[HBR] Coil Forms

[N2EY at aol.com]

In a message dated 9/16/06 7:40:13 AM Eastern Daylight Time, 
shoppa_hbr at trailing-edge.com writes:


> Indeed most of those old coil forms were styrene, or at least the
> melting point was nearly identical because inevitably I always
> did some slight gooeyfying in soldering on those pins :-).
> 

There's a way to avoid that problem.

First, note that some of those forms have nickel-plated pins, which are 
difficult to solder. Use a small flat file to remove the nickel plating at the tips 
of the pins so you can solder direct to the brass underneath.

Second, do not try to use some dinky little iron for this job - you need 
serious thermal capacity.

Third, get an old wafer socket for each size of form. These are the sockets 
where you can see the pin ends when the tube or coil is plugged in. The cheap 
bakelites are best because they're so thin. Plug the form into the socket and 
then solder the pins - the socket will prevent the pins from moving, and the 
contacts act as a bit of a heatsink. 

If you are making more than one or two coils, you might want to mount the 
socket upside down in an old chassis or other bracket so it holds the coil 
solidly, and you have both hands free.

73 de Jim, N2EY