Tuesday, February 26, 2013

Crimpers: the Good and the Bad

The second article I wrote for Practical Sailor was a 1-year salt environment chamber test of anti-corrosion greases and sprays, terminal blocks, wire types, and crimp connections. Over 300 crimps and 200 screw connections made for the test without a single failure or increase in resistance with time (some quick-connects failed). Credit goes to proper tools; ratchet crimpers make reliable connections time-after-time because they do not release until a preset compression is met.

Proper ratchet crimpers. Most are good, but skip Harbor Freight; I looked at theirs and the action was sloppy. Required features are adjustable tension (small wheel near hinge marked +/-) and dies that make 2 crimps. Proper strippers are important too. While it is certainly possible to use a knife, with stranded wire it is important not to nick strands.

Today I faced a home repair task; an oven with a fried selector switch. After 40 years there was also some failed wire and connectors, so a dozen crimps would be required. I keep my good crimpers on the boat, so I pulled out a pair of cheap ones I've thrown away and then recovered from the can a few times. I've been meaning to pitch them for years, but I'm cheap and good ratchet crimpers cost. And squeeze as I might, I couldn't make a crimp that wouldn't pull of the wire if given a good forceful yank by a helper. Not good enough.

Gone for good this time. Their very existence should violate the electrical code.

Home Depot and Lowes don't carry ratchet crimpers, only the pliers-type, which I dislike very much. Electrical supply houses do, but they're not open after 5 o'clock. Advance Auto Parts carries a perfectly serviceable pair for $29.00, which is quite an acceptable price when you're heading out of town and your wife would like to have her kitchen put back together. They also get thumbs-up for quality, whatever that's worth. Not quite as nice as my Ancor crimpers (for 2.6 times the price) but very, very close.

As with any crimpers, before starting a project make a test crimp with the wire and fitting brand you will use. Take the finish crimp to the bench vise, clamp it in and pull as hard as you can. The wire should not pull out without significant damage and significant effort.

1 comment:

  1. I have a crimper that I bought ages ago when working on the wiring on a submersible well pump. It looks sort of like a pair of dikes, being made of machined forgings, instead of the stamped sheet metal like the cheap ones. It works well.

    But I freely admit to crimper envy for your ratchet one.

    And yes, a one-handed wire stripper is a must too.

    s/v Eolian