Last month, I wrote about jar bumpers. While not technically “fishing” tools, they may help a driller avoid a fishing job if the tools are slightly stuck. Of course, a true fishing job involves a drill string either badly stuck, or broken off the drill cable and lost down the hole. This month I talk about true fishing jobs and the tools needed to accomplish them. I find it best to discuss these things when we don’t have tools down the hole. We can take an objective look at what we might need before we need it.
My years of experience have taught me to avoid (if possible) a botched fishing job. Botching it could result from:
- Using the wrong fishing tool
- Using the correct tool, but applying it in incorrect manner
- Just plain messing up
If the first attempt at a fishing job fails, the job becomes 20 to 50 times more complicated. I have talked to drillers who got a tool string stuck and, through a series of errors, got their fishing string stuck too. I even knew one driller — who passed away quite a few years ago — who got his second fishing string stuck. He had the original drilling string, with two fishing strings on top of that. At that point, he abandoned the hole. He later changed to rotary drilling. He had a plan to rotary down alongside the stuck tools and retrieve them from the hole, but I think he passed away before he tried.
It may sound defeatist, but if the first or second try at fishing tools fails in a shallow domestic or commercial well, the smart move may be to abandon the job and start over. Yes, you have to buy new drilling tools, but you may save hours and days of time — and a fair amount of money. I know this goes against the makeup of the typical driller, but sometimes abandonment is the smart choice.
Extensive fishing operations can make sense for deeper, larger-diameter holes, but not always. A good driller once told me of a 1,000-foot rotary hole. The driller was running a down the hole hammer when he twisted off his drill pipe. Apparently, the wall of the drill pipe had worn thin. He invested a lot of time and money to get the pipe and, especially, the hammer back out. Eventually, he called it a lost cause and abandoned the hole, but he told me he wished he would have made the decision sooner.
If the first attempt at a fishing job fails, the job becomes 20 to 50 times more complicated. I have talked to drillers who got a tool string stuck and, through a series of errors, got their fishing string stuck too.
To make a long story shorter, if you go fishing for cable tools — or any tools, for that matter — remember:
- Use the proper tool
- Use it in a proper manner
- Carefully — very carefully, in fact — think through your plans before you start
Your first consideration when you “go fishing”? A proper fishing string. A rope socket tops this string. For fishing, many veteran drillers prefer a solid socket to the swivel type used for normal drilling. With a solid socket, you fasten the fishing line directly to the socket with hot zinc (just as the drilling line fastens to the swivel of a drilling socket). Below the socket comes a drill stem. You can usually use a shorter stem than the one used in drilling operations. In my part of the country, the stem used in drilling will generally run from 12 to 18 feet in length. For fishing, I would recommend a stem 8 to 12 feet in length, although you can use a longer stem. You want a stem long enough to exert a jarring force strong enough to get the stuck tools loose, but you want to keep the combined weight of the fishing string and the drilling string within the rig’s lifting capacity.
The next part of the fishing string is very important: a set of fishing jars. Fishing jars are just like drilling jars except they have a longer stroke. Popular cable-tool rigs in my area have a short stroke of around 18 inches — the fishing stroke. On a rig like this, you would want fishing jars with a workable stroke of 24 inches at a bare minimum, and a 30-inch stroke might not be a bad idea. Even larger rigs will have a fishing stroke as short as 24 inches, so those 30-inch-stroke fishing jars will work.
Let me offer a word of caution. Faced with a fishing job, some drillers may resort to using a set of nearly worn-out drilling jars. While the length and stroke due to wear may work, resist this dangerous option. These older jars could break. A set of broken jars in any hole presents a huge problem.
The bottom tool in a fishing string attaches to the stuck string to start to pull it out. I will discuss many of these types tools in future columns.
Fishing for stuck cable tools can prove frustrating and, sometimes, very expensive. The best advice I can give? Avoid fishing at all costs. Sometimes, however, it cannot be avoided. If you, sadly, have a fishing job on your hands, think carefully about it before you send fishing tools down the hole. Next time, I will write about some of those many tools that grab the stuck string.
We have had a beautiful fall here in southern Michigan, but a lack of rain has left the ground parched. This, however, has helped the farmers harvest their soybeans and corn. Most all the leaves have fallen from the trees and a fierce wind a couple days ago blew them to wherever — sometimes into big piles. Most lawns are still green, though not growing at all. Until next time, continue to work hard, enjoy life and think carefully about any fishing job you have on a cable-tool rig.
For more John Schmitt columns, visit www.thedriller.com/schmitt.