back to 25ft 10ga power drops

4. if the contact won't go in all the way:


Placing large #10 into a PP45 contact really pushes the available space in the housing. Unfortunately, if the
contact is stubbornly stopping shy of locking with the spring, you can't see what the contact is hanging up on
inside the housing. Further complicating things, the inside of the housing is a surprisingly complex shape,
which just makes it that much harder to figure out why you can't shove the wire that final 2mm and are just
crushing and bending the wire at the housing while your fingers are getting sore.

First off, the "top" of the inside (top being the "tongue" side on the front) has a "shelf" where it suddenly
narrows, which is the "pivot point" the contact rocks on when being connected to anther powerpole. On SB50
contacts, there's a little matching shelf that is really easy to accidentally fill with solder OR rosin. It doesn't
seem to cause any problems with the crimp PP45 contacts though. On the non-silder PP30 and 15 contacts,
you need to make sure you don't let solder flow out the bottom of the wire cup, because solder there will hit
the shelf on the housing and prevent it from going all the way in.

On the bottom is where the spring for the contact anchors in. You can easily see the divit on the outside,
and you'll see a bump on the inside too. So the contact will need to be flattened a little bit or it will
interfere with the rocking motion when it should be moving and compressing the spring when being plugged in.
What I mean here is you can't bend the crimp wings to be round, insert the wire, and close the wings to touch.
It will be just a little too tall.

The other problem I discovered recently after getting too aggressive with my flattening to prevent the above
issue. I thought I was safe to flatten it as much as I wanted, as long as I didn't get close to the width of
the contact, but surprise, it gets NARROWER as you go in. I finally figured out I was gouging into the sides
of the inside of the housing after a close inspection. Rather than crush it further with my pliers, I used a
smooth-jaw Panavise to compress it from the sides.

This ended up giving the contact a square profile, since it had already been crushed top-to-bottom, and I was
now crushing it side-to-side. But it went in and immediately bottomed out and clicked on both contacts. This
took me well over an hour of trying different things to finally figure out, because I had no way to measure
the inside width of the contact, and had just assumed it would stay the same width inside unless there was an
obvious change like the shelf on the top or the bump for the spring on the bottom. It never occurred to me
that it might gradually get narrower toward the front. The magic width? 4.50 mm. 4.65 is TOO MUCH. It's
pretty picky. Use a caliper if you have one. (digital calipers are getting cheap, everyone should have one)



stainless steel digital caliper:

$22 on Amazon


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