It happens now and again that my steel fishtape loses its hook — either I have to cut it off, or (less frequently) it breaks off. Not only do I want the hook for convenience, but you absolutely need it. If you don’t put a bluntly curved end on it, it cannot be pushed forward. And you obviously cannot sufficiently rely on electrical tape to hold the wire you are pulling back.
So my question is: How do you guys bend a new hook? Usually I need to do this when I am in an attic or basement, so I try it with two pairs of linemens pliers. But even when I take it elsewhere to put it in a vise, it often breaks. Either way, it is almost impossible to get that nicely formed (sort of g-shaped) end on it, like the tape was bent when new. That nice shape really makes a big difference when pulling back and trying not to get accidentally stuck on something.
This spring steel is so tough that it really resists bending without breaking. Maybe everyone else knows they have to use a torch? Or maybe there’s a jig for bending the right shape? This must happen to sparkies a lot more often than to me, and (without degenerating into another discussion of steel vs SS vs braided vs nylon etc) they must have an efficient way to get a new hook on there. I know it’s sort of a silly basic question, but I wouldn’t mind a step by step description of what you pros do.
Thanks,
Rick
Replies
swap it with yer buddies new one when he is at lunch..always works.
Spheramid Enterprises Architectural Woodworks
Iffin ya cain't spell it, don't eat it
heat it..
bend it...
retemper it...
swap it for Sphere's...
I'm curious why you called it a "fishtape". I know it says that on the package, but I've never heard any electrician call it anything other than a "snake", from my grandfather to the union guys at work.
It's called that because you use it to 'go fishing' for wires you know are somewhere in that stud bay but which you can't see...like the one you shoved up from below so you can hook it from above to snake a new run through a fire-stop and a sole plate....
And sometimes it takes just as long to hook the wire you need as it does to catch a fish....
Dinosaur
A day may come when the courage of men fails,when we forsake our friends and break all bonds of fellowship...
But it is not this day.
Must be regional or something. I've been in the northeast mostly forever and that's what everyone calls it. As noted, "We'll have to fish it through the wall" is the standard jargon. Snakes are what plumbers use....
Rick
Heat it up with an oxy-acetylene torch until the metal where you want the bend is cherry red. Take the flame off the fish tape, and bend it while it's hot.
Let it air-cool. Don't quench it. It'll be less likely to break off next time.
(If you don't have a full-sized cutting/brazing set, one of those little Bernzomatic Oxy-MAPP toys'll do it okay. You should always keep one in your glove compartment fer emergencies like fixing the hinges on yer lunch bucket, LOL....)
Dinosaur
A day may come when the courage of men fails,when we forsake our friends and break all bonds of fellowship...
But it is not this day.
Yours didn't come with the nice eye end on it...(or maybe you swapped for the wrong guys LOL)?
My method, also used for making replacement coil springs for most anything, propane torck works OK for small stuff like a fishtape.
1. Heat till just a dull cherry, bend with pliers to desired loop.
2. reheat to just past the color point where a magnet will not stick to the curved part of your loop, quench in water.
3. hit the end of the loop with sandpaper till you can see shiny steel, reheat to dull blue (just past straw color), let cool in air.
For springs on equipment that get a lot of fatigue, it is best to temper in and oven or slat bath for a few hours, then shot peen, but that is not needed for the little fatigue a fish tape end gets.
Thanks for the details. It's obvious to me that I wasn't doing any of the appropriate re-heating / tempering. Now I should get a much longer-lasting hook. I really appreciate knowing that I can still just use my propane torch, as I have never gotten into the hotter setups.
Rick
My dad taught me that quenching in oil results in a temper that is more "springy" and less brittle than water quenching. That's what I've generally used for stuff like this (though never done a fish tape hook). Probably not as good as a more protracted tempering process, but it's quick, simple, and relatively foolproof.
Ah, maybe we should do a thread on tempering.
I thinkmost fishtape is either 1040 or 1050 steel, which is water hardening. Others have best properties hardend in oil. All has to do with grain formation during quenching. Some of the more exotic alloys or high strength high fatigue alloys (e.g 4340) harden in air, and to normalize (remove all temper) they need to be heated for hors per nch of thickness and cooled over many more hours - gets pretty complex for aerospace or ordnance alloys. A 1/2 thick bar of 4140 (typical gun barrel alloy) when water hardened can crack when tempered or be broken by hand as there are so many residual stresses.
EDit- very basic overview and some of the terminology and what is required can be read at http://www.anvilfire.com/21centbs/index.htm
Edited 7/6/2005 11:44 pm ET by JUNKHOUND
Rick:
Dinosaur is right on. Heating and cooling will make the tempered metal more malleable. Leave it that way. It probably won't break again.
RoRo
You want the steel soft enough not to crack given the stresses. But not so soft that it opens in a conduit. I have seen ends too soft that opened during a pull on 3/4" rigid locking itself into a joint between lengths like a toggle bolt. Royal PITA.
Better yet build your own induction furnace!!!
all you need is a coil of copper pipe , a water supply, maybe a welding generator for the power supply
Jeez, for cryin out loud, hold the fish tape in one hand, hold kleins in other hand, grab end of fishtape with pliers at right angle,
or perpendicular, make a small bend, place pliers behind this small bend, fold tape onto itself SLOWLY until first small bend touches tape. Fini
tape up this new hook, you are done
hold the fish tape in one hand, hold kleins in other hand, grab end of fishtape with pliers at right angle, make a small bend, place pliers behind this small bend, fold tape onto itself SLOWLY until first small bend touches tape. Fini
That's exactly the procedure I have been using, i.e. the one that I haven't had such great experience with. First of all, you end up with a U-shaped bend (that gets stuck in the aforementioned conduit or on any other obstacle) rather than the nice g-shaped bend (with the point of the bend centered instead of offset). Secondly, that second bend (folding onto itself) either breaks while I'm doing it, or worse, during the pull.
So I'll keep doing it with two Kleins when I am in a pinch (you must have a stronger thumb than I do if you can manage the second hold with just your other hand). But I am gonna try some of the suggested alchemy when I climb back down out of the attic to get a lasting and properly shaped hook.
HAHAHA .......alchemy huh? what happened to the factory hook?"