

Tim

-- 
Seven Transistor Labs, LLC
Electrical Engineering Consultation and Contract Design
Website: https://www.seventransistorlabs.com/

"John Larkin" <jjlarkin@highlandtechnology.com> wrote in message 
news:umoidd15080nk6v6c67nuff55b6523qfd4@4ax.com...
>I want a lot of these:
>
> https://www.dropbox.com/s/dmj4vff7mnldrcs/Impossible_Stud.JPG?raw=1
>
> It probably doesn't exist. Maybe a Swiss screw machine company could
> make us a bucket full of these.
>
> Six of these would press into a small PCB, which could then be bolted
> onto the bottom of a bigger PCB.
>
>
> -- 
>
> John Larkin         Highland Technology, Inc
>
> lunatic fringe electronics
> 

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#503057

On Thursday, April 19, 2018 at 11:51:29 PM UTC-4, John Larkin wrote:
> I want a lot of these:
> 
> https://www.dropbox.com/s/dmj4vff7mnldrcs/Impossible_Stud.JPG?raw=1
> 
> It probably doesn't exist. Maybe a Swiss screw machine company could
> make us a bucket full of these.
> 
> Six of these would press into a small PCB, which could then be bolted
> onto the bottom of a bigger PCB.
> 
> 
> -- 
> 
> John Larkin         Highland Technology, Inc
> 
> lunatic fringe electronics

Isn't that just an off-label use of a socket head cap screw?   Press the knurled SHCS into the PCB and secure in place with epoxy.   There are also PEM style studs, but I don't know how small they get.

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#503075

John Larkin wrote:
> I want a lot of these:
>
> https://www.dropbox.com/s/dmj4vff7mnldrcs/Impossible_Stud.JPG?raw=1
>
> It probably doesn't exist. Maybe a Swiss screw machine company could
> make us a bucket full of these.
>
> Six of these would press into a small PCB, which could then be bolted
> onto the bottom of a bigger PCB.
>
>
   How about a MillMax press-fit turret?

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#503110

fredag den 20. april 2018 kl. 05.51.29 UTC+2 skrev John Larkin:
> I want a lot of these:
> 
> https://www.dropbox.com/s/dmj4vff7mnldrcs/Impossible_Stud.JPG?raw=1
> 
> It probably doesn't exist. Maybe a Swiss screw machine company could
> make us a bucket full of these.
> 
> Six of these would press into a small PCB, which could then be bolted
> onto the bottom of a bigger PCB.
> 

why male threads, how about https://www.tindie.com/products/TEMProducts/tcap-4325-thermal-connector/

far too expensive, but I'm sure there are similar

 

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#503120

On Sat, 21 Apr 2018 13:06:51 -0700 (PDT), Lasse Langwadt Christensen
<langwadt@fonz.dk> wrote:

>fredag den 20. april 2018 kl. 05.51.29 UTC+2 skrev John Larkin:
>> I want a lot of these:
>> 
>> https://www.dropbox.com/s/dmj4vff7mnldrcs/Impossible_Stud.JPG?raw=1
>> 
>> It probably doesn't exist. Maybe a Swiss screw machine company could
>> make us a bucket full of these.
>> 
>> Six of these would press into a small PCB, which could then be bolted
>> onto the bottom of a bigger PCB.
>> 
>
>why male threads, how about https://www.tindie.com/products/TEMProducts/tcap-4325-thermal-connector/
>
>far too expensive, but I'm sure there are similar
>
> 
>
>

That is interesting, sort of a massive thermal via. But I don't see
any dimensions.


-- 

John Larkin         Highland Technology, Inc

lunatic fringe electronics 

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#503123

søndag den 22. april 2018 kl. 00.29.38 UTC+2 skrev John Larkin:
> On Sat, 21 Apr 2018 13:06:51 -0700 (PDT), Lasse Langwadt Christensen
> <langwadt@fonz.dk> wrote:
> 
> >fredag den 20. april 2018 kl. 05.51.29 UTC+2 skrev John Larkin:
> >> I want a lot of these:
> >> 
> >> https://www.dropbox.com/s/dmj4vff7mnldrcs/Impossible_Stud.JPG?raw=1
> >> 
> >> It probably doesn't exist. Maybe a Swiss screw machine company could
> >> make us a bucket full of these.
> >> 
> >> Six of these would press into a small PCB, which could then be bolted
> >> onto the bottom of a bigger PCB.
> >> 
> >
> >why male threads, how about https://www.tindie.com/products/TEMProducts/tcap-4325-thermal-connector/
> >
> >far too expensive, but I'm sure there are similar
> >
> > 
> >
> >
> 
> That is interesting, sort of a massive thermal via. But I don't see
> any dimensions.
> 

https://d3s5r33r268y59.cloudfront.net/datasheets/7790/2016-10-25-22-31-17/Design_Reference.pdf


from https://temproducts.wordpress.com/

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#503364

On Thu, 19 Apr 2018 20:51:20 -0700, John Larkin
<jjlarkin@highlandtechnology.com> wrote:

>I want a lot of these:
>
>https://www.dropbox.com/s/dmj4vff7mnldrcs/Impossible_Stud.JPG?raw=1
>
>It probably doesn't exist. Maybe a Swiss screw machine company could
>make us a bucket full of these.
>
>Six of these would press into a small PCB, which could then be bolted
>onto the bottom of a bigger PCB.

Tolerances on the part vs. staking die and forces on the part look
iffy. Normal clearance hole for 0-80 is 0.073. You definitely want the
disk deburred on the bottom or it won't sit flat, and if the top has a
similar fillet it will tend to extrude into the die. 

Might it be easier to make a plated part and solder it in? 

--sp 

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#503367

On Tue, 24 Apr 2018 09:10:45 -0400, Spehro Pefhany
<speffSNIP@interlogDOTyou.knowwhat> wrote:

>On Thu, 19 Apr 2018 20:51:20 -0700, John Larkin
><jjlarkin@highlandtechnology.com> wrote:
>
>>I want a lot of these:
>>
>>https://www.dropbox.com/s/dmj4vff7mnldrcs/Impossible_Stud.JPG?raw=1
>>
>>It probably doesn't exist. Maybe a Swiss screw machine company could
>>make us a bucket full of these.
>>
>>Six of these would press into a small PCB, which could then be bolted
>>onto the bottom of a bigger PCB.
>
>Tolerances on the part vs. staking die and forces on the part look
>iffy. Normal clearance hole for 0-80 is 0.073. You definitely want the
>disk deburred on the bottom or it won't sit flat, and if the top has a
>similar fillet it will tend to extrude into the die. 
>
>Might it be easier to make a plated part and solder it in? 
>
>--sp 

The screw machine people would prefer to make a solderable part and
not knurl something that small. That's OK with us... pressing in a
part is about as much hassle as soldering.

I'm trying to talk my manufacturing people into attaching the baby
board with six nuts; they prefer to plug pins into pin sockets. I'm
looking at 3 or 4 amps peak per pin with nanosecond rise times, which
is terrifying, to me, for small pin sockets.


-- 

John Larkin         Highland Technology, Inc

lunatic fringe electronics 

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#503377

On Tue, 24 Apr 2018 06:55:34 -0700, John Larkin wrote:

> On Tue, 24 Apr 2018 09:10:45 -0400, Spehro Pefhany
> <speffSNIP@interlogDOTyou.knowwhat> wrote:
> 
>>On Thu, 19 Apr 2018 20:51:20 -0700, John Larkin
>><jjlarkin@highlandtechnology.com> wrote:
>>
>>>I want a lot of these:
>>>
>>>https://www.dropbox.com/s/dmj4vff7mnldrcs/Impossible_Stud.JPG?raw=1
>>>
>>>It probably doesn't exist. Maybe a Swiss screw machine company could
>>>make us a bucket full of these.
>>>
>>>Six of these would press into a small PCB, which could then be bolted
>>>onto the bottom of a bigger PCB.
>>
>>Tolerances on the part vs. staking die and forces on the part look
>>iffy. Normal clearance hole for 0-80 is 0.073. You definitely want the
>>disk deburred on the bottom or it won't sit flat, and if the top has a
>>similar fillet it will tend to extrude into the die. 
>>
>>Might it be easier to make a plated part and solder it in? 
>>
>>--sp 
> 
> The screw machine people would prefer to make a solderable part and
> not knurl something that small. That's OK with us... pressing in a
> part is about as much hassle as soldering.
> 
> I'm trying to talk my manufacturing people into attaching the baby
> board with six nuts; they prefer to plug pins into pin sockets. I'm
> looking at 3 or 4 amps peak per pin with nanosecond rise times, which
> is terrifying, to me, for small pin sockets.

If you want to go pin/socket try the mill-max pin receptacle.

https://www.mill-max.com/products/rec/9184

is rated at 8 amps with a .040 to .050 pin.  I've used a bunch
of these in the past (smaller .025 pin size) and no problems.

Not sure what they will do to your rise times.  Get a few samples
and test.

-- 
Chisolm
Republic of Texas

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